160727d8bSWarner Losh /*- 21c7c3c6aSMatthew Dillon * Copyright (c) 1998 Matthew Dillon, 326f9a767SRodney W. Grimes * Copyright (c) 1994 John S. Dyson 4df8bae1dSRodney W. Grimes * Copyright (c) 1990 University of Utah. 5e9c0cc15SPoul-Henning Kamp * Copyright (c) 1982, 1986, 1989, 1993 6df8bae1dSRodney W. Grimes * The Regents of the University of California. All rights reserved. 7df8bae1dSRodney W. Grimes * 8df8bae1dSRodney W. Grimes * This code is derived from software contributed to Berkeley by 9df8bae1dSRodney W. Grimes * the Systems Programming Group of the University of Utah Computer 10df8bae1dSRodney W. Grimes * Science Department. 11df8bae1dSRodney W. Grimes * 12df8bae1dSRodney W. Grimes * Redistribution and use in source and binary forms, with or without 13df8bae1dSRodney W. Grimes * modification, are permitted provided that the following conditions 14df8bae1dSRodney W. Grimes * are met: 15df8bae1dSRodney W. Grimes * 1. Redistributions of source code must retain the above copyright 16df8bae1dSRodney W. Grimes * notice, this list of conditions and the following disclaimer. 17df8bae1dSRodney W. Grimes * 2. Redistributions in binary form must reproduce the above copyright 18df8bae1dSRodney W. Grimes * notice, this list of conditions and the following disclaimer in the 19df8bae1dSRodney W. Grimes * documentation and/or other materials provided with the distribution. 20df8bae1dSRodney W. Grimes * 3. All advertising materials mentioning features or use of this software 215929bcfaSPhilippe Charnier * must display the following acknowledgement: 22df8bae1dSRodney W. Grimes * This product includes software developed by the University of 23df8bae1dSRodney W. Grimes * California, Berkeley and its contributors. 24df8bae1dSRodney W. Grimes * 4. Neither the name of the University nor the names of its contributors 25df8bae1dSRodney W. Grimes * may be used to endorse or promote products derived from this software 26df8bae1dSRodney W. Grimes * without specific prior written permission. 27df8bae1dSRodney W. Grimes * 28df8bae1dSRodney W. Grimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29df8bae1dSRodney W. Grimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30df8bae1dSRodney W. Grimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31df8bae1dSRodney W. Grimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32df8bae1dSRodney W. Grimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33df8bae1dSRodney W. Grimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34df8bae1dSRodney W. Grimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35df8bae1dSRodney W. Grimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36df8bae1dSRodney W. Grimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37df8bae1dSRodney W. Grimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38df8bae1dSRodney W. Grimes * SUCH DAMAGE. 39df8bae1dSRodney W. Grimes * 401c7c3c6aSMatthew Dillon * New Swap System 411c7c3c6aSMatthew Dillon * Matthew Dillon 421c7c3c6aSMatthew Dillon * 431c7c3c6aSMatthew Dillon * Radix Bitmap 'blists'. 441c7c3c6aSMatthew Dillon * 451c7c3c6aSMatthew Dillon * - The new swapper uses the new radix bitmap code. This should scale 461c7c3c6aSMatthew Dillon * to arbitrarily small or arbitrarily large swap spaces and an almost 471c7c3c6aSMatthew Dillon * arbitrary degree of fragmentation. 481c7c3c6aSMatthew Dillon * 491c7c3c6aSMatthew Dillon * Features: 501c7c3c6aSMatthew Dillon * 511c7c3c6aSMatthew Dillon * - on the fly reallocation of swap during putpages. The new system 521c7c3c6aSMatthew Dillon * does not try to keep previously allocated swap blocks for dirty 531c7c3c6aSMatthew Dillon * pages. 541c7c3c6aSMatthew Dillon * 551c7c3c6aSMatthew Dillon * - on the fly deallocation of swap 561c7c3c6aSMatthew Dillon * 571c7c3c6aSMatthew Dillon * - No more garbage collection required. Unnecessarily allocated swap 581c7c3c6aSMatthew Dillon * blocks only exist for dirty vm_page_t's now and these are already 591c7c3c6aSMatthew Dillon * cycled (in a high-load system) by the pager. We also do on-the-fly 601c7c3c6aSMatthew Dillon * removal of invalidated swap blocks when a page is destroyed 611c7c3c6aSMatthew Dillon * or renamed. 621c7c3c6aSMatthew Dillon * 63df8bae1dSRodney W. Grimes * from: Utah $Hdr: swap_pager.c 1.4 91/04/30$ 64df8bae1dSRodney W. Grimes * 65df8bae1dSRodney W. Grimes * @(#)swap_pager.c 8.9 (Berkeley) 3/21/94 66e9c0cc15SPoul-Henning Kamp * @(#)vm_swap.c 8.5 (Berkeley) 2/17/94 67df8bae1dSRodney W. Grimes */ 68df8bae1dSRodney W. Grimes 69874651b1SDavid E. O'Brien #include <sys/cdefs.h> 70874651b1SDavid E. O'Brien __FBSDID("$FreeBSD$"); 71874651b1SDavid E. O'Brien 72*69921123SKonstantin Belousov #include "opt_compat.h" 73e9c0cc15SPoul-Henning Kamp #include "opt_swap.h" 74e9c0cc15SPoul-Henning Kamp #include "opt_vm.h" 75e9c0cc15SPoul-Henning Kamp 76df8bae1dSRodney W. Grimes #include <sys/param.h> 77df8bae1dSRodney W. Grimes #include <sys/systm.h> 78af647ddeSBruce Evans #include <sys/conf.h> 7964abb5a5SDavid Greenman #include <sys/kernel.h> 80acd3428bSRobert Watson #include <sys/priv.h> 81df8bae1dSRodney W. Grimes #include <sys/proc.h> 829626b608SPoul-Henning Kamp #include <sys/bio.h> 83df8bae1dSRodney W. Grimes #include <sys/buf.h> 84e9c0cc15SPoul-Henning Kamp #include <sys/disk.h> 85e9c0cc15SPoul-Henning Kamp #include <sys/fcntl.h> 86e9c0cc15SPoul-Henning Kamp #include <sys/mount.h> 87e9c0cc15SPoul-Henning Kamp #include <sys/namei.h> 88df8bae1dSRodney W. Grimes #include <sys/vnode.h> 89df8bae1dSRodney W. Grimes #include <sys/malloc.h> 901ba5ad42SEdward Tomasz Napierala #include <sys/racct.h> 913364c323SKonstantin Belousov #include <sys/resource.h> 923364c323SKonstantin Belousov #include <sys/resourcevar.h> 9389f6b863SAttilio Rao #include <sys/rwlock.h> 94327f4e83SMatthew Dillon #include <sys/sysctl.h> 95e9c0cc15SPoul-Henning Kamp #include <sys/sysproto.h> 961c7c3c6aSMatthew Dillon #include <sys/blist.h> 971c7c3c6aSMatthew Dillon #include <sys/lock.h> 980cddd8f0SMatthew Dillon #include <sys/sx.h> 99936524aaSMatthew Dillon #include <sys/vmmeter.h> 100df8bae1dSRodney W. Grimes 101aed55708SRobert Watson #include <security/mac/mac_framework.h> 102aed55708SRobert Watson 103df8bae1dSRodney W. Grimes #include <vm/vm.h> 10421cd6e62SSeigo Tanimura #include <vm/pmap.h> 10521cd6e62SSeigo Tanimura #include <vm/vm_map.h> 10621cd6e62SSeigo Tanimura #include <vm/vm_kern.h> 107efeaf95aSDavid Greenman #include <vm/vm_object.h> 108df8bae1dSRodney W. Grimes #include <vm/vm_page.h> 109efeaf95aSDavid Greenman #include <vm/vm_pager.h> 110df8bae1dSRodney W. Grimes #include <vm/vm_pageout.h> 111e9c0cc15SPoul-Henning Kamp #include <vm/vm_param.h> 112df8bae1dSRodney W. Grimes #include <vm/swap_pager.h> 113efeaf95aSDavid Greenman #include <vm/vm_extern.h> 114670d17b5SJeff Roberson #include <vm/uma.h> 115df8bae1dSRodney W. Grimes 116dee34ca4SPoul-Henning Kamp #include <geom/geom.h> 117dee34ca4SPoul-Henning Kamp 118ec38b344SPoul-Henning Kamp /* 11915523cf7SKonstantin Belousov * SWB_NPAGES must be a power of 2. It may be set to 1, 2, 4, 8, 16 12015523cf7SKonstantin Belousov * or 32 pages per allocation. 12115523cf7SKonstantin Belousov * The 32-page limit is due to the radix code (kern/subr_blist.c). 122ec38b344SPoul-Henning Kamp */ 123ec38b344SPoul-Henning Kamp #ifndef MAX_PAGEOUT_CLUSTER 124ec38b344SPoul-Henning Kamp #define MAX_PAGEOUT_CLUSTER 16 125ec38b344SPoul-Henning Kamp #endif 126ec38b344SPoul-Henning Kamp 127ec38b344SPoul-Henning Kamp #if !defined(SWB_NPAGES) 128ec38b344SPoul-Henning Kamp #define SWB_NPAGES MAX_PAGEOUT_CLUSTER 129ec38b344SPoul-Henning Kamp #endif 130ec38b344SPoul-Henning Kamp 131ec38b344SPoul-Henning Kamp /* 13215523cf7SKonstantin Belousov * The swblock structure maps an object and a small, fixed-size range 13315523cf7SKonstantin Belousov * of page indices to disk addresses within a swap area. 13415523cf7SKonstantin Belousov * The collection of these mappings is implemented as a hash table. 13515523cf7SKonstantin Belousov * Unused disk addresses within a swap area are allocated and managed 13615523cf7SKonstantin Belousov * using a blist. 137ec38b344SPoul-Henning Kamp */ 138ec38b344SPoul-Henning Kamp #define SWCORRECT(n) (sizeof(void *) * (n) / sizeof(daddr_t)) 139ec38b344SPoul-Henning Kamp #define SWAP_META_PAGES (SWB_NPAGES * 2) 140ec38b344SPoul-Henning Kamp #define SWAP_META_MASK (SWAP_META_PAGES - 1) 141ec38b344SPoul-Henning Kamp 142e9c0cc15SPoul-Henning Kamp struct swblock { 143e9c0cc15SPoul-Henning Kamp struct swblock *swb_hnext; 144e9c0cc15SPoul-Henning Kamp vm_object_t swb_object; 145e9c0cc15SPoul-Henning Kamp vm_pindex_t swb_index; 146e9c0cc15SPoul-Henning Kamp int swb_count; 147e9c0cc15SPoul-Henning Kamp daddr_t swb_pages[SWAP_META_PAGES]; 148e9c0cc15SPoul-Henning Kamp }; 149e9c0cc15SPoul-Henning Kamp 1502c4992dbSAlan Cox static MALLOC_DEFINE(M_VMPGDATA, "vm_pgdata", "swap pager private data"); 15120da9c2eSPoul-Henning Kamp static struct mtx sw_dev_mtx; 1528f60c087SPoul-Henning Kamp static TAILQ_HEAD(, swdevt) swtailq = TAILQ_HEAD_INITIALIZER(swtailq); 1538f60c087SPoul-Henning Kamp static struct swdevt *swdevhd; /* Allocate from here next */ 1548f60c087SPoul-Henning Kamp static int nswapdev; /* Number of swap devices */ 1558f60c087SPoul-Henning Kamp int swap_pager_avail; 15604533e1eSKonstantin Belousov static struct sx swdev_syscall_lock; /* serialize swap(on|off) */ 157e9c0cc15SPoul-Henning Kamp 1583364c323SKonstantin Belousov static vm_ooffset_t swap_total; 1598a9c731fSIvan Voras SYSCTL_QUAD(_vm, OID_AUTO, swap_total, CTLFLAG_RD, &swap_total, 0, 1608a9c731fSIvan Voras "Total amount of available swap storage."); 1613364c323SKonstantin Belousov static vm_ooffset_t swap_reserved; 1628a9c731fSIvan Voras SYSCTL_QUAD(_vm, OID_AUTO, swap_reserved, CTLFLAG_RD, &swap_reserved, 0, 1638a9c731fSIvan Voras "Amount of swap storage needed to back all allocated anonymous memory."); 1643364c323SKonstantin Belousov static int overcommit = 0; 1658a9c731fSIvan Voras SYSCTL_INT(_vm, OID_AUTO, overcommit, CTLFLAG_RW, &overcommit, 0, 1668a9c731fSIvan Voras "Configure virtual memory overcommit behavior. See tuning(7) " 1678a9c731fSIvan Voras "for details."); 16861203277SDag-Erling Smørgrav static unsigned long swzone; 16961203277SDag-Erling Smørgrav SYSCTL_ULONG(_vm, OID_AUTO, swzone, CTLFLAG_RD, &swzone, 0, 17061203277SDag-Erling Smørgrav "Actual size of swap metadata zone"); 17161203277SDag-Erling Smørgrav static unsigned long swap_maxpages; 17261203277SDag-Erling Smørgrav SYSCTL_ULONG(_vm, OID_AUTO, swap_maxpages, CTLFLAG_RD, &swap_maxpages, 0, 17361203277SDag-Erling Smørgrav "Maximum amount of swap supported"); 1743364c323SKonstantin Belousov 1753364c323SKonstantin Belousov /* bits from overcommit */ 1763364c323SKonstantin Belousov #define SWAP_RESERVE_FORCE_ON (1 << 0) 1773364c323SKonstantin Belousov #define SWAP_RESERVE_RLIMIT_ON (1 << 1) 1783364c323SKonstantin Belousov #define SWAP_RESERVE_ALLOW_NONWIRED (1 << 2) 1793364c323SKonstantin Belousov 1803364c323SKonstantin Belousov int 1813364c323SKonstantin Belousov swap_reserve(vm_ooffset_t incr) 1823364c323SKonstantin Belousov { 1833364c323SKonstantin Belousov 184ef694c1aSEdward Tomasz Napierala return (swap_reserve_by_cred(incr, curthread->td_ucred)); 1853364c323SKonstantin Belousov } 1863364c323SKonstantin Belousov 1873364c323SKonstantin Belousov int 188ef694c1aSEdward Tomasz Napierala swap_reserve_by_cred(vm_ooffset_t incr, struct ucred *cred) 1893364c323SKonstantin Belousov { 1905c0e1c11SKonstantin Belousov vm_ooffset_t r, s; 1913364c323SKonstantin Belousov int res, error; 1923364c323SKonstantin Belousov static int curfail; 1933364c323SKonstantin Belousov static struct timeval lastfail; 194ef694c1aSEdward Tomasz Napierala struct uidinfo *uip; 195ef694c1aSEdward Tomasz Napierala 196ef694c1aSEdward Tomasz Napierala uip = cred->cr_ruidinfo; 1973364c323SKonstantin Belousov 1983364c323SKonstantin Belousov if (incr & PAGE_MASK) 1993364c323SKonstantin Belousov panic("swap_reserve: & PAGE_MASK"); 2003364c323SKonstantin Belousov 201afcc55f3SEdward Tomasz Napierala #ifdef RACCT 2024b5c9cf6SEdward Tomasz Napierala if (racct_enable) { 2031ba5ad42SEdward Tomasz Napierala PROC_LOCK(curproc); 2041ba5ad42SEdward Tomasz Napierala error = racct_add(curproc, RACCT_SWAP, incr); 2051ba5ad42SEdward Tomasz Napierala PROC_UNLOCK(curproc); 2061ba5ad42SEdward Tomasz Napierala if (error != 0) 2071ba5ad42SEdward Tomasz Napierala return (0); 2084b5c9cf6SEdward Tomasz Napierala } 209afcc55f3SEdward Tomasz Napierala #endif 2101ba5ad42SEdward Tomasz Napierala 2113364c323SKonstantin Belousov res = 0; 2123364c323SKonstantin Belousov mtx_lock(&sw_dev_mtx); 2133364c323SKonstantin Belousov r = swap_reserved + incr; 2143364c323SKonstantin Belousov if (overcommit & SWAP_RESERVE_ALLOW_NONWIRED) { 21544f1c916SBryan Drewery s = vm_cnt.v_page_count - vm_cnt.v_free_reserved - vm_cnt.v_wire_count; 2163364c323SKonstantin Belousov s *= PAGE_SIZE; 2173364c323SKonstantin Belousov } else 2183364c323SKonstantin Belousov s = 0; 2193364c323SKonstantin Belousov s += swap_total; 2203364c323SKonstantin Belousov if ((overcommit & SWAP_RESERVE_FORCE_ON) == 0 || r <= s || 2213364c323SKonstantin Belousov (error = priv_check(curthread, PRIV_VM_SWAP_NOQUOTA)) == 0) { 2223364c323SKonstantin Belousov res = 1; 2233364c323SKonstantin Belousov swap_reserved = r; 2243364c323SKonstantin Belousov } 2253364c323SKonstantin Belousov mtx_unlock(&sw_dev_mtx); 2263364c323SKonstantin Belousov 2273364c323SKonstantin Belousov if (res) { 2283364c323SKonstantin Belousov UIDINFO_VMSIZE_LOCK(uip); 2295c0e1c11SKonstantin Belousov if ((overcommit & SWAP_RESERVE_RLIMIT_ON) != 0 && 230f6f6d240SMateusz Guzik uip->ui_vmsize + incr > lim_cur(curthread, RLIMIT_SWAP) && 2315c0e1c11SKonstantin Belousov priv_check(curthread, PRIV_VM_SWAP_NORLIMIT)) 2323364c323SKonstantin Belousov res = 0; 2333364c323SKonstantin Belousov else 2343364c323SKonstantin Belousov uip->ui_vmsize += incr; 2353364c323SKonstantin Belousov UIDINFO_VMSIZE_UNLOCK(uip); 2363364c323SKonstantin Belousov if (!res) { 2373364c323SKonstantin Belousov mtx_lock(&sw_dev_mtx); 2383364c323SKonstantin Belousov swap_reserved -= incr; 2393364c323SKonstantin Belousov mtx_unlock(&sw_dev_mtx); 2403364c323SKonstantin Belousov } 2413364c323SKonstantin Belousov } 2423364c323SKonstantin Belousov if (!res && ppsratecheck(&lastfail, &curfail, 1)) { 2433364c323SKonstantin Belousov printf("uid %d, pid %d: swap reservation for %jd bytes failed\n", 244134465d7SKonstantin Belousov uip->ui_uid, curproc->p_pid, incr); 2453364c323SKonstantin Belousov } 2463364c323SKonstantin Belousov 247afcc55f3SEdward Tomasz Napierala #ifdef RACCT 2481ba5ad42SEdward Tomasz Napierala if (!res) { 2491ba5ad42SEdward Tomasz Napierala PROC_LOCK(curproc); 2501ba5ad42SEdward Tomasz Napierala racct_sub(curproc, RACCT_SWAP, incr); 2511ba5ad42SEdward Tomasz Napierala PROC_UNLOCK(curproc); 2521ba5ad42SEdward Tomasz Napierala } 253afcc55f3SEdward Tomasz Napierala #endif 2541ba5ad42SEdward Tomasz Napierala 2553364c323SKonstantin Belousov return (res); 2563364c323SKonstantin Belousov } 2573364c323SKonstantin Belousov 2583364c323SKonstantin Belousov void 2593364c323SKonstantin Belousov swap_reserve_force(vm_ooffset_t incr) 2603364c323SKonstantin Belousov { 2613364c323SKonstantin Belousov struct uidinfo *uip; 2623364c323SKonstantin Belousov 2633364c323SKonstantin Belousov mtx_lock(&sw_dev_mtx); 2643364c323SKonstantin Belousov swap_reserved += incr; 2653364c323SKonstantin Belousov mtx_unlock(&sw_dev_mtx); 2663364c323SKonstantin Belousov 267afcc55f3SEdward Tomasz Napierala #ifdef RACCT 2681ba5ad42SEdward Tomasz Napierala PROC_LOCK(curproc); 2691ba5ad42SEdward Tomasz Napierala racct_add_force(curproc, RACCT_SWAP, incr); 2701ba5ad42SEdward Tomasz Napierala PROC_UNLOCK(curproc); 271afcc55f3SEdward Tomasz Napierala #endif 2721ba5ad42SEdward Tomasz Napierala 2733364c323SKonstantin Belousov uip = curthread->td_ucred->cr_ruidinfo; 2743364c323SKonstantin Belousov PROC_LOCK(curproc); 2753364c323SKonstantin Belousov UIDINFO_VMSIZE_LOCK(uip); 2763364c323SKonstantin Belousov uip->ui_vmsize += incr; 2773364c323SKonstantin Belousov UIDINFO_VMSIZE_UNLOCK(uip); 2783364c323SKonstantin Belousov PROC_UNLOCK(curproc); 2793364c323SKonstantin Belousov } 2803364c323SKonstantin Belousov 2813364c323SKonstantin Belousov void 2823364c323SKonstantin Belousov swap_release(vm_ooffset_t decr) 2833364c323SKonstantin Belousov { 284ef694c1aSEdward Tomasz Napierala struct ucred *cred; 2853364c323SKonstantin Belousov 2863364c323SKonstantin Belousov PROC_LOCK(curproc); 287ef694c1aSEdward Tomasz Napierala cred = curthread->td_ucred; 288ef694c1aSEdward Tomasz Napierala swap_release_by_cred(decr, cred); 2893364c323SKonstantin Belousov PROC_UNLOCK(curproc); 2903364c323SKonstantin Belousov } 2913364c323SKonstantin Belousov 2923364c323SKonstantin Belousov void 293ef694c1aSEdward Tomasz Napierala swap_release_by_cred(vm_ooffset_t decr, struct ucred *cred) 2943364c323SKonstantin Belousov { 295ef694c1aSEdward Tomasz Napierala struct uidinfo *uip; 296ef694c1aSEdward Tomasz Napierala 297ef694c1aSEdward Tomasz Napierala uip = cred->cr_ruidinfo; 2983364c323SKonstantin Belousov 2993364c323SKonstantin Belousov if (decr & PAGE_MASK) 3003364c323SKonstantin Belousov panic("swap_release: & PAGE_MASK"); 3013364c323SKonstantin Belousov 3023364c323SKonstantin Belousov mtx_lock(&sw_dev_mtx); 3033364c323SKonstantin Belousov if (swap_reserved < decr) 3043364c323SKonstantin Belousov panic("swap_reserved < decr"); 3053364c323SKonstantin Belousov swap_reserved -= decr; 3063364c323SKonstantin Belousov mtx_unlock(&sw_dev_mtx); 3073364c323SKonstantin Belousov 3083364c323SKonstantin Belousov UIDINFO_VMSIZE_LOCK(uip); 3093364c323SKonstantin Belousov if (uip->ui_vmsize < decr) 3103364c323SKonstantin Belousov printf("negative vmsize for uid = %d\n", uip->ui_uid); 3113364c323SKonstantin Belousov uip->ui_vmsize -= decr; 3123364c323SKonstantin Belousov UIDINFO_VMSIZE_UNLOCK(uip); 3131ba5ad42SEdward Tomasz Napierala 3141ba5ad42SEdward Tomasz Napierala racct_sub_cred(cred, RACCT_SWAP, decr); 3153364c323SKonstantin Belousov } 3163364c323SKonstantin Belousov 3171c7c3c6aSMatthew Dillon #define SWM_FREE 0x02 /* free, period */ 3181c7c3c6aSMatthew Dillon #define SWM_POP 0x04 /* pop out */ 31926f9a767SRodney W. Grimes 3207dea2c2eSAlan Cox int swap_pager_full = 2; /* swap space exhaustion (task killing) */ 3217dea2c2eSAlan Cox static int swap_pager_almost_full = 1; /* swap space exhaustion (w/hysteresis)*/ 3221c7c3c6aSMatthew Dillon static int nsw_rcount; /* free read buffers */ 323327f4e83SMatthew Dillon static int nsw_wcount_sync; /* limit write buffers / synchronous */ 324327f4e83SMatthew Dillon static int nsw_wcount_async; /* limit write buffers / asynchronous */ 325327f4e83SMatthew Dillon static int nsw_wcount_async_max;/* assigned maximum */ 326327f4e83SMatthew Dillon static int nsw_cluster_max; /* maximum VOP I/O allowed */ 3271c7c3c6aSMatthew Dillon 32889c241d1SGleb Smirnoff static int sysctl_swap_async_max(SYSCTL_HANDLER_ARGS); 3294c36e917SKonstantin Belousov SYSCTL_PROC(_vm, OID_AUTO, swap_async_max, CTLTYPE_INT | CTLFLAG_RW | 3304c36e917SKonstantin Belousov CTLFLAG_MPSAFE, NULL, 0, sysctl_swap_async_max, "I", 3314c36e917SKonstantin Belousov "Maximum running async swap ops"); 33289c241d1SGleb Smirnoff 3331c7c3c6aSMatthew Dillon static struct swblock **swhash; 3341c7c3c6aSMatthew Dillon static int swhash_mask; 3357827d9b0SAlan Cox static struct mtx swhash_mtx; 3367827d9b0SAlan Cox 3370cddd8f0SMatthew Dillon static struct sx sw_alloc_sx; 338327f4e83SMatthew Dillon 3391c7c3c6aSMatthew Dillon /* 3401c7c3c6aSMatthew Dillon * "named" and "unnamed" anon region objects. Try to reduce the overhead 3411c7c3c6aSMatthew Dillon * of searching a named list by hashing it just a little. 3421c7c3c6aSMatthew Dillon */ 3431c7c3c6aSMatthew Dillon 3441c7c3c6aSMatthew Dillon #define NOBJLISTS 8 3451c7c3c6aSMatthew Dillon 3461c7c3c6aSMatthew Dillon #define NOBJLIST(handle) \ 347af647ddeSBruce Evans (&swap_pager_object_list[((int)(intptr_t)handle >> 4) & (NOBJLISTS-1)]) 3481c7c3c6aSMatthew Dillon 3491c7c3c6aSMatthew Dillon static struct pagerlst swap_pager_object_list[NOBJLISTS]; 350e9c0cc15SPoul-Henning Kamp static uma_zone_t swap_zone; 3511c7c3c6aSMatthew Dillon 3521c7c3c6aSMatthew Dillon /* 3531c7c3c6aSMatthew Dillon * pagerops for OBJT_SWAP - "swap pager". Some ops are also global procedure 3541c7c3c6aSMatthew Dillon * calls hooked from other parts of the VM system and do not appear here. 3551c7c3c6aSMatthew Dillon * (see vm/swap_pager.h). 3561c7c3c6aSMatthew Dillon */ 357ff98689dSBruce Evans static vm_object_t 35811caded3SAlfred Perlstein swap_pager_alloc(void *handle, vm_ooffset_t size, 3593364c323SKonstantin Belousov vm_prot_t prot, vm_ooffset_t offset, struct ucred *); 36011caded3SAlfred Perlstein static void swap_pager_dealloc(vm_object_t object); 361b0cd2017SGleb Smirnoff static int swap_pager_getpages(vm_object_t, vm_page_t *, int, int *, 362b0cd2017SGleb Smirnoff int *); 363b0cd2017SGleb Smirnoff static int swap_pager_getpages_async(vm_object_t, vm_page_t *, int, int *, 364b0cd2017SGleb Smirnoff int *, pgo_getpages_iodone_t, void *); 365751221fdSPoul-Henning Kamp static void swap_pager_putpages(vm_object_t, vm_page_t *, int, boolean_t, int *); 3665ea4972cSAlan Cox static boolean_t 3675ea4972cSAlan Cox swap_pager_haspage(vm_object_t object, vm_pindex_t pindex, int *before, int *after); 36811caded3SAlfred Perlstein static void swap_pager_init(void); 36911caded3SAlfred Perlstein static void swap_pager_unswapped(vm_page_t); 370b3fed13eSDavid Schultz static void swap_pager_swapoff(struct swdevt *sp); 371f708ef1bSPoul-Henning Kamp 372df8bae1dSRodney W. Grimes struct pagerops swappagerops = { 373e04e4bacSPoul-Henning Kamp .pgo_init = swap_pager_init, /* early system initialization of pager */ 374e04e4bacSPoul-Henning Kamp .pgo_alloc = swap_pager_alloc, /* allocate an OBJT_SWAP object */ 375e04e4bacSPoul-Henning Kamp .pgo_dealloc = swap_pager_dealloc, /* deallocate an OBJT_SWAP object */ 376e04e4bacSPoul-Henning Kamp .pgo_getpages = swap_pager_getpages, /* pagein */ 37790effb23SGleb Smirnoff .pgo_getpages_async = swap_pager_getpages_async, /* pagein (async) */ 378e04e4bacSPoul-Henning Kamp .pgo_putpages = swap_pager_putpages, /* pageout */ 379e04e4bacSPoul-Henning Kamp .pgo_haspage = swap_pager_haspage, /* get backing store status for page */ 380e04e4bacSPoul-Henning Kamp .pgo_pageunswapped = swap_pager_unswapped, /* remove swap related to page */ 381df8bae1dSRodney W. Grimes }; 382df8bae1dSRodney W. Grimes 3831c7c3c6aSMatthew Dillon /* 3841c7c3c6aSMatthew Dillon * dmmax is in page-sized chunks with the new swap system. It was 38564bcb9c8SMatthew Dillon * dev-bsized chunks in the old. dmmax is always a power of 2. 3861c7c3c6aSMatthew Dillon * 3871c7c3c6aSMatthew Dillon * swap_*() routines are externally accessible. swp_*() routines are 3881c7c3c6aSMatthew Dillon * internal. 3891c7c3c6aSMatthew Dillon */ 390751221fdSPoul-Henning Kamp static int dmmax; 391e9c0cc15SPoul-Henning Kamp static int nswap_lowat = 128; /* in pages, swap_pager_almost_full warn */ 392e9c0cc15SPoul-Henning Kamp static int nswap_hiwat = 512; /* in pages, swap_pager_almost_full warn */ 39326f9a767SRodney W. Grimes 3942174a0c6SKonstantin Belousov SYSCTL_INT(_vm, OID_AUTO, dmmax, CTLFLAG_RD, &dmmax, 0, 3952174a0c6SKonstantin Belousov "Maximum size of a swap block"); 396cee313c4SRobert Watson 397a5edd34aSPoul-Henning Kamp static void swp_sizecheck(void); 39811caded3SAlfred Perlstein static void swp_pager_async_iodone(struct buf *bp); 39988ad2d7bSKonstantin Belousov static int swapongeom(struct vnode *); 40059efee01SPoul-Henning Kamp static int swaponvp(struct thread *, struct vnode *, u_long); 40135918c55SChristian S.J. Peron static int swapoff_one(struct swdevt *sp, struct ucred *cred); 40224a1cce3SDavid Greenman 4031c7c3c6aSMatthew Dillon /* 4041c7c3c6aSMatthew Dillon * Swap bitmap functions 4051c7c3c6aSMatthew Dillon */ 406a5edd34aSPoul-Henning Kamp static void swp_pager_freeswapspace(daddr_t blk, int npages); 407a5edd34aSPoul-Henning Kamp static daddr_t swp_pager_getswapspace(int npages); 4081c7c3c6aSMatthew Dillon 4091c7c3c6aSMatthew Dillon /* 4101c7c3c6aSMatthew Dillon * Metadata functions 4111c7c3c6aSMatthew Dillon */ 412a5edd34aSPoul-Henning Kamp static struct swblock **swp_pager_hash(vm_object_t object, vm_pindex_t index); 41311caded3SAlfred Perlstein static void swp_pager_meta_build(vm_object_t, vm_pindex_t, daddr_t); 4142e56b64fSKonstantin Belousov static void swp_pager_meta_free(vm_object_t, vm_pindex_t, vm_pindex_t); 41511caded3SAlfred Perlstein static void swp_pager_meta_free_all(vm_object_t); 41611caded3SAlfred Perlstein static daddr_t swp_pager_meta_ctl(vm_object_t, vm_pindex_t, int); 4171c7c3c6aSMatthew Dillon 4181c7c3c6aSMatthew Dillon /* 4191c7c3c6aSMatthew Dillon * SWP_SIZECHECK() - update swap_pager_full indication 4201c7c3c6aSMatthew Dillon * 42120d3034fSMatthew Dillon * update the swap_pager_almost_full indication and warn when we are 42220d3034fSMatthew Dillon * about to run out of swap space, using lowat/hiwat hysteresis. 42320d3034fSMatthew Dillon * 42420d3034fSMatthew Dillon * Clear swap_pager_full ( task killing ) indication when lowat is met. 4251c7c3c6aSMatthew Dillon * 4261c7c3c6aSMatthew Dillon * No restrictions on call 4271c7c3c6aSMatthew Dillon * This routine may not block. 4281c7c3c6aSMatthew Dillon */ 429a5edd34aSPoul-Henning Kamp static void 4302f249180SPoul-Henning Kamp swp_sizecheck(void) 4310d94caffSDavid Greenman { 43223955314SAlfred Perlstein 4338f60c087SPoul-Henning Kamp if (swap_pager_avail < nswap_lowat) { 43420d3034fSMatthew Dillon if (swap_pager_almost_full == 0) { 4351af87c92SDavid Greenman printf("swap_pager: out of swap space\n"); 43620d3034fSMatthew Dillon swap_pager_almost_full = 1; 4372b0d37a4SMatthew Dillon } 43820d3034fSMatthew Dillon } else { 43926f9a767SRodney W. Grimes swap_pager_full = 0; 4408f60c087SPoul-Henning Kamp if (swap_pager_avail > nswap_hiwat) 44120d3034fSMatthew Dillon swap_pager_almost_full = 0; 44226f9a767SRodney W. Grimes } 4431c7c3c6aSMatthew Dillon } 4441c7c3c6aSMatthew Dillon 4451c7c3c6aSMatthew Dillon /* 446da5fd145SPeter Wemm * SWP_PAGER_HASH() - hash swap meta data 447da5fd145SPeter Wemm * 448a5edd34aSPoul-Henning Kamp * This is an helper function which hashes the swapblk given 449da5fd145SPeter Wemm * the object and page index. It returns a pointer to a pointer 450da5fd145SPeter Wemm * to the object, or a pointer to a NULL pointer if it could not 451da5fd145SPeter Wemm * find a swapblk. 452da5fd145SPeter Wemm */ 453a5edd34aSPoul-Henning Kamp static struct swblock ** 454da5fd145SPeter Wemm swp_pager_hash(vm_object_t object, vm_pindex_t index) 455da5fd145SPeter Wemm { 456da5fd145SPeter Wemm struct swblock **pswap; 457da5fd145SPeter Wemm struct swblock *swap; 458da5fd145SPeter Wemm 459da5fd145SPeter Wemm index &= ~(vm_pindex_t)SWAP_META_MASK; 460da5fd145SPeter Wemm pswap = &swhash[(index ^ (int)(intptr_t)object) & swhash_mask]; 461da5fd145SPeter Wemm while ((swap = *pswap) != NULL) { 462da5fd145SPeter Wemm if (swap->swb_object == object && 463da5fd145SPeter Wemm swap->swb_index == index 464da5fd145SPeter Wemm ) { 465da5fd145SPeter Wemm break; 466da5fd145SPeter Wemm } 467da5fd145SPeter Wemm pswap = &swap->swb_hnext; 468da5fd145SPeter Wemm } 469da5fd145SPeter Wemm return (pswap); 470da5fd145SPeter Wemm } 471da5fd145SPeter Wemm 472da5fd145SPeter Wemm /* 4731c7c3c6aSMatthew Dillon * SWAP_PAGER_INIT() - initialize the swap pager! 4741c7c3c6aSMatthew Dillon * 4751c7c3c6aSMatthew Dillon * Expected to be started from system init. NOTE: This code is run 4761c7c3c6aSMatthew Dillon * before much else so be careful what you depend on. Most of the VM 4771c7c3c6aSMatthew Dillon * system has yet to be initialized at this point. 4781c7c3c6aSMatthew Dillon */ 479f5a12711SPoul-Henning Kamp static void 4802f249180SPoul-Henning Kamp swap_pager_init(void) 481df8bae1dSRodney W. Grimes { 4821c7c3c6aSMatthew Dillon /* 4831c7c3c6aSMatthew Dillon * Initialize object lists 4841c7c3c6aSMatthew Dillon */ 4851c7c3c6aSMatthew Dillon int i; 4861c7c3c6aSMatthew Dillon 4871c7c3c6aSMatthew Dillon for (i = 0; i < NOBJLISTS; ++i) 4881c7c3c6aSMatthew Dillon TAILQ_INIT(&swap_pager_object_list[i]); 48920da9c2eSPoul-Henning Kamp mtx_init(&sw_dev_mtx, "swapdev", NULL, MTX_DEF); 49015719273SKonstantin Belousov sx_init(&sw_alloc_sx, "swspsx"); 49104533e1eSKonstantin Belousov sx_init(&swdev_syscall_lock, "swsysc"); 492df8bae1dSRodney W. Grimes 493df8bae1dSRodney W. Grimes /* 4941c7c3c6aSMatthew Dillon * Device Stripe, in PAGE_SIZE'd blocks 495df8bae1dSRodney W. Grimes */ 4961c7c3c6aSMatthew Dillon dmmax = SWB_NPAGES * 2; 4971c7c3c6aSMatthew Dillon } 49826f9a767SRodney W. Grimes 499df8bae1dSRodney W. Grimes /* 5001c7c3c6aSMatthew Dillon * SWAP_PAGER_SWAP_INIT() - swap pager initialization from pageout process 5011c7c3c6aSMatthew Dillon * 5021c7c3c6aSMatthew Dillon * Expected to be started from pageout process once, prior to entering 5031c7c3c6aSMatthew Dillon * its main loop. 504df8bae1dSRodney W. Grimes */ 50524a1cce3SDavid Greenman void 5062f249180SPoul-Henning Kamp swap_pager_swap_init(void) 507df8bae1dSRodney W. Grimes { 50861203277SDag-Erling Smørgrav unsigned long n, n2; 5090d94caffSDavid Greenman 51026f9a767SRodney W. Grimes /* 5111c7c3c6aSMatthew Dillon * Number of in-transit swap bp operations. Don't 5121c7c3c6aSMatthew Dillon * exhaust the pbufs completely. Make sure we 5131c7c3c6aSMatthew Dillon * initialize workable values (0 will work for hysteresis 5141c7c3c6aSMatthew Dillon * but it isn't very efficient). 5151c7c3c6aSMatthew Dillon * 516327f4e83SMatthew Dillon * The nsw_cluster_max is constrained by the bp->b_pages[] 5171c7c3c6aSMatthew Dillon * array (MAXPHYS/PAGE_SIZE) and our locally defined 5181c7c3c6aSMatthew Dillon * MAX_PAGEOUT_CLUSTER. Also be aware that swap ops are 5191c7c3c6aSMatthew Dillon * constrained by the swap device interleave stripe size. 520327f4e83SMatthew Dillon * 521327f4e83SMatthew Dillon * Currently we hardwire nsw_wcount_async to 4. This limit is 522327f4e83SMatthew Dillon * designed to prevent other I/O from having high latencies due to 523327f4e83SMatthew Dillon * our pageout I/O. The value 4 works well for one or two active swap 524327f4e83SMatthew Dillon * devices but is probably a little low if you have more. Even so, 525327f4e83SMatthew Dillon * a higher value would probably generate only a limited improvement 526327f4e83SMatthew Dillon * with three or four active swap devices since the system does not 527327f4e83SMatthew Dillon * typically have to pageout at extreme bandwidths. We will want 528327f4e83SMatthew Dillon * at least 2 per swap devices, and 4 is a pretty good value if you 529327f4e83SMatthew Dillon * have one NFS swap device due to the command/ack latency over NFS. 530327f4e83SMatthew Dillon * So it all works out pretty well. 53126f9a767SRodney W. Grimes */ 532ad3cce20SMatthew Dillon nsw_cluster_max = min((MAXPHYS/PAGE_SIZE), MAX_PAGEOUT_CLUSTER); 533327f4e83SMatthew Dillon 5346d541bf1SJohn Baldwin mtx_lock(&pbuf_mtx); 5351c7c3c6aSMatthew Dillon nsw_rcount = (nswbuf + 1) / 2; 536327f4e83SMatthew Dillon nsw_wcount_sync = (nswbuf + 3) / 4; 537327f4e83SMatthew Dillon nsw_wcount_async = 4; 538327f4e83SMatthew Dillon nsw_wcount_async_max = nsw_wcount_async; 5396d541bf1SJohn Baldwin mtx_unlock(&pbuf_mtx); 54024a1cce3SDavid Greenman 5411c7c3c6aSMatthew Dillon /* 5421c7c3c6aSMatthew Dillon * Initialize our zone. Right now I'm just guessing on the number 5431c7c3c6aSMatthew Dillon * we need based on the number of pages in the system. Each swblock 54461203277SDag-Erling Smørgrav * can hold 32 pages, so this is probably overkill. This reservation 545ec61f55dSMatthew Dillon * is typically limited to around 32MB by default. 5461c7c3c6aSMatthew Dillon */ 54744f1c916SBryan Drewery n = vm_cnt.v_page_count / 2; 5482f9e4e80SMatthew Dillon if (maxswzone && n > maxswzone / sizeof(struct swblock)) 5492f9e4e80SMatthew Dillon n = maxswzone / sizeof(struct swblock); 55022a5e6b9SDag-Erling Smørgrav n2 = n; 551670d17b5SJeff Roberson swap_zone = uma_zcreate("SWAPMETA", sizeof(struct swblock), NULL, NULL, 5527827d9b0SAlan Cox NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM); 553010b1ca1SDavid Schultz if (swap_zone == NULL) 554010b1ca1SDavid Schultz panic("failed to create swap_zone."); 5558355f576SJeff Roberson do { 556a4915c21SAttilio Rao if (uma_zone_reserve_kva(swap_zone, n)) 55761ce6eeeSAlfred Perlstein break; 55861ce6eeeSAlfred Perlstein /* 55961ce6eeeSAlfred Perlstein * if the allocation failed, try a zone two thirds the 56061ce6eeeSAlfred Perlstein * size of the previous attempt. 56161ce6eeeSAlfred Perlstein */ 56261ce6eeeSAlfred Perlstein n -= ((n + 2) / 3); 56361ce6eeeSAlfred Perlstein } while (n > 0); 56421cd6e62SSeigo Tanimura if (n2 != n) 56561203277SDag-Erling Smørgrav printf("Swap zone entries reduced from %lu to %lu.\n", n2, n); 56661203277SDag-Erling Smørgrav swap_maxpages = n * SWAP_META_PAGES; 56761203277SDag-Erling Smørgrav swzone = n * sizeof(struct swblock); 56822a5e6b9SDag-Erling Smørgrav n2 = n; 56924a1cce3SDavid Greenman 5701c7c3c6aSMatthew Dillon /* 5711c7c3c6aSMatthew Dillon * Initialize our meta-data hash table. The swapper does not need to 5721c7c3c6aSMatthew Dillon * be quite as efficient as the VM system, so we do not use an 5731c7c3c6aSMatthew Dillon * oversized hash table. 5741c7c3c6aSMatthew Dillon * 5751c7c3c6aSMatthew Dillon * n: size of hash table, must be power of 2 5761c7c3c6aSMatthew Dillon * swhash_mask: hash table index mask 5771c7c3c6aSMatthew Dillon */ 57861ce6eeeSAlfred Perlstein for (n = 1; n < n2 / 8; n *= 2) 5791c7c3c6aSMatthew Dillon ; 580a163d034SWarner Losh swhash = malloc(sizeof(struct swblock *) * n, M_VMPGDATA, M_WAITOK | M_ZERO); 5811c7c3c6aSMatthew Dillon swhash_mask = n - 1; 5827827d9b0SAlan Cox mtx_init(&swhash_mtx, "swap_pager swhash", NULL, MTX_DEF); 58324a1cce3SDavid Greenman } 58424a1cce3SDavid Greenman 585eb4d6a1bSKonstantin Belousov static vm_object_t 586eb4d6a1bSKonstantin Belousov swap_pager_alloc_init(void *handle, struct ucred *cred, vm_ooffset_t size, 587eb4d6a1bSKonstantin Belousov vm_ooffset_t offset) 588eb4d6a1bSKonstantin Belousov { 589eb4d6a1bSKonstantin Belousov vm_object_t object; 590eb4d6a1bSKonstantin Belousov 591eb4d6a1bSKonstantin Belousov if (cred != NULL) { 592eb4d6a1bSKonstantin Belousov if (!swap_reserve_by_cred(size, cred)) 593eb4d6a1bSKonstantin Belousov return (NULL); 594eb4d6a1bSKonstantin Belousov crhold(cred); 595eb4d6a1bSKonstantin Belousov } 596eb4d6a1bSKonstantin Belousov object = vm_object_allocate(OBJT_SWAP, OFF_TO_IDX(offset + 597eb4d6a1bSKonstantin Belousov PAGE_MASK + size)); 598eb4d6a1bSKonstantin Belousov object->handle = handle; 599eb4d6a1bSKonstantin Belousov if (cred != NULL) { 600eb4d6a1bSKonstantin Belousov object->cred = cred; 601eb4d6a1bSKonstantin Belousov object->charge = size; 602eb4d6a1bSKonstantin Belousov } 603eb4d6a1bSKonstantin Belousov object->un_pager.swp.swp_bcount = 0; 604eb4d6a1bSKonstantin Belousov return (object); 605eb4d6a1bSKonstantin Belousov } 606eb4d6a1bSKonstantin Belousov 60724a1cce3SDavid Greenman /* 6081c7c3c6aSMatthew Dillon * SWAP_PAGER_ALLOC() - allocate a new OBJT_SWAP VM object and instantiate 6091c7c3c6aSMatthew Dillon * its metadata structures. 6101c7c3c6aSMatthew Dillon * 6111c7c3c6aSMatthew Dillon * This routine is called from the mmap and fork code to create a new 612eb4d6a1bSKonstantin Belousov * OBJT_SWAP object. 6131c7c3c6aSMatthew Dillon * 614eb4d6a1bSKonstantin Belousov * This routine must ensure that no live duplicate is created for 615eb4d6a1bSKonstantin Belousov * the named object request, which is protected against by 616eb4d6a1bSKonstantin Belousov * holding the sw_alloc_sx lock in case handle != NULL. 61724a1cce3SDavid Greenman */ 618f5a12711SPoul-Henning Kamp static vm_object_t 6196cde7a16SDavid Greenman swap_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, 6203364c323SKonstantin Belousov vm_ooffset_t offset, struct ucred *cred) 62124a1cce3SDavid Greenman { 62224a1cce3SDavid Greenman vm_object_t object; 6232f7af3dbSAlan Cox 624eb4d6a1bSKonstantin Belousov if (handle != NULL) { 6251c7c3c6aSMatthew Dillon /* 6261c7c3c6aSMatthew Dillon * Reference existing named region or allocate new one. There 6271c7c3c6aSMatthew Dillon * should not be a race here against swp_pager_meta_build() 6281c7c3c6aSMatthew Dillon * as called from vm_page_remove() in regards to the lookup 6291c7c3c6aSMatthew Dillon * of the handle. 6301c7c3c6aSMatthew Dillon */ 6310cddd8f0SMatthew Dillon sx_xlock(&sw_alloc_sx); 6321c7c3c6aSMatthew Dillon object = vm_pager_object_lookup(NOBJLIST(handle), handle); 633b5e8f167SAlan Cox if (object == NULL) { 634eb4d6a1bSKonstantin Belousov object = swap_pager_alloc_init(handle, cred, size, 635eb4d6a1bSKonstantin Belousov offset); 636eb4d6a1bSKonstantin Belousov if (object != NULL) { 637eb4d6a1bSKonstantin Belousov TAILQ_INSERT_TAIL(NOBJLIST(object->handle), 638eb4d6a1bSKonstantin Belousov object, pager_object_list); 6393364c323SKonstantin Belousov } 64024a1cce3SDavid Greenman } 6410cddd8f0SMatthew Dillon sx_xunlock(&sw_alloc_sx); 64224a1cce3SDavid Greenman } else { 643eb4d6a1bSKonstantin Belousov object = swap_pager_alloc_init(handle, cred, size, offset); 64424a1cce3SDavid Greenman } 64524a1cce3SDavid Greenman return (object); 646df8bae1dSRodney W. Grimes } 647df8bae1dSRodney W. Grimes 64826f9a767SRodney W. Grimes /* 6491c7c3c6aSMatthew Dillon * SWAP_PAGER_DEALLOC() - remove swap metadata from object 6501c7c3c6aSMatthew Dillon * 6511c7c3c6aSMatthew Dillon * The swap backing for the object is destroyed. The code is 6521c7c3c6aSMatthew Dillon * designed such that we can reinstantiate it later, but this 6531c7c3c6aSMatthew Dillon * routine is typically called only when the entire object is 6541c7c3c6aSMatthew Dillon * about to be destroyed. 6551c7c3c6aSMatthew Dillon * 65615523cf7SKonstantin Belousov * The object must be locked. 65726f9a767SRodney W. Grimes */ 658df8bae1dSRodney W. Grimes static void 6592f249180SPoul-Henning Kamp swap_pager_dealloc(vm_object_t object) 66026f9a767SRodney W. Grimes { 6614dcc5c2dSMatthew Dillon 662eb4d6a1bSKonstantin Belousov VM_OBJECT_ASSERT_WLOCKED(object); 663eb4d6a1bSKonstantin Belousov KASSERT((object->flags & OBJ_DEAD) != 0, ("dealloc of reachable obj")); 664eb4d6a1bSKonstantin Belousov 66526f9a767SRodney W. Grimes /* 6661c7c3c6aSMatthew Dillon * Remove from list right away so lookups will fail if we block for 6671c7c3c6aSMatthew Dillon * pageout completion. 66826f9a767SRodney W. Grimes */ 669bd228075SAlan Cox if (object->handle != NULL) { 670eb4d6a1bSKonstantin Belousov VM_OBJECT_WUNLOCK(object); 671eb4d6a1bSKonstantin Belousov sx_xlock(&sw_alloc_sx); 672eb4d6a1bSKonstantin Belousov TAILQ_REMOVE(NOBJLIST(object->handle), object, 673eb4d6a1bSKonstantin Belousov pager_object_list); 674eb4d6a1bSKonstantin Belousov sx_xunlock(&sw_alloc_sx); 675eb4d6a1bSKonstantin Belousov VM_OBJECT_WLOCK(object); 676bd228075SAlan Cox } 6771c7c3c6aSMatthew Dillon 6781c7c3c6aSMatthew Dillon vm_object_pip_wait(object, "swpdea"); 6791c7c3c6aSMatthew Dillon 6801c7c3c6aSMatthew Dillon /* 6811c7c3c6aSMatthew Dillon * Free all remaining metadata. We only bother to free it from 6821c7c3c6aSMatthew Dillon * the swap meta data. We do not attempt to free swapblk's still 6831c7c3c6aSMatthew Dillon * associated with vm_page_t's for this object. We do not care 6841c7c3c6aSMatthew Dillon * if paging is still in progress on some objects. 6851c7c3c6aSMatthew Dillon */ 6861c7c3c6aSMatthew Dillon swp_pager_meta_free_all(object); 687e735691bSJohn Baldwin object->handle = NULL; 688e735691bSJohn Baldwin object->type = OBJT_DEAD; 6891c7c3c6aSMatthew Dillon } 6901c7c3c6aSMatthew Dillon 6911c7c3c6aSMatthew Dillon /************************************************************************ 6921c7c3c6aSMatthew Dillon * SWAP PAGER BITMAP ROUTINES * 6931c7c3c6aSMatthew Dillon ************************************************************************/ 6941c7c3c6aSMatthew Dillon 6951c7c3c6aSMatthew Dillon /* 6961c7c3c6aSMatthew Dillon * SWP_PAGER_GETSWAPSPACE() - allocate raw swap space 6971c7c3c6aSMatthew Dillon * 6981c7c3c6aSMatthew Dillon * Allocate swap for the requested number of pages. The starting 6991c7c3c6aSMatthew Dillon * swap block number (a page index) is returned or SWAPBLK_NONE 7001c7c3c6aSMatthew Dillon * if the allocation failed. 7011c7c3c6aSMatthew Dillon * 7021c7c3c6aSMatthew Dillon * Also has the side effect of advising that somebody made a mistake 7031c7c3c6aSMatthew Dillon * when they configured swap and didn't configure enough. 7041c7c3c6aSMatthew Dillon * 70515523cf7SKonstantin Belousov * This routine may not sleep. 7068f60c087SPoul-Henning Kamp * 7078f60c087SPoul-Henning Kamp * We allocate in round-robin fashion from the configured devices. 7081c7c3c6aSMatthew Dillon */ 709a5edd34aSPoul-Henning Kamp static daddr_t 7102f249180SPoul-Henning Kamp swp_pager_getswapspace(int npages) 7111c7c3c6aSMatthew Dillon { 7121c7c3c6aSMatthew Dillon daddr_t blk; 7138f60c087SPoul-Henning Kamp struct swdevt *sp; 7148f60c087SPoul-Henning Kamp int i; 7151c7c3c6aSMatthew Dillon 7168f60c087SPoul-Henning Kamp blk = SWAPBLK_NONE; 71720da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 7188f60c087SPoul-Henning Kamp sp = swdevhd; 7198f60c087SPoul-Henning Kamp for (i = 0; i < nswapdev; i++) { 7208f60c087SPoul-Henning Kamp if (sp == NULL) 7218f60c087SPoul-Henning Kamp sp = TAILQ_FIRST(&swtailq); 7228f60c087SPoul-Henning Kamp if (!(sp->sw_flags & SW_CLOSING)) { 7238f60c087SPoul-Henning Kamp blk = blist_alloc(sp->sw_blist, npages); 7248f60c087SPoul-Henning Kamp if (blk != SWAPBLK_NONE) { 7258f60c087SPoul-Henning Kamp blk += sp->sw_first; 7268f60c087SPoul-Henning Kamp sp->sw_used += npages; 727d05bc129SAlan Cox swap_pager_avail -= npages; 7288f60c087SPoul-Henning Kamp swp_sizecheck(); 7298f60c087SPoul-Henning Kamp swdevhd = TAILQ_NEXT(sp, sw_list); 730d05bc129SAlan Cox goto done; 7318f60c087SPoul-Henning Kamp } 7328f60c087SPoul-Henning Kamp } 7338f60c087SPoul-Henning Kamp sp = TAILQ_NEXT(sp, sw_list); 7348f60c087SPoul-Henning Kamp } 7352b0d37a4SMatthew Dillon if (swap_pager_full != 2) { 73620da9c2eSPoul-Henning Kamp printf("swap_pager_getswapspace(%d): failed\n", npages); 7372b0d37a4SMatthew Dillon swap_pager_full = 2; 73820d3034fSMatthew Dillon swap_pager_almost_full = 1; 7392b0d37a4SMatthew Dillon } 7408f60c087SPoul-Henning Kamp swdevhd = NULL; 741d05bc129SAlan Cox done: 742d05bc129SAlan Cox mtx_unlock(&sw_dev_mtx); 7431c7c3c6aSMatthew Dillon return (blk); 74426f9a767SRodney W. Grimes } 74526f9a767SRodney W. Grimes 746b3fed13eSDavid Schultz static int 747b3fed13eSDavid Schultz swp_pager_isondev(daddr_t blk, struct swdevt *sp) 7488f60c087SPoul-Henning Kamp { 7498f60c087SPoul-Henning Kamp 750b3fed13eSDavid Schultz return (blk >= sp->sw_first && blk < sp->sw_end); 7518f60c087SPoul-Henning Kamp } 7528f60c087SPoul-Henning Kamp 7534b03903aSPoul-Henning Kamp static void 7544b03903aSPoul-Henning Kamp swp_pager_strategy(struct buf *bp) 7554b03903aSPoul-Henning Kamp { 7564b03903aSPoul-Henning Kamp struct swdevt *sp; 7574b03903aSPoul-Henning Kamp 75820da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 7594b03903aSPoul-Henning Kamp TAILQ_FOREACH(sp, &swtailq, sw_list) { 7604b03903aSPoul-Henning Kamp if (bp->b_blkno >= sp->sw_first && bp->b_blkno < sp->sw_end) { 76120da9c2eSPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 7622cc718a1SKonstantin Belousov if ((sp->sw_flags & SW_UNMAPPED) != 0 && 7632cc718a1SKonstantin Belousov unmapped_buf_allowed) { 7642cc718a1SKonstantin Belousov bp->b_data = unmapped_buf; 7652cc718a1SKonstantin Belousov bp->b_offset = 0; 7662cc718a1SKonstantin Belousov } else { 7672cc718a1SKonstantin Belousov pmap_qenter((vm_offset_t)bp->b_data, 7682cc718a1SKonstantin Belousov &bp->b_pages[0], bp->b_bcount / PAGE_SIZE); 7692cc718a1SKonstantin Belousov } 7704b03903aSPoul-Henning Kamp sp->sw_strategy(bp, sp); 7714b03903aSPoul-Henning Kamp return; 7724b03903aSPoul-Henning Kamp } 7734b03903aSPoul-Henning Kamp } 77420da9c2eSPoul-Henning Kamp panic("Swapdev not found"); 7754b03903aSPoul-Henning Kamp } 7764b03903aSPoul-Henning Kamp 7778f60c087SPoul-Henning Kamp 77826f9a767SRodney W. Grimes /* 7791c7c3c6aSMatthew Dillon * SWP_PAGER_FREESWAPSPACE() - free raw swap space 7801c7c3c6aSMatthew Dillon * 7811c7c3c6aSMatthew Dillon * This routine returns the specified swap blocks back to the bitmap. 7821c7c3c6aSMatthew Dillon * 78315523cf7SKonstantin Belousov * This routine may not sleep. 78426f9a767SRodney W. Grimes */ 785a5edd34aSPoul-Henning Kamp static void 7868f60c087SPoul-Henning Kamp swp_pager_freeswapspace(daddr_t blk, int npages) 7870d94caffSDavid Greenman { 7888f60c087SPoul-Henning Kamp struct swdevt *sp; 78992da00bbSMatthew Dillon 7907645e885SAlan Cox mtx_lock(&sw_dev_mtx); 7917645e885SAlan Cox TAILQ_FOREACH(sp, &swtailq, sw_list) { 7927645e885SAlan Cox if (blk >= sp->sw_first && blk < sp->sw_end) { 79392da00bbSMatthew Dillon sp->sw_used -= npages; 79492da00bbSMatthew Dillon /* 7957645e885SAlan Cox * If we are attempting to stop swapping on 7967645e885SAlan Cox * this device, we don't want to mark any 7977645e885SAlan Cox * blocks free lest they be reused. 79892da00bbSMatthew Dillon */ 7997645e885SAlan Cox if ((sp->sw_flags & SW_CLOSING) == 0) { 8007645e885SAlan Cox blist_free(sp->sw_blist, blk - sp->sw_first, 8017645e885SAlan Cox npages); 8028f60c087SPoul-Henning Kamp swap_pager_avail += npages; 8031c7c3c6aSMatthew Dillon swp_sizecheck(); 80426f9a767SRodney W. Grimes } 8057645e885SAlan Cox mtx_unlock(&sw_dev_mtx); 8067645e885SAlan Cox return; 8077645e885SAlan Cox } 8087645e885SAlan Cox } 8097645e885SAlan Cox panic("Swapdev not found"); 8107645e885SAlan Cox } 8111c7c3c6aSMatthew Dillon 81226f9a767SRodney W. Grimes /* 8131c7c3c6aSMatthew Dillon * SWAP_PAGER_FREESPACE() - frees swap blocks associated with a page 8141c7c3c6aSMatthew Dillon * range within an object. 8151c7c3c6aSMatthew Dillon * 8161c7c3c6aSMatthew Dillon * This is a globally accessible routine. 8171c7c3c6aSMatthew Dillon * 8181c7c3c6aSMatthew Dillon * This routine removes swapblk assignments from swap metadata. 8191c7c3c6aSMatthew Dillon * 8201c7c3c6aSMatthew Dillon * The external callers of this routine typically have already destroyed 8211c7c3c6aSMatthew Dillon * or renamed vm_page_t's associated with this range in the object so 8221c7c3c6aSMatthew Dillon * we should be ok. 823c25673ffSAttilio Rao * 824c25673ffSAttilio Rao * The object must be locked. 82526f9a767SRodney W. Grimes */ 82626f9a767SRodney W. Grimes void 8272f249180SPoul-Henning Kamp swap_pager_freespace(vm_object_t object, vm_pindex_t start, vm_size_t size) 82826f9a767SRodney W. Grimes { 82923955314SAlfred Perlstein 8301c7c3c6aSMatthew Dillon swp_pager_meta_free(object, start, size); 8314dcc5c2dSMatthew Dillon } 8324dcc5c2dSMatthew Dillon 8334dcc5c2dSMatthew Dillon /* 8344dcc5c2dSMatthew Dillon * SWAP_PAGER_RESERVE() - reserve swap blocks in object 8354dcc5c2dSMatthew Dillon * 8364dcc5c2dSMatthew Dillon * Assigns swap blocks to the specified range within the object. The 83756ce850bSKonstantin Belousov * swap blocks are not zeroed. Any previous swap assignment is destroyed. 8384dcc5c2dSMatthew Dillon * 8394dcc5c2dSMatthew Dillon * Returns 0 on success, -1 on failure. 8404dcc5c2dSMatthew Dillon */ 8414dcc5c2dSMatthew Dillon int 8424dcc5c2dSMatthew Dillon swap_pager_reserve(vm_object_t object, vm_pindex_t start, vm_size_t size) 8434dcc5c2dSMatthew Dillon { 8444dcc5c2dSMatthew Dillon int n = 0; 8454dcc5c2dSMatthew Dillon daddr_t blk = SWAPBLK_NONE; 8464dcc5c2dSMatthew Dillon vm_pindex_t beg = start; /* save start index */ 8474dcc5c2dSMatthew Dillon 84889f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 8494dcc5c2dSMatthew Dillon while (size) { 8504dcc5c2dSMatthew Dillon if (n == 0) { 8514dcc5c2dSMatthew Dillon n = BLIST_MAX_ALLOC; 8524dcc5c2dSMatthew Dillon while ((blk = swp_pager_getswapspace(n)) == SWAPBLK_NONE) { 8534dcc5c2dSMatthew Dillon n >>= 1; 8544dcc5c2dSMatthew Dillon if (n == 0) { 8554dcc5c2dSMatthew Dillon swp_pager_meta_free(object, beg, start - beg); 85689f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 8574dcc5c2dSMatthew Dillon return (-1); 8584dcc5c2dSMatthew Dillon } 8594dcc5c2dSMatthew Dillon } 8604dcc5c2dSMatthew Dillon } 8614dcc5c2dSMatthew Dillon swp_pager_meta_build(object, start, blk); 8624dcc5c2dSMatthew Dillon --size; 8634dcc5c2dSMatthew Dillon ++start; 8644dcc5c2dSMatthew Dillon ++blk; 8654dcc5c2dSMatthew Dillon --n; 8664dcc5c2dSMatthew Dillon } 8674dcc5c2dSMatthew Dillon swp_pager_meta_free(object, start, n); 86889f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 8694dcc5c2dSMatthew Dillon return (0); 87026f9a767SRodney W. Grimes } 87126f9a767SRodney W. Grimes 8720a47b48bSJohn Dyson /* 8731c7c3c6aSMatthew Dillon * SWAP_PAGER_COPY() - copy blocks from source pager to destination pager 8741c7c3c6aSMatthew Dillon * and destroy the source. 8751c7c3c6aSMatthew Dillon * 8761c7c3c6aSMatthew Dillon * Copy any valid swapblks from the source to the destination. In 8771c7c3c6aSMatthew Dillon * cases where both the source and destination have a valid swapblk, 8781c7c3c6aSMatthew Dillon * we keep the destination's. 8791c7c3c6aSMatthew Dillon * 88015523cf7SKonstantin Belousov * This routine is allowed to sleep. It may sleep allocating metadata 8811c7c3c6aSMatthew Dillon * indirectly through swp_pager_meta_build() or if paging is still in 8821c7c3c6aSMatthew Dillon * progress on the source. 8831c7c3c6aSMatthew Dillon * 8841c7c3c6aSMatthew Dillon * The source object contains no vm_page_t's (which is just as well) 8851c7c3c6aSMatthew Dillon * 8861c7c3c6aSMatthew Dillon * The source object is of type OBJT_SWAP. 8871c7c3c6aSMatthew Dillon * 88815523cf7SKonstantin Belousov * The source and destination objects must be locked. 88915523cf7SKonstantin Belousov * Both object locks may temporarily be released. 89026f9a767SRodney W. Grimes */ 89126f9a767SRodney W. Grimes void 8922f249180SPoul-Henning Kamp swap_pager_copy(vm_object_t srcobject, vm_object_t dstobject, 8932f249180SPoul-Henning Kamp vm_pindex_t offset, int destroysource) 89426f9a767SRodney W. Grimes { 895a316d390SJohn Dyson vm_pindex_t i; 8964dcc5c2dSMatthew Dillon 89789f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(srcobject); 89889f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(dstobject); 8990cddd8f0SMatthew Dillon 90026f9a767SRodney W. Grimes /* 9011c7c3c6aSMatthew Dillon * If destroysource is set, we remove the source object from the 9021c7c3c6aSMatthew Dillon * swap_pager internal queue now. 90326f9a767SRodney W. Grimes */ 904eb4d6a1bSKonstantin Belousov if (destroysource && srcobject->handle != NULL) { 905eb4d6a1bSKonstantin Belousov vm_object_pip_add(srcobject, 1); 906eb4d6a1bSKonstantin Belousov VM_OBJECT_WUNLOCK(srcobject); 907eb4d6a1bSKonstantin Belousov vm_object_pip_add(dstobject, 1); 908eb4d6a1bSKonstantin Belousov VM_OBJECT_WUNLOCK(dstobject); 909eb4d6a1bSKonstantin Belousov sx_xlock(&sw_alloc_sx); 910eb4d6a1bSKonstantin Belousov TAILQ_REMOVE(NOBJLIST(srcobject->handle), srcobject, 911eb4d6a1bSKonstantin Belousov pager_object_list); 912eb4d6a1bSKonstantin Belousov sx_xunlock(&sw_alloc_sx); 913eb4d6a1bSKonstantin Belousov VM_OBJECT_WLOCK(dstobject); 914eb4d6a1bSKonstantin Belousov vm_object_pip_wakeup(dstobject); 915eb4d6a1bSKonstantin Belousov VM_OBJECT_WLOCK(srcobject); 916eb4d6a1bSKonstantin Belousov vm_object_pip_wakeup(srcobject); 917bd228075SAlan Cox } 91826f9a767SRodney W. Grimes 9191c7c3c6aSMatthew Dillon /* 9201c7c3c6aSMatthew Dillon * transfer source to destination. 9211c7c3c6aSMatthew Dillon */ 9221c7c3c6aSMatthew Dillon for (i = 0; i < dstobject->size; ++i) { 9231c7c3c6aSMatthew Dillon daddr_t dstaddr; 9241c7c3c6aSMatthew Dillon 9251c7c3c6aSMatthew Dillon /* 9261c7c3c6aSMatthew Dillon * Locate (without changing) the swapblk on the destination, 9271c7c3c6aSMatthew Dillon * unless it is invalid in which case free it silently, or 9281c7c3c6aSMatthew Dillon * if the destination is a resident page, in which case the 9291c7c3c6aSMatthew Dillon * source is thrown away. 9301c7c3c6aSMatthew Dillon */ 9311c7c3c6aSMatthew Dillon dstaddr = swp_pager_meta_ctl(dstobject, i, 0); 9321c7c3c6aSMatthew Dillon 9331c7c3c6aSMatthew Dillon if (dstaddr == SWAPBLK_NONE) { 9341c7c3c6aSMatthew Dillon /* 9351c7c3c6aSMatthew Dillon * Destination has no swapblk and is not resident, 9361c7c3c6aSMatthew Dillon * copy source. 9371c7c3c6aSMatthew Dillon */ 9381c7c3c6aSMatthew Dillon daddr_t srcaddr; 9391c7c3c6aSMatthew Dillon 9401c7c3c6aSMatthew Dillon srcaddr = swp_pager_meta_ctl( 9411c7c3c6aSMatthew Dillon srcobject, 9421c7c3c6aSMatthew Dillon i + offset, 9431c7c3c6aSMatthew Dillon SWM_POP 9441c7c3c6aSMatthew Dillon ); 9451c7c3c6aSMatthew Dillon 946ee3dc7d7SAlan Cox if (srcaddr != SWAPBLK_NONE) { 947c7c8dd7eSAlan Cox /* 948c7c8dd7eSAlan Cox * swp_pager_meta_build() can sleep. 949c7c8dd7eSAlan Cox */ 950c7c8dd7eSAlan Cox vm_object_pip_add(srcobject, 1); 95189f6b863SAttilio Rao VM_OBJECT_WUNLOCK(srcobject); 952c7c8dd7eSAlan Cox vm_object_pip_add(dstobject, 1); 9534dcc5c2dSMatthew Dillon swp_pager_meta_build(dstobject, i, srcaddr); 954c7c8dd7eSAlan Cox vm_object_pip_wakeup(dstobject); 95589f6b863SAttilio Rao VM_OBJECT_WLOCK(srcobject); 956c7c8dd7eSAlan Cox vm_object_pip_wakeup(srcobject); 957ee3dc7d7SAlan Cox } 9581c7c3c6aSMatthew Dillon } else { 9591c7c3c6aSMatthew Dillon /* 9601c7c3c6aSMatthew Dillon * Destination has valid swapblk or it is represented 9611c7c3c6aSMatthew Dillon * by a resident page. We destroy the sourceblock. 9621c7c3c6aSMatthew Dillon */ 9631c7c3c6aSMatthew Dillon 9641c7c3c6aSMatthew Dillon swp_pager_meta_ctl(srcobject, i + offset, SWM_FREE); 9651c7c3c6aSMatthew Dillon } 96626f9a767SRodney W. Grimes } 96726f9a767SRodney W. Grimes 96826f9a767SRodney W. Grimes /* 9691c7c3c6aSMatthew Dillon * Free left over swap blocks in source. 9701c7c3c6aSMatthew Dillon * 971763df3ecSPedro F. Giffuni * We have to revert the type to OBJT_DEFAULT so we do not accidentally 9721c7c3c6aSMatthew Dillon * double-remove the object from the swap queues. 97326f9a767SRodney W. Grimes */ 974c0877f10SJohn Dyson if (destroysource) { 9751c7c3c6aSMatthew Dillon swp_pager_meta_free_all(srcobject); 9761c7c3c6aSMatthew Dillon /* 9771c7c3c6aSMatthew Dillon * Reverting the type is not necessary, the caller is going 9781c7c3c6aSMatthew Dillon * to destroy srcobject directly, but I'm doing it here 979956f3135SPhilippe Charnier * for consistency since we've removed the object from its 9801c7c3c6aSMatthew Dillon * queues. 9811c7c3c6aSMatthew Dillon */ 9821c7c3c6aSMatthew Dillon srcobject->type = OBJT_DEFAULT; 983c0877f10SJohn Dyson } 98426f9a767SRodney W. Grimes } 98526f9a767SRodney W. Grimes 986df8bae1dSRodney W. Grimes /* 9871c7c3c6aSMatthew Dillon * SWAP_PAGER_HASPAGE() - determine if we have good backing store for 9881c7c3c6aSMatthew Dillon * the requested page. 9891c7c3c6aSMatthew Dillon * 9901c7c3c6aSMatthew Dillon * We determine whether good backing store exists for the requested 9911c7c3c6aSMatthew Dillon * page and return TRUE if it does, FALSE if it doesn't. 9921c7c3c6aSMatthew Dillon * 9931c7c3c6aSMatthew Dillon * If TRUE, we also try to determine how much valid, contiguous backing 994915d1b71SMark Johnston * store exists before and after the requested page. 995df8bae1dSRodney W. Grimes */ 9965ea4972cSAlan Cox static boolean_t 997915d1b71SMark Johnston swap_pager_haspage(vm_object_t object, vm_pindex_t pindex, int *before, 998915d1b71SMark Johnston int *after) 99926f9a767SRodney W. Grimes { 1000915d1b71SMark Johnston daddr_t blk, blk0; 1001915d1b71SMark Johnston int i; 100226f9a767SRodney W. Grimes 1003c25673ffSAttilio Rao VM_OBJECT_ASSERT_LOCKED(object); 1004915d1b71SMark Johnston 10051c7c3c6aSMatthew Dillon /* 10061c7c3c6aSMatthew Dillon * do we have good backing store at the requested index ? 10071c7c3c6aSMatthew Dillon */ 10081c7c3c6aSMatthew Dillon blk0 = swp_pager_meta_ctl(object, pindex, 0); 10094dcc5c2dSMatthew Dillon if (blk0 == SWAPBLK_NONE) { 10101c7c3c6aSMatthew Dillon if (before) 101124a1cce3SDavid Greenman *before = 0; 10121c7c3c6aSMatthew Dillon if (after) 101324a1cce3SDavid Greenman *after = 0; 101426f9a767SRodney W. Grimes return (FALSE); 101526f9a767SRodney W. Grimes } 101626f9a767SRodney W. Grimes 101726f9a767SRodney W. Grimes /* 10181c7c3c6aSMatthew Dillon * find backwards-looking contiguous good backing store 1019e47ed70bSJohn Dyson */ 10201c7c3c6aSMatthew Dillon if (before != NULL) { 1021915d1b71SMark Johnston for (i = 1; i < SWB_NPAGES; i++) { 10221c7c3c6aSMatthew Dillon if (i > pindex) 10231c7c3c6aSMatthew Dillon break; 10241c7c3c6aSMatthew Dillon blk = swp_pager_meta_ctl(object, pindex - i, 0); 10251c7c3c6aSMatthew Dillon if (blk != blk0 - i) 10261c7c3c6aSMatthew Dillon break; 1027ffc82b0aSJohn Dyson } 1028915d1b71SMark Johnston *before = i - 1; 102926f9a767SRodney W. Grimes } 103026f9a767SRodney W. Grimes 103126f9a767SRodney W. Grimes /* 10321c7c3c6aSMatthew Dillon * find forward-looking contiguous good backing store 103326f9a767SRodney W. Grimes */ 10341c7c3c6aSMatthew Dillon if (after != NULL) { 1035915d1b71SMark Johnston for (i = 1; i < SWB_NPAGES; i++) { 10361c7c3c6aSMatthew Dillon blk = swp_pager_meta_ctl(object, pindex + i, 0); 10371c7c3c6aSMatthew Dillon if (blk != blk0 + i) 10381c7c3c6aSMatthew Dillon break; 103926f9a767SRodney W. Grimes } 1040915d1b71SMark Johnston *after = i - 1; 10411c7c3c6aSMatthew Dillon } 10421c7c3c6aSMatthew Dillon return (TRUE); 10431c7c3c6aSMatthew Dillon } 10441c7c3c6aSMatthew Dillon 10451c7c3c6aSMatthew Dillon /* 10461c7c3c6aSMatthew Dillon * SWAP_PAGER_PAGE_UNSWAPPED() - remove swap backing store related to page 10471c7c3c6aSMatthew Dillon * 10481c7c3c6aSMatthew Dillon * This removes any associated swap backing store, whether valid or 10491c7c3c6aSMatthew Dillon * not, from the page. 10501c7c3c6aSMatthew Dillon * 10511c7c3c6aSMatthew Dillon * This routine is typically called when a page is made dirty, at 10521c7c3c6aSMatthew Dillon * which point any associated swap can be freed. MADV_FREE also 10531c7c3c6aSMatthew Dillon * calls us in a special-case situation 10541c7c3c6aSMatthew Dillon * 10551c7c3c6aSMatthew Dillon * NOTE!!! If the page is clean and the swap was valid, the caller 10561c7c3c6aSMatthew Dillon * should make the page dirty before calling this routine. This routine 10571c7c3c6aSMatthew Dillon * does NOT change the m->dirty status of the page. Also: MADV_FREE 10581c7c3c6aSMatthew Dillon * depends on it. 10591c7c3c6aSMatthew Dillon * 106015523cf7SKonstantin Belousov * This routine may not sleep. 1061c25673ffSAttilio Rao * 1062c25673ffSAttilio Rao * The object containing the page must be locked. 10631c7c3c6aSMatthew Dillon */ 10641c7c3c6aSMatthew Dillon static void 10652f249180SPoul-Henning Kamp swap_pager_unswapped(vm_page_t m) 10661c7c3c6aSMatthew Dillon { 10672f249180SPoul-Henning Kamp 10681c7c3c6aSMatthew Dillon swp_pager_meta_ctl(m->object, m->pindex, SWM_FREE); 10691c7c3c6aSMatthew Dillon } 10701c7c3c6aSMatthew Dillon 10711c7c3c6aSMatthew Dillon /* 1072915d1b71SMark Johnston * swap_pager_getpages() - bring pages in from swap 10731c7c3c6aSMatthew Dillon * 1074915d1b71SMark Johnston * Attempt to page in the pages in array "m" of length "count". The caller 1075915d1b71SMark Johnston * may optionally specify that additional pages preceding and succeeding 1076915d1b71SMark Johnston * the specified range be paged in. The number of such pages is returned 1077915d1b71SMark Johnston * in the "rbehind" and "rahead" parameters, and they will be in the 1078915d1b71SMark Johnston * inactive queue upon return. 10791c7c3c6aSMatthew Dillon * 1080915d1b71SMark Johnston * The pages in "m" must be busied and will remain busied upon return. 10811c7c3c6aSMatthew Dillon */ 1082f708ef1bSPoul-Henning Kamp static int 1083b0cd2017SGleb Smirnoff swap_pager_getpages(vm_object_t object, vm_page_t *m, int count, int *rbehind, 1084b0cd2017SGleb Smirnoff int *rahead) 1085df8bae1dSRodney W. Grimes { 10861c7c3c6aSMatthew Dillon struct buf *bp; 1087915d1b71SMark Johnston vm_page_t mpred, msucc, p; 1088915d1b71SMark Johnston vm_pindex_t pindex; 10891c7c3c6aSMatthew Dillon daddr_t blk; 1090dd9cb6daSMark Johnston int i, j, maxahead, maxbehind, reqcount, shift; 10910d94caffSDavid Greenman 1092915d1b71SMark Johnston reqcount = count; 10931c7c3c6aSMatthew Dillon 109489f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 10951c7c3c6aSMatthew Dillon bp = getpbuf(&nsw_rcount); 1096915d1b71SMark Johnston VM_OBJECT_WLOCK(object); 109726f9a767SRodney W. Grimes 1098dd9cb6daSMark Johnston if (!swap_pager_haspage(object, m[0]->pindex, &maxbehind, &maxahead)) { 1099915d1b71SMark Johnston relpbuf(bp, &nsw_rcount); 1100915d1b71SMark Johnston return (VM_PAGER_FAIL); 1101915d1b71SMark Johnston } 1102915d1b71SMark Johnston 1103915d1b71SMark Johnston /* 1104915d1b71SMark Johnston * Clip the readahead and readbehind ranges to exclude resident pages. 1105915d1b71SMark Johnston */ 1106915d1b71SMark Johnston if (rahead != NULL) { 1107dd9cb6daSMark Johnston KASSERT(reqcount - 1 <= maxahead, 1108915d1b71SMark Johnston ("page count %d extends beyond swap block", reqcount)); 1109dd9cb6daSMark Johnston *rahead = imin(*rahead, maxahead - (reqcount - 1)); 1110915d1b71SMark Johnston pindex = m[reqcount - 1]->pindex; 1111915d1b71SMark Johnston msucc = TAILQ_NEXT(m[reqcount - 1], listq); 1112915d1b71SMark Johnston if (msucc != NULL && msucc->pindex - pindex - 1 < *rahead) 1113915d1b71SMark Johnston *rahead = msucc->pindex - pindex - 1; 1114915d1b71SMark Johnston } 1115915d1b71SMark Johnston if (rbehind != NULL) { 1116dd9cb6daSMark Johnston *rbehind = imin(*rbehind, maxbehind); 1117915d1b71SMark Johnston pindex = m[0]->pindex; 1118915d1b71SMark Johnston mpred = TAILQ_PREV(m[0], pglist, listq); 1119915d1b71SMark Johnston if (mpred != NULL && pindex - mpred->pindex - 1 < *rbehind) 1120915d1b71SMark Johnston *rbehind = pindex - mpred->pindex - 1; 1121915d1b71SMark Johnston } 1122915d1b71SMark Johnston 1123915d1b71SMark Johnston /* 1124915d1b71SMark Johnston * Allocate readahead and readbehind pages. 1125915d1b71SMark Johnston */ 1126915d1b71SMark Johnston shift = rbehind != NULL ? *rbehind : 0; 1127915d1b71SMark Johnston if (shift != 0) { 1128915d1b71SMark Johnston for (i = 1; i <= shift; i++) { 1129915d1b71SMark Johnston p = vm_page_alloc(object, m[0]->pindex - i, 11307667839aSAlan Cox VM_ALLOC_NORMAL); 1131915d1b71SMark Johnston if (p == NULL) { 1132915d1b71SMark Johnston /* Shift allocated pages to the left. */ 1133915d1b71SMark Johnston for (j = 0; j < i - 1; j++) 1134915d1b71SMark Johnston bp->b_pages[j] = 1135915d1b71SMark Johnston bp->b_pages[j + shift - i + 1]; 1136915d1b71SMark Johnston break; 1137915d1b71SMark Johnston } 1138915d1b71SMark Johnston bp->b_pages[shift - i] = p; 1139915d1b71SMark Johnston } 1140915d1b71SMark Johnston shift = i - 1; 1141915d1b71SMark Johnston *rbehind = shift; 1142915d1b71SMark Johnston } 1143915d1b71SMark Johnston for (i = 0; i < reqcount; i++) 1144915d1b71SMark Johnston bp->b_pages[i + shift] = m[i]; 1145915d1b71SMark Johnston if (rahead != NULL) { 1146915d1b71SMark Johnston for (i = 0; i < *rahead; i++) { 1147915d1b71SMark Johnston p = vm_page_alloc(object, 11487667839aSAlan Cox m[reqcount - 1]->pindex + i + 1, VM_ALLOC_NORMAL); 1149915d1b71SMark Johnston if (p == NULL) 1150915d1b71SMark Johnston break; 1151915d1b71SMark Johnston bp->b_pages[shift + reqcount + i] = p; 1152915d1b71SMark Johnston } 1153915d1b71SMark Johnston *rahead = i; 1154915d1b71SMark Johnston } 1155915d1b71SMark Johnston if (rbehind != NULL) 1156915d1b71SMark Johnston count += *rbehind; 1157915d1b71SMark Johnston if (rahead != NULL) 1158915d1b71SMark Johnston count += *rahead; 1159915d1b71SMark Johnston 1160915d1b71SMark Johnston vm_object_pip_add(object, count); 1161915d1b71SMark Johnston 1162915d1b71SMark Johnston for (i = 0; i < count; i++) 1163915d1b71SMark Johnston bp->b_pages[i]->oflags |= VPO_SWAPINPROG; 1164915d1b71SMark Johnston 1165915d1b71SMark Johnston pindex = bp->b_pages[0]->pindex; 1166915d1b71SMark Johnston blk = swp_pager_meta_ctl(object, pindex, 0); 1167915d1b71SMark Johnston KASSERT(blk != SWAPBLK_NONE, 1168915d1b71SMark Johnston ("no swap blocking containing %p(%jx)", object, (uintmax_t)pindex)); 1169915d1b71SMark Johnston 1170915d1b71SMark Johnston VM_OBJECT_WUNLOCK(object); 1171915d1b71SMark Johnston 1172915d1b71SMark Johnston bp->b_flags |= B_PAGING; 117321144e3bSPoul-Henning Kamp bp->b_iocmd = BIO_READ; 11741c7c3c6aSMatthew Dillon bp->b_iodone = swp_pager_async_iodone; 1175fdcc1cc0SJohn Baldwin bp->b_rcred = crhold(thread0.td_ucred); 1176fdcc1cc0SJohn Baldwin bp->b_wcred = crhold(thread0.td_ucred); 1177b0cd2017SGleb Smirnoff bp->b_blkno = blk; 1178b0cd2017SGleb Smirnoff bp->b_bcount = PAGE_SIZE * count; 1179b0cd2017SGleb Smirnoff bp->b_bufsize = PAGE_SIZE * count; 1180b0cd2017SGleb Smirnoff bp->b_npages = count; 1181915d1b71SMark Johnston bp->b_pgbefore = rbehind != NULL ? *rbehind : 0; 1182915d1b71SMark Johnston bp->b_pgafter = rahead != NULL ? *rahead : 0; 118326f9a767SRodney W. Grimes 118483c9dea1SGleb Smirnoff VM_CNT_INC(v_swapin); 118583c9dea1SGleb Smirnoff VM_CNT_ADD(v_swappgsin, count); 11861c7c3c6aSMatthew Dillon 11871c7c3c6aSMatthew Dillon /* 11881c7c3c6aSMatthew Dillon * perform the I/O. NOTE!!! bp cannot be considered valid after 11891c7c3c6aSMatthew Dillon * this point because we automatically release it on completion. 11901c7c3c6aSMatthew Dillon * Instead, we look at the one page we are interested in which we 11911c7c3c6aSMatthew Dillon * still hold a lock on even through the I/O completion. 11921c7c3c6aSMatthew Dillon * 11931c7c3c6aSMatthew Dillon * The other pages in our m[] array are also released on completion, 11941c7c3c6aSMatthew Dillon * so we cannot assume they are valid anymore either. 11951c7c3c6aSMatthew Dillon * 1196c37a77eeSPoul-Henning Kamp * NOTE: b_blkno is destroyed by the call to swapdev_strategy 11971c7c3c6aSMatthew Dillon */ 1198b890cb2cSPeter Wemm BUF_KERNPROC(bp); 11994b03903aSPoul-Henning Kamp swp_pager_strategy(bp); 120026f9a767SRodney W. Grimes 120126f9a767SRodney W. Grimes /* 1202915d1b71SMark Johnston * Wait for the pages we want to complete. VPO_SWAPINPROG is always 12031c7c3c6aSMatthew Dillon * cleared on completion. If an I/O error occurs, SWAPBLK_NONE 1204915d1b71SMark Johnston * is set in the metadata for each page in the request. 120526f9a767SRodney W. Grimes */ 120689f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 1207b0cd2017SGleb Smirnoff while ((m[0]->oflags & VPO_SWAPINPROG) != 0) { 1208b0cd2017SGleb Smirnoff m[0]->oflags |= VPO_SWAPSLEEP; 120983c9dea1SGleb Smirnoff VM_CNT_INC(v_intrans); 1210c7aebda8SAttilio Rao if (VM_OBJECT_SLEEP(object, &object->paging_in_progress, PSWP, 1211c7aebda8SAttilio Rao "swread", hz * 20)) { 12129bd86a98SBruce M Simpson printf( 1213c5690651SPoul-Henning Kamp "swap_pager: indefinite wait buffer: bufobj: %p, blkno: %jd, size: %ld\n", 1214c5690651SPoul-Henning Kamp bp->b_bufobj, (intmax_t)bp->b_blkno, bp->b_bcount); 12151c7c3c6aSMatthew Dillon } 12161b119d9dSDavid Greenman } 121726f9a767SRodney W. Grimes 121826f9a767SRodney W. Grimes /* 1219b0cd2017SGleb Smirnoff * If we had an unrecoverable read error pages will not be valid. 122026f9a767SRodney W. Grimes */ 1221915d1b71SMark Johnston for (i = 0; i < reqcount; i++) 1222b0cd2017SGleb Smirnoff if (m[i]->valid != VM_PAGE_BITS_ALL) 12231c7c3c6aSMatthew Dillon return (VM_PAGER_ERROR); 1224b0cd2017SGleb Smirnoff 12251c7c3c6aSMatthew Dillon return (VM_PAGER_OK); 12261c7c3c6aSMatthew Dillon 12271c7c3c6aSMatthew Dillon /* 12281c7c3c6aSMatthew Dillon * A final note: in a low swap situation, we cannot deallocate swap 12291c7c3c6aSMatthew Dillon * and mark a page dirty here because the caller is likely to mark 12301c7c3c6aSMatthew Dillon * the page clean when we return, causing the page to possibly revert 12311c7c3c6aSMatthew Dillon * to all-zero's later. 12321c7c3c6aSMatthew Dillon */ 1233df8bae1dSRodney W. Grimes } 1234df8bae1dSRodney W. Grimes 12351c7c3c6aSMatthew Dillon /* 123690effb23SGleb Smirnoff * swap_pager_getpages_async(): 123790effb23SGleb Smirnoff * 123890effb23SGleb Smirnoff * Right now this is emulation of asynchronous operation on top of 123990effb23SGleb Smirnoff * swap_pager_getpages(). 124090effb23SGleb Smirnoff */ 124190effb23SGleb Smirnoff static int 124290effb23SGleb Smirnoff swap_pager_getpages_async(vm_object_t object, vm_page_t *m, int count, 1243b0cd2017SGleb Smirnoff int *rbehind, int *rahead, pgo_getpages_iodone_t iodone, void *arg) 124490effb23SGleb Smirnoff { 124590effb23SGleb Smirnoff int r, error; 124690effb23SGleb Smirnoff 1247b0cd2017SGleb Smirnoff r = swap_pager_getpages(object, m, count, rbehind, rahead); 124890effb23SGleb Smirnoff VM_OBJECT_WUNLOCK(object); 124990effb23SGleb Smirnoff switch (r) { 125090effb23SGleb Smirnoff case VM_PAGER_OK: 125190effb23SGleb Smirnoff error = 0; 125290effb23SGleb Smirnoff break; 125390effb23SGleb Smirnoff case VM_PAGER_ERROR: 125490effb23SGleb Smirnoff error = EIO; 125590effb23SGleb Smirnoff break; 125690effb23SGleb Smirnoff case VM_PAGER_FAIL: 125790effb23SGleb Smirnoff error = EINVAL; 125890effb23SGleb Smirnoff break; 125990effb23SGleb Smirnoff default: 1260d9328101SGleb Smirnoff panic("unhandled swap_pager_getpages() error %d", r); 126190effb23SGleb Smirnoff } 126290effb23SGleb Smirnoff (iodone)(arg, m, count, error); 126390effb23SGleb Smirnoff VM_OBJECT_WLOCK(object); 126490effb23SGleb Smirnoff 126590effb23SGleb Smirnoff return (r); 126690effb23SGleb Smirnoff } 126790effb23SGleb Smirnoff 126890effb23SGleb Smirnoff /* 12691c7c3c6aSMatthew Dillon * swap_pager_putpages: 12701c7c3c6aSMatthew Dillon * 12711c7c3c6aSMatthew Dillon * Assign swap (if necessary) and initiate I/O on the specified pages. 12721c7c3c6aSMatthew Dillon * 12731c7c3c6aSMatthew Dillon * We support both OBJT_DEFAULT and OBJT_SWAP objects. DEFAULT objects 12741c7c3c6aSMatthew Dillon * are automatically converted to SWAP objects. 12751c7c3c6aSMatthew Dillon * 1276ea3aecf5SPeter Wemm * In a low memory situation we may block in VOP_STRATEGY(), but the new 12771c7c3c6aSMatthew Dillon * vm_page reservation system coupled with properly written VFS devices 12781c7c3c6aSMatthew Dillon * should ensure that no low-memory deadlock occurs. This is an area 12791c7c3c6aSMatthew Dillon * which needs work. 12801c7c3c6aSMatthew Dillon * 12811c7c3c6aSMatthew Dillon * The parent has N vm_object_pip_add() references prior to 12821c7c3c6aSMatthew Dillon * calling us and will remove references for rtvals[] that are 12831c7c3c6aSMatthew Dillon * not set to VM_PAGER_PEND. We need to remove the rest on I/O 12841c7c3c6aSMatthew Dillon * completion. 12851c7c3c6aSMatthew Dillon * 12861c7c3c6aSMatthew Dillon * The parent has soft-busy'd the pages it passes us and will unbusy 12871c7c3c6aSMatthew Dillon * those whos rtvals[] entry is not set to VM_PAGER_PEND on return. 12881c7c3c6aSMatthew Dillon * We need to unbusy the rest on I/O completion. 12891c7c3c6aSMatthew Dillon */ 1290d635a37fSWarner Losh static void 12912f249180SPoul-Henning Kamp swap_pager_putpages(vm_object_t object, vm_page_t *m, int count, 1292e065e87cSKonstantin Belousov int flags, int *rtvals) 1293df8bae1dSRodney W. Grimes { 1294e065e87cSKonstantin Belousov int i, n; 1295e065e87cSKonstantin Belousov boolean_t sync; 1296df8bae1dSRodney W. Grimes 12971c7c3c6aSMatthew Dillon if (count && m[0]->object != object) { 12987036145bSMaxim Konovalov panic("swap_pager_putpages: object mismatch %p/%p", 12991c7c3c6aSMatthew Dillon object, 13001c7c3c6aSMatthew Dillon m[0]->object 13011c7c3c6aSMatthew Dillon ); 13021c7c3c6aSMatthew Dillon } 1303ee3dc7d7SAlan Cox 13041c7c3c6aSMatthew Dillon /* 13051c7c3c6aSMatthew Dillon * Step 1 13061c7c3c6aSMatthew Dillon * 13071c7c3c6aSMatthew Dillon * Turn object into OBJT_SWAP 13081c7c3c6aSMatthew Dillon * check for bogus sysops 13091c7c3c6aSMatthew Dillon * force sync if not pageout process 13101c7c3c6aSMatthew Dillon */ 13114dcc5c2dSMatthew Dillon if (object->type != OBJT_SWAP) 13124dcc5c2dSMatthew Dillon swp_pager_meta_build(object, 0, SWAPBLK_NONE); 131389f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 1314e47ed70bSJohn Dyson 1315e065e87cSKonstantin Belousov n = 0; 1316e47ed70bSJohn Dyson if (curproc != pageproc) 1317e47ed70bSJohn Dyson sync = TRUE; 1318e065e87cSKonstantin Belousov else 1319e065e87cSKonstantin Belousov sync = (flags & VM_PAGER_PUT_SYNC) != 0; 132026f9a767SRodney W. Grimes 13211c7c3c6aSMatthew Dillon /* 13221c7c3c6aSMatthew Dillon * Step 2 13231c7c3c6aSMatthew Dillon * 13241c7c3c6aSMatthew Dillon * Assign swap blocks and issue I/O. We reallocate swap on the fly. 13251c7c3c6aSMatthew Dillon * The page is left dirty until the pageout operation completes 13261c7c3c6aSMatthew Dillon * successfully. 13271c7c3c6aSMatthew Dillon */ 13281c7c3c6aSMatthew Dillon for (i = 0; i < count; i += n) { 13291c7c3c6aSMatthew Dillon int j; 13301c7c3c6aSMatthew Dillon struct buf *bp; 1331a316d390SJohn Dyson daddr_t blk; 133226f9a767SRodney W. Grimes 1333df8bae1dSRodney W. Grimes /* 13341c7c3c6aSMatthew Dillon * Maximum I/O size is limited by a number of factors. 1335df8bae1dSRodney W. Grimes */ 13361c7c3c6aSMatthew Dillon n = min(BLIST_MAX_ALLOC, count - i); 1337327f4e83SMatthew Dillon n = min(n, nsw_cluster_max); 13381c7c3c6aSMatthew Dillon 133926f9a767SRodney W. Grimes /* 13401c7c3c6aSMatthew Dillon * Get biggest block of swap we can. If we fail, fall 13411c7c3c6aSMatthew Dillon * back and try to allocate a smaller block. Don't go 13421c7c3c6aSMatthew Dillon * overboard trying to allocate space if it would overly 13431c7c3c6aSMatthew Dillon * fragment swap. 134426f9a767SRodney W. Grimes */ 13451c7c3c6aSMatthew Dillon while ( 13461c7c3c6aSMatthew Dillon (blk = swp_pager_getswapspace(n)) == SWAPBLK_NONE && 13471c7c3c6aSMatthew Dillon n > 4 13481c7c3c6aSMatthew Dillon ) { 13491c7c3c6aSMatthew Dillon n >>= 1; 135026f9a767SRodney W. Grimes } 13511c7c3c6aSMatthew Dillon if (blk == SWAPBLK_NONE) { 13524dcc5c2dSMatthew Dillon for (j = 0; j < n; ++j) 13531c7c3c6aSMatthew Dillon rtvals[i+j] = VM_PAGER_FAIL; 13541c7c3c6aSMatthew Dillon continue; 135526f9a767SRodney W. Grimes } 135626f9a767SRodney W. Grimes 135726f9a767SRodney W. Grimes /* 13581c7c3c6aSMatthew Dillon * All I/O parameters have been satisfied, build the I/O 13591c7c3c6aSMatthew Dillon * request and assign the swap space. 136026f9a767SRodney W. Grimes */ 1361327f4e83SMatthew Dillon if (sync == TRUE) { 1362327f4e83SMatthew Dillon bp = getpbuf(&nsw_wcount_sync); 1363327f4e83SMatthew Dillon } else { 1364327f4e83SMatthew Dillon bp = getpbuf(&nsw_wcount_async); 136521144e3bSPoul-Henning Kamp bp->b_flags = B_ASYNC; 1366327f4e83SMatthew Dillon } 13675e04322aSPoul-Henning Kamp bp->b_flags |= B_PAGING; 1368912e4ae9SPoul-Henning Kamp bp->b_iocmd = BIO_WRITE; 136926f9a767SRodney W. Grimes 1370fdcc1cc0SJohn Baldwin bp->b_rcred = crhold(thread0.td_ucred); 1371fdcc1cc0SJohn Baldwin bp->b_wcred = crhold(thread0.td_ucred); 13721c7c3c6aSMatthew Dillon bp->b_bcount = PAGE_SIZE * n; 13731c7c3c6aSMatthew Dillon bp->b_bufsize = PAGE_SIZE * n; 13741c7c3c6aSMatthew Dillon bp->b_blkno = blk; 1375e47ed70bSJohn Dyson 137689f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 13771c7c3c6aSMatthew Dillon for (j = 0; j < n; ++j) { 13781c7c3c6aSMatthew Dillon vm_page_t mreq = m[i+j]; 13791c7c3c6aSMatthew Dillon 13801c7c3c6aSMatthew Dillon swp_pager_meta_build( 13811c7c3c6aSMatthew Dillon mreq->object, 13821c7c3c6aSMatthew Dillon mreq->pindex, 13834dcc5c2dSMatthew Dillon blk + j 13841c7c3c6aSMatthew Dillon ); 13857dbf82dcSMatthew Dillon vm_page_dirty(mreq); 13865786be7cSAlan Cox mreq->oflags |= VPO_SWAPINPROG; 13871c7c3c6aSMatthew Dillon bp->b_pages[j] = mreq; 13881c7c3c6aSMatthew Dillon } 138989f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 13901c7c3c6aSMatthew Dillon bp->b_npages = n; 1391a5296b05SJulian Elischer /* 1392a5296b05SJulian Elischer * Must set dirty range for NFS to work. 1393a5296b05SJulian Elischer */ 1394a5296b05SJulian Elischer bp->b_dirtyoff = 0; 1395a5296b05SJulian Elischer bp->b_dirtyend = bp->b_bcount; 13961c7c3c6aSMatthew Dillon 139783c9dea1SGleb Smirnoff VM_CNT_INC(v_swapout); 139883c9dea1SGleb Smirnoff VM_CNT_ADD(v_swappgsout, bp->b_npages); 139926f9a767SRodney W. Grimes 140026f9a767SRodney W. Grimes /* 140177923df2SAlan Cox * We unconditionally set rtvals[] to VM_PAGER_PEND so that we 140277923df2SAlan Cox * can call the async completion routine at the end of a 140377923df2SAlan Cox * synchronous I/O operation. Otherwise, our caller would 140477923df2SAlan Cox * perform duplicate unbusy and wakeup operations on the page 140577923df2SAlan Cox * and object, respectively. 140677923df2SAlan Cox */ 140777923df2SAlan Cox for (j = 0; j < n; j++) 140877923df2SAlan Cox rtvals[i + j] = VM_PAGER_PEND; 140977923df2SAlan Cox 141077923df2SAlan Cox /* 14111c7c3c6aSMatthew Dillon * asynchronous 14121c7c3c6aSMatthew Dillon * 1413c37a77eeSPoul-Henning Kamp * NOTE: b_blkno is destroyed by the call to swapdev_strategy 141426f9a767SRodney W. Grimes */ 14151c7c3c6aSMatthew Dillon if (sync == FALSE) { 14161c7c3c6aSMatthew Dillon bp->b_iodone = swp_pager_async_iodone; 141767812eacSKirk McKusick BUF_KERNPROC(bp); 14184b03903aSPoul-Henning Kamp swp_pager_strategy(bp); 14191c7c3c6aSMatthew Dillon continue; 142026f9a767SRodney W. Grimes } 1421e47ed70bSJohn Dyson 142226f9a767SRodney W. Grimes /* 14231c7c3c6aSMatthew Dillon * synchronous 14241c7c3c6aSMatthew Dillon * 1425c37a77eeSPoul-Henning Kamp * NOTE: b_blkno is destroyed by the call to swapdev_strategy 14261c7c3c6aSMatthew Dillon */ 14272c840b1fSAlan Cox bp->b_iodone = bdone; 14284b03903aSPoul-Henning Kamp swp_pager_strategy(bp); 14291c7c3c6aSMatthew Dillon 14301c7c3c6aSMatthew Dillon /* 143177923df2SAlan Cox * Wait for the sync I/O to complete. 143226f9a767SRodney W. Grimes */ 14332c840b1fSAlan Cox bwait(bp, PVM, "swwrt"); 143477923df2SAlan Cox 14351c7c3c6aSMatthew Dillon /* 14361c7c3c6aSMatthew Dillon * Now that we are through with the bp, we can call the 14371c7c3c6aSMatthew Dillon * normal async completion, which frees everything up. 14381c7c3c6aSMatthew Dillon */ 14391c7c3c6aSMatthew Dillon swp_pager_async_iodone(bp); 14401c7c3c6aSMatthew Dillon } 144189f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 14421c7c3c6aSMatthew Dillon } 14431c7c3c6aSMatthew Dillon 14441c7c3c6aSMatthew Dillon /* 14451c7c3c6aSMatthew Dillon * swp_pager_async_iodone: 14461c7c3c6aSMatthew Dillon * 14471c7c3c6aSMatthew Dillon * Completion routine for asynchronous reads and writes from/to swap. 14481c7c3c6aSMatthew Dillon * Also called manually by synchronous code to finish up a bp. 14491c7c3c6aSMatthew Dillon * 145015523cf7SKonstantin Belousov * This routine may not sleep. 14511c7c3c6aSMatthew Dillon */ 14521c7c3c6aSMatthew Dillon static void 14532f249180SPoul-Henning Kamp swp_pager_async_iodone(struct buf *bp) 14541c7c3c6aSMatthew Dillon { 14551c7c3c6aSMatthew Dillon int i; 14561c7c3c6aSMatthew Dillon vm_object_t object = NULL; 14571c7c3c6aSMatthew Dillon 14581c7c3c6aSMatthew Dillon /* 14591c7c3c6aSMatthew Dillon * report error 14601c7c3c6aSMatthew Dillon */ 1461c244d2deSPoul-Henning Kamp if (bp->b_ioflags & BIO_ERROR) { 14621c7c3c6aSMatthew Dillon printf( 14631c7c3c6aSMatthew Dillon "swap_pager: I/O error - %s failed; blkno %ld," 14641c7c3c6aSMatthew Dillon "size %ld, error %d\n", 146521144e3bSPoul-Henning Kamp ((bp->b_iocmd == BIO_READ) ? "pagein" : "pageout"), 14661c7c3c6aSMatthew Dillon (long)bp->b_blkno, 14671c7c3c6aSMatthew Dillon (long)bp->b_bcount, 14681c7c3c6aSMatthew Dillon bp->b_error 14691c7c3c6aSMatthew Dillon ); 14701c7c3c6aSMatthew Dillon } 14711c7c3c6aSMatthew Dillon 14721c7c3c6aSMatthew Dillon /* 147326f9a767SRodney W. Grimes * remove the mapping for kernel virtual 147426f9a767SRodney W. Grimes */ 1475fade8dd7SJeff Roberson if (buf_mapped(bp)) 14761c7c3c6aSMatthew Dillon pmap_qremove((vm_offset_t)bp->b_data, bp->b_npages); 1477fade8dd7SJeff Roberson else 1478fade8dd7SJeff Roberson bp->b_data = bp->b_kvabase; 147926f9a767SRodney W. Grimes 148033a609ecSAlan Cox if (bp->b_npages) { 148133a609ecSAlan Cox object = bp->b_pages[0]->object; 148289f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 148333a609ecSAlan Cox } 14842965a453SKip Macy 148526f9a767SRodney W. Grimes /* 14861c7c3c6aSMatthew Dillon * cleanup pages. If an error occurs writing to swap, we are in 14871c7c3c6aSMatthew Dillon * very serious trouble. If it happens to be a disk error, though, 14881c7c3c6aSMatthew Dillon * we may be able to recover by reassigning the swap later on. So 14891c7c3c6aSMatthew Dillon * in this case we remove the m->swapblk assignment for the page 14901c7c3c6aSMatthew Dillon * but do not free it in the rlist. The errornous block(s) are thus 14911c7c3c6aSMatthew Dillon * never reallocated as swap. Redirty the page and continue. 149226f9a767SRodney W. Grimes */ 14931c7c3c6aSMatthew Dillon for (i = 0; i < bp->b_npages; ++i) { 14941c7c3c6aSMatthew Dillon vm_page_t m = bp->b_pages[i]; 1495e47ed70bSJohn Dyson 14965786be7cSAlan Cox m->oflags &= ~VPO_SWAPINPROG; 1497c7aebda8SAttilio Rao if (m->oflags & VPO_SWAPSLEEP) { 1498c7aebda8SAttilio Rao m->oflags &= ~VPO_SWAPSLEEP; 1499c7aebda8SAttilio Rao wakeup(&object->paging_in_progress); 1500c7aebda8SAttilio Rao } 1501e47ed70bSJohn Dyson 1502c244d2deSPoul-Henning Kamp if (bp->b_ioflags & BIO_ERROR) { 1503ffc82b0aSJohn Dyson /* 15041c7c3c6aSMatthew Dillon * If an error occurs I'd love to throw the swapblk 15051c7c3c6aSMatthew Dillon * away without freeing it back to swapspace, so it 15061c7c3c6aSMatthew Dillon * can never be used again. But I can't from an 15071c7c3c6aSMatthew Dillon * interrupt. 1508ffc82b0aSJohn Dyson */ 150921144e3bSPoul-Henning Kamp if (bp->b_iocmd == BIO_READ) { 15101c7c3c6aSMatthew Dillon /* 15111c7c3c6aSMatthew Dillon * NOTE: for reads, m->dirty will probably 1512956f3135SPhilippe Charnier * be overridden by the original caller of 15131c7c3c6aSMatthew Dillon * getpages so don't play cute tricks here. 15141c7c3c6aSMatthew Dillon */ 15151c7c3c6aSMatthew Dillon m->valid = 0; 15161c7c3c6aSMatthew Dillon } else { 15171c7c3c6aSMatthew Dillon /* 15181c7c3c6aSMatthew Dillon * If a write error occurs, reactivate page 15191c7c3c6aSMatthew Dillon * so it doesn't clog the inactive list, 15201c7c3c6aSMatthew Dillon * then finish the I/O. 15211c7c3c6aSMatthew Dillon */ 15227dbf82dcSMatthew Dillon vm_page_dirty(m); 15233c4a2440SAlan Cox vm_page_lock(m); 15241c7c3c6aSMatthew Dillon vm_page_activate(m); 15253c4a2440SAlan Cox vm_page_unlock(m); 1526c7aebda8SAttilio Rao vm_page_sunbusy(m); 15271c7c3c6aSMatthew Dillon } 152821144e3bSPoul-Henning Kamp } else if (bp->b_iocmd == BIO_READ) { 15291c7c3c6aSMatthew Dillon /* 15301c7c3c6aSMatthew Dillon * NOTE: for reads, m->dirty will probably be 1531956f3135SPhilippe Charnier * overridden by the original caller of getpages so 15321c7c3c6aSMatthew Dillon * we cannot set them in order to free the underlying 15331c7c3c6aSMatthew Dillon * swap in a low-swap situation. I don't think we'd 15341c7c3c6aSMatthew Dillon * want to do that anyway, but it was an optimization 15351c7c3c6aSMatthew Dillon * that existed in the old swapper for a time before 15361c7c3c6aSMatthew Dillon * it got ripped out due to precisely this problem. 15371c7c3c6aSMatthew Dillon */ 1538016a3c93SAlan Cox KASSERT(!pmap_page_is_mapped(m), 1539016a3c93SAlan Cox ("swp_pager_async_iodone: page %p is mapped", m)); 1540016a3c93SAlan Cox KASSERT(m->dirty == 0, 1541016a3c93SAlan Cox ("swp_pager_async_iodone: page %p is dirty", m)); 1542915d1b71SMark Johnston 1543b0cd2017SGleb Smirnoff m->valid = VM_PAGE_BITS_ALL; 1544915d1b71SMark Johnston if (i < bp->b_pgbefore || 1545915d1b71SMark Johnston i >= bp->b_npages - bp->b_pgafter) 1546915d1b71SMark Johnston vm_page_readahead_finish(m); 15471c7c3c6aSMatthew Dillon } else { 15481c7c3c6aSMatthew Dillon /* 1549016a3c93SAlan Cox * For write success, clear the dirty 15501c7c3c6aSMatthew Dillon * status, then finish the I/O ( which decrements the 15511c7c3c6aSMatthew Dillon * busy count and possibly wakes waiter's up ). 1552ebcddc72SAlan Cox * A page is only written to swap after a period of 1553ebcddc72SAlan Cox * inactivity. Therefore, we do not expect it to be 1554ebcddc72SAlan Cox * reused. 15551c7c3c6aSMatthew Dillon */ 15566031c68dSAlan Cox KASSERT(!pmap_page_is_write_mapped(m), 1557016a3c93SAlan Cox ("swp_pager_async_iodone: page %p is not write" 1558016a3c93SAlan Cox " protected", m)); 1559c52e7044SAlan Cox vm_page_undirty(m); 15603c4a2440SAlan Cox vm_page_lock(m); 1561ebcddc72SAlan Cox vm_page_deactivate_noreuse(m); 15622965a453SKip Macy vm_page_unlock(m); 1563ebcddc72SAlan Cox vm_page_sunbusy(m); 15643c4a2440SAlan Cox } 15653c4a2440SAlan Cox } 156626f9a767SRodney W. Grimes 15671c7c3c6aSMatthew Dillon /* 15681c7c3c6aSMatthew Dillon * adjust pip. NOTE: the original parent may still have its own 15691c7c3c6aSMatthew Dillon * pip refs on the object. 15701c7c3c6aSMatthew Dillon */ 15710d420ad3SAlan Cox if (object != NULL) { 15721c7c3c6aSMatthew Dillon vm_object_pip_wakeupn(object, bp->b_npages); 157389f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 15740d420ad3SAlan Cox } 157526f9a767SRodney W. Grimes 15761c7c3c6aSMatthew Dillon /* 1577100650deSOlivier Houchard * swapdev_strategy() manually sets b_vp and b_bufobj before calling 1578100650deSOlivier Houchard * bstrategy(). Set them back to NULL now we're done with it, or we'll 1579100650deSOlivier Houchard * trigger a KASSERT in relpbuf(). 1580100650deSOlivier Houchard */ 1581100650deSOlivier Houchard if (bp->b_vp) { 1582100650deSOlivier Houchard bp->b_vp = NULL; 1583100650deSOlivier Houchard bp->b_bufobj = NULL; 1584100650deSOlivier Houchard } 1585100650deSOlivier Houchard /* 15861c7c3c6aSMatthew Dillon * release the physical I/O buffer 15871c7c3c6aSMatthew Dillon */ 1588327f4e83SMatthew Dillon relpbuf( 1589327f4e83SMatthew Dillon bp, 159021144e3bSPoul-Henning Kamp ((bp->b_iocmd == BIO_READ) ? &nsw_rcount : 1591327f4e83SMatthew Dillon ((bp->b_flags & B_ASYNC) ? 1592327f4e83SMatthew Dillon &nsw_wcount_async : 1593327f4e83SMatthew Dillon &nsw_wcount_sync 1594327f4e83SMatthew Dillon ) 1595327f4e83SMatthew Dillon ) 1596327f4e83SMatthew Dillon ); 159726f9a767SRodney W. Grimes } 15981c7c3c6aSMatthew Dillon 159992da00bbSMatthew Dillon /* 160092da00bbSMatthew Dillon * swap_pager_isswapped: 160192da00bbSMatthew Dillon * 160292da00bbSMatthew Dillon * Return 1 if at least one page in the given object is paged 160392da00bbSMatthew Dillon * out to the given swap device. 160492da00bbSMatthew Dillon * 160515523cf7SKonstantin Belousov * This routine may not sleep. 160692da00bbSMatthew Dillon */ 16078f60c087SPoul-Henning Kamp int 16088f60c087SPoul-Henning Kamp swap_pager_isswapped(vm_object_t object, struct swdevt *sp) 16098f60c087SPoul-Henning Kamp { 161092da00bbSMatthew Dillon daddr_t index = 0; 161192da00bbSMatthew Dillon int bcount; 161292da00bbSMatthew Dillon int i; 161392da00bbSMatthew Dillon 161489f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(object); 1615f6bcadc4SDavid Schultz if (object->type != OBJT_SWAP) 1616f6bcadc4SDavid Schultz return (0); 1617f6bcadc4SDavid Schultz 1618b3fed13eSDavid Schultz mtx_lock(&swhash_mtx); 161992da00bbSMatthew Dillon for (bcount = 0; bcount < object->un_pager.swp.swp_bcount; bcount++) { 162092da00bbSMatthew Dillon struct swblock *swap; 162192da00bbSMatthew Dillon 162292da00bbSMatthew Dillon if ((swap = *swp_pager_hash(object, index)) != NULL) { 162392da00bbSMatthew Dillon for (i = 0; i < SWAP_META_PAGES; ++i) { 1624b3fed13eSDavid Schultz if (swp_pager_isondev(swap->swb_pages[i], sp)) { 16257827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 1626b3fed13eSDavid Schultz return (1); 162792da00bbSMatthew Dillon } 162892da00bbSMatthew Dillon } 16297827d9b0SAlan Cox } 163092da00bbSMatthew Dillon index += SWAP_META_PAGES; 163192da00bbSMatthew Dillon } 1632b3fed13eSDavid Schultz mtx_unlock(&swhash_mtx); 1633b3fed13eSDavid Schultz return (0); 163492da00bbSMatthew Dillon } 163592da00bbSMatthew Dillon 1636b1fd102eSMark Johnston int 1637b1fd102eSMark Johnston swap_pager_nswapdev(void) 1638b1fd102eSMark Johnston { 1639b1fd102eSMark Johnston 1640b1fd102eSMark Johnston return (nswapdev); 1641b1fd102eSMark Johnston } 1642b1fd102eSMark Johnston 164392da00bbSMatthew Dillon /* 164492da00bbSMatthew Dillon * SWP_PAGER_FORCE_PAGEIN() - force a swap block to be paged in 164592da00bbSMatthew Dillon * 1646ebcddc72SAlan Cox * This routine dissociates the page at the given index within an object 1647ebcddc72SAlan Cox * from its backing store, paging it in if it does not reside in memory. 1648ebcddc72SAlan Cox * If the page is paged in, it is marked dirty and placed in the laundry 1649ebcddc72SAlan Cox * queue. The page is marked dirty because it no longer has backing 1650ebcddc72SAlan Cox * store. It is placed in the laundry queue because it has not been 1651ebcddc72SAlan Cox * accessed recently. Otherwise, it would already reside in memory. 1652ebcddc72SAlan Cox * 1653ebcddc72SAlan Cox * We also attempt to swap in all other pages in the swap block. 1654ebcddc72SAlan Cox * However, we only guarantee that the one at the specified index is 165592da00bbSMatthew Dillon * paged in. 165692da00bbSMatthew Dillon * 165792da00bbSMatthew Dillon * XXX - The code to page the whole block in doesn't work, so we 165892da00bbSMatthew Dillon * revert to the one-by-one behavior for now. Sigh. 165992da00bbSMatthew Dillon */ 166062a59e8fSWarner Losh static inline void 1661b3fed13eSDavid Schultz swp_pager_force_pagein(vm_object_t object, vm_pindex_t pindex) 166292da00bbSMatthew Dillon { 166392da00bbSMatthew Dillon vm_page_t m; 166492da00bbSMatthew Dillon 166592da00bbSMatthew Dillon vm_object_pip_add(object, 1); 16665944de8eSKonstantin Belousov m = vm_page_grab(object, pindex, VM_ALLOC_NORMAL); 166792da00bbSMatthew Dillon if (m->valid == VM_PAGE_BITS_ALL) { 16680d8243ccSAttilio Rao vm_object_pip_wakeup(object); 166992da00bbSMatthew Dillon vm_page_dirty(m); 1670d061cdd5SAlan Cox vm_page_lock(m); 1671d061cdd5SAlan Cox vm_page_activate(m); 16722965a453SKip Macy vm_page_unlock(m); 1673c7aebda8SAttilio Rao vm_page_xunbusy(m); 167492da00bbSMatthew Dillon vm_pager_page_unswapped(m); 167592da00bbSMatthew Dillon return; 167692da00bbSMatthew Dillon } 167792da00bbSMatthew Dillon 1678b0cd2017SGleb Smirnoff if (swap_pager_getpages(object, &m, 1, NULL, NULL) != VM_PAGER_OK) 167992da00bbSMatthew Dillon panic("swap_pager_force_pagein: read from swap failed");/*XXX*/ 16800d8243ccSAttilio Rao vm_object_pip_wakeup(object); 168192da00bbSMatthew Dillon vm_page_dirty(m); 1682db1f085eSAlan Cox vm_page_lock(m); 1683ebcddc72SAlan Cox vm_page_launder(m); 16842965a453SKip Macy vm_page_unlock(m); 1685c7aebda8SAttilio Rao vm_page_xunbusy(m); 168692da00bbSMatthew Dillon vm_pager_page_unswapped(m); 168792da00bbSMatthew Dillon } 168892da00bbSMatthew Dillon 168992da00bbSMatthew Dillon /* 169092da00bbSMatthew Dillon * swap_pager_swapoff: 169192da00bbSMatthew Dillon * 169292da00bbSMatthew Dillon * Page in all of the pages that have been paged out to the 169392da00bbSMatthew Dillon * given device. The corresponding blocks in the bitmap must be 169492da00bbSMatthew Dillon * marked as allocated and the device must be flagged SW_CLOSING. 169592da00bbSMatthew Dillon * There may be no processes swapped out to the device. 169692da00bbSMatthew Dillon * 169792da00bbSMatthew Dillon * This routine may block. 169892da00bbSMatthew Dillon */ 1699e9c0cc15SPoul-Henning Kamp static void 1700b3fed13eSDavid Schultz swap_pager_swapoff(struct swdevt *sp) 170192da00bbSMatthew Dillon { 170292da00bbSMatthew Dillon struct swblock *swap; 170398150664SKonstantin Belousov vm_object_t locked_obj, object; 170498150664SKonstantin Belousov vm_pindex_t pindex; 17058bc61209SDavid Schultz int i, j, retries; 170692da00bbSMatthew Dillon 170704533e1eSKonstantin Belousov sx_assert(&swdev_syscall_lock, SA_XLOCKED); 170892da00bbSMatthew Dillon 17098bc61209SDavid Schultz retries = 0; 171098150664SKonstantin Belousov locked_obj = NULL; 171192da00bbSMatthew Dillon full_rescan: 1712b3fed13eSDavid Schultz mtx_lock(&swhash_mtx); 171392da00bbSMatthew Dillon for (i = 0; i <= swhash_mask; i++) { /* '<=' is correct here */ 171492da00bbSMatthew Dillon restart: 1715b3fed13eSDavid Schultz for (swap = swhash[i]; swap != NULL; swap = swap->swb_hnext) { 171698150664SKonstantin Belousov object = swap->swb_object; 171798150664SKonstantin Belousov pindex = swap->swb_index; 171892da00bbSMatthew Dillon for (j = 0; j < SWAP_META_PAGES; ++j) { 171998150664SKonstantin Belousov if (!swp_pager_isondev(swap->swb_pages[j], sp)) 172098150664SKonstantin Belousov continue; 172198150664SKonstantin Belousov if (locked_obj != object) { 172298150664SKonstantin Belousov if (locked_obj != NULL) 172398150664SKonstantin Belousov VM_OBJECT_WUNLOCK(locked_obj); 172498150664SKonstantin Belousov locked_obj = object; 172589f6b863SAttilio Rao if (!VM_OBJECT_TRYWLOCK(object)) { 1726b3fed13eSDavid Schultz mtx_unlock(&swhash_mtx); 172798150664SKonstantin Belousov /* Depends on type-stability. */ 172898150664SKonstantin Belousov VM_OBJECT_WLOCK(object); 172998150664SKonstantin Belousov mtx_lock(&swhash_mtx); 173098150664SKonstantin Belousov goto restart; 173198150664SKonstantin Belousov } 173298150664SKonstantin Belousov } 173398150664SKonstantin Belousov MPASS(locked_obj == object); 173498150664SKonstantin Belousov mtx_unlock(&swhash_mtx); 173598150664SKonstantin Belousov swp_pager_force_pagein(object, pindex + j); 1736b3fed13eSDavid Schultz mtx_lock(&swhash_mtx); 173792da00bbSMatthew Dillon goto restart; 173892da00bbSMatthew Dillon } 1739b3fed13eSDavid Schultz } 1740b3fed13eSDavid Schultz } 1741d536c58fSAlan Cox mtx_unlock(&swhash_mtx); 174298150664SKonstantin Belousov if (locked_obj != NULL) { 174398150664SKonstantin Belousov VM_OBJECT_WUNLOCK(locked_obj); 174498150664SKonstantin Belousov locked_obj = NULL; 174598150664SKonstantin Belousov } 17468bc61209SDavid Schultz if (sp->sw_used) { 174792da00bbSMatthew Dillon /* 17488bc61209SDavid Schultz * Objects may be locked or paging to the device being 17498bc61209SDavid Schultz * removed, so we will miss their pages and need to 17508bc61209SDavid Schultz * make another pass. We have marked this device as 17518bc61209SDavid Schultz * SW_CLOSING, so the activity should finish soon. 175292da00bbSMatthew Dillon */ 17538bc61209SDavid Schultz retries++; 17548bc61209SDavid Schultz if (retries > 100) { 17558bc61209SDavid Schultz panic("swapoff: failed to locate %d swap blocks", 17568bc61209SDavid Schultz sp->sw_used); 17578bc61209SDavid Schultz } 17584d70511aSJohn Baldwin pause("swpoff", hz / 20); 175992da00bbSMatthew Dillon goto full_rescan; 176092da00bbSMatthew Dillon } 1761b1fd102eSMark Johnston EVENTHANDLER_INVOKE(swapoff, sp); 176292da00bbSMatthew Dillon } 176392da00bbSMatthew Dillon 17641c7c3c6aSMatthew Dillon /************************************************************************ 17651c7c3c6aSMatthew Dillon * SWAP META DATA * 17661c7c3c6aSMatthew Dillon ************************************************************************ 17671c7c3c6aSMatthew Dillon * 17681c7c3c6aSMatthew Dillon * These routines manipulate the swap metadata stored in the 1769cec9f109SDavid E. O'Brien * OBJT_SWAP object. 17701c7c3c6aSMatthew Dillon * 17714dcc5c2dSMatthew Dillon * Swap metadata is implemented with a global hash and not directly 17724dcc5c2dSMatthew Dillon * linked into the object. Instead the object simply contains 17734dcc5c2dSMatthew Dillon * appropriate tracking counters. 17741c7c3c6aSMatthew Dillon */ 17751c7c3c6aSMatthew Dillon 17761c7c3c6aSMatthew Dillon /* 17771c7c3c6aSMatthew Dillon * SWP_PAGER_META_BUILD() - add swap block to swap meta data for object 17781c7c3c6aSMatthew Dillon * 17791c7c3c6aSMatthew Dillon * We first convert the object to a swap object if it is a default 17801c7c3c6aSMatthew Dillon * object. 17811c7c3c6aSMatthew Dillon * 17821c7c3c6aSMatthew Dillon * The specified swapblk is added to the object's swap metadata. If 17831c7c3c6aSMatthew Dillon * the swapblk is not valid, it is freed instead. Any previously 17841c7c3c6aSMatthew Dillon * assigned swapblk is freed. 17851c7c3c6aSMatthew Dillon */ 17861c7c3c6aSMatthew Dillon static void 17872f249180SPoul-Henning Kamp swp_pager_meta_build(vm_object_t object, vm_pindex_t pindex, daddr_t swapblk) 17882f249180SPoul-Henning Kamp { 17893ff863f1SDag-Erling Smørgrav static volatile int exhausted; 17901c7c3c6aSMatthew Dillon struct swblock *swap; 17911c7c3c6aSMatthew Dillon struct swblock **pswap; 179223f09d50SIan Dowse int idx; 17931c7c3c6aSMatthew Dillon 179489f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(object); 17951c7c3c6aSMatthew Dillon /* 17961c7c3c6aSMatthew Dillon * Convert default object to swap object if necessary 17971c7c3c6aSMatthew Dillon */ 17981c7c3c6aSMatthew Dillon if (object->type != OBJT_SWAP) { 17991c7c3c6aSMatthew Dillon object->type = OBJT_SWAP; 18001c7c3c6aSMatthew Dillon object->un_pager.swp.swp_bcount = 0; 1801eb4d6a1bSKonstantin Belousov KASSERT(object->handle == NULL, ("default pager with handle")); 1802bd228075SAlan Cox } 18031c7c3c6aSMatthew Dillon 18041c7c3c6aSMatthew Dillon /* 18051c7c3c6aSMatthew Dillon * Locate hash entry. If not found create, but if we aren't adding 18064dcc5c2dSMatthew Dillon * anything just return. If we run out of space in the map we wait 18074dcc5c2dSMatthew Dillon * and, since the hash table may have changed, retry. 18081c7c3c6aSMatthew Dillon */ 18094dcc5c2dSMatthew Dillon retry: 18107827d9b0SAlan Cox mtx_lock(&swhash_mtx); 181123f09d50SIan Dowse pswap = swp_pager_hash(object, pindex); 18121c7c3c6aSMatthew Dillon 18131c7c3c6aSMatthew Dillon if ((swap = *pswap) == NULL) { 18141c7c3c6aSMatthew Dillon int i; 18151c7c3c6aSMatthew Dillon 18161c7c3c6aSMatthew Dillon if (swapblk == SWAPBLK_NONE) 18177827d9b0SAlan Cox goto done; 18181c7c3c6aSMatthew Dillon 18195a3c920fSKonstantin Belousov swap = *pswap = uma_zalloc(swap_zone, M_NOWAIT | 18205a3c920fSKonstantin Belousov (curproc == pageproc ? M_USE_RESERVE : 0)); 18214dcc5c2dSMatthew Dillon if (swap == NULL) { 18227827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 182389f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 18242025d69bSKonstantin Belousov if (uma_zone_exhausted(swap_zone)) { 1825dc1b35b5SDag-Erling Smørgrav if (atomic_cmpset_int(&exhausted, 0, 1)) 18263ff863f1SDag-Erling Smørgrav printf("swap zone exhausted, " 18273ff863f1SDag-Erling Smørgrav "increase kern.maxswzone\n"); 18282025d69bSKonstantin Belousov vm_pageout_oom(VM_OOM_SWAPZ); 18292025d69bSKonstantin Belousov pause("swzonex", 10); 18302025d69bSKonstantin Belousov } else 18314dcc5c2dSMatthew Dillon VM_WAIT; 183289f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 18334dcc5c2dSMatthew Dillon goto retry; 18344dcc5c2dSMatthew Dillon } 1835670d17b5SJeff Roberson 1836dc1b35b5SDag-Erling Smørgrav if (atomic_cmpset_int(&exhausted, 1, 0)) 18373ff863f1SDag-Erling Smørgrav printf("swap zone ok\n"); 18383ff863f1SDag-Erling Smørgrav 18391c7c3c6aSMatthew Dillon swap->swb_hnext = NULL; 18401c7c3c6aSMatthew Dillon swap->swb_object = object; 184123f09d50SIan Dowse swap->swb_index = pindex & ~(vm_pindex_t)SWAP_META_MASK; 18421c7c3c6aSMatthew Dillon swap->swb_count = 0; 18431c7c3c6aSMatthew Dillon 18441c7c3c6aSMatthew Dillon ++object->un_pager.swp.swp_bcount; 18451c7c3c6aSMatthew Dillon 18461c7c3c6aSMatthew Dillon for (i = 0; i < SWAP_META_PAGES; ++i) 18471c7c3c6aSMatthew Dillon swap->swb_pages[i] = SWAPBLK_NONE; 18481c7c3c6aSMatthew Dillon } 18491c7c3c6aSMatthew Dillon 18501c7c3c6aSMatthew Dillon /* 18511c7c3c6aSMatthew Dillon * Delete prior contents of metadata 18521c7c3c6aSMatthew Dillon */ 185323f09d50SIan Dowse idx = pindex & SWAP_META_MASK; 18541c7c3c6aSMatthew Dillon 185523f09d50SIan Dowse if (swap->swb_pages[idx] != SWAPBLK_NONE) { 185623f09d50SIan Dowse swp_pager_freeswapspace(swap->swb_pages[idx], 1); 18571c7c3c6aSMatthew Dillon --swap->swb_count; 18581c7c3c6aSMatthew Dillon } 18591c7c3c6aSMatthew Dillon 18601c7c3c6aSMatthew Dillon /* 18611c7c3c6aSMatthew Dillon * Enter block into metadata 18621c7c3c6aSMatthew Dillon */ 186323f09d50SIan Dowse swap->swb_pages[idx] = swapblk; 18644dcc5c2dSMatthew Dillon if (swapblk != SWAPBLK_NONE) 18651c7c3c6aSMatthew Dillon ++swap->swb_count; 18667827d9b0SAlan Cox done: 18677827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 18681c7c3c6aSMatthew Dillon } 18691c7c3c6aSMatthew Dillon 18701c7c3c6aSMatthew Dillon /* 18711c7c3c6aSMatthew Dillon * SWP_PAGER_META_FREE() - free a range of blocks in the object's swap metadata 18721c7c3c6aSMatthew Dillon * 18731c7c3c6aSMatthew Dillon * The requested range of blocks is freed, with any associated swap 18741c7c3c6aSMatthew Dillon * returned to the swap bitmap. 18751c7c3c6aSMatthew Dillon * 18761c7c3c6aSMatthew Dillon * This routine will free swap metadata structures as they are cleaned 18771c7c3c6aSMatthew Dillon * out. This routine does *NOT* operate on swap metadata associated 18781c7c3c6aSMatthew Dillon * with resident pages. 18791c7c3c6aSMatthew Dillon */ 18801c7c3c6aSMatthew Dillon static void 18812e56b64fSKonstantin Belousov swp_pager_meta_free(vm_object_t object, vm_pindex_t index, vm_pindex_t count) 18821c7c3c6aSMatthew Dillon { 18832e56b64fSKonstantin Belousov struct swblock **pswap, *swap; 18842e56b64fSKonstantin Belousov vm_pindex_t c; 18852e56b64fSKonstantin Belousov daddr_t v; 18862e56b64fSKonstantin Belousov int n, sidx; 18872928cef7SAlan Cox 1888c25673ffSAttilio Rao VM_OBJECT_ASSERT_LOCKED(object); 18892e56b64fSKonstantin Belousov if (object->type != OBJT_SWAP || count == 0) 18901c7c3c6aSMatthew Dillon return; 18911c7c3c6aSMatthew Dillon 18927827d9b0SAlan Cox mtx_lock(&swhash_mtx); 18932e56b64fSKonstantin Belousov for (c = 0; c < count;) { 18941c7c3c6aSMatthew Dillon pswap = swp_pager_hash(object, index); 18952e56b64fSKonstantin Belousov sidx = index & SWAP_META_MASK; 18962e56b64fSKonstantin Belousov n = SWAP_META_PAGES - sidx; 18972e56b64fSKonstantin Belousov index += n; 18982e56b64fSKonstantin Belousov if ((swap = *pswap) == NULL) { 18992e56b64fSKonstantin Belousov c += n; 19002e56b64fSKonstantin Belousov continue; 19012e56b64fSKonstantin Belousov } 19022e56b64fSKonstantin Belousov for (; c < count && sidx < SWAP_META_PAGES; ++c, ++sidx) { 19032e56b64fSKonstantin Belousov if ((v = swap->swb_pages[sidx]) == SWAPBLK_NONE) 19042e56b64fSKonstantin Belousov continue; 19051c7c3c6aSMatthew Dillon swp_pager_freeswapspace(v, 1); 19062e56b64fSKonstantin Belousov swap->swb_pages[sidx] = SWAPBLK_NONE; 19071c7c3c6aSMatthew Dillon if (--swap->swb_count == 0) { 19081c7c3c6aSMatthew Dillon *pswap = swap->swb_hnext; 1909670d17b5SJeff Roberson uma_zfree(swap_zone, swap); 19101c7c3c6aSMatthew Dillon --object->un_pager.swp.swp_bcount; 19112e56b64fSKonstantin Belousov c += SWAP_META_PAGES - sidx; 19122e56b64fSKonstantin Belousov break; 19131c7c3c6aSMatthew Dillon } 19141c7c3c6aSMatthew Dillon } 19151c7c3c6aSMatthew Dillon } 19167827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 19171c7c3c6aSMatthew Dillon } 19181c7c3c6aSMatthew Dillon 19191c7c3c6aSMatthew Dillon /* 19201c7c3c6aSMatthew Dillon * SWP_PAGER_META_FREE_ALL() - destroy all swap metadata associated with object 19211c7c3c6aSMatthew Dillon * 19221c7c3c6aSMatthew Dillon * This routine locates and destroys all swap metadata associated with 19231c7c3c6aSMatthew Dillon * an object. 19241c7c3c6aSMatthew Dillon */ 19251c7c3c6aSMatthew Dillon static void 19261c7c3c6aSMatthew Dillon swp_pager_meta_free_all(vm_object_t object) 19271c7c3c6aSMatthew Dillon { 192871057cd2SKonstantin Belousov struct swblock **pswap, *swap; 192971057cd2SKonstantin Belousov vm_pindex_t index; 193071057cd2SKonstantin Belousov daddr_t v; 193171057cd2SKonstantin Belousov int i; 19321c7c3c6aSMatthew Dillon 193389f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(object); 19341c7c3c6aSMatthew Dillon if (object->type != OBJT_SWAP) 19351c7c3c6aSMatthew Dillon return; 19361c7c3c6aSMatthew Dillon 193771057cd2SKonstantin Belousov index = 0; 193871057cd2SKonstantin Belousov while (object->un_pager.swp.swp_bcount != 0) { 19397827d9b0SAlan Cox mtx_lock(&swhash_mtx); 19401c7c3c6aSMatthew Dillon pswap = swp_pager_hash(object, index); 19411c7c3c6aSMatthew Dillon if ((swap = *pswap) != NULL) { 19421c7c3c6aSMatthew Dillon for (i = 0; i < SWAP_META_PAGES; ++i) { 194371057cd2SKonstantin Belousov v = swap->swb_pages[i]; 19441c7c3c6aSMatthew Dillon if (v != SWAPBLK_NONE) { 19451c7c3c6aSMatthew Dillon --swap->swb_count; 19464dcc5c2dSMatthew Dillon swp_pager_freeswapspace(v, 1); 19471c7c3c6aSMatthew Dillon } 19481c7c3c6aSMatthew Dillon } 19491c7c3c6aSMatthew Dillon if (swap->swb_count != 0) 195071057cd2SKonstantin Belousov panic( 195171057cd2SKonstantin Belousov "swap_pager_meta_free_all: swb_count != 0"); 19521c7c3c6aSMatthew Dillon *pswap = swap->swb_hnext; 1953670d17b5SJeff Roberson uma_zfree(swap_zone, swap); 19541c7c3c6aSMatthew Dillon --object->un_pager.swp.swp_bcount; 19551c7c3c6aSMatthew Dillon } 19567827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 19571c7c3c6aSMatthew Dillon index += SWAP_META_PAGES; 19581c7c3c6aSMatthew Dillon } 19591c7c3c6aSMatthew Dillon } 19601c7c3c6aSMatthew Dillon 19611c7c3c6aSMatthew Dillon /* 19621c7c3c6aSMatthew Dillon * SWP_PAGER_METACTL() - misc control of swap and vm_page_t meta data. 19631c7c3c6aSMatthew Dillon * 19641c7c3c6aSMatthew Dillon * This routine is capable of looking up, popping, or freeing 19651c7c3c6aSMatthew Dillon * swapblk assignments in the swap meta data or in the vm_page_t. 19661c7c3c6aSMatthew Dillon * The routine typically returns the swapblk being looked-up, or popped, 19671c7c3c6aSMatthew Dillon * or SWAPBLK_NONE if the block was freed, or SWAPBLK_NONE if the block 19681c7c3c6aSMatthew Dillon * was invalid. This routine will automatically free any invalid 19691c7c3c6aSMatthew Dillon * meta-data swapblks. 19701c7c3c6aSMatthew Dillon * 19711c7c3c6aSMatthew Dillon * It is not possible to store invalid swapblks in the swap meta data 19721c7c3c6aSMatthew Dillon * (other then a literal 'SWAPBLK_NONE'), so we don't bother checking. 19731c7c3c6aSMatthew Dillon * 19741c7c3c6aSMatthew Dillon * When acting on a busy resident page and paging is in progress, we 19751c7c3c6aSMatthew Dillon * have to wait until paging is complete but otherwise can act on the 19761c7c3c6aSMatthew Dillon * busy page. 19771c7c3c6aSMatthew Dillon * 19784dcc5c2dSMatthew Dillon * SWM_FREE remove and free swap block from metadata 19791c7c3c6aSMatthew Dillon * SWM_POP remove from meta data but do not free.. pop it out 19801c7c3c6aSMatthew Dillon */ 19811c7c3c6aSMatthew Dillon static daddr_t 19822f249180SPoul-Henning Kamp swp_pager_meta_ctl(vm_object_t object, vm_pindex_t pindex, int flags) 19832f249180SPoul-Henning Kamp { 19844dcc5c2dSMatthew Dillon struct swblock **pswap; 19854dcc5c2dSMatthew Dillon struct swblock *swap; 19864dcc5c2dSMatthew Dillon daddr_t r1; 198723f09d50SIan Dowse int idx; 19884dcc5c2dSMatthew Dillon 1989c25673ffSAttilio Rao VM_OBJECT_ASSERT_LOCKED(object); 19901c7c3c6aSMatthew Dillon /* 19911c7c3c6aSMatthew Dillon * The meta data only exists of the object is OBJT_SWAP 19921c7c3c6aSMatthew Dillon * and even then might not be allocated yet. 19931c7c3c6aSMatthew Dillon */ 19944dcc5c2dSMatthew Dillon if (object->type != OBJT_SWAP) 19951c7c3c6aSMatthew Dillon return (SWAPBLK_NONE); 19961c7c3c6aSMatthew Dillon 19974dcc5c2dSMatthew Dillon r1 = SWAPBLK_NONE; 19987827d9b0SAlan Cox mtx_lock(&swhash_mtx); 199923f09d50SIan Dowse pswap = swp_pager_hash(object, pindex); 20001c7c3c6aSMatthew Dillon 20011c7c3c6aSMatthew Dillon if ((swap = *pswap) != NULL) { 200223f09d50SIan Dowse idx = pindex & SWAP_META_MASK; 200323f09d50SIan Dowse r1 = swap->swb_pages[idx]; 20041c7c3c6aSMatthew Dillon 20051c7c3c6aSMatthew Dillon if (r1 != SWAPBLK_NONE) { 20061c7c3c6aSMatthew Dillon if (flags & SWM_FREE) { 20074dcc5c2dSMatthew Dillon swp_pager_freeswapspace(r1, 1); 20081c7c3c6aSMatthew Dillon r1 = SWAPBLK_NONE; 20091c7c3c6aSMatthew Dillon } 20101c7c3c6aSMatthew Dillon if (flags & (SWM_FREE|SWM_POP)) { 201123f09d50SIan Dowse swap->swb_pages[idx] = SWAPBLK_NONE; 20121c7c3c6aSMatthew Dillon if (--swap->swb_count == 0) { 20131c7c3c6aSMatthew Dillon *pswap = swap->swb_hnext; 2014670d17b5SJeff Roberson uma_zfree(swap_zone, swap); 20151c7c3c6aSMatthew Dillon --object->un_pager.swp.swp_bcount; 20161c7c3c6aSMatthew Dillon } 20171c7c3c6aSMatthew Dillon } 20181c7c3c6aSMatthew Dillon } 20191c7c3c6aSMatthew Dillon } 20207827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 20211c7c3c6aSMatthew Dillon return (r1); 20221c7c3c6aSMatthew Dillon } 20231c7c3c6aSMatthew Dillon 2024e9c0cc15SPoul-Henning Kamp /* 202577d6fd97SKonstantin Belousov * Returns the least page index which is greater than or equal to the 202677d6fd97SKonstantin Belousov * parameter pindex and for which there is a swap block allocated. 202777d6fd97SKonstantin Belousov * Returns object's size if the object's type is not swap or if there 202877d6fd97SKonstantin Belousov * are no allocated swap blocks for the object after the requested 202977d6fd97SKonstantin Belousov * pindex. 203077d6fd97SKonstantin Belousov */ 203177d6fd97SKonstantin Belousov vm_pindex_t 203277d6fd97SKonstantin Belousov swap_pager_find_least(vm_object_t object, vm_pindex_t pindex) 203377d6fd97SKonstantin Belousov { 203477d6fd97SKonstantin Belousov struct swblock **pswap, *swap; 203577d6fd97SKonstantin Belousov vm_pindex_t i, j, lim; 203677d6fd97SKonstantin Belousov int idx; 203777d6fd97SKonstantin Belousov 203877d6fd97SKonstantin Belousov VM_OBJECT_ASSERT_LOCKED(object); 203977d6fd97SKonstantin Belousov if (object->type != OBJT_SWAP || object->un_pager.swp.swp_bcount == 0) 204077d6fd97SKonstantin Belousov return (object->size); 204177d6fd97SKonstantin Belousov 204277d6fd97SKonstantin Belousov mtx_lock(&swhash_mtx); 204377d6fd97SKonstantin Belousov for (j = pindex; j < object->size; j = lim) { 204477d6fd97SKonstantin Belousov pswap = swp_pager_hash(object, j); 204577d6fd97SKonstantin Belousov lim = rounddown2(j + SWAP_META_PAGES, SWAP_META_PAGES); 204677d6fd97SKonstantin Belousov if (lim > object->size) 204777d6fd97SKonstantin Belousov lim = object->size; 204877d6fd97SKonstantin Belousov if ((swap = *pswap) != NULL) { 204977d6fd97SKonstantin Belousov for (idx = j & SWAP_META_MASK, i = j; i < lim; 205077d6fd97SKonstantin Belousov i++, idx++) { 205177d6fd97SKonstantin Belousov if (swap->swb_pages[idx] != SWAPBLK_NONE) 205277d6fd97SKonstantin Belousov goto found; 205377d6fd97SKonstantin Belousov } 205477d6fd97SKonstantin Belousov } 205577d6fd97SKonstantin Belousov } 205677d6fd97SKonstantin Belousov i = object->size; 205777d6fd97SKonstantin Belousov found: 205877d6fd97SKonstantin Belousov mtx_unlock(&swhash_mtx); 205977d6fd97SKonstantin Belousov return (i); 206077d6fd97SKonstantin Belousov } 206177d6fd97SKonstantin Belousov 206277d6fd97SKonstantin Belousov /* 2063e9c0cc15SPoul-Henning Kamp * System call swapon(name) enables swapping on device name, 2064e9c0cc15SPoul-Henning Kamp * which must be in the swdevsw. Return EBUSY 2065e9c0cc15SPoul-Henning Kamp * if already swapping on this device. 2066e9c0cc15SPoul-Henning Kamp */ 2067e9c0cc15SPoul-Henning Kamp #ifndef _SYS_SYSPROTO_H_ 2068e9c0cc15SPoul-Henning Kamp struct swapon_args { 2069e9c0cc15SPoul-Henning Kamp char *name; 2070e9c0cc15SPoul-Henning Kamp }; 2071e9c0cc15SPoul-Henning Kamp #endif 2072e9c0cc15SPoul-Henning Kamp 2073e9c0cc15SPoul-Henning Kamp /* 2074e9c0cc15SPoul-Henning Kamp * MPSAFE 2075e9c0cc15SPoul-Henning Kamp */ 2076e9c0cc15SPoul-Henning Kamp /* ARGSUSED */ 2077e9c0cc15SPoul-Henning Kamp int 20788451d0ddSKip Macy sys_swapon(struct thread *td, struct swapon_args *uap) 2079e9c0cc15SPoul-Henning Kamp { 2080e9c0cc15SPoul-Henning Kamp struct vattr attr; 2081e9c0cc15SPoul-Henning Kamp struct vnode *vp; 2082e9c0cc15SPoul-Henning Kamp struct nameidata nd; 2083e9c0cc15SPoul-Henning Kamp int error; 2084e9c0cc15SPoul-Henning Kamp 2085acd3428bSRobert Watson error = priv_check(td, PRIV_SWAPON); 2086e9c0cc15SPoul-Henning Kamp if (error) 2087acd3428bSRobert Watson return (error); 2088e9c0cc15SPoul-Henning Kamp 208904533e1eSKonstantin Belousov sx_xlock(&swdev_syscall_lock); 2090e9c0cc15SPoul-Henning Kamp 2091e9c0cc15SPoul-Henning Kamp /* 2092e9c0cc15SPoul-Henning Kamp * Swap metadata may not fit in the KVM if we have physical 2093e9c0cc15SPoul-Henning Kamp * memory of >1GB. 2094e9c0cc15SPoul-Henning Kamp */ 2095e9c0cc15SPoul-Henning Kamp if (swap_zone == NULL) { 2096e9c0cc15SPoul-Henning Kamp error = ENOMEM; 2097e9c0cc15SPoul-Henning Kamp goto done; 2098e9c0cc15SPoul-Henning Kamp } 2099e9c0cc15SPoul-Henning Kamp 2100d9135e72SRobert Watson NDINIT(&nd, LOOKUP, ISOPEN | FOLLOW | AUDITVNODE1, UIO_USERSPACE, 2101d9135e72SRobert Watson uap->name, td); 2102e9c0cc15SPoul-Henning Kamp error = namei(&nd); 2103e9c0cc15SPoul-Henning Kamp if (error) 2104e9c0cc15SPoul-Henning Kamp goto done; 2105e9c0cc15SPoul-Henning Kamp 2106e9c0cc15SPoul-Henning Kamp NDFREE(&nd, NDF_ONLY_PNBUF); 2107e9c0cc15SPoul-Henning Kamp vp = nd.ni_vp; 2108e9c0cc15SPoul-Henning Kamp 210920da9c2eSPoul-Henning Kamp if (vn_isdisk(vp, &error)) { 211088ad2d7bSKonstantin Belousov error = swapongeom(vp); 211120da9c2eSPoul-Henning Kamp } else if (vp->v_type == VREG && 2112e9c0cc15SPoul-Henning Kamp (vp->v_mount->mnt_vfc->vfc_flags & VFCF_NETWORK) != 0 && 21130359a12eSAttilio Rao (error = VOP_GETATTR(vp, &attr, td->td_ucred)) == 0) { 2114e9c0cc15SPoul-Henning Kamp /* 2115e9c0cc15SPoul-Henning Kamp * Allow direct swapping to NFS regular files in the same 2116e9c0cc15SPoul-Henning Kamp * way that nfs_mountroot() sets up diskless swapping. 2117e9c0cc15SPoul-Henning Kamp */ 211859efee01SPoul-Henning Kamp error = swaponvp(td, vp, attr.va_size / DEV_BSIZE); 2119e9c0cc15SPoul-Henning Kamp } 2120e9c0cc15SPoul-Henning Kamp 2121e9c0cc15SPoul-Henning Kamp if (error) 2122e9c0cc15SPoul-Henning Kamp vrele(vp); 2123e9c0cc15SPoul-Henning Kamp done: 212404533e1eSKonstantin Belousov sx_xunlock(&swdev_syscall_lock); 2125e9c0cc15SPoul-Henning Kamp return (error); 2126e9c0cc15SPoul-Henning Kamp } 2127e9c0cc15SPoul-Henning Kamp 21283ff863f1SDag-Erling Smørgrav /* 21293ff863f1SDag-Erling Smørgrav * Check that the total amount of swap currently configured does not 21303ff863f1SDag-Erling Smørgrav * exceed half the theoretical maximum. If it does, print a warning 21313ff863f1SDag-Erling Smørgrav * message and return -1; otherwise, return 0. 21323ff863f1SDag-Erling Smørgrav */ 21333ff863f1SDag-Erling Smørgrav static int 21343ff863f1SDag-Erling Smørgrav swapon_check_swzone(unsigned long npages) 21353ff863f1SDag-Erling Smørgrav { 21363ff863f1SDag-Erling Smørgrav unsigned long maxpages; 21373ff863f1SDag-Erling Smørgrav 21383ff863f1SDag-Erling Smørgrav /* absolute maximum we can handle assuming 100% efficiency */ 21393ff863f1SDag-Erling Smørgrav maxpages = uma_zone_get_max(swap_zone) * SWAP_META_PAGES; 21403ff863f1SDag-Erling Smørgrav 21413ff863f1SDag-Erling Smørgrav /* recommend using no more than half that amount */ 21423ff863f1SDag-Erling Smørgrav if (npages > maxpages / 2) { 21433ff863f1SDag-Erling Smørgrav printf("warning: total configured swap (%lu pages) " 21443ff863f1SDag-Erling Smørgrav "exceeds maximum recommended amount (%lu pages).\n", 21459462305cSSergey Kandaurov npages, maxpages / 2); 21463ff863f1SDag-Erling Smørgrav printf("warning: increase kern.maxswzone " 21473ff863f1SDag-Erling Smørgrav "or reduce amount of swap.\n"); 21483ff863f1SDag-Erling Smørgrav return (-1); 21493ff863f1SDag-Erling Smørgrav } 21503ff863f1SDag-Erling Smørgrav return (0); 21513ff863f1SDag-Erling Smørgrav } 21523ff863f1SDag-Erling Smørgrav 215359efee01SPoul-Henning Kamp static void 21542cc718a1SKonstantin Belousov swaponsomething(struct vnode *vp, void *id, u_long nblks, 21552cc718a1SKonstantin Belousov sw_strategy_t *strategy, sw_close_t *close, dev_t dev, int flags) 2156e9c0cc15SPoul-Henning Kamp { 21572d9974c1SAlan Cox struct swdevt *sp, *tsp; 2158e9c0cc15SPoul-Henning Kamp swblk_t dvbase; 21598f60c087SPoul-Henning Kamp u_long mblocks; 2160e9c0cc15SPoul-Henning Kamp 2161e9c0cc15SPoul-Henning Kamp /* 2162e9c0cc15SPoul-Henning Kamp * nblks is in DEV_BSIZE'd chunks, convert to PAGE_SIZE'd chunks. 2163e9c0cc15SPoul-Henning Kamp * First chop nblks off to page-align it, then convert. 2164e9c0cc15SPoul-Henning Kamp * 2165e9c0cc15SPoul-Henning Kamp * sw->sw_nblks is in page-sized chunks now too. 2166e9c0cc15SPoul-Henning Kamp */ 2167e9c0cc15SPoul-Henning Kamp nblks &= ~(ctodb(1) - 1); 2168e9c0cc15SPoul-Henning Kamp nblks = dbtoc(nblks); 2169e9c0cc15SPoul-Henning Kamp 21706e903bd0SKonstantin Belousov /* 21716e903bd0SKonstantin Belousov * If we go beyond this, we get overflows in the radix 21726e903bd0SKonstantin Belousov * tree bitmap code. 21736e903bd0SKonstantin Belousov */ 21746e903bd0SKonstantin Belousov mblocks = 0x40000000 / BLIST_META_RADIX; 21756e903bd0SKonstantin Belousov if (nblks > mblocks) { 21766e903bd0SKonstantin Belousov printf( 21776e903bd0SKonstantin Belousov "WARNING: reducing swap size to maximum of %luMB per unit\n", 21786e903bd0SKonstantin Belousov mblocks / 1024 / 1024 * PAGE_SIZE); 21796e903bd0SKonstantin Belousov nblks = mblocks; 21806e903bd0SKonstantin Belousov } 21816e903bd0SKonstantin Belousov 21828f60c087SPoul-Henning Kamp sp = malloc(sizeof *sp, M_VMPGDATA, M_WAITOK | M_ZERO); 2183dee34ca4SPoul-Henning Kamp sp->sw_vp = vp; 2184dee34ca4SPoul-Henning Kamp sp->sw_id = id; 2185f3732fd1SPoul-Henning Kamp sp->sw_dev = dev; 21868d677ef9SPoul-Henning Kamp sp->sw_flags = 0; 2187e9c0cc15SPoul-Henning Kamp sp->sw_nblks = nblks; 2188e9c0cc15SPoul-Henning Kamp sp->sw_used = 0; 218959efee01SPoul-Henning Kamp sp->sw_strategy = strategy; 2190dee34ca4SPoul-Henning Kamp sp->sw_close = close; 21912cc718a1SKonstantin Belousov sp->sw_flags = flags; 2192e9c0cc15SPoul-Henning Kamp 2193c8c7ad92SKip Macy sp->sw_blist = blist_create(nblks, M_WAITOK); 2194e9c0cc15SPoul-Henning Kamp /* 2195ef3c5abdSPoul-Henning Kamp * Do not free the first two block in order to avoid overwriting 21968f60c087SPoul-Henning Kamp * any bsd label at the front of the partition 2197e9c0cc15SPoul-Henning Kamp */ 2198ef3c5abdSPoul-Henning Kamp blist_free(sp->sw_blist, 2, nblks - 2); 2199e9c0cc15SPoul-Henning Kamp 22002d9974c1SAlan Cox dvbase = 0; 220120da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 22022d9974c1SAlan Cox TAILQ_FOREACH(tsp, &swtailq, sw_list) { 22032d9974c1SAlan Cox if (tsp->sw_end >= dvbase) { 22042d9974c1SAlan Cox /* 22052d9974c1SAlan Cox * We put one uncovered page between the devices 22062d9974c1SAlan Cox * in order to definitively prevent any cross-device 22072d9974c1SAlan Cox * I/O requests 22082d9974c1SAlan Cox */ 22092d9974c1SAlan Cox dvbase = tsp->sw_end + 1; 22102d9974c1SAlan Cox } 22112d9974c1SAlan Cox } 22122d9974c1SAlan Cox sp->sw_first = dvbase; 22132d9974c1SAlan Cox sp->sw_end = dvbase + nblks; 22148f60c087SPoul-Henning Kamp TAILQ_INSERT_TAIL(&swtailq, sp, sw_list); 22158f60c087SPoul-Henning Kamp nswapdev++; 22168f60c087SPoul-Henning Kamp swap_pager_avail += nblks; 22173364c323SKonstantin Belousov swap_total += (vm_ooffset_t)nblks * PAGE_SIZE; 22183ff863f1SDag-Erling Smørgrav swapon_check_swzone(swap_total / PAGE_SIZE); 2219d05bc129SAlan Cox swp_sizecheck(); 2220d05bc129SAlan Cox mtx_unlock(&sw_dev_mtx); 2221b1fd102eSMark Johnston EVENTHANDLER_INVOKE(swapon, sp); 222259efee01SPoul-Henning Kamp } 2223e9c0cc15SPoul-Henning Kamp 2224e9c0cc15SPoul-Henning Kamp /* 2225e9c0cc15SPoul-Henning Kamp * SYSCALL: swapoff(devname) 2226e9c0cc15SPoul-Henning Kamp * 2227e9c0cc15SPoul-Henning Kamp * Disable swapping on the given device. 2228dee34ca4SPoul-Henning Kamp * 2229dee34ca4SPoul-Henning Kamp * XXX: Badly designed system call: it should use a device index 2230dee34ca4SPoul-Henning Kamp * rather than filename as specification. We keep sw_vp around 2231dee34ca4SPoul-Henning Kamp * only to make this work. 2232e9c0cc15SPoul-Henning Kamp */ 2233e9c0cc15SPoul-Henning Kamp #ifndef _SYS_SYSPROTO_H_ 2234e9c0cc15SPoul-Henning Kamp struct swapoff_args { 2235e9c0cc15SPoul-Henning Kamp char *name; 2236e9c0cc15SPoul-Henning Kamp }; 2237e9c0cc15SPoul-Henning Kamp #endif 2238e9c0cc15SPoul-Henning Kamp 2239e9c0cc15SPoul-Henning Kamp /* 2240e9c0cc15SPoul-Henning Kamp * MPSAFE 2241e9c0cc15SPoul-Henning Kamp */ 2242e9c0cc15SPoul-Henning Kamp /* ARGSUSED */ 2243e9c0cc15SPoul-Henning Kamp int 22448451d0ddSKip Macy sys_swapoff(struct thread *td, struct swapoff_args *uap) 2245e9c0cc15SPoul-Henning Kamp { 2246e9c0cc15SPoul-Henning Kamp struct vnode *vp; 2247e9c0cc15SPoul-Henning Kamp struct nameidata nd; 2248e9c0cc15SPoul-Henning Kamp struct swdevt *sp; 22498f60c087SPoul-Henning Kamp int error; 2250e9c0cc15SPoul-Henning Kamp 2251acd3428bSRobert Watson error = priv_check(td, PRIV_SWAPOFF); 2252e9c0cc15SPoul-Henning Kamp if (error) 22530909f38aSPawel Jakub Dawidek return (error); 2254e9c0cc15SPoul-Henning Kamp 225504533e1eSKonstantin Belousov sx_xlock(&swdev_syscall_lock); 2256e9c0cc15SPoul-Henning Kamp 2257d9135e72SRobert Watson NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNODE1, UIO_USERSPACE, uap->name, 2258d9135e72SRobert Watson td); 2259e9c0cc15SPoul-Henning Kamp error = namei(&nd); 2260e9c0cc15SPoul-Henning Kamp if (error) 2261e9c0cc15SPoul-Henning Kamp goto done; 2262e9c0cc15SPoul-Henning Kamp NDFREE(&nd, NDF_ONLY_PNBUF); 2263e9c0cc15SPoul-Henning Kamp vp = nd.ni_vp; 2264e9c0cc15SPoul-Henning Kamp 226520da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 22668f60c087SPoul-Henning Kamp TAILQ_FOREACH(sp, &swtailq, sw_list) { 2267dee34ca4SPoul-Henning Kamp if (sp->sw_vp == vp) 22680909f38aSPawel Jakub Dawidek break; 2269e9c0cc15SPoul-Henning Kamp } 227020da9c2eSPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 22710909f38aSPawel Jakub Dawidek if (sp == NULL) { 2272e9c0cc15SPoul-Henning Kamp error = EINVAL; 2273e9c0cc15SPoul-Henning Kamp goto done; 22740909f38aSPawel Jakub Dawidek } 227535918c55SChristian S.J. Peron error = swapoff_one(sp, td->td_ucred); 22760909f38aSPawel Jakub Dawidek done: 227704533e1eSKonstantin Belousov sx_xunlock(&swdev_syscall_lock); 22780909f38aSPawel Jakub Dawidek return (error); 22790909f38aSPawel Jakub Dawidek } 22800909f38aSPawel Jakub Dawidek 22810909f38aSPawel Jakub Dawidek static int 228235918c55SChristian S.J. Peron swapoff_one(struct swdevt *sp, struct ucred *cred) 22830909f38aSPawel Jakub Dawidek { 22840909f38aSPawel Jakub Dawidek u_long nblks, dvbase; 2285e9c0cc15SPoul-Henning Kamp #ifdef MAC 22860909f38aSPawel Jakub Dawidek int error; 2287e9c0cc15SPoul-Henning Kamp #endif 2288e9c0cc15SPoul-Henning Kamp 228904533e1eSKonstantin Belousov sx_assert(&swdev_syscall_lock, SA_XLOCKED); 22900909f38aSPawel Jakub Dawidek #ifdef MAC 2291cb05b60aSAttilio Rao (void) vn_lock(sp->sw_vp, LK_EXCLUSIVE | LK_RETRY); 229235918c55SChristian S.J. Peron error = mac_system_check_swapoff(cred, sp->sw_vp); 229322db15c0SAttilio Rao (void) VOP_UNLOCK(sp->sw_vp, 0); 22940909f38aSPawel Jakub Dawidek if (error != 0) 22950909f38aSPawel Jakub Dawidek return (error); 22960909f38aSPawel Jakub Dawidek #endif 2297e9c0cc15SPoul-Henning Kamp nblks = sp->sw_nblks; 2298e9c0cc15SPoul-Henning Kamp 2299e9c0cc15SPoul-Henning Kamp /* 2300e9c0cc15SPoul-Henning Kamp * We can turn off this swap device safely only if the 2301e9c0cc15SPoul-Henning Kamp * available virtual memory in the system will fit the amount 2302e9c0cc15SPoul-Henning Kamp * of data we will have to page back in, plus an epsilon so 2303e9c0cc15SPoul-Henning Kamp * the system doesn't become critically low on swap space. 2304e9c0cc15SPoul-Henning Kamp */ 2305bba39b9aSAlan Cox if (vm_cnt.v_free_count + swap_pager_avail < nblks + nswap_lowat) 23060909f38aSPawel Jakub Dawidek return (ENOMEM); 2307e9c0cc15SPoul-Henning Kamp 2308e9c0cc15SPoul-Henning Kamp /* 2309e9c0cc15SPoul-Henning Kamp * Prevent further allocations on this device. 2310e9c0cc15SPoul-Henning Kamp */ 23112928cef7SAlan Cox mtx_lock(&sw_dev_mtx); 2312e9c0cc15SPoul-Henning Kamp sp->sw_flags |= SW_CLOSING; 23138f60c087SPoul-Henning Kamp for (dvbase = 0; dvbase < sp->sw_end; dvbase += dmmax) { 23148f60c087SPoul-Henning Kamp swap_pager_avail -= blist_fill(sp->sw_blist, 23158f60c087SPoul-Henning Kamp dvbase, dmmax); 2316e9c0cc15SPoul-Henning Kamp } 23173364c323SKonstantin Belousov swap_total -= (vm_ooffset_t)nblks * PAGE_SIZE; 23182928cef7SAlan Cox mtx_unlock(&sw_dev_mtx); 2319e9c0cc15SPoul-Henning Kamp 2320e9c0cc15SPoul-Henning Kamp /* 2321e9c0cc15SPoul-Henning Kamp * Page in the contents of the device and close it. 2322e9c0cc15SPoul-Henning Kamp */ 2323b3fed13eSDavid Schultz swap_pager_swapoff(sp); 2324e9c0cc15SPoul-Henning Kamp 232535918c55SChristian S.J. Peron sp->sw_close(curthread, sp); 232620da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 23279e3e3fe5SWarner Losh sp->sw_id = NULL; 23288f60c087SPoul-Henning Kamp TAILQ_REMOVE(&swtailq, sp, sw_list); 23290676a140SAlan Cox nswapdev--; 23307dea2c2eSAlan Cox if (nswapdev == 0) { 23317dea2c2eSAlan Cox swap_pager_full = 2; 23327dea2c2eSAlan Cox swap_pager_almost_full = 1; 23337dea2c2eSAlan Cox } 23348f60c087SPoul-Henning Kamp if (swdevhd == sp) 23358f60c087SPoul-Henning Kamp swdevhd = NULL; 2336d05bc129SAlan Cox mtx_unlock(&sw_dev_mtx); 23378f60c087SPoul-Henning Kamp blist_destroy(sp->sw_blist); 23388f60c087SPoul-Henning Kamp free(sp, M_VMPGDATA); 23390909f38aSPawel Jakub Dawidek return (0); 23400909f38aSPawel Jakub Dawidek } 2341e9c0cc15SPoul-Henning Kamp 23420909f38aSPawel Jakub Dawidek void 23430909f38aSPawel Jakub Dawidek swapoff_all(void) 23440909f38aSPawel Jakub Dawidek { 23450909f38aSPawel Jakub Dawidek struct swdevt *sp, *spt; 23460909f38aSPawel Jakub Dawidek const char *devname; 23470909f38aSPawel Jakub Dawidek int error; 23480909f38aSPawel Jakub Dawidek 234904533e1eSKonstantin Belousov sx_xlock(&swdev_syscall_lock); 23500909f38aSPawel Jakub Dawidek 23510909f38aSPawel Jakub Dawidek mtx_lock(&sw_dev_mtx); 23520909f38aSPawel Jakub Dawidek TAILQ_FOREACH_SAFE(sp, &swtailq, sw_list, spt) { 23530909f38aSPawel Jakub Dawidek mtx_unlock(&sw_dev_mtx); 23540909f38aSPawel Jakub Dawidek if (vn_isdisk(sp->sw_vp, NULL)) 23557870adb6SEd Schouten devname = devtoname(sp->sw_vp->v_rdev); 23560909f38aSPawel Jakub Dawidek else 23570909f38aSPawel Jakub Dawidek devname = "[file]"; 235835918c55SChristian S.J. Peron error = swapoff_one(sp, thread0.td_ucred); 23590909f38aSPawel Jakub Dawidek if (error != 0) { 23600909f38aSPawel Jakub Dawidek printf("Cannot remove swap device %s (error=%d), " 23610909f38aSPawel Jakub Dawidek "skipping.\n", devname, error); 23620909f38aSPawel Jakub Dawidek } else if (bootverbose) { 23630909f38aSPawel Jakub Dawidek printf("Swap device %s removed.\n", devname); 23640909f38aSPawel Jakub Dawidek } 23650909f38aSPawel Jakub Dawidek mtx_lock(&sw_dev_mtx); 23660909f38aSPawel Jakub Dawidek } 23670909f38aSPawel Jakub Dawidek mtx_unlock(&sw_dev_mtx); 23680909f38aSPawel Jakub Dawidek 236904533e1eSKonstantin Belousov sx_xunlock(&swdev_syscall_lock); 2370e9c0cc15SPoul-Henning Kamp } 2371e9c0cc15SPoul-Henning Kamp 2372567104a1SPoul-Henning Kamp void 2373567104a1SPoul-Henning Kamp swap_pager_status(int *total, int *used) 2374567104a1SPoul-Henning Kamp { 2375567104a1SPoul-Henning Kamp struct swdevt *sp; 2376567104a1SPoul-Henning Kamp 2377567104a1SPoul-Henning Kamp *total = 0; 2378567104a1SPoul-Henning Kamp *used = 0; 237920da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 23808f60c087SPoul-Henning Kamp TAILQ_FOREACH(sp, &swtailq, sw_list) { 2381567104a1SPoul-Henning Kamp *total += sp->sw_nblks; 2382567104a1SPoul-Henning Kamp *used += sp->sw_used; 2383567104a1SPoul-Henning Kamp } 238420da9c2eSPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 2385567104a1SPoul-Henning Kamp } 2386567104a1SPoul-Henning Kamp 2387dda4f960SKonstantin Belousov int 2388dda4f960SKonstantin Belousov swap_dev_info(int name, struct xswdev *xs, char *devname, size_t len) 2389dda4f960SKonstantin Belousov { 2390dda4f960SKonstantin Belousov struct swdevt *sp; 23917870adb6SEd Schouten const char *tmp_devname; 2392dda4f960SKonstantin Belousov int error, n; 2393dda4f960SKonstantin Belousov 2394dda4f960SKonstantin Belousov n = 0; 2395dda4f960SKonstantin Belousov error = ENOENT; 2396dda4f960SKonstantin Belousov mtx_lock(&sw_dev_mtx); 2397dda4f960SKonstantin Belousov TAILQ_FOREACH(sp, &swtailq, sw_list) { 2398dda4f960SKonstantin Belousov if (n != name) { 2399dda4f960SKonstantin Belousov n++; 2400dda4f960SKonstantin Belousov continue; 2401dda4f960SKonstantin Belousov } 2402dda4f960SKonstantin Belousov xs->xsw_version = XSWDEV_VERSION; 2403dda4f960SKonstantin Belousov xs->xsw_dev = sp->sw_dev; 2404dda4f960SKonstantin Belousov xs->xsw_flags = sp->sw_flags; 2405dda4f960SKonstantin Belousov xs->xsw_nblks = sp->sw_nblks; 2406dda4f960SKonstantin Belousov xs->xsw_used = sp->sw_used; 2407dda4f960SKonstantin Belousov if (devname != NULL) { 2408dda4f960SKonstantin Belousov if (vn_isdisk(sp->sw_vp, NULL)) 24097870adb6SEd Schouten tmp_devname = devtoname(sp->sw_vp->v_rdev); 2410dda4f960SKonstantin Belousov else 2411dda4f960SKonstantin Belousov tmp_devname = "[file]"; 2412dda4f960SKonstantin Belousov strncpy(devname, tmp_devname, len); 2413dda4f960SKonstantin Belousov } 2414dda4f960SKonstantin Belousov error = 0; 2415dda4f960SKonstantin Belousov break; 2416dda4f960SKonstantin Belousov } 2417dda4f960SKonstantin Belousov mtx_unlock(&sw_dev_mtx); 2418dda4f960SKonstantin Belousov return (error); 2419dda4f960SKonstantin Belousov } 2420dda4f960SKonstantin Belousov 2421*69921123SKonstantin Belousov #if defined(COMPAT_FREEBSD11) 2422*69921123SKonstantin Belousov #define XSWDEV_VERSION_11 1 2423*69921123SKonstantin Belousov struct xswdev11 { 2424*69921123SKonstantin Belousov u_int xsw_version; 2425*69921123SKonstantin Belousov uint32_t xsw_dev; 2426*69921123SKonstantin Belousov int xsw_flags; 2427*69921123SKonstantin Belousov int xsw_nblks; 2428*69921123SKonstantin Belousov int xsw_used; 2429*69921123SKonstantin Belousov }; 2430*69921123SKonstantin Belousov #endif 2431*69921123SKonstantin Belousov 2432e9c0cc15SPoul-Henning Kamp static int 2433e9c0cc15SPoul-Henning Kamp sysctl_vm_swap_info(SYSCTL_HANDLER_ARGS) 2434e9c0cc15SPoul-Henning Kamp { 2435e9c0cc15SPoul-Henning Kamp struct xswdev xs; 2436*69921123SKonstantin Belousov #if defined(COMPAT_FREEBSD11) 2437*69921123SKonstantin Belousov struct xswdev11 xs11; 2438*69921123SKonstantin Belousov #endif 2439dda4f960SKonstantin Belousov int error; 2440e9c0cc15SPoul-Henning Kamp 2441e9c0cc15SPoul-Henning Kamp if (arg2 != 1) /* name length */ 2442e9c0cc15SPoul-Henning Kamp return (EINVAL); 2443dda4f960SKonstantin Belousov error = swap_dev_info(*(int *)arg1, &xs, NULL, 0); 2444dda4f960SKonstantin Belousov if (error != 0) 2445dda4f960SKonstantin Belousov return (error); 2446*69921123SKonstantin Belousov #if defined(COMPAT_FREEBSD11) 2447*69921123SKonstantin Belousov if (req->oldlen == sizeof(xs11)) { 2448*69921123SKonstantin Belousov xs11.xsw_version = XSWDEV_VERSION_11; 2449*69921123SKonstantin Belousov xs11.xsw_dev = xs.xsw_dev; /* truncation */ 2450*69921123SKonstantin Belousov xs11.xsw_flags = xs.xsw_flags; 2451*69921123SKonstantin Belousov xs11.xsw_nblks = xs.xsw_nblks; 2452*69921123SKonstantin Belousov xs11.xsw_used = xs.xsw_used; 2453*69921123SKonstantin Belousov error = SYSCTL_OUT(req, &xs11, sizeof(xs11)); 2454*69921123SKonstantin Belousov } else 2455*69921123SKonstantin Belousov #endif 2456e9c0cc15SPoul-Henning Kamp error = SYSCTL_OUT(req, &xs, sizeof(xs)); 2457e9c0cc15SPoul-Henning Kamp return (error); 2458e9c0cc15SPoul-Henning Kamp } 2459e9c0cc15SPoul-Henning Kamp 24608f60c087SPoul-Henning Kamp SYSCTL_INT(_vm, OID_AUTO, nswapdev, CTLFLAG_RD, &nswapdev, 0, 2461e9c0cc15SPoul-Henning Kamp "Number of swap devices"); 24624c36e917SKonstantin Belousov SYSCTL_NODE(_vm, OID_AUTO, swap_info, CTLFLAG_RD | CTLFLAG_MPSAFE, 24634c36e917SKonstantin Belousov sysctl_vm_swap_info, 2464e9c0cc15SPoul-Henning Kamp "Swap statistics by device"); 2465ec38b344SPoul-Henning Kamp 2466ec38b344SPoul-Henning Kamp /* 24678eb5a1cdSKonstantin Belousov * vmspace_swap_count() - count the approximate swap usage in pages for a 2468ec38b344SPoul-Henning Kamp * vmspace. 2469ec38b344SPoul-Henning Kamp * 2470ec38b344SPoul-Henning Kamp * The map must be locked. 2471ec38b344SPoul-Henning Kamp * 24728eb5a1cdSKonstantin Belousov * Swap usage is determined by taking the proportional swap used by 2473ec38b344SPoul-Henning Kamp * VM objects backing the VM map. To make up for fractional losses, 2474ec38b344SPoul-Henning Kamp * if the VM object has any swap use at all the associated map entries 2475ec38b344SPoul-Henning Kamp * count for at least 1 swap page. 2476ec38b344SPoul-Henning Kamp */ 24772860553aSRebecca Cran long 2478ec38b344SPoul-Henning Kamp vmspace_swap_count(struct vmspace *vmspace) 2479ec38b344SPoul-Henning Kamp { 248065d8409cSRebecca Cran vm_map_t map; 2481ec38b344SPoul-Henning Kamp vm_map_entry_t cur; 248265d8409cSRebecca Cran vm_object_t object; 24832860553aSRebecca Cran long count, n; 248465d8409cSRebecca Cran 248565d8409cSRebecca Cran map = &vmspace->vm_map; 248665d8409cSRebecca Cran count = 0; 2487ec38b344SPoul-Henning Kamp 2488ec38b344SPoul-Henning Kamp for (cur = map->header.next; cur != &map->header; cur = cur->next) { 2489ec38b344SPoul-Henning Kamp if ((cur->eflags & MAP_ENTRY_IS_SUB_MAP) == 0 && 2490ec38b344SPoul-Henning Kamp (object = cur->object.vm_object) != NULL) { 249189f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 2492ec38b344SPoul-Henning Kamp if (object->type == OBJT_SWAP && 2493ec38b344SPoul-Henning Kamp object->un_pager.swp.swp_bcount != 0) { 249465d8409cSRebecca Cran n = (cur->end - cur->start) / PAGE_SIZE; 2495ec38b344SPoul-Henning Kamp count += object->un_pager.swp.swp_bcount * 2496ec38b344SPoul-Henning Kamp SWAP_META_PAGES * n / object->size + 1; 2497ec38b344SPoul-Henning Kamp } 249889f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 2499ec38b344SPoul-Henning Kamp } 2500ec38b344SPoul-Henning Kamp } 2501ec38b344SPoul-Henning Kamp return (count); 2502ec38b344SPoul-Henning Kamp } 2503dee34ca4SPoul-Henning Kamp 2504dee34ca4SPoul-Henning Kamp /* 2505dee34ca4SPoul-Henning Kamp * GEOM backend 2506dee34ca4SPoul-Henning Kamp * 2507dee34ca4SPoul-Henning Kamp * Swapping onto disk devices. 2508dee34ca4SPoul-Henning Kamp * 2509dee34ca4SPoul-Henning Kamp */ 2510dee34ca4SPoul-Henning Kamp 25115721c9c7SPoul-Henning Kamp static g_orphan_t swapgeom_orphan; 25125721c9c7SPoul-Henning Kamp 2513dee34ca4SPoul-Henning Kamp static struct g_class g_swap_class = { 2514dee34ca4SPoul-Henning Kamp .name = "SWAP", 25155721c9c7SPoul-Henning Kamp .version = G_VERSION, 25165721c9c7SPoul-Henning Kamp .orphan = swapgeom_orphan, 2517dee34ca4SPoul-Henning Kamp }; 2518dee34ca4SPoul-Henning Kamp 2519dee34ca4SPoul-Henning Kamp DECLARE_GEOM_CLASS(g_swap_class, g_class); 2520dee34ca4SPoul-Henning Kamp 2521dee34ca4SPoul-Henning Kamp 2522dee34ca4SPoul-Henning Kamp static void 25233398491bSAlexander Motin swapgeom_close_ev(void *arg, int flags) 25243398491bSAlexander Motin { 25253398491bSAlexander Motin struct g_consumer *cp; 25263398491bSAlexander Motin 25273398491bSAlexander Motin cp = arg; 25283398491bSAlexander Motin g_access(cp, -1, -1, 0); 25293398491bSAlexander Motin g_detach(cp); 25303398491bSAlexander Motin g_destroy_consumer(cp); 25313398491bSAlexander Motin } 25323398491bSAlexander Motin 25339e3e3fe5SWarner Losh /* 25349e3e3fe5SWarner Losh * Add a reference to the g_consumer for an inflight transaction. 25359e3e3fe5SWarner Losh */ 25369e3e3fe5SWarner Losh static void 25379e3e3fe5SWarner Losh swapgeom_acquire(struct g_consumer *cp) 25389e3e3fe5SWarner Losh { 25399e3e3fe5SWarner Losh 25409e3e3fe5SWarner Losh mtx_assert(&sw_dev_mtx, MA_OWNED); 25419e3e3fe5SWarner Losh cp->index++; 25429e3e3fe5SWarner Losh } 25439e3e3fe5SWarner Losh 25449e3e3fe5SWarner Losh /* 25450c657d22SKonstantin Belousov * Remove a reference from the g_consumer. Post a close event if all 25460c657d22SKonstantin Belousov * references go away, since the function might be called from the 25470c657d22SKonstantin Belousov * biodone context. 25489e3e3fe5SWarner Losh */ 25499e3e3fe5SWarner Losh static void 25509e3e3fe5SWarner Losh swapgeom_release(struct g_consumer *cp, struct swdevt *sp) 25519e3e3fe5SWarner Losh { 25529e3e3fe5SWarner Losh 25539e3e3fe5SWarner Losh mtx_assert(&sw_dev_mtx, MA_OWNED); 25549e3e3fe5SWarner Losh cp->index--; 25559e3e3fe5SWarner Losh if (cp->index == 0) { 25569e3e3fe5SWarner Losh if (g_post_event(swapgeom_close_ev, cp, M_NOWAIT, NULL) == 0) 25579e3e3fe5SWarner Losh sp->sw_id = NULL; 25589e3e3fe5SWarner Losh } 25599e3e3fe5SWarner Losh } 25609e3e3fe5SWarner Losh 25613398491bSAlexander Motin static void 2562dee34ca4SPoul-Henning Kamp swapgeom_done(struct bio *bp2) 2563dee34ca4SPoul-Henning Kamp { 25643398491bSAlexander Motin struct swdevt *sp; 2565dee34ca4SPoul-Henning Kamp struct buf *bp; 25663398491bSAlexander Motin struct g_consumer *cp; 2567dee34ca4SPoul-Henning Kamp 2568dee34ca4SPoul-Henning Kamp bp = bp2->bio_caller2; 25693398491bSAlexander Motin cp = bp2->bio_from; 2570c5d3d25eSPoul-Henning Kamp bp->b_ioflags = bp2->bio_flags; 2571dee34ca4SPoul-Henning Kamp if (bp2->bio_error) 2572dee34ca4SPoul-Henning Kamp bp->b_ioflags |= BIO_ERROR; 2573c5d3d25eSPoul-Henning Kamp bp->b_resid = bp->b_bcount - bp2->bio_completed; 2574c5d3d25eSPoul-Henning Kamp bp->b_error = bp2->bio_error; 2575dee34ca4SPoul-Henning Kamp bufdone(bp); 25763398491bSAlexander Motin sp = bp2->bio_caller1; 25779e3e3fe5SWarner Losh mtx_lock(&sw_dev_mtx); 25789e3e3fe5SWarner Losh swapgeom_release(cp, sp); 25793398491bSAlexander Motin mtx_unlock(&sw_dev_mtx); 2580dee34ca4SPoul-Henning Kamp g_destroy_bio(bp2); 2581dee34ca4SPoul-Henning Kamp } 2582dee34ca4SPoul-Henning Kamp 2583dee34ca4SPoul-Henning Kamp static void 2584dee34ca4SPoul-Henning Kamp swapgeom_strategy(struct buf *bp, struct swdevt *sp) 2585dee34ca4SPoul-Henning Kamp { 2586dee34ca4SPoul-Henning Kamp struct bio *bio; 2587dee34ca4SPoul-Henning Kamp struct g_consumer *cp; 2588dee34ca4SPoul-Henning Kamp 25893398491bSAlexander Motin mtx_lock(&sw_dev_mtx); 2590dee34ca4SPoul-Henning Kamp cp = sp->sw_id; 2591dee34ca4SPoul-Henning Kamp if (cp == NULL) { 25923398491bSAlexander Motin mtx_unlock(&sw_dev_mtx); 2593dee34ca4SPoul-Henning Kamp bp->b_error = ENXIO; 2594dee34ca4SPoul-Henning Kamp bp->b_ioflags |= BIO_ERROR; 2595dee34ca4SPoul-Henning Kamp bufdone(bp); 2596dee34ca4SPoul-Henning Kamp return; 2597dee34ca4SPoul-Henning Kamp } 25989e3e3fe5SWarner Losh swapgeom_acquire(cp); 25993398491bSAlexander Motin mtx_unlock(&sw_dev_mtx); 260011041003SKonstantin Belousov if (bp->b_iocmd == BIO_WRITE) 260111041003SKonstantin Belousov bio = g_new_bio(); 260211041003SKonstantin Belousov else 26034f8205e5SPoul-Henning Kamp bio = g_alloc_bio(); 26044f8205e5SPoul-Henning Kamp if (bio == NULL) { 26059e3e3fe5SWarner Losh mtx_lock(&sw_dev_mtx); 26069e3e3fe5SWarner Losh swapgeom_release(cp, sp); 26079e3e3fe5SWarner Losh mtx_unlock(&sw_dev_mtx); 26083e5b6861SPoul-Henning Kamp bp->b_error = ENOMEM; 26093e5b6861SPoul-Henning Kamp bp->b_ioflags |= BIO_ERROR; 26103e5b6861SPoul-Henning Kamp bufdone(bp); 26113e5b6861SPoul-Henning Kamp return; 26123e5b6861SPoul-Henning Kamp } 261311041003SKonstantin Belousov 26143398491bSAlexander Motin bio->bio_caller1 = sp; 2615dee34ca4SPoul-Henning Kamp bio->bio_caller2 = bp; 2616c5d3d25eSPoul-Henning Kamp bio->bio_cmd = bp->b_iocmd; 2617dee34ca4SPoul-Henning Kamp bio->bio_offset = (bp->b_blkno - sp->sw_first) * PAGE_SIZE; 2618dee34ca4SPoul-Henning Kamp bio->bio_length = bp->b_bcount; 2619dee34ca4SPoul-Henning Kamp bio->bio_done = swapgeom_done; 2620fade8dd7SJeff Roberson if (!buf_mapped(bp)) { 26212cc718a1SKonstantin Belousov bio->bio_ma = bp->b_pages; 26222cc718a1SKonstantin Belousov bio->bio_data = unmapped_buf; 26232cc718a1SKonstantin Belousov bio->bio_ma_offset = (vm_offset_t)bp->b_offset & PAGE_MASK; 26242cc718a1SKonstantin Belousov bio->bio_ma_n = bp->b_npages; 26252cc718a1SKonstantin Belousov bio->bio_flags |= BIO_UNMAPPED; 26262cc718a1SKonstantin Belousov } else { 26272cc718a1SKonstantin Belousov bio->bio_data = bp->b_data; 26282cc718a1SKonstantin Belousov bio->bio_ma = NULL; 26292cc718a1SKonstantin Belousov } 2630dee34ca4SPoul-Henning Kamp g_io_request(bio, cp); 2631dee34ca4SPoul-Henning Kamp return; 2632dee34ca4SPoul-Henning Kamp } 2633dee34ca4SPoul-Henning Kamp 2634dee34ca4SPoul-Henning Kamp static void 2635dee34ca4SPoul-Henning Kamp swapgeom_orphan(struct g_consumer *cp) 2636dee34ca4SPoul-Henning Kamp { 2637dee34ca4SPoul-Henning Kamp struct swdevt *sp; 26383398491bSAlexander Motin int destroy; 2639dee34ca4SPoul-Henning Kamp 2640dee34ca4SPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 26413398491bSAlexander Motin TAILQ_FOREACH(sp, &swtailq, sw_list) { 26423398491bSAlexander Motin if (sp->sw_id == cp) { 26438f12d83aSAlexander Motin sp->sw_flags |= SW_CLOSING; 26443398491bSAlexander Motin break; 2645dee34ca4SPoul-Henning Kamp } 26463398491bSAlexander Motin } 26479e3e3fe5SWarner Losh /* 26489e3e3fe5SWarner Losh * Drop reference we were created with. Do directly since we're in a 26499e3e3fe5SWarner Losh * special context where we don't have to queue the call to 26509e3e3fe5SWarner Losh * swapgeom_close_ev(). 26519e3e3fe5SWarner Losh */ 26529e3e3fe5SWarner Losh cp->index--; 26533398491bSAlexander Motin destroy = ((sp != NULL) && (cp->index == 0)); 26543398491bSAlexander Motin if (destroy) 26553398491bSAlexander Motin sp->sw_id = NULL; 26563398491bSAlexander Motin mtx_unlock(&sw_dev_mtx); 26573398491bSAlexander Motin if (destroy) 26583398491bSAlexander Motin swapgeom_close_ev(cp, 0); 2659dee34ca4SPoul-Henning Kamp } 2660dee34ca4SPoul-Henning Kamp 2661dee34ca4SPoul-Henning Kamp static void 2662dee34ca4SPoul-Henning Kamp swapgeom_close(struct thread *td, struct swdevt *sw) 2663dee34ca4SPoul-Henning Kamp { 26643398491bSAlexander Motin struct g_consumer *cp; 2665dee34ca4SPoul-Henning Kamp 26663398491bSAlexander Motin mtx_lock(&sw_dev_mtx); 26673398491bSAlexander Motin cp = sw->sw_id; 26683398491bSAlexander Motin sw->sw_id = NULL; 26693398491bSAlexander Motin mtx_unlock(&sw_dev_mtx); 26700c657d22SKonstantin Belousov 26710c657d22SKonstantin Belousov /* 26720c657d22SKonstantin Belousov * swapgeom_close() may be called from the biodone context, 26730c657d22SKonstantin Belousov * where we cannot perform topology changes. Delegate the 26740c657d22SKonstantin Belousov * work to the events thread. 26750c657d22SKonstantin Belousov */ 26763398491bSAlexander Motin if (cp != NULL) 26773398491bSAlexander Motin g_waitfor_event(swapgeom_close_ev, cp, M_WAITOK, NULL); 2678dee34ca4SPoul-Henning Kamp } 2679dee34ca4SPoul-Henning Kamp 268088ad2d7bSKonstantin Belousov static int 268188ad2d7bSKonstantin Belousov swapongeom_locked(struct cdev *dev, struct vnode *vp) 2682dee34ca4SPoul-Henning Kamp { 2683dee34ca4SPoul-Henning Kamp struct g_provider *pp; 2684dee34ca4SPoul-Henning Kamp struct g_consumer *cp; 2685dee34ca4SPoul-Henning Kamp static struct g_geom *gp; 2686dee34ca4SPoul-Henning Kamp struct swdevt *sp; 2687dee34ca4SPoul-Henning Kamp u_long nblks; 2688dee34ca4SPoul-Henning Kamp int error; 2689dee34ca4SPoul-Henning Kamp 269088ad2d7bSKonstantin Belousov pp = g_dev_getprovider(dev); 269188ad2d7bSKonstantin Belousov if (pp == NULL) 269288ad2d7bSKonstantin Belousov return (ENODEV); 2693dee34ca4SPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 2694dee34ca4SPoul-Henning Kamp TAILQ_FOREACH(sp, &swtailq, sw_list) { 2695dee34ca4SPoul-Henning Kamp cp = sp->sw_id; 2696dee34ca4SPoul-Henning Kamp if (cp != NULL && cp->provider == pp) { 2697dee34ca4SPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 269888ad2d7bSKonstantin Belousov return (EBUSY); 2699dee34ca4SPoul-Henning Kamp } 2700dee34ca4SPoul-Henning Kamp } 2701dee34ca4SPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 27025721c9c7SPoul-Henning Kamp if (gp == NULL) 270302c62349SJaakko Heinonen gp = g_new_geomf(&g_swap_class, "swap"); 2704dee34ca4SPoul-Henning Kamp cp = g_new_consumer(gp); 27059e3e3fe5SWarner Losh cp->index = 1; /* Number of active I/Os, plus one for being active. */ 27069e3e3fe5SWarner Losh cp->flags |= G_CF_DIRECT_SEND | G_CF_DIRECT_RECEIVE; 2707dee34ca4SPoul-Henning Kamp g_attach(cp, pp); 2708afeb65e6SPoul-Henning Kamp /* 2709afeb65e6SPoul-Henning Kamp * XXX: Every time you think you can improve the margin for 2710afeb65e6SPoul-Henning Kamp * footshooting, somebody depends on the ability to do so: 2711afeb65e6SPoul-Henning Kamp * savecore(8) wants to write to our swapdev so we cannot 2712afeb65e6SPoul-Henning Kamp * set an exclusive count :-( 2713afeb65e6SPoul-Henning Kamp */ 2714d2bae332SPoul-Henning Kamp error = g_access(cp, 1, 1, 0); 271588ad2d7bSKonstantin Belousov if (error != 0) { 2716dee34ca4SPoul-Henning Kamp g_detach(cp); 2717dee34ca4SPoul-Henning Kamp g_destroy_consumer(cp); 271888ad2d7bSKonstantin Belousov return (error); 2719dee34ca4SPoul-Henning Kamp } 2720dee34ca4SPoul-Henning Kamp nblks = pp->mediasize / DEV_BSIZE; 272188ad2d7bSKonstantin Belousov swaponsomething(vp, cp, nblks, swapgeom_strategy, 272288ad2d7bSKonstantin Belousov swapgeom_close, dev2udev(dev), 27232cc718a1SKonstantin Belousov (pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 ? SW_UNMAPPED : 0); 272488ad2d7bSKonstantin Belousov return (0); 2725dee34ca4SPoul-Henning Kamp } 2726dee34ca4SPoul-Henning Kamp 2727dee34ca4SPoul-Henning Kamp static int 272888ad2d7bSKonstantin Belousov swapongeom(struct vnode *vp) 2729dee34ca4SPoul-Henning Kamp { 2730dee34ca4SPoul-Henning Kamp int error; 2731dee34ca4SPoul-Henning Kamp 2732cb05b60aSAttilio Rao vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 273388ad2d7bSKonstantin Belousov if (vp->v_type != VCHR || (vp->v_iflag & VI_DOOMED) != 0) { 273488ad2d7bSKonstantin Belousov error = ENOENT; 273588ad2d7bSKonstantin Belousov } else { 273688ad2d7bSKonstantin Belousov g_topology_lock(); 273788ad2d7bSKonstantin Belousov error = swapongeom_locked(vp->v_rdev, vp); 273888ad2d7bSKonstantin Belousov g_topology_unlock(); 273988ad2d7bSKonstantin Belousov } 274022db15c0SAttilio Rao VOP_UNLOCK(vp, 0); 2741dee34ca4SPoul-Henning Kamp return (error); 2742dee34ca4SPoul-Henning Kamp } 2743dee34ca4SPoul-Henning Kamp 2744dee34ca4SPoul-Henning Kamp /* 2745dee34ca4SPoul-Henning Kamp * VNODE backend 2746dee34ca4SPoul-Henning Kamp * 2747dee34ca4SPoul-Henning Kamp * This is used mainly for network filesystem (read: probably only tested 2748dee34ca4SPoul-Henning Kamp * with NFS) swapfiles. 2749dee34ca4SPoul-Henning Kamp * 2750dee34ca4SPoul-Henning Kamp */ 2751dee34ca4SPoul-Henning Kamp 2752dee34ca4SPoul-Henning Kamp static void 2753dee34ca4SPoul-Henning Kamp swapdev_strategy(struct buf *bp, struct swdevt *sp) 2754dee34ca4SPoul-Henning Kamp { 2755494eb176SPoul-Henning Kamp struct vnode *vp2; 2756dee34ca4SPoul-Henning Kamp 2757dee34ca4SPoul-Henning Kamp bp->b_blkno = ctodb(bp->b_blkno - sp->sw_first); 2758dee34ca4SPoul-Henning Kamp 2759dee34ca4SPoul-Henning Kamp vp2 = sp->sw_id; 2760dee34ca4SPoul-Henning Kamp vhold(vp2); 2761dee34ca4SPoul-Henning Kamp if (bp->b_iocmd == BIO_WRITE) { 27623cfc7651SOlivier Houchard if (bp->b_bufobj) 2763494eb176SPoul-Henning Kamp bufobj_wdrop(bp->b_bufobj); 2764a76d8f4eSPoul-Henning Kamp bufobj_wref(&vp2->v_bufobj); 2765dee34ca4SPoul-Henning Kamp } 27663cfc7651SOlivier Houchard if (bp->b_bufobj != &vp2->v_bufobj) 27673cfc7651SOlivier Houchard bp->b_bufobj = &vp2->v_bufobj; 2768dee34ca4SPoul-Henning Kamp bp->b_vp = vp2; 27692c18019fSPoul-Henning Kamp bp->b_iooffset = dbtob(bp->b_blkno); 2770b792bebeSPoul-Henning Kamp bstrategy(bp); 2771dee34ca4SPoul-Henning Kamp return; 2772dee34ca4SPoul-Henning Kamp } 2773dee34ca4SPoul-Henning Kamp 2774dee34ca4SPoul-Henning Kamp static void 2775dee34ca4SPoul-Henning Kamp swapdev_close(struct thread *td, struct swdevt *sp) 2776dee34ca4SPoul-Henning Kamp { 2777dee34ca4SPoul-Henning Kamp 2778dee34ca4SPoul-Henning Kamp VOP_CLOSE(sp->sw_vp, FREAD | FWRITE, td->td_ucred, td); 2779dee34ca4SPoul-Henning Kamp vrele(sp->sw_vp); 2780dee34ca4SPoul-Henning Kamp } 2781dee34ca4SPoul-Henning Kamp 2782dee34ca4SPoul-Henning Kamp 2783dee34ca4SPoul-Henning Kamp static int 2784dee34ca4SPoul-Henning Kamp swaponvp(struct thread *td, struct vnode *vp, u_long nblks) 2785dee34ca4SPoul-Henning Kamp { 2786dee34ca4SPoul-Henning Kamp struct swdevt *sp; 2787dee34ca4SPoul-Henning Kamp int error; 2788dee34ca4SPoul-Henning Kamp 2789dee34ca4SPoul-Henning Kamp if (nblks == 0) 2790dee34ca4SPoul-Henning Kamp return (ENXIO); 2791dee34ca4SPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 2792dee34ca4SPoul-Henning Kamp TAILQ_FOREACH(sp, &swtailq, sw_list) { 2793dee34ca4SPoul-Henning Kamp if (sp->sw_id == vp) { 2794dee34ca4SPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 2795dee34ca4SPoul-Henning Kamp return (EBUSY); 2796dee34ca4SPoul-Henning Kamp } 2797dee34ca4SPoul-Henning Kamp } 2798dee34ca4SPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 2799dee34ca4SPoul-Henning Kamp 2800cb05b60aSAttilio Rao (void) vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 2801dee34ca4SPoul-Henning Kamp #ifdef MAC 280230d239bcSRobert Watson error = mac_system_check_swapon(td->td_ucred, vp); 2803dee34ca4SPoul-Henning Kamp if (error == 0) 2804dee34ca4SPoul-Henning Kamp #endif 28059e223287SKonstantin Belousov error = VOP_OPEN(vp, FREAD | FWRITE, td->td_ucred, td, NULL); 280622db15c0SAttilio Rao (void) VOP_UNLOCK(vp, 0); 2807dee34ca4SPoul-Henning Kamp if (error) 2808dee34ca4SPoul-Henning Kamp return (error); 2809dee34ca4SPoul-Henning Kamp 2810dee34ca4SPoul-Henning Kamp swaponsomething(vp, vp, nblks, swapdev_strategy, swapdev_close, 28112cc718a1SKonstantin Belousov NODEV, 0); 2812dee34ca4SPoul-Henning Kamp return (0); 2813dee34ca4SPoul-Henning Kamp } 281489c241d1SGleb Smirnoff 281589c241d1SGleb Smirnoff static int 281689c241d1SGleb Smirnoff sysctl_swap_async_max(SYSCTL_HANDLER_ARGS) 281789c241d1SGleb Smirnoff { 281889c241d1SGleb Smirnoff int error, new, n; 281989c241d1SGleb Smirnoff 282089c241d1SGleb Smirnoff new = nsw_wcount_async_max; 282189c241d1SGleb Smirnoff error = sysctl_handle_int(oidp, &new, 0, req); 282289c241d1SGleb Smirnoff if (error != 0 || req->newptr == NULL) 282389c241d1SGleb Smirnoff return (error); 282489c241d1SGleb Smirnoff 282589c241d1SGleb Smirnoff if (new > nswbuf / 2 || new < 1) 282689c241d1SGleb Smirnoff return (EINVAL); 282789c241d1SGleb Smirnoff 282889c241d1SGleb Smirnoff mtx_lock(&pbuf_mtx); 282989c241d1SGleb Smirnoff while (nsw_wcount_async_max != new) { 283089c241d1SGleb Smirnoff /* 283189c241d1SGleb Smirnoff * Adjust difference. If the current async count is too low, 283289c241d1SGleb Smirnoff * we will need to sqeeze our update slowly in. Sleep with a 283389c241d1SGleb Smirnoff * higher priority than getpbuf() to finish faster. 283489c241d1SGleb Smirnoff */ 283589c241d1SGleb Smirnoff n = new - nsw_wcount_async_max; 283689c241d1SGleb Smirnoff if (nsw_wcount_async + n >= 0) { 283789c241d1SGleb Smirnoff nsw_wcount_async += n; 283889c241d1SGleb Smirnoff nsw_wcount_async_max += n; 283989c241d1SGleb Smirnoff wakeup(&nsw_wcount_async); 284089c241d1SGleb Smirnoff } else { 284189c241d1SGleb Smirnoff nsw_wcount_async_max -= nsw_wcount_async; 284289c241d1SGleb Smirnoff nsw_wcount_async = 0; 284389c241d1SGleb Smirnoff msleep(&nsw_wcount_async, &pbuf_mtx, PSWP, 284489c241d1SGleb Smirnoff "swpsysctl", 0); 284589c241d1SGleb Smirnoff } 284689c241d1SGleb Smirnoff } 284789c241d1SGleb Smirnoff mtx_unlock(&pbuf_mtx); 284889c241d1SGleb Smirnoff 284989c241d1SGleb Smirnoff return (0); 285089c241d1SGleb Smirnoff } 2851