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 72e9c0cc15SPoul-Henning Kamp #include "opt_swap.h" 73e9c0cc15SPoul-Henning Kamp #include "opt_vm.h" 74e9c0cc15SPoul-Henning Kamp 75df8bae1dSRodney W. Grimes #include <sys/param.h> 76df8bae1dSRodney W. Grimes #include <sys/systm.h> 77af647ddeSBruce Evans #include <sys/conf.h> 7864abb5a5SDavid Greenman #include <sys/kernel.h> 79acd3428bSRobert Watson #include <sys/priv.h> 80df8bae1dSRodney W. Grimes #include <sys/proc.h> 819626b608SPoul-Henning Kamp #include <sys/bio.h> 82df8bae1dSRodney W. Grimes #include <sys/buf.h> 83e9c0cc15SPoul-Henning Kamp #include <sys/disk.h> 84e9c0cc15SPoul-Henning Kamp #include <sys/fcntl.h> 85e9c0cc15SPoul-Henning Kamp #include <sys/mount.h> 86e9c0cc15SPoul-Henning Kamp #include <sys/namei.h> 87df8bae1dSRodney W. Grimes #include <sys/vnode.h> 88df8bae1dSRodney W. Grimes #include <sys/malloc.h> 891ba5ad42SEdward Tomasz Napierala #include <sys/racct.h> 903364c323SKonstantin Belousov #include <sys/resource.h> 913364c323SKonstantin Belousov #include <sys/resourcevar.h> 9289f6b863SAttilio Rao #include <sys/rwlock.h> 93327f4e83SMatthew Dillon #include <sys/sysctl.h> 94e9c0cc15SPoul-Henning Kamp #include <sys/sysproto.h> 951c7c3c6aSMatthew Dillon #include <sys/blist.h> 961c7c3c6aSMatthew Dillon #include <sys/lock.h> 970cddd8f0SMatthew Dillon #include <sys/sx.h> 98936524aaSMatthew Dillon #include <sys/vmmeter.h> 99df8bae1dSRodney W. Grimes 100aed55708SRobert Watson #include <security/mac/mac_framework.h> 101aed55708SRobert Watson 102df8bae1dSRodney W. Grimes #include <vm/vm.h> 10321cd6e62SSeigo Tanimura #include <vm/pmap.h> 10421cd6e62SSeigo Tanimura #include <vm/vm_map.h> 10521cd6e62SSeigo Tanimura #include <vm/vm_kern.h> 106efeaf95aSDavid Greenman #include <vm/vm_object.h> 107df8bae1dSRodney W. Grimes #include <vm/vm_page.h> 108efeaf95aSDavid Greenman #include <vm/vm_pager.h> 109df8bae1dSRodney W. Grimes #include <vm/vm_pageout.h> 110e9c0cc15SPoul-Henning Kamp #include <vm/vm_param.h> 111df8bae1dSRodney W. Grimes #include <vm/swap_pager.h> 112efeaf95aSDavid Greenman #include <vm/vm_extern.h> 113670d17b5SJeff Roberson #include <vm/uma.h> 114df8bae1dSRodney W. Grimes 115dee34ca4SPoul-Henning Kamp #include <geom/geom.h> 116dee34ca4SPoul-Henning Kamp 117ec38b344SPoul-Henning Kamp /* 11815523cf7SKonstantin Belousov * SWB_NPAGES must be a power of 2. It may be set to 1, 2, 4, 8, 16 11915523cf7SKonstantin Belousov * or 32 pages per allocation. 12015523cf7SKonstantin Belousov * The 32-page limit is due to the radix code (kern/subr_blist.c). 121ec38b344SPoul-Henning Kamp */ 122ec38b344SPoul-Henning Kamp #ifndef MAX_PAGEOUT_CLUSTER 123ec38b344SPoul-Henning Kamp #define MAX_PAGEOUT_CLUSTER 16 124ec38b344SPoul-Henning Kamp #endif 125ec38b344SPoul-Henning Kamp 126ec38b344SPoul-Henning Kamp #if !defined(SWB_NPAGES) 127ec38b344SPoul-Henning Kamp #define SWB_NPAGES MAX_PAGEOUT_CLUSTER 128ec38b344SPoul-Henning Kamp #endif 129ec38b344SPoul-Henning Kamp 130ec38b344SPoul-Henning Kamp /* 13115523cf7SKonstantin Belousov * The swblock structure maps an object and a small, fixed-size range 13215523cf7SKonstantin Belousov * of page indices to disk addresses within a swap area. 13315523cf7SKonstantin Belousov * The collection of these mappings is implemented as a hash table. 13415523cf7SKonstantin Belousov * Unused disk addresses within a swap area are allocated and managed 13515523cf7SKonstantin Belousov * using a blist. 136ec38b344SPoul-Henning Kamp */ 137ec38b344SPoul-Henning Kamp #define SWCORRECT(n) (sizeof(void *) * (n) / sizeof(daddr_t)) 138ec38b344SPoul-Henning Kamp #define SWAP_META_PAGES (SWB_NPAGES * 2) 139ec38b344SPoul-Henning Kamp #define SWAP_META_MASK (SWAP_META_PAGES - 1) 140ec38b344SPoul-Henning Kamp 141e9c0cc15SPoul-Henning Kamp struct swblock { 142e9c0cc15SPoul-Henning Kamp struct swblock *swb_hnext; 143e9c0cc15SPoul-Henning Kamp vm_object_t swb_object; 144e9c0cc15SPoul-Henning Kamp vm_pindex_t swb_index; 145e9c0cc15SPoul-Henning Kamp int swb_count; 146e9c0cc15SPoul-Henning Kamp daddr_t swb_pages[SWAP_META_PAGES]; 147e9c0cc15SPoul-Henning Kamp }; 148e9c0cc15SPoul-Henning Kamp 1492c4992dbSAlan Cox static MALLOC_DEFINE(M_VMPGDATA, "vm_pgdata", "swap pager private data"); 15020da9c2eSPoul-Henning Kamp static struct mtx sw_dev_mtx; 1518f60c087SPoul-Henning Kamp static TAILQ_HEAD(, swdevt) swtailq = TAILQ_HEAD_INITIALIZER(swtailq); 1528f60c087SPoul-Henning Kamp static struct swdevt *swdevhd; /* Allocate from here next */ 1538f60c087SPoul-Henning Kamp static int nswapdev; /* Number of swap devices */ 1548f60c087SPoul-Henning Kamp int swap_pager_avail; 155e9c0cc15SPoul-Henning Kamp static int swdev_syscall_active = 0; /* serialize swap(on|off) */ 156e9c0cc15SPoul-Henning Kamp 1573364c323SKonstantin Belousov static vm_ooffset_t swap_total; 1588a9c731fSIvan Voras SYSCTL_QUAD(_vm, OID_AUTO, swap_total, CTLFLAG_RD, &swap_total, 0, 1598a9c731fSIvan Voras "Total amount of available swap storage."); 1603364c323SKonstantin Belousov static vm_ooffset_t swap_reserved; 1618a9c731fSIvan Voras SYSCTL_QUAD(_vm, OID_AUTO, swap_reserved, CTLFLAG_RD, &swap_reserved, 0, 1628a9c731fSIvan Voras "Amount of swap storage needed to back all allocated anonymous memory."); 1633364c323SKonstantin Belousov static int overcommit = 0; 1648a9c731fSIvan Voras SYSCTL_INT(_vm, OID_AUTO, overcommit, CTLFLAG_RW, &overcommit, 0, 1658a9c731fSIvan Voras "Configure virtual memory overcommit behavior. See tuning(7) " 1668a9c731fSIvan Voras "for details."); 16761203277SDag-Erling Smørgrav static unsigned long swzone; 16861203277SDag-Erling Smørgrav SYSCTL_ULONG(_vm, OID_AUTO, swzone, CTLFLAG_RD, &swzone, 0, 16961203277SDag-Erling Smørgrav "Actual size of swap metadata zone"); 17061203277SDag-Erling Smørgrav static unsigned long swap_maxpages; 17161203277SDag-Erling Smørgrav SYSCTL_ULONG(_vm, OID_AUTO, swap_maxpages, CTLFLAG_RD, &swap_maxpages, 0, 17261203277SDag-Erling Smørgrav "Maximum amount of swap supported"); 1733364c323SKonstantin Belousov 1743364c323SKonstantin Belousov /* bits from overcommit */ 1753364c323SKonstantin Belousov #define SWAP_RESERVE_FORCE_ON (1 << 0) 1763364c323SKonstantin Belousov #define SWAP_RESERVE_RLIMIT_ON (1 << 1) 1773364c323SKonstantin Belousov #define SWAP_RESERVE_ALLOW_NONWIRED (1 << 2) 1783364c323SKonstantin Belousov 1793364c323SKonstantin Belousov int 1803364c323SKonstantin Belousov swap_reserve(vm_ooffset_t incr) 1813364c323SKonstantin Belousov { 1823364c323SKonstantin Belousov 183ef694c1aSEdward Tomasz Napierala return (swap_reserve_by_cred(incr, curthread->td_ucred)); 1843364c323SKonstantin Belousov } 1853364c323SKonstantin Belousov 1863364c323SKonstantin Belousov int 187ef694c1aSEdward Tomasz Napierala swap_reserve_by_cred(vm_ooffset_t incr, struct ucred *cred) 1883364c323SKonstantin Belousov { 1895c0e1c11SKonstantin Belousov vm_ooffset_t r, s; 1903364c323SKonstantin Belousov int res, error; 1913364c323SKonstantin Belousov static int curfail; 1923364c323SKonstantin Belousov static struct timeval lastfail; 193ef694c1aSEdward Tomasz Napierala struct uidinfo *uip; 194ef694c1aSEdward Tomasz Napierala 195ef694c1aSEdward Tomasz Napierala uip = cred->cr_ruidinfo; 1963364c323SKonstantin Belousov 1973364c323SKonstantin Belousov if (incr & PAGE_MASK) 1983364c323SKonstantin Belousov panic("swap_reserve: & PAGE_MASK"); 1993364c323SKonstantin Belousov 200afcc55f3SEdward Tomasz Napierala #ifdef RACCT 201*4b5c9cf6SEdward Tomasz Napierala if (racct_enable) { 2021ba5ad42SEdward Tomasz Napierala PROC_LOCK(curproc); 2031ba5ad42SEdward Tomasz Napierala error = racct_add(curproc, RACCT_SWAP, incr); 2041ba5ad42SEdward Tomasz Napierala PROC_UNLOCK(curproc); 2051ba5ad42SEdward Tomasz Napierala if (error != 0) 2061ba5ad42SEdward Tomasz Napierala return (0); 207*4b5c9cf6SEdward Tomasz Napierala } 208afcc55f3SEdward Tomasz Napierala #endif 2091ba5ad42SEdward Tomasz Napierala 2103364c323SKonstantin Belousov res = 0; 2113364c323SKonstantin Belousov mtx_lock(&sw_dev_mtx); 2123364c323SKonstantin Belousov r = swap_reserved + incr; 2133364c323SKonstantin Belousov if (overcommit & SWAP_RESERVE_ALLOW_NONWIRED) { 21444f1c916SBryan Drewery s = vm_cnt.v_page_count - vm_cnt.v_free_reserved - vm_cnt.v_wire_count; 2153364c323SKonstantin Belousov s *= PAGE_SIZE; 2163364c323SKonstantin Belousov } else 2173364c323SKonstantin Belousov s = 0; 2183364c323SKonstantin Belousov s += swap_total; 2193364c323SKonstantin Belousov if ((overcommit & SWAP_RESERVE_FORCE_ON) == 0 || r <= s || 2203364c323SKonstantin Belousov (error = priv_check(curthread, PRIV_VM_SWAP_NOQUOTA)) == 0) { 2213364c323SKonstantin Belousov res = 1; 2223364c323SKonstantin Belousov swap_reserved = r; 2233364c323SKonstantin Belousov } 2243364c323SKonstantin Belousov mtx_unlock(&sw_dev_mtx); 2253364c323SKonstantin Belousov 2263364c323SKonstantin Belousov if (res) { 2273364c323SKonstantin Belousov PROC_LOCK(curproc); 2283364c323SKonstantin Belousov UIDINFO_VMSIZE_LOCK(uip); 2295c0e1c11SKonstantin Belousov if ((overcommit & SWAP_RESERVE_RLIMIT_ON) != 0 && 2305c0e1c11SKonstantin Belousov uip->ui_vmsize + incr > lim_cur(curproc, 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 PROC_UNLOCK(curproc); 2373364c323SKonstantin Belousov if (!res) { 2383364c323SKonstantin Belousov mtx_lock(&sw_dev_mtx); 2393364c323SKonstantin Belousov swap_reserved -= incr; 2403364c323SKonstantin Belousov mtx_unlock(&sw_dev_mtx); 2413364c323SKonstantin Belousov } 2423364c323SKonstantin Belousov } 2433364c323SKonstantin Belousov if (!res && ppsratecheck(&lastfail, &curfail, 1)) { 2443364c323SKonstantin Belousov printf("uid %d, pid %d: swap reservation for %jd bytes failed\n", 245134465d7SKonstantin Belousov uip->ui_uid, curproc->p_pid, incr); 2463364c323SKonstantin Belousov } 2473364c323SKonstantin Belousov 248afcc55f3SEdward Tomasz Napierala #ifdef RACCT 2491ba5ad42SEdward Tomasz Napierala if (!res) { 2501ba5ad42SEdward Tomasz Napierala PROC_LOCK(curproc); 2511ba5ad42SEdward Tomasz Napierala racct_sub(curproc, RACCT_SWAP, incr); 2521ba5ad42SEdward Tomasz Napierala PROC_UNLOCK(curproc); 2531ba5ad42SEdward Tomasz Napierala } 254afcc55f3SEdward Tomasz Napierala #endif 2551ba5ad42SEdward Tomasz Napierala 2563364c323SKonstantin Belousov return (res); 2573364c323SKonstantin Belousov } 2583364c323SKonstantin Belousov 2593364c323SKonstantin Belousov void 2603364c323SKonstantin Belousov swap_reserve_force(vm_ooffset_t incr) 2613364c323SKonstantin Belousov { 2623364c323SKonstantin Belousov struct uidinfo *uip; 2633364c323SKonstantin Belousov 2643364c323SKonstantin Belousov mtx_lock(&sw_dev_mtx); 2653364c323SKonstantin Belousov swap_reserved += incr; 2663364c323SKonstantin Belousov mtx_unlock(&sw_dev_mtx); 2673364c323SKonstantin Belousov 268afcc55f3SEdward Tomasz Napierala #ifdef RACCT 2691ba5ad42SEdward Tomasz Napierala PROC_LOCK(curproc); 2701ba5ad42SEdward Tomasz Napierala racct_add_force(curproc, RACCT_SWAP, incr); 2711ba5ad42SEdward Tomasz Napierala PROC_UNLOCK(curproc); 272afcc55f3SEdward Tomasz Napierala #endif 2731ba5ad42SEdward Tomasz Napierala 2743364c323SKonstantin Belousov uip = curthread->td_ucred->cr_ruidinfo; 2753364c323SKonstantin Belousov PROC_LOCK(curproc); 2763364c323SKonstantin Belousov UIDINFO_VMSIZE_LOCK(uip); 2773364c323SKonstantin Belousov uip->ui_vmsize += incr; 2783364c323SKonstantin Belousov UIDINFO_VMSIZE_UNLOCK(uip); 2793364c323SKonstantin Belousov PROC_UNLOCK(curproc); 2803364c323SKonstantin Belousov } 2813364c323SKonstantin Belousov 2823364c323SKonstantin Belousov void 2833364c323SKonstantin Belousov swap_release(vm_ooffset_t decr) 2843364c323SKonstantin Belousov { 285ef694c1aSEdward Tomasz Napierala struct ucred *cred; 2863364c323SKonstantin Belousov 2873364c323SKonstantin Belousov PROC_LOCK(curproc); 288ef694c1aSEdward Tomasz Napierala cred = curthread->td_ucred; 289ef694c1aSEdward Tomasz Napierala swap_release_by_cred(decr, cred); 2903364c323SKonstantin Belousov PROC_UNLOCK(curproc); 2913364c323SKonstantin Belousov } 2923364c323SKonstantin Belousov 2933364c323SKonstantin Belousov void 294ef694c1aSEdward Tomasz Napierala swap_release_by_cred(vm_ooffset_t decr, struct ucred *cred) 2953364c323SKonstantin Belousov { 296ef694c1aSEdward Tomasz Napierala struct uidinfo *uip; 297ef694c1aSEdward Tomasz Napierala 298ef694c1aSEdward Tomasz Napierala uip = cred->cr_ruidinfo; 2993364c323SKonstantin Belousov 3003364c323SKonstantin Belousov if (decr & PAGE_MASK) 3013364c323SKonstantin Belousov panic("swap_release: & PAGE_MASK"); 3023364c323SKonstantin Belousov 3033364c323SKonstantin Belousov mtx_lock(&sw_dev_mtx); 3043364c323SKonstantin Belousov if (swap_reserved < decr) 3053364c323SKonstantin Belousov panic("swap_reserved < decr"); 3063364c323SKonstantin Belousov swap_reserved -= decr; 3073364c323SKonstantin Belousov mtx_unlock(&sw_dev_mtx); 3083364c323SKonstantin Belousov 3093364c323SKonstantin Belousov UIDINFO_VMSIZE_LOCK(uip); 3103364c323SKonstantin Belousov if (uip->ui_vmsize < decr) 3113364c323SKonstantin Belousov printf("negative vmsize for uid = %d\n", uip->ui_uid); 3123364c323SKonstantin Belousov uip->ui_vmsize -= decr; 3133364c323SKonstantin Belousov UIDINFO_VMSIZE_UNLOCK(uip); 3141ba5ad42SEdward Tomasz Napierala 3151ba5ad42SEdward Tomasz Napierala racct_sub_cred(cred, RACCT_SWAP, decr); 3163364c323SKonstantin Belousov } 3173364c323SKonstantin Belousov 3184b03903aSPoul-Henning Kamp static void swapdev_strategy(struct buf *, struct swdevt *sw); 319e9c0cc15SPoul-Henning Kamp 3201c7c3c6aSMatthew Dillon #define SWM_FREE 0x02 /* free, period */ 3211c7c3c6aSMatthew Dillon #define SWM_POP 0x04 /* pop out */ 32226f9a767SRodney W. Grimes 3237dea2c2eSAlan Cox int swap_pager_full = 2; /* swap space exhaustion (task killing) */ 3247dea2c2eSAlan Cox static int swap_pager_almost_full = 1; /* swap space exhaustion (w/hysteresis)*/ 3251c7c3c6aSMatthew Dillon static int nsw_rcount; /* free read buffers */ 326327f4e83SMatthew Dillon static int nsw_wcount_sync; /* limit write buffers / synchronous */ 327327f4e83SMatthew Dillon static int nsw_wcount_async; /* limit write buffers / asynchronous */ 328327f4e83SMatthew Dillon static int nsw_wcount_async_max;/* assigned maximum */ 329327f4e83SMatthew Dillon static int nsw_cluster_max; /* maximum VOP I/O allowed */ 3301c7c3c6aSMatthew Dillon 3311c7c3c6aSMatthew Dillon static struct swblock **swhash; 3321c7c3c6aSMatthew Dillon static int swhash_mask; 3337827d9b0SAlan Cox static struct mtx swhash_mtx; 3347827d9b0SAlan Cox 335327f4e83SMatthew Dillon static int swap_async_max = 4; /* maximum in-progress async I/O's */ 3360cddd8f0SMatthew Dillon static struct sx sw_alloc_sx; 337327f4e83SMatthew Dillon 33824e7ab7cSPoul-Henning Kamp 339327f4e83SMatthew Dillon SYSCTL_INT(_vm, OID_AUTO, swap_async_max, 340327f4e83SMatthew Dillon CTLFLAG_RW, &swap_async_max, 0, "Maximum running async swap ops"); 3411c7c3c6aSMatthew Dillon 3421c7c3c6aSMatthew Dillon /* 3431c7c3c6aSMatthew Dillon * "named" and "unnamed" anon region objects. Try to reduce the overhead 3441c7c3c6aSMatthew Dillon * of searching a named list by hashing it just a little. 3451c7c3c6aSMatthew Dillon */ 3461c7c3c6aSMatthew Dillon 3471c7c3c6aSMatthew Dillon #define NOBJLISTS 8 3481c7c3c6aSMatthew Dillon 3491c7c3c6aSMatthew Dillon #define NOBJLIST(handle) \ 350af647ddeSBruce Evans (&swap_pager_object_list[((int)(intptr_t)handle >> 4) & (NOBJLISTS-1)]) 3511c7c3c6aSMatthew Dillon 352a9fa2c05SAlfred Perlstein static struct mtx sw_alloc_mtx; /* protect list manipulation */ 3531c7c3c6aSMatthew Dillon static struct pagerlst swap_pager_object_list[NOBJLISTS]; 354e9c0cc15SPoul-Henning Kamp static uma_zone_t swap_zone; 3551c7c3c6aSMatthew Dillon 3561c7c3c6aSMatthew Dillon /* 3571c7c3c6aSMatthew Dillon * pagerops for OBJT_SWAP - "swap pager". Some ops are also global procedure 3581c7c3c6aSMatthew Dillon * calls hooked from other parts of the VM system and do not appear here. 3591c7c3c6aSMatthew Dillon * (see vm/swap_pager.h). 3601c7c3c6aSMatthew Dillon */ 361ff98689dSBruce Evans static vm_object_t 36211caded3SAlfred Perlstein swap_pager_alloc(void *handle, vm_ooffset_t size, 3633364c323SKonstantin Belousov vm_prot_t prot, vm_ooffset_t offset, struct ucred *); 36411caded3SAlfred Perlstein static void swap_pager_dealloc(vm_object_t object); 36511caded3SAlfred Perlstein static int swap_pager_getpages(vm_object_t, vm_page_t *, int, int); 36690effb23SGleb Smirnoff static int swap_pager_getpages_async(vm_object_t, vm_page_t *, int, int, 36790effb23SGleb Smirnoff pgo_getpages_iodone_t, void *); 368751221fdSPoul-Henning Kamp static void swap_pager_putpages(vm_object_t, vm_page_t *, int, boolean_t, int *); 3695ea4972cSAlan Cox static boolean_t 3705ea4972cSAlan Cox swap_pager_haspage(vm_object_t object, vm_pindex_t pindex, int *before, int *after); 37111caded3SAlfred Perlstein static void swap_pager_init(void); 37211caded3SAlfred Perlstein static void swap_pager_unswapped(vm_page_t); 373b3fed13eSDavid Schultz static void swap_pager_swapoff(struct swdevt *sp); 374f708ef1bSPoul-Henning Kamp 375df8bae1dSRodney W. Grimes struct pagerops swappagerops = { 376e04e4bacSPoul-Henning Kamp .pgo_init = swap_pager_init, /* early system initialization of pager */ 377e04e4bacSPoul-Henning Kamp .pgo_alloc = swap_pager_alloc, /* allocate an OBJT_SWAP object */ 378e04e4bacSPoul-Henning Kamp .pgo_dealloc = swap_pager_dealloc, /* deallocate an OBJT_SWAP object */ 379e04e4bacSPoul-Henning Kamp .pgo_getpages = swap_pager_getpages, /* pagein */ 38090effb23SGleb Smirnoff .pgo_getpages_async = swap_pager_getpages_async, /* pagein (async) */ 381e04e4bacSPoul-Henning Kamp .pgo_putpages = swap_pager_putpages, /* pageout */ 382e04e4bacSPoul-Henning Kamp .pgo_haspage = swap_pager_haspage, /* get backing store status for page */ 383e04e4bacSPoul-Henning Kamp .pgo_pageunswapped = swap_pager_unswapped, /* remove swap related to page */ 384df8bae1dSRodney W. Grimes }; 385df8bae1dSRodney W. Grimes 3861c7c3c6aSMatthew Dillon /* 3871c7c3c6aSMatthew Dillon * dmmax is in page-sized chunks with the new swap system. It was 38864bcb9c8SMatthew Dillon * dev-bsized chunks in the old. dmmax is always a power of 2. 3891c7c3c6aSMatthew Dillon * 3901c7c3c6aSMatthew Dillon * swap_*() routines are externally accessible. swp_*() routines are 3911c7c3c6aSMatthew Dillon * internal. 3921c7c3c6aSMatthew Dillon */ 393751221fdSPoul-Henning Kamp static int dmmax; 394e9c0cc15SPoul-Henning Kamp static int nswap_lowat = 128; /* in pages, swap_pager_almost_full warn */ 395e9c0cc15SPoul-Henning Kamp static int nswap_hiwat = 512; /* in pages, swap_pager_almost_full warn */ 39626f9a767SRodney W. Grimes 397cee313c4SRobert Watson SYSCTL_INT(_vm, OID_AUTO, dmmax, 398cee313c4SRobert Watson CTLFLAG_RD, &dmmax, 0, "Maximum size of a swap block"); 399cee313c4SRobert Watson 400a5edd34aSPoul-Henning Kamp static void swp_sizecheck(void); 40111caded3SAlfred Perlstein static void swp_pager_async_iodone(struct buf *bp); 402dee34ca4SPoul-Henning Kamp static int swapongeom(struct thread *, struct vnode *); 40359efee01SPoul-Henning Kamp static int swaponvp(struct thread *, struct vnode *, u_long); 40435918c55SChristian S.J. Peron static int swapoff_one(struct swdevt *sp, struct ucred *cred); 40524a1cce3SDavid Greenman 4061c7c3c6aSMatthew Dillon /* 4071c7c3c6aSMatthew Dillon * Swap bitmap functions 4081c7c3c6aSMatthew Dillon */ 409a5edd34aSPoul-Henning Kamp static void swp_pager_freeswapspace(daddr_t blk, int npages); 410a5edd34aSPoul-Henning Kamp static daddr_t swp_pager_getswapspace(int npages); 4111c7c3c6aSMatthew Dillon 4121c7c3c6aSMatthew Dillon /* 4131c7c3c6aSMatthew Dillon * Metadata functions 4141c7c3c6aSMatthew Dillon */ 415a5edd34aSPoul-Henning Kamp static struct swblock **swp_pager_hash(vm_object_t object, vm_pindex_t index); 41611caded3SAlfred Perlstein static void swp_pager_meta_build(vm_object_t, vm_pindex_t, daddr_t); 41711caded3SAlfred Perlstein static void swp_pager_meta_free(vm_object_t, vm_pindex_t, daddr_t); 41811caded3SAlfred Perlstein static void swp_pager_meta_free_all(vm_object_t); 41911caded3SAlfred Perlstein static daddr_t swp_pager_meta_ctl(vm_object_t, vm_pindex_t, int); 4201c7c3c6aSMatthew Dillon 421e86a87e9SKonstantin Belousov static void 422e86a87e9SKonstantin Belousov swp_pager_free_nrpage(vm_page_t m) 423e86a87e9SKonstantin Belousov { 424e86a87e9SKonstantin Belousov 4253c4a2440SAlan Cox vm_page_lock(m); 426e86a87e9SKonstantin Belousov if (m->wire_count == 0) 427e86a87e9SKonstantin Belousov vm_page_free(m); 4283c4a2440SAlan Cox vm_page_unlock(m); 429e86a87e9SKonstantin Belousov } 430e86a87e9SKonstantin Belousov 4311c7c3c6aSMatthew Dillon /* 4321c7c3c6aSMatthew Dillon * SWP_SIZECHECK() - update swap_pager_full indication 4331c7c3c6aSMatthew Dillon * 43420d3034fSMatthew Dillon * update the swap_pager_almost_full indication and warn when we are 43520d3034fSMatthew Dillon * about to run out of swap space, using lowat/hiwat hysteresis. 43620d3034fSMatthew Dillon * 43720d3034fSMatthew Dillon * Clear swap_pager_full ( task killing ) indication when lowat is met. 4381c7c3c6aSMatthew Dillon * 4391c7c3c6aSMatthew Dillon * No restrictions on call 4401c7c3c6aSMatthew Dillon * This routine may not block. 4411c7c3c6aSMatthew Dillon */ 442a5edd34aSPoul-Henning Kamp static void 4432f249180SPoul-Henning Kamp swp_sizecheck(void) 4440d94caffSDavid Greenman { 44523955314SAlfred Perlstein 4468f60c087SPoul-Henning Kamp if (swap_pager_avail < nswap_lowat) { 44720d3034fSMatthew Dillon if (swap_pager_almost_full == 0) { 4481af87c92SDavid Greenman printf("swap_pager: out of swap space\n"); 44920d3034fSMatthew Dillon swap_pager_almost_full = 1; 4502b0d37a4SMatthew Dillon } 45120d3034fSMatthew Dillon } else { 45226f9a767SRodney W. Grimes swap_pager_full = 0; 4538f60c087SPoul-Henning Kamp if (swap_pager_avail > nswap_hiwat) 45420d3034fSMatthew Dillon swap_pager_almost_full = 0; 45526f9a767SRodney W. Grimes } 4561c7c3c6aSMatthew Dillon } 4571c7c3c6aSMatthew Dillon 4581c7c3c6aSMatthew Dillon /* 459da5fd145SPeter Wemm * SWP_PAGER_HASH() - hash swap meta data 460da5fd145SPeter Wemm * 461a5edd34aSPoul-Henning Kamp * This is an helper function which hashes the swapblk given 462da5fd145SPeter Wemm * the object and page index. It returns a pointer to a pointer 463da5fd145SPeter Wemm * to the object, or a pointer to a NULL pointer if it could not 464da5fd145SPeter Wemm * find a swapblk. 465da5fd145SPeter Wemm */ 466a5edd34aSPoul-Henning Kamp static struct swblock ** 467da5fd145SPeter Wemm swp_pager_hash(vm_object_t object, vm_pindex_t index) 468da5fd145SPeter Wemm { 469da5fd145SPeter Wemm struct swblock **pswap; 470da5fd145SPeter Wemm struct swblock *swap; 471da5fd145SPeter Wemm 472da5fd145SPeter Wemm index &= ~(vm_pindex_t)SWAP_META_MASK; 473da5fd145SPeter Wemm pswap = &swhash[(index ^ (int)(intptr_t)object) & swhash_mask]; 474da5fd145SPeter Wemm while ((swap = *pswap) != NULL) { 475da5fd145SPeter Wemm if (swap->swb_object == object && 476da5fd145SPeter Wemm swap->swb_index == index 477da5fd145SPeter Wemm ) { 478da5fd145SPeter Wemm break; 479da5fd145SPeter Wemm } 480da5fd145SPeter Wemm pswap = &swap->swb_hnext; 481da5fd145SPeter Wemm } 482da5fd145SPeter Wemm return (pswap); 483da5fd145SPeter Wemm } 484da5fd145SPeter Wemm 485da5fd145SPeter Wemm /* 4861c7c3c6aSMatthew Dillon * SWAP_PAGER_INIT() - initialize the swap pager! 4871c7c3c6aSMatthew Dillon * 4881c7c3c6aSMatthew Dillon * Expected to be started from system init. NOTE: This code is run 4891c7c3c6aSMatthew Dillon * before much else so be careful what you depend on. Most of the VM 4901c7c3c6aSMatthew Dillon * system has yet to be initialized at this point. 4911c7c3c6aSMatthew Dillon */ 492f5a12711SPoul-Henning Kamp static void 4932f249180SPoul-Henning Kamp swap_pager_init(void) 494df8bae1dSRodney W. Grimes { 4951c7c3c6aSMatthew Dillon /* 4961c7c3c6aSMatthew Dillon * Initialize object lists 4971c7c3c6aSMatthew Dillon */ 4981c7c3c6aSMatthew Dillon int i; 4991c7c3c6aSMatthew Dillon 5001c7c3c6aSMatthew Dillon for (i = 0; i < NOBJLISTS; ++i) 5011c7c3c6aSMatthew Dillon TAILQ_INIT(&swap_pager_object_list[i]); 5026008862bSJohn Baldwin mtx_init(&sw_alloc_mtx, "swap_pager list", NULL, MTX_DEF); 50320da9c2eSPoul-Henning Kamp mtx_init(&sw_dev_mtx, "swapdev", NULL, MTX_DEF); 504df8bae1dSRodney W. Grimes 505df8bae1dSRodney W. Grimes /* 5061c7c3c6aSMatthew Dillon * Device Stripe, in PAGE_SIZE'd blocks 507df8bae1dSRodney W. Grimes */ 5081c7c3c6aSMatthew Dillon dmmax = SWB_NPAGES * 2; 5091c7c3c6aSMatthew Dillon } 51026f9a767SRodney W. Grimes 511df8bae1dSRodney W. Grimes /* 5121c7c3c6aSMatthew Dillon * SWAP_PAGER_SWAP_INIT() - swap pager initialization from pageout process 5131c7c3c6aSMatthew Dillon * 5141c7c3c6aSMatthew Dillon * Expected to be started from pageout process once, prior to entering 5151c7c3c6aSMatthew Dillon * its main loop. 516df8bae1dSRodney W. Grimes */ 51724a1cce3SDavid Greenman void 5182f249180SPoul-Henning Kamp swap_pager_swap_init(void) 519df8bae1dSRodney W. Grimes { 52061203277SDag-Erling Smørgrav unsigned long n, n2; 5210d94caffSDavid Greenman 52226f9a767SRodney W. Grimes /* 5231c7c3c6aSMatthew Dillon * Number of in-transit swap bp operations. Don't 5241c7c3c6aSMatthew Dillon * exhaust the pbufs completely. Make sure we 5251c7c3c6aSMatthew Dillon * initialize workable values (0 will work for hysteresis 5261c7c3c6aSMatthew Dillon * but it isn't very efficient). 5271c7c3c6aSMatthew Dillon * 528327f4e83SMatthew Dillon * The nsw_cluster_max is constrained by the bp->b_pages[] 5291c7c3c6aSMatthew Dillon * array (MAXPHYS/PAGE_SIZE) and our locally defined 5301c7c3c6aSMatthew Dillon * MAX_PAGEOUT_CLUSTER. Also be aware that swap ops are 5311c7c3c6aSMatthew Dillon * constrained by the swap device interleave stripe size. 532327f4e83SMatthew Dillon * 533327f4e83SMatthew Dillon * Currently we hardwire nsw_wcount_async to 4. This limit is 534327f4e83SMatthew Dillon * designed to prevent other I/O from having high latencies due to 535327f4e83SMatthew Dillon * our pageout I/O. The value 4 works well for one or two active swap 536327f4e83SMatthew Dillon * devices but is probably a little low if you have more. Even so, 537327f4e83SMatthew Dillon * a higher value would probably generate only a limited improvement 538327f4e83SMatthew Dillon * with three or four active swap devices since the system does not 539327f4e83SMatthew Dillon * typically have to pageout at extreme bandwidths. We will want 540327f4e83SMatthew Dillon * at least 2 per swap devices, and 4 is a pretty good value if you 541327f4e83SMatthew Dillon * have one NFS swap device due to the command/ack latency over NFS. 542327f4e83SMatthew Dillon * So it all works out pretty well. 54326f9a767SRodney W. Grimes */ 544ad3cce20SMatthew Dillon nsw_cluster_max = min((MAXPHYS/PAGE_SIZE), MAX_PAGEOUT_CLUSTER); 545327f4e83SMatthew Dillon 5466d541bf1SJohn Baldwin mtx_lock(&pbuf_mtx); 5471c7c3c6aSMatthew Dillon nsw_rcount = (nswbuf + 1) / 2; 548327f4e83SMatthew Dillon nsw_wcount_sync = (nswbuf + 3) / 4; 549327f4e83SMatthew Dillon nsw_wcount_async = 4; 550327f4e83SMatthew Dillon nsw_wcount_async_max = nsw_wcount_async; 5516d541bf1SJohn Baldwin mtx_unlock(&pbuf_mtx); 55224a1cce3SDavid Greenman 5531c7c3c6aSMatthew Dillon /* 5541c7c3c6aSMatthew Dillon * Initialize our zone. Right now I'm just guessing on the number 5551c7c3c6aSMatthew Dillon * we need based on the number of pages in the system. Each swblock 55661203277SDag-Erling Smørgrav * can hold 32 pages, so this is probably overkill. This reservation 557ec61f55dSMatthew Dillon * is typically limited to around 32MB by default. 5581c7c3c6aSMatthew Dillon */ 55944f1c916SBryan Drewery n = vm_cnt.v_page_count / 2; 5602f9e4e80SMatthew Dillon if (maxswzone && n > maxswzone / sizeof(struct swblock)) 5612f9e4e80SMatthew Dillon n = maxswzone / sizeof(struct swblock); 56222a5e6b9SDag-Erling Smørgrav n2 = n; 563670d17b5SJeff Roberson swap_zone = uma_zcreate("SWAPMETA", sizeof(struct swblock), NULL, NULL, 5647827d9b0SAlan Cox NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE | UMA_ZONE_VM); 565010b1ca1SDavid Schultz if (swap_zone == NULL) 566010b1ca1SDavid Schultz panic("failed to create swap_zone."); 5678355f576SJeff Roberson do { 568a4915c21SAttilio Rao if (uma_zone_reserve_kva(swap_zone, n)) 56961ce6eeeSAlfred Perlstein break; 57061ce6eeeSAlfred Perlstein /* 57161ce6eeeSAlfred Perlstein * if the allocation failed, try a zone two thirds the 57261ce6eeeSAlfred Perlstein * size of the previous attempt. 57361ce6eeeSAlfred Perlstein */ 57461ce6eeeSAlfred Perlstein n -= ((n + 2) / 3); 57561ce6eeeSAlfred Perlstein } while (n > 0); 57621cd6e62SSeigo Tanimura if (n2 != n) 57761203277SDag-Erling Smørgrav printf("Swap zone entries reduced from %lu to %lu.\n", n2, n); 57861203277SDag-Erling Smørgrav swap_maxpages = n * SWAP_META_PAGES; 57961203277SDag-Erling Smørgrav swzone = n * sizeof(struct swblock); 58022a5e6b9SDag-Erling Smørgrav n2 = n; 58124a1cce3SDavid Greenman 5821c7c3c6aSMatthew Dillon /* 5831c7c3c6aSMatthew Dillon * Initialize our meta-data hash table. The swapper does not need to 5841c7c3c6aSMatthew Dillon * be quite as efficient as the VM system, so we do not use an 5851c7c3c6aSMatthew Dillon * oversized hash table. 5861c7c3c6aSMatthew Dillon * 5871c7c3c6aSMatthew Dillon * n: size of hash table, must be power of 2 5881c7c3c6aSMatthew Dillon * swhash_mask: hash table index mask 5891c7c3c6aSMatthew Dillon */ 59061ce6eeeSAlfred Perlstein for (n = 1; n < n2 / 8; n *= 2) 5911c7c3c6aSMatthew Dillon ; 592a163d034SWarner Losh swhash = malloc(sizeof(struct swblock *) * n, M_VMPGDATA, M_WAITOK | M_ZERO); 5931c7c3c6aSMatthew Dillon swhash_mask = n - 1; 5947827d9b0SAlan Cox mtx_init(&swhash_mtx, "swap_pager swhash", NULL, MTX_DEF); 59524a1cce3SDavid Greenman } 59624a1cce3SDavid Greenman 59724a1cce3SDavid Greenman /* 5981c7c3c6aSMatthew Dillon * SWAP_PAGER_ALLOC() - allocate a new OBJT_SWAP VM object and instantiate 5991c7c3c6aSMatthew Dillon * its metadata structures. 6001c7c3c6aSMatthew Dillon * 6011c7c3c6aSMatthew Dillon * This routine is called from the mmap and fork code to create a new 6021c7c3c6aSMatthew Dillon * OBJT_SWAP object. We do this by creating an OBJT_DEFAULT object 6031c7c3c6aSMatthew Dillon * and then converting it with swp_pager_meta_build(). 6041c7c3c6aSMatthew Dillon * 6051c7c3c6aSMatthew Dillon * This routine may block in vm_object_allocate() and create a named 606cec9f109SDavid E. O'Brien * object lookup race, so we must interlock. 60724c46d03SAlan Cox * 60824c46d03SAlan Cox * MPSAFE 60924a1cce3SDavid Greenman */ 610f5a12711SPoul-Henning Kamp static vm_object_t 6116cde7a16SDavid Greenman swap_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, 6123364c323SKonstantin Belousov vm_ooffset_t offset, struct ucred *cred) 61324a1cce3SDavid Greenman { 61424a1cce3SDavid Greenman vm_object_t object; 6152f7af3dbSAlan Cox vm_pindex_t pindex; 6162f7af3dbSAlan Cox 6172f7af3dbSAlan Cox pindex = OFF_TO_IDX(offset + PAGE_MASK + size); 61824a1cce3SDavid Greenman if (handle) { 619e793b779SAlan Cox mtx_lock(&Giant); 6201c7c3c6aSMatthew Dillon /* 6211c7c3c6aSMatthew Dillon * Reference existing named region or allocate new one. There 6221c7c3c6aSMatthew Dillon * should not be a race here against swp_pager_meta_build() 6231c7c3c6aSMatthew Dillon * as called from vm_page_remove() in regards to the lookup 6241c7c3c6aSMatthew Dillon * of the handle. 6251c7c3c6aSMatthew Dillon */ 6260cddd8f0SMatthew Dillon sx_xlock(&sw_alloc_sx); 6271c7c3c6aSMatthew Dillon object = vm_pager_object_lookup(NOBJLIST(handle), handle); 628b5e8f167SAlan Cox if (object == NULL) { 6293364c323SKonstantin Belousov if (cred != NULL) { 630ef694c1aSEdward Tomasz Napierala if (!swap_reserve_by_cred(size, cred)) { 6313364c323SKonstantin Belousov sx_xunlock(&sw_alloc_sx); 6323364c323SKonstantin Belousov mtx_unlock(&Giant); 6333364c323SKonstantin Belousov return (NULL); 6343364c323SKonstantin Belousov } 635ef694c1aSEdward Tomasz Napierala crhold(cred); 6363364c323SKonstantin Belousov } 6372f7af3dbSAlan Cox object = vm_object_allocate(OBJT_DEFAULT, pindex); 63889f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 6393364c323SKonstantin Belousov object->handle = handle; 6403364c323SKonstantin Belousov if (cred != NULL) { 641ef694c1aSEdward Tomasz Napierala object->cred = cred; 6423364c323SKonstantin Belousov object->charge = size; 6433364c323SKonstantin Belousov } 6444dcc5c2dSMatthew Dillon swp_pager_meta_build(object, 0, SWAPBLK_NONE); 64589f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 64624a1cce3SDavid Greenman } 6470cddd8f0SMatthew Dillon sx_xunlock(&sw_alloc_sx); 648e793b779SAlan Cox mtx_unlock(&Giant); 64924a1cce3SDavid Greenman } else { 6503364c323SKonstantin Belousov if (cred != NULL) { 651ef694c1aSEdward Tomasz Napierala if (!swap_reserve_by_cred(size, cred)) 6523364c323SKonstantin Belousov return (NULL); 653ef694c1aSEdward Tomasz Napierala crhold(cred); 6543364c323SKonstantin Belousov } 6552f7af3dbSAlan Cox object = vm_object_allocate(OBJT_DEFAULT, pindex); 65689f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 6573364c323SKonstantin Belousov if (cred != NULL) { 658ef694c1aSEdward Tomasz Napierala object->cred = cred; 6593364c323SKonstantin Belousov object->charge = size; 6603364c323SKonstantin Belousov } 6614dcc5c2dSMatthew Dillon swp_pager_meta_build(object, 0, SWAPBLK_NONE); 66289f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 66324a1cce3SDavid Greenman } 66424a1cce3SDavid Greenman return (object); 665df8bae1dSRodney W. Grimes } 666df8bae1dSRodney W. Grimes 66726f9a767SRodney W. Grimes /* 6681c7c3c6aSMatthew Dillon * SWAP_PAGER_DEALLOC() - remove swap metadata from object 6691c7c3c6aSMatthew Dillon * 6701c7c3c6aSMatthew Dillon * The swap backing for the object is destroyed. The code is 6711c7c3c6aSMatthew Dillon * designed such that we can reinstantiate it later, but this 6721c7c3c6aSMatthew Dillon * routine is typically called only when the entire object is 6731c7c3c6aSMatthew Dillon * about to be destroyed. 6741c7c3c6aSMatthew Dillon * 67515523cf7SKonstantin Belousov * The object must be locked. 67626f9a767SRodney W. Grimes */ 677df8bae1dSRodney W. Grimes static void 6782f249180SPoul-Henning Kamp swap_pager_dealloc(vm_object_t object) 67926f9a767SRodney W. Grimes { 6804dcc5c2dSMatthew Dillon 68126f9a767SRodney W. Grimes /* 6821c7c3c6aSMatthew Dillon * Remove from list right away so lookups will fail if we block for 6831c7c3c6aSMatthew Dillon * pageout completion. 68426f9a767SRodney W. Grimes */ 685bd228075SAlan Cox if (object->handle != NULL) { 686a9fa2c05SAlfred Perlstein mtx_lock(&sw_alloc_mtx); 6871c7c3c6aSMatthew Dillon TAILQ_REMOVE(NOBJLIST(object->handle), object, pager_object_list); 688a9fa2c05SAlfred Perlstein mtx_unlock(&sw_alloc_mtx); 689bd228075SAlan Cox } 6901c7c3c6aSMatthew Dillon 69189f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(object); 6921c7c3c6aSMatthew Dillon vm_object_pip_wait(object, "swpdea"); 6931c7c3c6aSMatthew Dillon 6941c7c3c6aSMatthew Dillon /* 6951c7c3c6aSMatthew Dillon * Free all remaining metadata. We only bother to free it from 6961c7c3c6aSMatthew Dillon * the swap meta data. We do not attempt to free swapblk's still 6971c7c3c6aSMatthew Dillon * associated with vm_page_t's for this object. We do not care 6981c7c3c6aSMatthew Dillon * if paging is still in progress on some objects. 6991c7c3c6aSMatthew Dillon */ 7001c7c3c6aSMatthew Dillon swp_pager_meta_free_all(object); 7011c7c3c6aSMatthew Dillon } 7021c7c3c6aSMatthew Dillon 7031c7c3c6aSMatthew Dillon /************************************************************************ 7041c7c3c6aSMatthew Dillon * SWAP PAGER BITMAP ROUTINES * 7051c7c3c6aSMatthew Dillon ************************************************************************/ 7061c7c3c6aSMatthew Dillon 7071c7c3c6aSMatthew Dillon /* 7081c7c3c6aSMatthew Dillon * SWP_PAGER_GETSWAPSPACE() - allocate raw swap space 7091c7c3c6aSMatthew Dillon * 7101c7c3c6aSMatthew Dillon * Allocate swap for the requested number of pages. The starting 7111c7c3c6aSMatthew Dillon * swap block number (a page index) is returned or SWAPBLK_NONE 7121c7c3c6aSMatthew Dillon * if the allocation failed. 7131c7c3c6aSMatthew Dillon * 7141c7c3c6aSMatthew Dillon * Also has the side effect of advising that somebody made a mistake 7151c7c3c6aSMatthew Dillon * when they configured swap and didn't configure enough. 7161c7c3c6aSMatthew Dillon * 71715523cf7SKonstantin Belousov * This routine may not sleep. 7188f60c087SPoul-Henning Kamp * 7198f60c087SPoul-Henning Kamp * We allocate in round-robin fashion from the configured devices. 7201c7c3c6aSMatthew Dillon */ 721a5edd34aSPoul-Henning Kamp static daddr_t 7222f249180SPoul-Henning Kamp swp_pager_getswapspace(int npages) 7231c7c3c6aSMatthew Dillon { 7241c7c3c6aSMatthew Dillon daddr_t blk; 7258f60c087SPoul-Henning Kamp struct swdevt *sp; 7268f60c087SPoul-Henning Kamp int i; 7271c7c3c6aSMatthew Dillon 7288f60c087SPoul-Henning Kamp blk = SWAPBLK_NONE; 72920da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 7308f60c087SPoul-Henning Kamp sp = swdevhd; 7318f60c087SPoul-Henning Kamp for (i = 0; i < nswapdev; i++) { 7328f60c087SPoul-Henning Kamp if (sp == NULL) 7338f60c087SPoul-Henning Kamp sp = TAILQ_FIRST(&swtailq); 7348f60c087SPoul-Henning Kamp if (!(sp->sw_flags & SW_CLOSING)) { 7358f60c087SPoul-Henning Kamp blk = blist_alloc(sp->sw_blist, npages); 7368f60c087SPoul-Henning Kamp if (blk != SWAPBLK_NONE) { 7378f60c087SPoul-Henning Kamp blk += sp->sw_first; 7388f60c087SPoul-Henning Kamp sp->sw_used += npages; 739d05bc129SAlan Cox swap_pager_avail -= npages; 7408f60c087SPoul-Henning Kamp swp_sizecheck(); 7418f60c087SPoul-Henning Kamp swdevhd = TAILQ_NEXT(sp, sw_list); 742d05bc129SAlan Cox goto done; 7438f60c087SPoul-Henning Kamp } 7448f60c087SPoul-Henning Kamp } 7458f60c087SPoul-Henning Kamp sp = TAILQ_NEXT(sp, sw_list); 7468f60c087SPoul-Henning Kamp } 7472b0d37a4SMatthew Dillon if (swap_pager_full != 2) { 74820da9c2eSPoul-Henning Kamp printf("swap_pager_getswapspace(%d): failed\n", npages); 7492b0d37a4SMatthew Dillon swap_pager_full = 2; 75020d3034fSMatthew Dillon swap_pager_almost_full = 1; 7512b0d37a4SMatthew Dillon } 7528f60c087SPoul-Henning Kamp swdevhd = NULL; 753d05bc129SAlan Cox done: 754d05bc129SAlan Cox mtx_unlock(&sw_dev_mtx); 7551c7c3c6aSMatthew Dillon return (blk); 75626f9a767SRodney W. Grimes } 75726f9a767SRodney W. Grimes 758b3fed13eSDavid Schultz static int 759b3fed13eSDavid Schultz swp_pager_isondev(daddr_t blk, struct swdevt *sp) 7608f60c087SPoul-Henning Kamp { 7618f60c087SPoul-Henning Kamp 762b3fed13eSDavid Schultz return (blk >= sp->sw_first && blk < sp->sw_end); 7638f60c087SPoul-Henning Kamp } 7648f60c087SPoul-Henning Kamp 7654b03903aSPoul-Henning Kamp static void 7664b03903aSPoul-Henning Kamp swp_pager_strategy(struct buf *bp) 7674b03903aSPoul-Henning Kamp { 7684b03903aSPoul-Henning Kamp struct swdevt *sp; 7694b03903aSPoul-Henning Kamp 77020da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 7714b03903aSPoul-Henning Kamp TAILQ_FOREACH(sp, &swtailq, sw_list) { 7724b03903aSPoul-Henning Kamp if (bp->b_blkno >= sp->sw_first && bp->b_blkno < sp->sw_end) { 77320da9c2eSPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 7742cc718a1SKonstantin Belousov if ((sp->sw_flags & SW_UNMAPPED) != 0 && 7752cc718a1SKonstantin Belousov unmapped_buf_allowed) { 7762cc718a1SKonstantin Belousov bp->b_kvaalloc = bp->b_data; 7772cc718a1SKonstantin Belousov bp->b_data = unmapped_buf; 7782cc718a1SKonstantin Belousov bp->b_kvabase = unmapped_buf; 7792cc718a1SKonstantin Belousov bp->b_offset = 0; 7802cc718a1SKonstantin Belousov bp->b_flags |= B_UNMAPPED; 7812cc718a1SKonstantin Belousov } else { 7822cc718a1SKonstantin Belousov pmap_qenter((vm_offset_t)bp->b_data, 7832cc718a1SKonstantin Belousov &bp->b_pages[0], bp->b_bcount / PAGE_SIZE); 7842cc718a1SKonstantin Belousov } 7854b03903aSPoul-Henning Kamp sp->sw_strategy(bp, sp); 7864b03903aSPoul-Henning Kamp return; 7874b03903aSPoul-Henning Kamp } 7884b03903aSPoul-Henning Kamp } 78920da9c2eSPoul-Henning Kamp panic("Swapdev not found"); 7904b03903aSPoul-Henning Kamp } 7914b03903aSPoul-Henning Kamp 7928f60c087SPoul-Henning Kamp 79326f9a767SRodney W. Grimes /* 7941c7c3c6aSMatthew Dillon * SWP_PAGER_FREESWAPSPACE() - free raw swap space 7951c7c3c6aSMatthew Dillon * 7961c7c3c6aSMatthew Dillon * This routine returns the specified swap blocks back to the bitmap. 7971c7c3c6aSMatthew Dillon * 79815523cf7SKonstantin Belousov * This routine may not sleep. 79926f9a767SRodney W. Grimes */ 800a5edd34aSPoul-Henning Kamp static void 8018f60c087SPoul-Henning Kamp swp_pager_freeswapspace(daddr_t blk, int npages) 8020d94caffSDavid Greenman { 8038f60c087SPoul-Henning Kamp struct swdevt *sp; 80492da00bbSMatthew Dillon 8057645e885SAlan Cox mtx_lock(&sw_dev_mtx); 8067645e885SAlan Cox TAILQ_FOREACH(sp, &swtailq, sw_list) { 8077645e885SAlan Cox if (blk >= sp->sw_first && blk < sp->sw_end) { 80892da00bbSMatthew Dillon sp->sw_used -= npages; 80992da00bbSMatthew Dillon /* 8107645e885SAlan Cox * If we are attempting to stop swapping on 8117645e885SAlan Cox * this device, we don't want to mark any 8127645e885SAlan Cox * blocks free lest they be reused. 81392da00bbSMatthew Dillon */ 8147645e885SAlan Cox if ((sp->sw_flags & SW_CLOSING) == 0) { 8157645e885SAlan Cox blist_free(sp->sw_blist, blk - sp->sw_first, 8167645e885SAlan Cox npages); 8178f60c087SPoul-Henning Kamp swap_pager_avail += npages; 8181c7c3c6aSMatthew Dillon swp_sizecheck(); 81926f9a767SRodney W. Grimes } 8207645e885SAlan Cox mtx_unlock(&sw_dev_mtx); 8217645e885SAlan Cox return; 8227645e885SAlan Cox } 8237645e885SAlan Cox } 8247645e885SAlan Cox panic("Swapdev not found"); 8257645e885SAlan Cox } 8261c7c3c6aSMatthew Dillon 82726f9a767SRodney W. Grimes /* 8281c7c3c6aSMatthew Dillon * SWAP_PAGER_FREESPACE() - frees swap blocks associated with a page 8291c7c3c6aSMatthew Dillon * range within an object. 8301c7c3c6aSMatthew Dillon * 8311c7c3c6aSMatthew Dillon * This is a globally accessible routine. 8321c7c3c6aSMatthew Dillon * 8331c7c3c6aSMatthew Dillon * This routine removes swapblk assignments from swap metadata. 8341c7c3c6aSMatthew Dillon * 8351c7c3c6aSMatthew Dillon * The external callers of this routine typically have already destroyed 8361c7c3c6aSMatthew Dillon * or renamed vm_page_t's associated with this range in the object so 8371c7c3c6aSMatthew Dillon * we should be ok. 838c25673ffSAttilio Rao * 839c25673ffSAttilio Rao * The object must be locked. 84026f9a767SRodney W. Grimes */ 84126f9a767SRodney W. Grimes void 8422f249180SPoul-Henning Kamp swap_pager_freespace(vm_object_t object, vm_pindex_t start, vm_size_t size) 84326f9a767SRodney W. Grimes { 84423955314SAlfred Perlstein 8451c7c3c6aSMatthew Dillon swp_pager_meta_free(object, start, size); 8464dcc5c2dSMatthew Dillon } 8474dcc5c2dSMatthew Dillon 8484dcc5c2dSMatthew Dillon /* 8494dcc5c2dSMatthew Dillon * SWAP_PAGER_RESERVE() - reserve swap blocks in object 8504dcc5c2dSMatthew Dillon * 8514dcc5c2dSMatthew Dillon * Assigns swap blocks to the specified range within the object. The 85256ce850bSKonstantin Belousov * swap blocks are not zeroed. Any previous swap assignment is destroyed. 8534dcc5c2dSMatthew Dillon * 8544dcc5c2dSMatthew Dillon * Returns 0 on success, -1 on failure. 8554dcc5c2dSMatthew Dillon */ 8564dcc5c2dSMatthew Dillon int 8574dcc5c2dSMatthew Dillon swap_pager_reserve(vm_object_t object, vm_pindex_t start, vm_size_t size) 8584dcc5c2dSMatthew Dillon { 8594dcc5c2dSMatthew Dillon int n = 0; 8604dcc5c2dSMatthew Dillon daddr_t blk = SWAPBLK_NONE; 8614dcc5c2dSMatthew Dillon vm_pindex_t beg = start; /* save start index */ 8624dcc5c2dSMatthew Dillon 86389f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 8644dcc5c2dSMatthew Dillon while (size) { 8654dcc5c2dSMatthew Dillon if (n == 0) { 8664dcc5c2dSMatthew Dillon n = BLIST_MAX_ALLOC; 8674dcc5c2dSMatthew Dillon while ((blk = swp_pager_getswapspace(n)) == SWAPBLK_NONE) { 8684dcc5c2dSMatthew Dillon n >>= 1; 8694dcc5c2dSMatthew Dillon if (n == 0) { 8704dcc5c2dSMatthew Dillon swp_pager_meta_free(object, beg, start - beg); 87189f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 8724dcc5c2dSMatthew Dillon return (-1); 8734dcc5c2dSMatthew Dillon } 8744dcc5c2dSMatthew Dillon } 8754dcc5c2dSMatthew Dillon } 8764dcc5c2dSMatthew Dillon swp_pager_meta_build(object, start, blk); 8774dcc5c2dSMatthew Dillon --size; 8784dcc5c2dSMatthew Dillon ++start; 8794dcc5c2dSMatthew Dillon ++blk; 8804dcc5c2dSMatthew Dillon --n; 8814dcc5c2dSMatthew Dillon } 8824dcc5c2dSMatthew Dillon swp_pager_meta_free(object, start, n); 88389f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 8844dcc5c2dSMatthew Dillon return (0); 88526f9a767SRodney W. Grimes } 88626f9a767SRodney W. Grimes 8870a47b48bSJohn Dyson /* 8881c7c3c6aSMatthew Dillon * SWAP_PAGER_COPY() - copy blocks from source pager to destination pager 8891c7c3c6aSMatthew Dillon * and destroy the source. 8901c7c3c6aSMatthew Dillon * 8911c7c3c6aSMatthew Dillon * Copy any valid swapblks from the source to the destination. In 8921c7c3c6aSMatthew Dillon * cases where both the source and destination have a valid swapblk, 8931c7c3c6aSMatthew Dillon * we keep the destination's. 8941c7c3c6aSMatthew Dillon * 89515523cf7SKonstantin Belousov * This routine is allowed to sleep. It may sleep allocating metadata 8961c7c3c6aSMatthew Dillon * indirectly through swp_pager_meta_build() or if paging is still in 8971c7c3c6aSMatthew Dillon * progress on the source. 8981c7c3c6aSMatthew Dillon * 8991c7c3c6aSMatthew Dillon * The source object contains no vm_page_t's (which is just as well) 9001c7c3c6aSMatthew Dillon * 9011c7c3c6aSMatthew Dillon * The source object is of type OBJT_SWAP. 9021c7c3c6aSMatthew Dillon * 90315523cf7SKonstantin Belousov * The source and destination objects must be locked. 90415523cf7SKonstantin Belousov * Both object locks may temporarily be released. 90526f9a767SRodney W. Grimes */ 90626f9a767SRodney W. Grimes void 9072f249180SPoul-Henning Kamp swap_pager_copy(vm_object_t srcobject, vm_object_t dstobject, 9082f249180SPoul-Henning Kamp vm_pindex_t offset, int destroysource) 90926f9a767SRodney W. Grimes { 910a316d390SJohn Dyson vm_pindex_t i; 9114dcc5c2dSMatthew Dillon 91289f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(srcobject); 91389f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(dstobject); 9140cddd8f0SMatthew Dillon 91526f9a767SRodney W. Grimes /* 9161c7c3c6aSMatthew Dillon * If destroysource is set, we remove the source object from the 9171c7c3c6aSMatthew Dillon * swap_pager internal queue now. 91826f9a767SRodney W. Grimes */ 919cbd8ec09SJohn Dyson if (destroysource) { 920bd228075SAlan Cox if (srcobject->handle != NULL) { 921a9fa2c05SAlfred Perlstein mtx_lock(&sw_alloc_mtx); 9221c7c3c6aSMatthew Dillon TAILQ_REMOVE( 9231c7c3c6aSMatthew Dillon NOBJLIST(srcobject->handle), 9241c7c3c6aSMatthew Dillon srcobject, 9251c7c3c6aSMatthew Dillon pager_object_list 9261c7c3c6aSMatthew Dillon ); 927a9fa2c05SAlfred Perlstein mtx_unlock(&sw_alloc_mtx); 928cbd8ec09SJohn Dyson } 929bd228075SAlan Cox } 93026f9a767SRodney W. Grimes 9311c7c3c6aSMatthew Dillon /* 9321c7c3c6aSMatthew Dillon * transfer source to destination. 9331c7c3c6aSMatthew Dillon */ 9341c7c3c6aSMatthew Dillon for (i = 0; i < dstobject->size; ++i) { 9351c7c3c6aSMatthew Dillon daddr_t dstaddr; 9361c7c3c6aSMatthew Dillon 9371c7c3c6aSMatthew Dillon /* 9381c7c3c6aSMatthew Dillon * Locate (without changing) the swapblk on the destination, 9391c7c3c6aSMatthew Dillon * unless it is invalid in which case free it silently, or 9401c7c3c6aSMatthew Dillon * if the destination is a resident page, in which case the 9411c7c3c6aSMatthew Dillon * source is thrown away. 9421c7c3c6aSMatthew Dillon */ 9431c7c3c6aSMatthew Dillon dstaddr = swp_pager_meta_ctl(dstobject, i, 0); 9441c7c3c6aSMatthew Dillon 9451c7c3c6aSMatthew Dillon if (dstaddr == SWAPBLK_NONE) { 9461c7c3c6aSMatthew Dillon /* 9471c7c3c6aSMatthew Dillon * Destination has no swapblk and is not resident, 9481c7c3c6aSMatthew Dillon * copy source. 9491c7c3c6aSMatthew Dillon */ 9501c7c3c6aSMatthew Dillon daddr_t srcaddr; 9511c7c3c6aSMatthew Dillon 9521c7c3c6aSMatthew Dillon srcaddr = swp_pager_meta_ctl( 9531c7c3c6aSMatthew Dillon srcobject, 9541c7c3c6aSMatthew Dillon i + offset, 9551c7c3c6aSMatthew Dillon SWM_POP 9561c7c3c6aSMatthew Dillon ); 9571c7c3c6aSMatthew Dillon 958ee3dc7d7SAlan Cox if (srcaddr != SWAPBLK_NONE) { 959c7c8dd7eSAlan Cox /* 960c7c8dd7eSAlan Cox * swp_pager_meta_build() can sleep. 961c7c8dd7eSAlan Cox */ 962c7c8dd7eSAlan Cox vm_object_pip_add(srcobject, 1); 96389f6b863SAttilio Rao VM_OBJECT_WUNLOCK(srcobject); 964c7c8dd7eSAlan Cox vm_object_pip_add(dstobject, 1); 9654dcc5c2dSMatthew Dillon swp_pager_meta_build(dstobject, i, srcaddr); 966c7c8dd7eSAlan Cox vm_object_pip_wakeup(dstobject); 96789f6b863SAttilio Rao VM_OBJECT_WLOCK(srcobject); 968c7c8dd7eSAlan Cox vm_object_pip_wakeup(srcobject); 969ee3dc7d7SAlan Cox } 9701c7c3c6aSMatthew Dillon } else { 9711c7c3c6aSMatthew Dillon /* 9721c7c3c6aSMatthew Dillon * Destination has valid swapblk or it is represented 9731c7c3c6aSMatthew Dillon * by a resident page. We destroy the sourceblock. 9741c7c3c6aSMatthew Dillon */ 9751c7c3c6aSMatthew Dillon 9761c7c3c6aSMatthew Dillon swp_pager_meta_ctl(srcobject, i + offset, SWM_FREE); 9771c7c3c6aSMatthew Dillon } 97826f9a767SRodney W. Grimes } 97926f9a767SRodney W. Grimes 98026f9a767SRodney W. Grimes /* 9811c7c3c6aSMatthew Dillon * Free left over swap blocks in source. 9821c7c3c6aSMatthew Dillon * 9831c7c3c6aSMatthew Dillon * We have to revert the type to OBJT_DEFAULT so we do not accidently 9841c7c3c6aSMatthew Dillon * double-remove the object from the swap queues. 98526f9a767SRodney W. Grimes */ 986c0877f10SJohn Dyson if (destroysource) { 9871c7c3c6aSMatthew Dillon swp_pager_meta_free_all(srcobject); 9881c7c3c6aSMatthew Dillon /* 9891c7c3c6aSMatthew Dillon * Reverting the type is not necessary, the caller is going 9901c7c3c6aSMatthew Dillon * to destroy srcobject directly, but I'm doing it here 991956f3135SPhilippe Charnier * for consistency since we've removed the object from its 9921c7c3c6aSMatthew Dillon * queues. 9931c7c3c6aSMatthew Dillon */ 9941c7c3c6aSMatthew Dillon srcobject->type = OBJT_DEFAULT; 995c0877f10SJohn Dyson } 99626f9a767SRodney W. Grimes } 99726f9a767SRodney W. Grimes 998df8bae1dSRodney W. Grimes /* 9991c7c3c6aSMatthew Dillon * SWAP_PAGER_HASPAGE() - determine if we have good backing store for 10001c7c3c6aSMatthew Dillon * the requested page. 10011c7c3c6aSMatthew Dillon * 10021c7c3c6aSMatthew Dillon * We determine whether good backing store exists for the requested 10031c7c3c6aSMatthew Dillon * page and return TRUE if it does, FALSE if it doesn't. 10041c7c3c6aSMatthew Dillon * 10051c7c3c6aSMatthew Dillon * If TRUE, we also try to determine how much valid, contiguous backing 10061c7c3c6aSMatthew Dillon * store exists before and after the requested page within a reasonable 10071c7c3c6aSMatthew Dillon * distance. We do not try to restrict it to the swap device stripe 10081c7c3c6aSMatthew Dillon * (that is handled in getpages/putpages). It probably isn't worth 10091c7c3c6aSMatthew Dillon * doing here. 1010df8bae1dSRodney W. Grimes */ 10115ea4972cSAlan Cox static boolean_t 10122f249180SPoul-Henning Kamp swap_pager_haspage(vm_object_t object, vm_pindex_t pindex, int *before, int *after) 101326f9a767SRodney W. Grimes { 10141c7c3c6aSMatthew Dillon daddr_t blk0; 101526f9a767SRodney W. Grimes 1016c25673ffSAttilio Rao VM_OBJECT_ASSERT_LOCKED(object); 10171c7c3c6aSMatthew Dillon /* 10181c7c3c6aSMatthew Dillon * do we have good backing store at the requested index ? 10191c7c3c6aSMatthew Dillon */ 10201c7c3c6aSMatthew Dillon blk0 = swp_pager_meta_ctl(object, pindex, 0); 10211c7c3c6aSMatthew Dillon 10224dcc5c2dSMatthew Dillon if (blk0 == SWAPBLK_NONE) { 10231c7c3c6aSMatthew Dillon if (before) 102424a1cce3SDavid Greenman *before = 0; 10251c7c3c6aSMatthew Dillon if (after) 102624a1cce3SDavid Greenman *after = 0; 102726f9a767SRodney W. Grimes return (FALSE); 102826f9a767SRodney W. Grimes } 102926f9a767SRodney W. Grimes 103026f9a767SRodney W. Grimes /* 10311c7c3c6aSMatthew Dillon * find backwards-looking contiguous good backing store 1032e47ed70bSJohn Dyson */ 10331c7c3c6aSMatthew Dillon if (before != NULL) { 103426f9a767SRodney W. Grimes int i; 10350d94caffSDavid Greenman 10361c7c3c6aSMatthew Dillon for (i = 1; i < (SWB_NPAGES/2); ++i) { 10371c7c3c6aSMatthew Dillon daddr_t blk; 10381c7c3c6aSMatthew Dillon 10391c7c3c6aSMatthew Dillon if (i > pindex) 10401c7c3c6aSMatthew Dillon break; 10411c7c3c6aSMatthew Dillon blk = swp_pager_meta_ctl(object, pindex - i, 0); 10421c7c3c6aSMatthew Dillon if (blk != blk0 - i) 10431c7c3c6aSMatthew Dillon break; 1044ffc82b0aSJohn Dyson } 10451c7c3c6aSMatthew Dillon *before = (i - 1); 104626f9a767SRodney W. Grimes } 104726f9a767SRodney W. Grimes 104826f9a767SRodney W. Grimes /* 10491c7c3c6aSMatthew Dillon * find forward-looking contiguous good backing store 105026f9a767SRodney W. Grimes */ 10511c7c3c6aSMatthew Dillon if (after != NULL) { 10521c7c3c6aSMatthew Dillon int i; 10531c7c3c6aSMatthew Dillon 10541c7c3c6aSMatthew Dillon for (i = 1; i < (SWB_NPAGES/2); ++i) { 10551c7c3c6aSMatthew Dillon daddr_t blk; 10561c7c3c6aSMatthew Dillon 10571c7c3c6aSMatthew Dillon blk = swp_pager_meta_ctl(object, pindex + i, 0); 10581c7c3c6aSMatthew Dillon if (blk != blk0 + i) 10591c7c3c6aSMatthew Dillon break; 106026f9a767SRodney W. Grimes } 10611c7c3c6aSMatthew Dillon *after = (i - 1); 10621c7c3c6aSMatthew Dillon } 10631c7c3c6aSMatthew Dillon return (TRUE); 10641c7c3c6aSMatthew Dillon } 10651c7c3c6aSMatthew Dillon 10661c7c3c6aSMatthew Dillon /* 10671c7c3c6aSMatthew Dillon * SWAP_PAGER_PAGE_UNSWAPPED() - remove swap backing store related to page 10681c7c3c6aSMatthew Dillon * 10691c7c3c6aSMatthew Dillon * This removes any associated swap backing store, whether valid or 10701c7c3c6aSMatthew Dillon * not, from the page. 10711c7c3c6aSMatthew Dillon * 10721c7c3c6aSMatthew Dillon * This routine is typically called when a page is made dirty, at 10731c7c3c6aSMatthew Dillon * which point any associated swap can be freed. MADV_FREE also 10741c7c3c6aSMatthew Dillon * calls us in a special-case situation 10751c7c3c6aSMatthew Dillon * 10761c7c3c6aSMatthew Dillon * NOTE!!! If the page is clean and the swap was valid, the caller 10771c7c3c6aSMatthew Dillon * should make the page dirty before calling this routine. This routine 10781c7c3c6aSMatthew Dillon * does NOT change the m->dirty status of the page. Also: MADV_FREE 10791c7c3c6aSMatthew Dillon * depends on it. 10801c7c3c6aSMatthew Dillon * 108115523cf7SKonstantin Belousov * This routine may not sleep. 1082c25673ffSAttilio Rao * 1083c25673ffSAttilio Rao * The object containing the page must be locked. 10841c7c3c6aSMatthew Dillon */ 10851c7c3c6aSMatthew Dillon static void 10862f249180SPoul-Henning Kamp swap_pager_unswapped(vm_page_t m) 10871c7c3c6aSMatthew Dillon { 10882f249180SPoul-Henning Kamp 10891c7c3c6aSMatthew Dillon swp_pager_meta_ctl(m->object, m->pindex, SWM_FREE); 10901c7c3c6aSMatthew Dillon } 10911c7c3c6aSMatthew Dillon 10921c7c3c6aSMatthew Dillon /* 10931c7c3c6aSMatthew Dillon * SWAP_PAGER_GETPAGES() - bring pages in from swap 10941c7c3c6aSMatthew Dillon * 10951c7c3c6aSMatthew Dillon * Attempt to retrieve (m, count) pages from backing store, but make 10961c7c3c6aSMatthew Dillon * sure we retrieve at least m[reqpage]. We try to load in as large 10971c7c3c6aSMatthew Dillon * a chunk surrounding m[reqpage] as is contiguous in swap and which 10981c7c3c6aSMatthew Dillon * belongs to the same object. 10991c7c3c6aSMatthew Dillon * 11001c7c3c6aSMatthew Dillon * The code is designed for asynchronous operation and 11011c7c3c6aSMatthew Dillon * immediate-notification of 'reqpage' but tends not to be 11021c7c3c6aSMatthew Dillon * used that way. Please do not optimize-out this algorithmic 11031c7c3c6aSMatthew Dillon * feature, I intend to improve on it in the future. 11041c7c3c6aSMatthew Dillon * 11051c7c3c6aSMatthew Dillon * The parent has a single vm_object_pip_add() reference prior to 11061c7c3c6aSMatthew Dillon * calling us and we should return with the same. 11071c7c3c6aSMatthew Dillon * 11081c7c3c6aSMatthew Dillon * The parent has BUSY'd the pages. We should return with 'm' 11091c7c3c6aSMatthew Dillon * left busy, but the others adjusted. 11101c7c3c6aSMatthew Dillon */ 1111f708ef1bSPoul-Henning Kamp static int 11122f249180SPoul-Henning Kamp swap_pager_getpages(vm_object_t object, vm_page_t *m, int count, int reqpage) 1113df8bae1dSRodney W. Grimes { 11141c7c3c6aSMatthew Dillon struct buf *bp; 11151c7c3c6aSMatthew Dillon vm_page_t mreq; 111626f9a767SRodney W. Grimes int i; 111726f9a767SRodney W. Grimes int j; 11181c7c3c6aSMatthew Dillon daddr_t blk; 11190d94caffSDavid Greenman 11201c7c3c6aSMatthew Dillon mreq = m[reqpage]; 11211c7c3c6aSMatthew Dillon 1122e04e4bacSPoul-Henning Kamp KASSERT(mreq->object == object, 1123e04e4bacSPoul-Henning Kamp ("swap_pager_getpages: object mismatch %p/%p", 1124e04e4bacSPoul-Henning Kamp object, mreq->object)); 1125e04e4bacSPoul-Henning Kamp 11261c7c3c6aSMatthew Dillon /* 11271c7c3c6aSMatthew Dillon * Calculate range to retrieve. The pages have already been assigned 1128751221fdSPoul-Henning Kamp * their swapblks. We require a *contiguous* range but we know it to 1129751221fdSPoul-Henning Kamp * not span devices. If we do not supply it, bad things 11304dcc5c2dSMatthew Dillon * happen. Note that blk, iblk & jblk can be SWAPBLK_NONE, but the 11314dcc5c2dSMatthew Dillon * loops are set up such that the case(s) are handled implicitly. 11324dcc5c2dSMatthew Dillon * 11330b6ace47SAlan Cox * The swp_*() calls must be made with the object locked. 11341c7c3c6aSMatthew Dillon */ 11351c7c3c6aSMatthew Dillon blk = swp_pager_meta_ctl(mreq->object, mreq->pindex, 0); 11361c7c3c6aSMatthew Dillon 11371c7c3c6aSMatthew Dillon for (i = reqpage - 1; i >= 0; --i) { 11381c7c3c6aSMatthew Dillon daddr_t iblk; 11391c7c3c6aSMatthew Dillon 11401c7c3c6aSMatthew Dillon iblk = swp_pager_meta_ctl(m[i]->object, m[i]->pindex, 0); 11411c7c3c6aSMatthew Dillon if (blk != iblk + (reqpage - i)) 114226f9a767SRodney W. Grimes break; 114326f9a767SRodney W. Grimes } 11441c7c3c6aSMatthew Dillon ++i; 11451c7c3c6aSMatthew Dillon 11461c7c3c6aSMatthew Dillon for (j = reqpage + 1; j < count; ++j) { 11471c7c3c6aSMatthew Dillon daddr_t jblk; 11481c7c3c6aSMatthew Dillon 11491c7c3c6aSMatthew Dillon jblk = swp_pager_meta_ctl(m[j]->object, m[j]->pindex, 0); 11501c7c3c6aSMatthew Dillon if (blk != jblk - (j - reqpage)) 11511c7c3c6aSMatthew Dillon break; 11521c7c3c6aSMatthew Dillon } 11531c7c3c6aSMatthew Dillon 11541c7c3c6aSMatthew Dillon /* 11551c7c3c6aSMatthew Dillon * free pages outside our collection range. Note: we never free 11561c7c3c6aSMatthew Dillon * mreq, it must remain busy throughout. 11571c7c3c6aSMatthew Dillon */ 1158071a1710SAlan Cox if (0 < i || j < count) { 11591c7c3c6aSMatthew Dillon int k; 11601c7c3c6aSMatthew Dillon 11613c4a2440SAlan Cox for (k = 0; k < i; ++k) 1162e86a87e9SKonstantin Belousov swp_pager_free_nrpage(m[k]); 11633c4a2440SAlan Cox for (k = j; k < count; ++k) 11642965a453SKip Macy swp_pager_free_nrpage(m[k]); 1165071a1710SAlan Cox } 11661c7c3c6aSMatthew Dillon 11671c7c3c6aSMatthew Dillon /* 11684dcc5c2dSMatthew Dillon * Return VM_PAGER_FAIL if we have nothing to do. Return mreq 11694dcc5c2dSMatthew Dillon * still busy, but the others unbusied. 11701c7c3c6aSMatthew Dillon */ 11714dcc5c2dSMatthew Dillon if (blk == SWAPBLK_NONE) 117226f9a767SRodney W. Grimes return (VM_PAGER_FAIL); 1173df8bae1dSRodney W. Grimes 117416f62314SDavid Greenman /* 11758630c117SAlan Cox * Getpbuf() can sleep. 11768630c117SAlan Cox */ 117789f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 11788630c117SAlan Cox /* 117916f62314SDavid Greenman * Get a swap buffer header to perform the IO 118016f62314SDavid Greenman */ 11811c7c3c6aSMatthew Dillon bp = getpbuf(&nsw_rcount); 11825e04322aSPoul-Henning Kamp bp->b_flags |= B_PAGING; 118326f9a767SRodney W. Grimes 118421144e3bSPoul-Henning Kamp bp->b_iocmd = BIO_READ; 11851c7c3c6aSMatthew Dillon bp->b_iodone = swp_pager_async_iodone; 1186fdcc1cc0SJohn Baldwin bp->b_rcred = crhold(thread0.td_ucred); 1187fdcc1cc0SJohn Baldwin bp->b_wcred = crhold(thread0.td_ucred); 11881c7c3c6aSMatthew Dillon bp->b_blkno = blk - (reqpage - i); 11891c7c3c6aSMatthew Dillon bp->b_bcount = PAGE_SIZE * (j - i); 11901c7c3c6aSMatthew Dillon bp->b_bufsize = PAGE_SIZE * (j - i); 11911c7c3c6aSMatthew Dillon bp->b_pager.pg_reqpage = reqpage - i; 11921c7c3c6aSMatthew Dillon 119389f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 11941c7c3c6aSMatthew Dillon { 11951c7c3c6aSMatthew Dillon int k; 11961c7c3c6aSMatthew Dillon 11971c7c3c6aSMatthew Dillon for (k = i; k < j; ++k) { 11981c7c3c6aSMatthew Dillon bp->b_pages[k - i] = m[k]; 11995786be7cSAlan Cox m[k]->oflags |= VPO_SWAPINPROG; 12001c7c3c6aSMatthew Dillon } 12011c7c3c6aSMatthew Dillon } 12021c7c3c6aSMatthew Dillon bp->b_npages = j - i; 120326f9a767SRodney W. Grimes 1204b4b70819SAttilio Rao PCPU_INC(cnt.v_swapin); 1205b4b70819SAttilio Rao PCPU_ADD(cnt.v_swappgsin, bp->b_npages); 12061c7c3c6aSMatthew Dillon 1207df8bae1dSRodney W. Grimes /* 12081c7c3c6aSMatthew Dillon * We still hold the lock on mreq, and our automatic completion routine 12091c7c3c6aSMatthew Dillon * does not remove it. 1210df8bae1dSRodney W. Grimes */ 1211071a1710SAlan Cox vm_object_pip_add(object, bp->b_npages); 121289f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 12131c7c3c6aSMatthew Dillon 12141c7c3c6aSMatthew Dillon /* 12151c7c3c6aSMatthew Dillon * perform the I/O. NOTE!!! bp cannot be considered valid after 12161c7c3c6aSMatthew Dillon * this point because we automatically release it on completion. 12171c7c3c6aSMatthew Dillon * Instead, we look at the one page we are interested in which we 12181c7c3c6aSMatthew Dillon * still hold a lock on even through the I/O completion. 12191c7c3c6aSMatthew Dillon * 12201c7c3c6aSMatthew Dillon * The other pages in our m[] array are also released on completion, 12211c7c3c6aSMatthew Dillon * so we cannot assume they are valid anymore either. 12221c7c3c6aSMatthew Dillon * 1223c37a77eeSPoul-Henning Kamp * NOTE: b_blkno is destroyed by the call to swapdev_strategy 12241c7c3c6aSMatthew Dillon */ 1225b890cb2cSPeter Wemm BUF_KERNPROC(bp); 12264b03903aSPoul-Henning Kamp swp_pager_strategy(bp); 122726f9a767SRodney W. Grimes 122826f9a767SRodney W. Grimes /* 12295786be7cSAlan Cox * wait for the page we want to complete. VPO_SWAPINPROG is always 12301c7c3c6aSMatthew Dillon * cleared on completion. If an I/O error occurs, SWAPBLK_NONE 12311c7c3c6aSMatthew Dillon * is set in the meta-data. 123226f9a767SRodney W. Grimes */ 123389f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 12345786be7cSAlan Cox while ((mreq->oflags & VPO_SWAPINPROG) != 0) { 1235c7aebda8SAttilio Rao mreq->oflags |= VPO_SWAPSLEEP; 1236b4b70819SAttilio Rao PCPU_INC(cnt.v_intrans); 1237c7aebda8SAttilio Rao if (VM_OBJECT_SLEEP(object, &object->paging_in_progress, PSWP, 1238c7aebda8SAttilio Rao "swread", hz * 20)) { 12399bd86a98SBruce M Simpson printf( 1240c5690651SPoul-Henning Kamp "swap_pager: indefinite wait buffer: bufobj: %p, blkno: %jd, size: %ld\n", 1241c5690651SPoul-Henning Kamp bp->b_bufobj, (intmax_t)bp->b_blkno, bp->b_bcount); 12421c7c3c6aSMatthew Dillon } 12431b119d9dSDavid Greenman } 124426f9a767SRodney W. Grimes 124526f9a767SRodney W. Grimes /* 1246a1287949SEivind Eklund * mreq is left busied after completion, but all the other pages 12471c7c3c6aSMatthew Dillon * are freed. If we had an unrecoverable read error the page will 12481c7c3c6aSMatthew Dillon * not be valid. 124926f9a767SRodney W. Grimes */ 12501c7c3c6aSMatthew Dillon if (mreq->valid != VM_PAGE_BITS_ALL) { 12511c7c3c6aSMatthew Dillon return (VM_PAGER_ERROR); 125226f9a767SRodney W. Grimes } else { 12531c7c3c6aSMatthew Dillon return (VM_PAGER_OK); 125426f9a767SRodney W. Grimes } 12551c7c3c6aSMatthew Dillon 12561c7c3c6aSMatthew Dillon /* 12571c7c3c6aSMatthew Dillon * A final note: in a low swap situation, we cannot deallocate swap 12581c7c3c6aSMatthew Dillon * and mark a page dirty here because the caller is likely to mark 12591c7c3c6aSMatthew Dillon * the page clean when we return, causing the page to possibly revert 12601c7c3c6aSMatthew Dillon * to all-zero's later. 12611c7c3c6aSMatthew Dillon */ 1262df8bae1dSRodney W. Grimes } 1263df8bae1dSRodney W. Grimes 12641c7c3c6aSMatthew Dillon /* 126590effb23SGleb Smirnoff * swap_pager_getpages_async(): 126690effb23SGleb Smirnoff * 126790effb23SGleb Smirnoff * Right now this is emulation of asynchronous operation on top of 126890effb23SGleb Smirnoff * swap_pager_getpages(). 126990effb23SGleb Smirnoff */ 127090effb23SGleb Smirnoff static int 127190effb23SGleb Smirnoff swap_pager_getpages_async(vm_object_t object, vm_page_t *m, int count, 127290effb23SGleb Smirnoff int reqpage, pgo_getpages_iodone_t iodone, void *arg) 127390effb23SGleb Smirnoff { 127490effb23SGleb Smirnoff int r, error; 127590effb23SGleb Smirnoff 127690effb23SGleb Smirnoff r = swap_pager_getpages(object, m, count, reqpage); 127790effb23SGleb Smirnoff VM_OBJECT_WUNLOCK(object); 127890effb23SGleb Smirnoff switch (r) { 127990effb23SGleb Smirnoff case VM_PAGER_OK: 128090effb23SGleb Smirnoff error = 0; 128190effb23SGleb Smirnoff break; 128290effb23SGleb Smirnoff case VM_PAGER_ERROR: 128390effb23SGleb Smirnoff error = EIO; 128490effb23SGleb Smirnoff break; 128590effb23SGleb Smirnoff case VM_PAGER_FAIL: 128690effb23SGleb Smirnoff error = EINVAL; 128790effb23SGleb Smirnoff break; 128890effb23SGleb Smirnoff default: 1289d9328101SGleb Smirnoff panic("unhandled swap_pager_getpages() error %d", r); 129090effb23SGleb Smirnoff } 129190effb23SGleb Smirnoff (iodone)(arg, m, count, error); 129290effb23SGleb Smirnoff VM_OBJECT_WLOCK(object); 129390effb23SGleb Smirnoff 129490effb23SGleb Smirnoff return (r); 129590effb23SGleb Smirnoff } 129690effb23SGleb Smirnoff 129790effb23SGleb Smirnoff /* 12981c7c3c6aSMatthew Dillon * swap_pager_putpages: 12991c7c3c6aSMatthew Dillon * 13001c7c3c6aSMatthew Dillon * Assign swap (if necessary) and initiate I/O on the specified pages. 13011c7c3c6aSMatthew Dillon * 13021c7c3c6aSMatthew Dillon * We support both OBJT_DEFAULT and OBJT_SWAP objects. DEFAULT objects 13031c7c3c6aSMatthew Dillon * are automatically converted to SWAP objects. 13041c7c3c6aSMatthew Dillon * 1305ea3aecf5SPeter Wemm * In a low memory situation we may block in VOP_STRATEGY(), but the new 13061c7c3c6aSMatthew Dillon * vm_page reservation system coupled with properly written VFS devices 13071c7c3c6aSMatthew Dillon * should ensure that no low-memory deadlock occurs. This is an area 13081c7c3c6aSMatthew Dillon * which needs work. 13091c7c3c6aSMatthew Dillon * 13101c7c3c6aSMatthew Dillon * The parent has N vm_object_pip_add() references prior to 13111c7c3c6aSMatthew Dillon * calling us and will remove references for rtvals[] that are 13121c7c3c6aSMatthew Dillon * not set to VM_PAGER_PEND. We need to remove the rest on I/O 13131c7c3c6aSMatthew Dillon * completion. 13141c7c3c6aSMatthew Dillon * 13151c7c3c6aSMatthew Dillon * The parent has soft-busy'd the pages it passes us and will unbusy 13161c7c3c6aSMatthew Dillon * those whos rtvals[] entry is not set to VM_PAGER_PEND on return. 13171c7c3c6aSMatthew Dillon * We need to unbusy the rest on I/O completion. 13181c7c3c6aSMatthew Dillon */ 1319e4542174SMatthew Dillon void 13202f249180SPoul-Henning Kamp swap_pager_putpages(vm_object_t object, vm_page_t *m, int count, 1321e065e87cSKonstantin Belousov int flags, int *rtvals) 1322df8bae1dSRodney W. Grimes { 1323e065e87cSKonstantin Belousov int i, n; 1324e065e87cSKonstantin Belousov boolean_t sync; 1325df8bae1dSRodney W. Grimes 13261c7c3c6aSMatthew Dillon if (count && m[0]->object != object) { 13277036145bSMaxim Konovalov panic("swap_pager_putpages: object mismatch %p/%p", 13281c7c3c6aSMatthew Dillon object, 13291c7c3c6aSMatthew Dillon m[0]->object 13301c7c3c6aSMatthew Dillon ); 13311c7c3c6aSMatthew Dillon } 1332ee3dc7d7SAlan Cox 13331c7c3c6aSMatthew Dillon /* 13341c7c3c6aSMatthew Dillon * Step 1 13351c7c3c6aSMatthew Dillon * 13361c7c3c6aSMatthew Dillon * Turn object into OBJT_SWAP 13371c7c3c6aSMatthew Dillon * check for bogus sysops 13381c7c3c6aSMatthew Dillon * force sync if not pageout process 13391c7c3c6aSMatthew Dillon */ 13404dcc5c2dSMatthew Dillon if (object->type != OBJT_SWAP) 13414dcc5c2dSMatthew Dillon swp_pager_meta_build(object, 0, SWAPBLK_NONE); 134289f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 1343e47ed70bSJohn Dyson 1344e065e87cSKonstantin Belousov n = 0; 1345e47ed70bSJohn Dyson if (curproc != pageproc) 1346e47ed70bSJohn Dyson sync = TRUE; 1347e065e87cSKonstantin Belousov else 1348e065e87cSKonstantin Belousov sync = (flags & VM_PAGER_PUT_SYNC) != 0; 134926f9a767SRodney W. Grimes 13501c7c3c6aSMatthew Dillon /* 13511c7c3c6aSMatthew Dillon * Step 2 13521c7c3c6aSMatthew Dillon * 1353ad3cce20SMatthew Dillon * Update nsw parameters from swap_async_max sysctl values. 1354ad3cce20SMatthew Dillon * Do not let the sysop crash the machine with bogus numbers. 1355327f4e83SMatthew Dillon */ 13566d541bf1SJohn Baldwin mtx_lock(&pbuf_mtx); 1357327f4e83SMatthew Dillon if (swap_async_max != nsw_wcount_async_max) { 1358327f4e83SMatthew Dillon int n; 1359327f4e83SMatthew Dillon 1360327f4e83SMatthew Dillon /* 1361327f4e83SMatthew Dillon * limit range 1362327f4e83SMatthew Dillon */ 1363327f4e83SMatthew Dillon if ((n = swap_async_max) > nswbuf / 2) 1364327f4e83SMatthew Dillon n = nswbuf / 2; 1365327f4e83SMatthew Dillon if (n < 1) 1366327f4e83SMatthew Dillon n = 1; 1367327f4e83SMatthew Dillon swap_async_max = n; 1368327f4e83SMatthew Dillon 1369327f4e83SMatthew Dillon /* 1370327f4e83SMatthew Dillon * Adjust difference ( if possible ). If the current async 1371327f4e83SMatthew Dillon * count is too low, we may not be able to make the adjustment 1372327f4e83SMatthew Dillon * at this time. 1373327f4e83SMatthew Dillon */ 1374327f4e83SMatthew Dillon n -= nsw_wcount_async_max; 1375327f4e83SMatthew Dillon if (nsw_wcount_async + n >= 0) { 1376327f4e83SMatthew Dillon nsw_wcount_async += n; 1377327f4e83SMatthew Dillon nsw_wcount_async_max += n; 1378327f4e83SMatthew Dillon wakeup(&nsw_wcount_async); 1379327f4e83SMatthew Dillon } 1380327f4e83SMatthew Dillon } 13816d541bf1SJohn Baldwin mtx_unlock(&pbuf_mtx); 1382327f4e83SMatthew Dillon 1383327f4e83SMatthew Dillon /* 1384327f4e83SMatthew Dillon * Step 3 1385327f4e83SMatthew Dillon * 13861c7c3c6aSMatthew Dillon * Assign swap blocks and issue I/O. We reallocate swap on the fly. 13871c7c3c6aSMatthew Dillon * The page is left dirty until the pageout operation completes 13881c7c3c6aSMatthew Dillon * successfully. 13891c7c3c6aSMatthew Dillon */ 13901c7c3c6aSMatthew Dillon for (i = 0; i < count; i += n) { 13911c7c3c6aSMatthew Dillon int j; 13921c7c3c6aSMatthew Dillon struct buf *bp; 1393a316d390SJohn Dyson daddr_t blk; 139426f9a767SRodney W. Grimes 1395df8bae1dSRodney W. Grimes /* 13961c7c3c6aSMatthew Dillon * Maximum I/O size is limited by a number of factors. 1397df8bae1dSRodney W. Grimes */ 13981c7c3c6aSMatthew Dillon n = min(BLIST_MAX_ALLOC, count - i); 1399327f4e83SMatthew Dillon n = min(n, nsw_cluster_max); 14001c7c3c6aSMatthew Dillon 140126f9a767SRodney W. Grimes /* 14021c7c3c6aSMatthew Dillon * Get biggest block of swap we can. If we fail, fall 14031c7c3c6aSMatthew Dillon * back and try to allocate a smaller block. Don't go 14041c7c3c6aSMatthew Dillon * overboard trying to allocate space if it would overly 14051c7c3c6aSMatthew Dillon * fragment swap. 140626f9a767SRodney W. Grimes */ 14071c7c3c6aSMatthew Dillon while ( 14081c7c3c6aSMatthew Dillon (blk = swp_pager_getswapspace(n)) == SWAPBLK_NONE && 14091c7c3c6aSMatthew Dillon n > 4 14101c7c3c6aSMatthew Dillon ) { 14111c7c3c6aSMatthew Dillon n >>= 1; 141226f9a767SRodney W. Grimes } 14131c7c3c6aSMatthew Dillon if (blk == SWAPBLK_NONE) { 14144dcc5c2dSMatthew Dillon for (j = 0; j < n; ++j) 14151c7c3c6aSMatthew Dillon rtvals[i+j] = VM_PAGER_FAIL; 14161c7c3c6aSMatthew Dillon continue; 141726f9a767SRodney W. Grimes } 141826f9a767SRodney W. Grimes 141926f9a767SRodney W. Grimes /* 14201c7c3c6aSMatthew Dillon * All I/O parameters have been satisfied, build the I/O 14211c7c3c6aSMatthew Dillon * request and assign the swap space. 142226f9a767SRodney W. Grimes */ 1423327f4e83SMatthew Dillon if (sync == TRUE) { 1424327f4e83SMatthew Dillon bp = getpbuf(&nsw_wcount_sync); 1425327f4e83SMatthew Dillon } else { 1426327f4e83SMatthew Dillon bp = getpbuf(&nsw_wcount_async); 142721144e3bSPoul-Henning Kamp bp->b_flags = B_ASYNC; 1428327f4e83SMatthew Dillon } 14295e04322aSPoul-Henning Kamp bp->b_flags |= B_PAGING; 1430912e4ae9SPoul-Henning Kamp bp->b_iocmd = BIO_WRITE; 143126f9a767SRodney W. Grimes 1432fdcc1cc0SJohn Baldwin bp->b_rcred = crhold(thread0.td_ucred); 1433fdcc1cc0SJohn Baldwin bp->b_wcred = crhold(thread0.td_ucred); 14341c7c3c6aSMatthew Dillon bp->b_bcount = PAGE_SIZE * n; 14351c7c3c6aSMatthew Dillon bp->b_bufsize = PAGE_SIZE * n; 14361c7c3c6aSMatthew Dillon bp->b_blkno = blk; 1437e47ed70bSJohn Dyson 143889f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 14391c7c3c6aSMatthew Dillon for (j = 0; j < n; ++j) { 14401c7c3c6aSMatthew Dillon vm_page_t mreq = m[i+j]; 14411c7c3c6aSMatthew Dillon 14421c7c3c6aSMatthew Dillon swp_pager_meta_build( 14431c7c3c6aSMatthew Dillon mreq->object, 14441c7c3c6aSMatthew Dillon mreq->pindex, 14454dcc5c2dSMatthew Dillon blk + j 14461c7c3c6aSMatthew Dillon ); 14477dbf82dcSMatthew Dillon vm_page_dirty(mreq); 14481c7c3c6aSMatthew Dillon rtvals[i+j] = VM_PAGER_OK; 14491c7c3c6aSMatthew Dillon 14505786be7cSAlan Cox mreq->oflags |= VPO_SWAPINPROG; 14511c7c3c6aSMatthew Dillon bp->b_pages[j] = mreq; 14521c7c3c6aSMatthew Dillon } 145389f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 14541c7c3c6aSMatthew Dillon bp->b_npages = n; 1455a5296b05SJulian Elischer /* 1456a5296b05SJulian Elischer * Must set dirty range for NFS to work. 1457a5296b05SJulian Elischer */ 1458a5296b05SJulian Elischer bp->b_dirtyoff = 0; 1459a5296b05SJulian Elischer bp->b_dirtyend = bp->b_bcount; 14601c7c3c6aSMatthew Dillon 1461b4b70819SAttilio Rao PCPU_INC(cnt.v_swapout); 1462b4b70819SAttilio Rao PCPU_ADD(cnt.v_swappgsout, bp->b_npages); 146326f9a767SRodney W. Grimes 146426f9a767SRodney W. Grimes /* 14651c7c3c6aSMatthew Dillon * asynchronous 14661c7c3c6aSMatthew Dillon * 1467c37a77eeSPoul-Henning Kamp * NOTE: b_blkno is destroyed by the call to swapdev_strategy 146826f9a767SRodney W. Grimes */ 14691c7c3c6aSMatthew Dillon if (sync == FALSE) { 14701c7c3c6aSMatthew Dillon bp->b_iodone = swp_pager_async_iodone; 147167812eacSKirk McKusick BUF_KERNPROC(bp); 14724b03903aSPoul-Henning Kamp swp_pager_strategy(bp); 14731c7c3c6aSMatthew Dillon 14741c7c3c6aSMatthew Dillon for (j = 0; j < n; ++j) 14751c7c3c6aSMatthew Dillon rtvals[i+j] = VM_PAGER_PEND; 147623955314SAlfred Perlstein /* restart outter loop */ 14771c7c3c6aSMatthew Dillon continue; 147826f9a767SRodney W. Grimes } 1479e47ed70bSJohn Dyson 148026f9a767SRodney W. Grimes /* 14811c7c3c6aSMatthew Dillon * synchronous 14821c7c3c6aSMatthew Dillon * 1483c37a77eeSPoul-Henning Kamp * NOTE: b_blkno is destroyed by the call to swapdev_strategy 14841c7c3c6aSMatthew Dillon */ 14852c840b1fSAlan Cox bp->b_iodone = bdone; 14864b03903aSPoul-Henning Kamp swp_pager_strategy(bp); 14871c7c3c6aSMatthew Dillon 14881c7c3c6aSMatthew Dillon /* 14891c7c3c6aSMatthew Dillon * Wait for the sync I/O to complete, then update rtvals. 14901c7c3c6aSMatthew Dillon * We just set the rtvals[] to VM_PAGER_PEND so we can call 14911c7c3c6aSMatthew Dillon * our async completion routine at the end, thus avoiding a 14921c7c3c6aSMatthew Dillon * double-free. 149326f9a767SRodney W. Grimes */ 14942c840b1fSAlan Cox bwait(bp, PVM, "swwrt"); 14951c7c3c6aSMatthew Dillon for (j = 0; j < n; ++j) 14961c7c3c6aSMatthew Dillon rtvals[i+j] = VM_PAGER_PEND; 14971c7c3c6aSMatthew Dillon /* 14981c7c3c6aSMatthew Dillon * Now that we are through with the bp, we can call the 14991c7c3c6aSMatthew Dillon * normal async completion, which frees everything up. 15001c7c3c6aSMatthew Dillon */ 15011c7c3c6aSMatthew Dillon swp_pager_async_iodone(bp); 15021c7c3c6aSMatthew Dillon } 150389f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 15041c7c3c6aSMatthew Dillon } 15051c7c3c6aSMatthew Dillon 15061c7c3c6aSMatthew Dillon /* 15071c7c3c6aSMatthew Dillon * swp_pager_async_iodone: 15081c7c3c6aSMatthew Dillon * 15091c7c3c6aSMatthew Dillon * Completion routine for asynchronous reads and writes from/to swap. 15101c7c3c6aSMatthew Dillon * Also called manually by synchronous code to finish up a bp. 15111c7c3c6aSMatthew Dillon * 151215523cf7SKonstantin Belousov * This routine may not sleep. 15131c7c3c6aSMatthew Dillon */ 15141c7c3c6aSMatthew Dillon static void 15152f249180SPoul-Henning Kamp swp_pager_async_iodone(struct buf *bp) 15161c7c3c6aSMatthew Dillon { 15171c7c3c6aSMatthew Dillon int i; 15181c7c3c6aSMatthew Dillon vm_object_t object = NULL; 15191c7c3c6aSMatthew Dillon 15201c7c3c6aSMatthew Dillon /* 15211c7c3c6aSMatthew Dillon * report error 15221c7c3c6aSMatthew Dillon */ 1523c244d2deSPoul-Henning Kamp if (bp->b_ioflags & BIO_ERROR) { 15241c7c3c6aSMatthew Dillon printf( 15251c7c3c6aSMatthew Dillon "swap_pager: I/O error - %s failed; blkno %ld," 15261c7c3c6aSMatthew Dillon "size %ld, error %d\n", 152721144e3bSPoul-Henning Kamp ((bp->b_iocmd == BIO_READ) ? "pagein" : "pageout"), 15281c7c3c6aSMatthew Dillon (long)bp->b_blkno, 15291c7c3c6aSMatthew Dillon (long)bp->b_bcount, 15301c7c3c6aSMatthew Dillon bp->b_error 15311c7c3c6aSMatthew Dillon ); 15321c7c3c6aSMatthew Dillon } 15331c7c3c6aSMatthew Dillon 15341c7c3c6aSMatthew Dillon /* 153526f9a767SRodney W. Grimes * remove the mapping for kernel virtual 153626f9a767SRodney W. Grimes */ 15372cc718a1SKonstantin Belousov if ((bp->b_flags & B_UNMAPPED) != 0) { 15382cc718a1SKonstantin Belousov bp->b_data = bp->b_kvaalloc; 15392cc718a1SKonstantin Belousov bp->b_kvabase = bp->b_kvaalloc; 15402cc718a1SKonstantin Belousov bp->b_flags &= ~B_UNMAPPED; 15412cc718a1SKonstantin Belousov } else 15421c7c3c6aSMatthew Dillon pmap_qremove((vm_offset_t)bp->b_data, bp->b_npages); 154326f9a767SRodney W. Grimes 154433a609ecSAlan Cox if (bp->b_npages) { 154533a609ecSAlan Cox object = bp->b_pages[0]->object; 154689f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 154733a609ecSAlan Cox } 15482965a453SKip Macy 154926f9a767SRodney W. Grimes /* 15501c7c3c6aSMatthew Dillon * cleanup pages. If an error occurs writing to swap, we are in 15511c7c3c6aSMatthew Dillon * very serious trouble. If it happens to be a disk error, though, 15521c7c3c6aSMatthew Dillon * we may be able to recover by reassigning the swap later on. So 15531c7c3c6aSMatthew Dillon * in this case we remove the m->swapblk assignment for the page 15541c7c3c6aSMatthew Dillon * but do not free it in the rlist. The errornous block(s) are thus 15551c7c3c6aSMatthew Dillon * never reallocated as swap. Redirty the page and continue. 155626f9a767SRodney W. Grimes */ 15571c7c3c6aSMatthew Dillon for (i = 0; i < bp->b_npages; ++i) { 15581c7c3c6aSMatthew Dillon vm_page_t m = bp->b_pages[i]; 1559e47ed70bSJohn Dyson 15605786be7cSAlan Cox m->oflags &= ~VPO_SWAPINPROG; 1561c7aebda8SAttilio Rao if (m->oflags & VPO_SWAPSLEEP) { 1562c7aebda8SAttilio Rao m->oflags &= ~VPO_SWAPSLEEP; 1563c7aebda8SAttilio Rao wakeup(&object->paging_in_progress); 1564c7aebda8SAttilio Rao } 1565e47ed70bSJohn Dyson 1566c244d2deSPoul-Henning Kamp if (bp->b_ioflags & BIO_ERROR) { 1567ffc82b0aSJohn Dyson /* 15681c7c3c6aSMatthew Dillon * If an error occurs I'd love to throw the swapblk 15691c7c3c6aSMatthew Dillon * away without freeing it back to swapspace, so it 15701c7c3c6aSMatthew Dillon * can never be used again. But I can't from an 15711c7c3c6aSMatthew Dillon * interrupt. 1572ffc82b0aSJohn Dyson */ 157321144e3bSPoul-Henning Kamp if (bp->b_iocmd == BIO_READ) { 15741c7c3c6aSMatthew Dillon /* 15751c7c3c6aSMatthew Dillon * When reading, reqpage needs to stay 15761c7c3c6aSMatthew Dillon * locked for the parent, but all other 15771c7c3c6aSMatthew Dillon * pages can be freed. We still want to 15781c7c3c6aSMatthew Dillon * wakeup the parent waiting on the page, 15791c7c3c6aSMatthew Dillon * though. ( also: pg_reqpage can be -1 and 15801c7c3c6aSMatthew Dillon * not match anything ). 15811c7c3c6aSMatthew Dillon * 15821c7c3c6aSMatthew Dillon * We have to wake specifically requested pages 15835786be7cSAlan Cox * up too because we cleared VPO_SWAPINPROG and 15841c7c3c6aSMatthew Dillon * someone may be waiting for that. 15851c7c3c6aSMatthew Dillon * 15861c7c3c6aSMatthew Dillon * NOTE: for reads, m->dirty will probably 1587956f3135SPhilippe Charnier * be overridden by the original caller of 15881c7c3c6aSMatthew Dillon * getpages so don't play cute tricks here. 15891c7c3c6aSMatthew Dillon */ 15901c7c3c6aSMatthew Dillon m->valid = 0; 15911c7c3c6aSMatthew Dillon if (i != bp->b_pager.pg_reqpage) 1592e86a87e9SKonstantin Belousov swp_pager_free_nrpage(m); 1593c7aebda8SAttilio Rao else { 1594c7aebda8SAttilio Rao vm_page_lock(m); 15951c7c3c6aSMatthew Dillon vm_page_flash(m); 1596c7aebda8SAttilio Rao vm_page_unlock(m); 1597c7aebda8SAttilio Rao } 15981c7c3c6aSMatthew Dillon /* 15991c7c3c6aSMatthew Dillon * If i == bp->b_pager.pg_reqpage, do not wake 16001c7c3c6aSMatthew Dillon * the page up. The caller needs to. 16011c7c3c6aSMatthew Dillon */ 16021c7c3c6aSMatthew Dillon } else { 16031c7c3c6aSMatthew Dillon /* 16041c7c3c6aSMatthew Dillon * If a write error occurs, reactivate page 16051c7c3c6aSMatthew Dillon * so it doesn't clog the inactive list, 16061c7c3c6aSMatthew Dillon * then finish the I/O. 16071c7c3c6aSMatthew Dillon */ 16087dbf82dcSMatthew Dillon vm_page_dirty(m); 16093c4a2440SAlan Cox vm_page_lock(m); 16101c7c3c6aSMatthew Dillon vm_page_activate(m); 16113c4a2440SAlan Cox vm_page_unlock(m); 1612c7aebda8SAttilio Rao vm_page_sunbusy(m); 16131c7c3c6aSMatthew Dillon } 161421144e3bSPoul-Henning Kamp } else if (bp->b_iocmd == BIO_READ) { 16151c7c3c6aSMatthew Dillon /* 16161c7c3c6aSMatthew Dillon * NOTE: for reads, m->dirty will probably be 1617956f3135SPhilippe Charnier * overridden by the original caller of getpages so 16181c7c3c6aSMatthew Dillon * we cannot set them in order to free the underlying 16191c7c3c6aSMatthew Dillon * swap in a low-swap situation. I don't think we'd 16201c7c3c6aSMatthew Dillon * want to do that anyway, but it was an optimization 16211c7c3c6aSMatthew Dillon * that existed in the old swapper for a time before 16221c7c3c6aSMatthew Dillon * it got ripped out due to precisely this problem. 16231c7c3c6aSMatthew Dillon * 16241c7c3c6aSMatthew Dillon * If not the requested page then deactivate it. 16251c7c3c6aSMatthew Dillon * 16261c7c3c6aSMatthew Dillon * Note that the requested page, reqpage, is left 16271c7c3c6aSMatthew Dillon * busied, but we still have to wake it up. The 16281c7c3c6aSMatthew Dillon * other pages are released (unbusied) by 1629c7aebda8SAttilio Rao * vm_page_xunbusy(). 16301c7c3c6aSMatthew Dillon */ 1631016a3c93SAlan Cox KASSERT(!pmap_page_is_mapped(m), 1632016a3c93SAlan Cox ("swp_pager_async_iodone: page %p is mapped", m)); 16331c7c3c6aSMatthew Dillon m->valid = VM_PAGE_BITS_ALL; 1634016a3c93SAlan Cox KASSERT(m->dirty == 0, 1635016a3c93SAlan Cox ("swp_pager_async_iodone: page %p is dirty", m)); 16361c7c3c6aSMatthew Dillon 16371c7c3c6aSMatthew Dillon /* 16381c7c3c6aSMatthew Dillon * We have to wake specifically requested pages 16395786be7cSAlan Cox * up too because we cleared VPO_SWAPINPROG and 16401c7c3c6aSMatthew Dillon * could be waiting for it in getpages. However, 16411c7c3c6aSMatthew Dillon * be sure to not unbusy getpages specifically 16421c7c3c6aSMatthew Dillon * requested page - getpages expects it to be 16431c7c3c6aSMatthew Dillon * left busy. 16441c7c3c6aSMatthew Dillon */ 16451c7c3c6aSMatthew Dillon if (i != bp->b_pager.pg_reqpage) { 16463c4a2440SAlan Cox vm_page_lock(m); 16471c7c3c6aSMatthew Dillon vm_page_deactivate(m); 16483c4a2440SAlan Cox vm_page_unlock(m); 1649c7aebda8SAttilio Rao vm_page_xunbusy(m); 1650c7aebda8SAttilio Rao } else { 1651c7aebda8SAttilio Rao vm_page_lock(m); 16521c7c3c6aSMatthew Dillon vm_page_flash(m); 1653c7aebda8SAttilio Rao vm_page_unlock(m); 1654c7aebda8SAttilio Rao } 16551c7c3c6aSMatthew Dillon } else { 16561c7c3c6aSMatthew Dillon /* 1657016a3c93SAlan Cox * For write success, clear the dirty 16581c7c3c6aSMatthew Dillon * status, then finish the I/O ( which decrements the 16591c7c3c6aSMatthew Dillon * busy count and possibly wakes waiter's up ). 16601c7c3c6aSMatthew Dillon */ 16616031c68dSAlan Cox KASSERT(!pmap_page_is_write_mapped(m), 1662016a3c93SAlan Cox ("swp_pager_async_iodone: page %p is not write" 1663016a3c93SAlan Cox " protected", m)); 1664c52e7044SAlan Cox vm_page_undirty(m); 1665c7aebda8SAttilio Rao vm_page_sunbusy(m); 16663c4a2440SAlan Cox if (vm_page_count_severe()) { 16673c4a2440SAlan Cox vm_page_lock(m); 16682c840b1fSAlan Cox vm_page_try_to_cache(m); 16692965a453SKip Macy vm_page_unlock(m); 16702965a453SKip Macy } 16713c4a2440SAlan Cox } 16723c4a2440SAlan Cox } 167326f9a767SRodney W. Grimes 16741c7c3c6aSMatthew Dillon /* 16751c7c3c6aSMatthew Dillon * adjust pip. NOTE: the original parent may still have its own 16761c7c3c6aSMatthew Dillon * pip refs on the object. 16771c7c3c6aSMatthew Dillon */ 16780d420ad3SAlan Cox if (object != NULL) { 16791c7c3c6aSMatthew Dillon vm_object_pip_wakeupn(object, bp->b_npages); 168089f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 16810d420ad3SAlan Cox } 168226f9a767SRodney W. Grimes 16831c7c3c6aSMatthew Dillon /* 1684100650deSOlivier Houchard * swapdev_strategy() manually sets b_vp and b_bufobj before calling 1685100650deSOlivier Houchard * bstrategy(). Set them back to NULL now we're done with it, or we'll 1686100650deSOlivier Houchard * trigger a KASSERT in relpbuf(). 1687100650deSOlivier Houchard */ 1688100650deSOlivier Houchard if (bp->b_vp) { 1689100650deSOlivier Houchard bp->b_vp = NULL; 1690100650deSOlivier Houchard bp->b_bufobj = NULL; 1691100650deSOlivier Houchard } 1692100650deSOlivier Houchard /* 16931c7c3c6aSMatthew Dillon * release the physical I/O buffer 16941c7c3c6aSMatthew Dillon */ 1695327f4e83SMatthew Dillon relpbuf( 1696327f4e83SMatthew Dillon bp, 169721144e3bSPoul-Henning Kamp ((bp->b_iocmd == BIO_READ) ? &nsw_rcount : 1698327f4e83SMatthew Dillon ((bp->b_flags & B_ASYNC) ? 1699327f4e83SMatthew Dillon &nsw_wcount_async : 1700327f4e83SMatthew Dillon &nsw_wcount_sync 1701327f4e83SMatthew Dillon ) 1702327f4e83SMatthew Dillon ) 1703327f4e83SMatthew Dillon ); 170426f9a767SRodney W. Grimes } 17051c7c3c6aSMatthew Dillon 170692da00bbSMatthew Dillon /* 170792da00bbSMatthew Dillon * swap_pager_isswapped: 170892da00bbSMatthew Dillon * 170992da00bbSMatthew Dillon * Return 1 if at least one page in the given object is paged 171092da00bbSMatthew Dillon * out to the given swap device. 171192da00bbSMatthew Dillon * 171215523cf7SKonstantin Belousov * This routine may not sleep. 171392da00bbSMatthew Dillon */ 17148f60c087SPoul-Henning Kamp int 17158f60c087SPoul-Henning Kamp swap_pager_isswapped(vm_object_t object, struct swdevt *sp) 17168f60c087SPoul-Henning Kamp { 171792da00bbSMatthew Dillon daddr_t index = 0; 171892da00bbSMatthew Dillon int bcount; 171992da00bbSMatthew Dillon int i; 172092da00bbSMatthew Dillon 172189f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(object); 1722f6bcadc4SDavid Schultz if (object->type != OBJT_SWAP) 1723f6bcadc4SDavid Schultz return (0); 1724f6bcadc4SDavid Schultz 1725b3fed13eSDavid Schultz mtx_lock(&swhash_mtx); 172692da00bbSMatthew Dillon for (bcount = 0; bcount < object->un_pager.swp.swp_bcount; bcount++) { 172792da00bbSMatthew Dillon struct swblock *swap; 172892da00bbSMatthew Dillon 172992da00bbSMatthew Dillon if ((swap = *swp_pager_hash(object, index)) != NULL) { 173092da00bbSMatthew Dillon for (i = 0; i < SWAP_META_PAGES; ++i) { 1731b3fed13eSDavid Schultz if (swp_pager_isondev(swap->swb_pages[i], sp)) { 17327827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 1733b3fed13eSDavid Schultz return (1); 173492da00bbSMatthew Dillon } 173592da00bbSMatthew Dillon } 17367827d9b0SAlan Cox } 173792da00bbSMatthew Dillon index += SWAP_META_PAGES; 173892da00bbSMatthew Dillon } 1739b3fed13eSDavid Schultz mtx_unlock(&swhash_mtx); 1740b3fed13eSDavid Schultz return (0); 174192da00bbSMatthew Dillon } 174292da00bbSMatthew Dillon 174392da00bbSMatthew Dillon /* 174492da00bbSMatthew Dillon * SWP_PAGER_FORCE_PAGEIN() - force a swap block to be paged in 174592da00bbSMatthew Dillon * 174692da00bbSMatthew Dillon * This routine dissociates the page at the given index within a 174792da00bbSMatthew Dillon * swap block from its backing store, paging it in if necessary. 174892da00bbSMatthew Dillon * If the page is paged in, it is placed in the inactive queue, 174992da00bbSMatthew Dillon * since it had its backing store ripped out from under it. 175092da00bbSMatthew Dillon * We also attempt to swap in all other pages in the swap block, 175192da00bbSMatthew Dillon * we only guarantee that the one at the specified index is 175292da00bbSMatthew Dillon * paged in. 175392da00bbSMatthew Dillon * 175492da00bbSMatthew Dillon * XXX - The code to page the whole block in doesn't work, so we 175592da00bbSMatthew Dillon * revert to the one-by-one behavior for now. Sigh. 175692da00bbSMatthew Dillon */ 175762a59e8fSWarner Losh static inline void 1758b3fed13eSDavid Schultz swp_pager_force_pagein(vm_object_t object, vm_pindex_t pindex) 175992da00bbSMatthew Dillon { 176092da00bbSMatthew Dillon vm_page_t m; 176192da00bbSMatthew Dillon 176292da00bbSMatthew Dillon vm_object_pip_add(object, 1); 17635944de8eSKonstantin Belousov m = vm_page_grab(object, pindex, VM_ALLOC_NORMAL); 176492da00bbSMatthew Dillon if (m->valid == VM_PAGE_BITS_ALL) { 17650d8243ccSAttilio Rao vm_object_pip_wakeup(object); 176692da00bbSMatthew Dillon vm_page_dirty(m); 1767d061cdd5SAlan Cox vm_page_lock(m); 1768d061cdd5SAlan Cox vm_page_activate(m); 17692965a453SKip Macy vm_page_unlock(m); 1770c7aebda8SAttilio Rao vm_page_xunbusy(m); 177192da00bbSMatthew Dillon vm_pager_page_unswapped(m); 177292da00bbSMatthew Dillon return; 177392da00bbSMatthew Dillon } 177492da00bbSMatthew Dillon 1775b3fed13eSDavid Schultz if (swap_pager_getpages(object, &m, 1, 0) != VM_PAGER_OK) 177692da00bbSMatthew Dillon panic("swap_pager_force_pagein: read from swap failed");/*XXX*/ 17770d8243ccSAttilio Rao vm_object_pip_wakeup(object); 177892da00bbSMatthew Dillon vm_page_dirty(m); 1779db1f085eSAlan Cox vm_page_lock(m); 1780db1f085eSAlan Cox vm_page_deactivate(m); 17812965a453SKip Macy vm_page_unlock(m); 1782c7aebda8SAttilio Rao vm_page_xunbusy(m); 178392da00bbSMatthew Dillon vm_pager_page_unswapped(m); 178492da00bbSMatthew Dillon } 178592da00bbSMatthew Dillon 178692da00bbSMatthew Dillon /* 178792da00bbSMatthew Dillon * swap_pager_swapoff: 178892da00bbSMatthew Dillon * 178992da00bbSMatthew Dillon * Page in all of the pages that have been paged out to the 179092da00bbSMatthew Dillon * given device. The corresponding blocks in the bitmap must be 179192da00bbSMatthew Dillon * marked as allocated and the device must be flagged SW_CLOSING. 179292da00bbSMatthew Dillon * There may be no processes swapped out to the device. 179392da00bbSMatthew Dillon * 179492da00bbSMatthew Dillon * This routine may block. 179592da00bbSMatthew Dillon */ 1796e9c0cc15SPoul-Henning Kamp static void 1797b3fed13eSDavid Schultz swap_pager_swapoff(struct swdevt *sp) 179892da00bbSMatthew Dillon { 179992da00bbSMatthew Dillon struct swblock *swap; 18008bc61209SDavid Schultz int i, j, retries; 180192da00bbSMatthew Dillon 180292da00bbSMatthew Dillon GIANT_REQUIRED; 180392da00bbSMatthew Dillon 18048bc61209SDavid Schultz retries = 0; 180592da00bbSMatthew Dillon full_rescan: 1806b3fed13eSDavid Schultz mtx_lock(&swhash_mtx); 180792da00bbSMatthew Dillon for (i = 0; i <= swhash_mask; i++) { /* '<=' is correct here */ 180892da00bbSMatthew Dillon restart: 1809b3fed13eSDavid Schultz for (swap = swhash[i]; swap != NULL; swap = swap->swb_hnext) { 1810b3fed13eSDavid Schultz vm_object_t object = swap->swb_object; 1811b3fed13eSDavid Schultz vm_pindex_t pindex = swap->swb_index; 181292da00bbSMatthew Dillon for (j = 0; j < SWAP_META_PAGES; ++j) { 1813b3fed13eSDavid Schultz if (swp_pager_isondev(swap->swb_pages[j], sp)) { 1814b3fed13eSDavid Schultz /* avoid deadlock */ 181589f6b863SAttilio Rao if (!VM_OBJECT_TRYWLOCK(object)) { 181692da00bbSMatthew Dillon break; 1817b3fed13eSDavid Schultz } else { 1818b3fed13eSDavid Schultz mtx_unlock(&swhash_mtx); 1819b3fed13eSDavid Schultz swp_pager_force_pagein(object, 1820b3fed13eSDavid Schultz pindex + j); 182189f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 1822b3fed13eSDavid Schultz mtx_lock(&swhash_mtx); 182392da00bbSMatthew Dillon goto restart; 182492da00bbSMatthew Dillon } 1825b3fed13eSDavid Schultz } 1826b3fed13eSDavid Schultz } 1827b3fed13eSDavid Schultz } 182892da00bbSMatthew Dillon } 1829d536c58fSAlan Cox mtx_unlock(&swhash_mtx); 18308bc61209SDavid Schultz if (sp->sw_used) { 183192da00bbSMatthew Dillon /* 18328bc61209SDavid Schultz * Objects may be locked or paging to the device being 18338bc61209SDavid Schultz * removed, so we will miss their pages and need to 18348bc61209SDavid Schultz * make another pass. We have marked this device as 18358bc61209SDavid Schultz * SW_CLOSING, so the activity should finish soon. 183692da00bbSMatthew Dillon */ 18378bc61209SDavid Schultz retries++; 18388bc61209SDavid Schultz if (retries > 100) { 18398bc61209SDavid Schultz panic("swapoff: failed to locate %d swap blocks", 18408bc61209SDavid Schultz sp->sw_used); 18418bc61209SDavid Schultz } 18424d70511aSJohn Baldwin pause("swpoff", hz / 20); 184392da00bbSMatthew Dillon goto full_rescan; 184492da00bbSMatthew Dillon } 184592da00bbSMatthew Dillon } 184692da00bbSMatthew Dillon 18471c7c3c6aSMatthew Dillon /************************************************************************ 18481c7c3c6aSMatthew Dillon * SWAP META DATA * 18491c7c3c6aSMatthew Dillon ************************************************************************ 18501c7c3c6aSMatthew Dillon * 18511c7c3c6aSMatthew Dillon * These routines manipulate the swap metadata stored in the 1852cec9f109SDavid E. O'Brien * OBJT_SWAP object. 18531c7c3c6aSMatthew Dillon * 18544dcc5c2dSMatthew Dillon * Swap metadata is implemented with a global hash and not directly 18554dcc5c2dSMatthew Dillon * linked into the object. Instead the object simply contains 18564dcc5c2dSMatthew Dillon * appropriate tracking counters. 18571c7c3c6aSMatthew Dillon */ 18581c7c3c6aSMatthew Dillon 18591c7c3c6aSMatthew Dillon /* 18601c7c3c6aSMatthew Dillon * SWP_PAGER_META_BUILD() - add swap block to swap meta data for object 18611c7c3c6aSMatthew Dillon * 18621c7c3c6aSMatthew Dillon * We first convert the object to a swap object if it is a default 18631c7c3c6aSMatthew Dillon * object. 18641c7c3c6aSMatthew Dillon * 18651c7c3c6aSMatthew Dillon * The specified swapblk is added to the object's swap metadata. If 18661c7c3c6aSMatthew Dillon * the swapblk is not valid, it is freed instead. Any previously 18671c7c3c6aSMatthew Dillon * assigned swapblk is freed. 18681c7c3c6aSMatthew Dillon */ 18691c7c3c6aSMatthew Dillon static void 18702f249180SPoul-Henning Kamp swp_pager_meta_build(vm_object_t object, vm_pindex_t pindex, daddr_t swapblk) 18712f249180SPoul-Henning Kamp { 18723ff863f1SDag-Erling Smørgrav static volatile int exhausted; 18731c7c3c6aSMatthew Dillon struct swblock *swap; 18741c7c3c6aSMatthew Dillon struct swblock **pswap; 187523f09d50SIan Dowse int idx; 18761c7c3c6aSMatthew Dillon 187789f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(object); 18781c7c3c6aSMatthew Dillon /* 18791c7c3c6aSMatthew Dillon * Convert default object to swap object if necessary 18801c7c3c6aSMatthew Dillon */ 18811c7c3c6aSMatthew Dillon if (object->type != OBJT_SWAP) { 18821c7c3c6aSMatthew Dillon object->type = OBJT_SWAP; 18831c7c3c6aSMatthew Dillon object->un_pager.swp.swp_bcount = 0; 18841c7c3c6aSMatthew Dillon 18851c7c3c6aSMatthew Dillon if (object->handle != NULL) { 1886bd228075SAlan Cox mtx_lock(&sw_alloc_mtx); 18871c7c3c6aSMatthew Dillon TAILQ_INSERT_TAIL( 18881c7c3c6aSMatthew Dillon NOBJLIST(object->handle), 18891c7c3c6aSMatthew Dillon object, 18901c7c3c6aSMatthew Dillon pager_object_list 18911c7c3c6aSMatthew Dillon ); 1892a9fa2c05SAlfred Perlstein mtx_unlock(&sw_alloc_mtx); 18931c7c3c6aSMatthew Dillon } 1894bd228075SAlan Cox } 18951c7c3c6aSMatthew Dillon 18961c7c3c6aSMatthew Dillon /* 18971c7c3c6aSMatthew Dillon * Locate hash entry. If not found create, but if we aren't adding 18984dcc5c2dSMatthew Dillon * anything just return. If we run out of space in the map we wait 18994dcc5c2dSMatthew Dillon * and, since the hash table may have changed, retry. 19001c7c3c6aSMatthew Dillon */ 19014dcc5c2dSMatthew Dillon retry: 19027827d9b0SAlan Cox mtx_lock(&swhash_mtx); 190323f09d50SIan Dowse pswap = swp_pager_hash(object, pindex); 19041c7c3c6aSMatthew Dillon 19051c7c3c6aSMatthew Dillon if ((swap = *pswap) == NULL) { 19061c7c3c6aSMatthew Dillon int i; 19071c7c3c6aSMatthew Dillon 19081c7c3c6aSMatthew Dillon if (swapblk == SWAPBLK_NONE) 19097827d9b0SAlan Cox goto done; 19101c7c3c6aSMatthew Dillon 19115a3c920fSKonstantin Belousov swap = *pswap = uma_zalloc(swap_zone, M_NOWAIT | 19125a3c920fSKonstantin Belousov (curproc == pageproc ? M_USE_RESERVE : 0)); 19134dcc5c2dSMatthew Dillon if (swap == NULL) { 19147827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 191589f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 19162025d69bSKonstantin Belousov if (uma_zone_exhausted(swap_zone)) { 1917dc1b35b5SDag-Erling Smørgrav if (atomic_cmpset_int(&exhausted, 0, 1)) 19183ff863f1SDag-Erling Smørgrav printf("swap zone exhausted, " 19193ff863f1SDag-Erling Smørgrav "increase kern.maxswzone\n"); 19202025d69bSKonstantin Belousov vm_pageout_oom(VM_OOM_SWAPZ); 19212025d69bSKonstantin Belousov pause("swzonex", 10); 19222025d69bSKonstantin Belousov } else 19234dcc5c2dSMatthew Dillon VM_WAIT; 192489f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 19254dcc5c2dSMatthew Dillon goto retry; 19264dcc5c2dSMatthew Dillon } 1927670d17b5SJeff Roberson 1928dc1b35b5SDag-Erling Smørgrav if (atomic_cmpset_int(&exhausted, 1, 0)) 19293ff863f1SDag-Erling Smørgrav printf("swap zone ok\n"); 19303ff863f1SDag-Erling Smørgrav 19311c7c3c6aSMatthew Dillon swap->swb_hnext = NULL; 19321c7c3c6aSMatthew Dillon swap->swb_object = object; 193323f09d50SIan Dowse swap->swb_index = pindex & ~(vm_pindex_t)SWAP_META_MASK; 19341c7c3c6aSMatthew Dillon swap->swb_count = 0; 19351c7c3c6aSMatthew Dillon 19361c7c3c6aSMatthew Dillon ++object->un_pager.swp.swp_bcount; 19371c7c3c6aSMatthew Dillon 19381c7c3c6aSMatthew Dillon for (i = 0; i < SWAP_META_PAGES; ++i) 19391c7c3c6aSMatthew Dillon swap->swb_pages[i] = SWAPBLK_NONE; 19401c7c3c6aSMatthew Dillon } 19411c7c3c6aSMatthew Dillon 19421c7c3c6aSMatthew Dillon /* 19431c7c3c6aSMatthew Dillon * Delete prior contents of metadata 19441c7c3c6aSMatthew Dillon */ 194523f09d50SIan Dowse idx = pindex & SWAP_META_MASK; 19461c7c3c6aSMatthew Dillon 194723f09d50SIan Dowse if (swap->swb_pages[idx] != SWAPBLK_NONE) { 194823f09d50SIan Dowse swp_pager_freeswapspace(swap->swb_pages[idx], 1); 19491c7c3c6aSMatthew Dillon --swap->swb_count; 19501c7c3c6aSMatthew Dillon } 19511c7c3c6aSMatthew Dillon 19521c7c3c6aSMatthew Dillon /* 19531c7c3c6aSMatthew Dillon * Enter block into metadata 19541c7c3c6aSMatthew Dillon */ 195523f09d50SIan Dowse swap->swb_pages[idx] = swapblk; 19564dcc5c2dSMatthew Dillon if (swapblk != SWAPBLK_NONE) 19571c7c3c6aSMatthew Dillon ++swap->swb_count; 19587827d9b0SAlan Cox done: 19597827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 19601c7c3c6aSMatthew Dillon } 19611c7c3c6aSMatthew Dillon 19621c7c3c6aSMatthew Dillon /* 19631c7c3c6aSMatthew Dillon * SWP_PAGER_META_FREE() - free a range of blocks in the object's swap metadata 19641c7c3c6aSMatthew Dillon * 19651c7c3c6aSMatthew Dillon * The requested range of blocks is freed, with any associated swap 19661c7c3c6aSMatthew Dillon * returned to the swap bitmap. 19671c7c3c6aSMatthew Dillon * 19681c7c3c6aSMatthew Dillon * This routine will free swap metadata structures as they are cleaned 19691c7c3c6aSMatthew Dillon * out. This routine does *NOT* operate on swap metadata associated 19701c7c3c6aSMatthew Dillon * with resident pages. 19711c7c3c6aSMatthew Dillon */ 19721c7c3c6aSMatthew Dillon static void 19734dcc5c2dSMatthew Dillon swp_pager_meta_free(vm_object_t object, vm_pindex_t index, daddr_t count) 19741c7c3c6aSMatthew Dillon { 19752928cef7SAlan Cox 1976c25673ffSAttilio Rao VM_OBJECT_ASSERT_LOCKED(object); 19771c7c3c6aSMatthew Dillon if (object->type != OBJT_SWAP) 19781c7c3c6aSMatthew Dillon return; 19791c7c3c6aSMatthew Dillon 19801c7c3c6aSMatthew Dillon while (count > 0) { 19811c7c3c6aSMatthew Dillon struct swblock **pswap; 19821c7c3c6aSMatthew Dillon struct swblock *swap; 19831c7c3c6aSMatthew Dillon 19847827d9b0SAlan Cox mtx_lock(&swhash_mtx); 19851c7c3c6aSMatthew Dillon pswap = swp_pager_hash(object, index); 19861c7c3c6aSMatthew Dillon 19871c7c3c6aSMatthew Dillon if ((swap = *pswap) != NULL) { 19881c7c3c6aSMatthew Dillon daddr_t v = swap->swb_pages[index & SWAP_META_MASK]; 19891c7c3c6aSMatthew Dillon 19901c7c3c6aSMatthew Dillon if (v != SWAPBLK_NONE) { 19911c7c3c6aSMatthew Dillon swp_pager_freeswapspace(v, 1); 19921c7c3c6aSMatthew Dillon swap->swb_pages[index & SWAP_META_MASK] = 19931c7c3c6aSMatthew Dillon SWAPBLK_NONE; 19941c7c3c6aSMatthew Dillon if (--swap->swb_count == 0) { 19951c7c3c6aSMatthew Dillon *pswap = swap->swb_hnext; 1996670d17b5SJeff Roberson uma_zfree(swap_zone, swap); 19971c7c3c6aSMatthew Dillon --object->un_pager.swp.swp_bcount; 19981c7c3c6aSMatthew Dillon } 19991c7c3c6aSMatthew Dillon } 20001c7c3c6aSMatthew Dillon --count; 20011c7c3c6aSMatthew Dillon ++index; 20021c7c3c6aSMatthew Dillon } else { 20034dcc5c2dSMatthew Dillon int n = SWAP_META_PAGES - (index & SWAP_META_MASK); 20041c7c3c6aSMatthew Dillon count -= n; 20051c7c3c6aSMatthew Dillon index += n; 20061c7c3c6aSMatthew Dillon } 20077827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 20081c7c3c6aSMatthew Dillon } 20091c7c3c6aSMatthew Dillon } 20101c7c3c6aSMatthew Dillon 20111c7c3c6aSMatthew Dillon /* 20121c7c3c6aSMatthew Dillon * SWP_PAGER_META_FREE_ALL() - destroy all swap metadata associated with object 20131c7c3c6aSMatthew Dillon * 20141c7c3c6aSMatthew Dillon * This routine locates and destroys all swap metadata associated with 20151c7c3c6aSMatthew Dillon * an object. 20161c7c3c6aSMatthew Dillon */ 20171c7c3c6aSMatthew Dillon static void 20181c7c3c6aSMatthew Dillon swp_pager_meta_free_all(vm_object_t object) 20191c7c3c6aSMatthew Dillon { 20201c7c3c6aSMatthew Dillon daddr_t index = 0; 20211c7c3c6aSMatthew Dillon 202289f6b863SAttilio Rao VM_OBJECT_ASSERT_WLOCKED(object); 20231c7c3c6aSMatthew Dillon if (object->type != OBJT_SWAP) 20241c7c3c6aSMatthew Dillon return; 20251c7c3c6aSMatthew Dillon 20261c7c3c6aSMatthew Dillon while (object->un_pager.swp.swp_bcount) { 20271c7c3c6aSMatthew Dillon struct swblock **pswap; 20281c7c3c6aSMatthew Dillon struct swblock *swap; 20291c7c3c6aSMatthew Dillon 20307827d9b0SAlan Cox mtx_lock(&swhash_mtx); 20311c7c3c6aSMatthew Dillon pswap = swp_pager_hash(object, index); 20321c7c3c6aSMatthew Dillon if ((swap = *pswap) != NULL) { 20331c7c3c6aSMatthew Dillon int i; 20341c7c3c6aSMatthew Dillon 20351c7c3c6aSMatthew Dillon for (i = 0; i < SWAP_META_PAGES; ++i) { 20361c7c3c6aSMatthew Dillon daddr_t v = swap->swb_pages[i]; 20371c7c3c6aSMatthew Dillon if (v != SWAPBLK_NONE) { 20381c7c3c6aSMatthew Dillon --swap->swb_count; 20394dcc5c2dSMatthew Dillon swp_pager_freeswapspace(v, 1); 20401c7c3c6aSMatthew Dillon } 20411c7c3c6aSMatthew Dillon } 20421c7c3c6aSMatthew Dillon if (swap->swb_count != 0) 20431c7c3c6aSMatthew Dillon panic("swap_pager_meta_free_all: swb_count != 0"); 20441c7c3c6aSMatthew Dillon *pswap = swap->swb_hnext; 2045670d17b5SJeff Roberson uma_zfree(swap_zone, swap); 20461c7c3c6aSMatthew Dillon --object->un_pager.swp.swp_bcount; 20471c7c3c6aSMatthew Dillon } 20487827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 20491c7c3c6aSMatthew Dillon index += SWAP_META_PAGES; 20501c7c3c6aSMatthew Dillon } 20511c7c3c6aSMatthew Dillon } 20521c7c3c6aSMatthew Dillon 20531c7c3c6aSMatthew Dillon /* 20541c7c3c6aSMatthew Dillon * SWP_PAGER_METACTL() - misc control of swap and vm_page_t meta data. 20551c7c3c6aSMatthew Dillon * 20561c7c3c6aSMatthew Dillon * This routine is capable of looking up, popping, or freeing 20571c7c3c6aSMatthew Dillon * swapblk assignments in the swap meta data or in the vm_page_t. 20581c7c3c6aSMatthew Dillon * The routine typically returns the swapblk being looked-up, or popped, 20591c7c3c6aSMatthew Dillon * or SWAPBLK_NONE if the block was freed, or SWAPBLK_NONE if the block 20601c7c3c6aSMatthew Dillon * was invalid. This routine will automatically free any invalid 20611c7c3c6aSMatthew Dillon * meta-data swapblks. 20621c7c3c6aSMatthew Dillon * 20631c7c3c6aSMatthew Dillon * It is not possible to store invalid swapblks in the swap meta data 20641c7c3c6aSMatthew Dillon * (other then a literal 'SWAPBLK_NONE'), so we don't bother checking. 20651c7c3c6aSMatthew Dillon * 20661c7c3c6aSMatthew Dillon * When acting on a busy resident page and paging is in progress, we 20671c7c3c6aSMatthew Dillon * have to wait until paging is complete but otherwise can act on the 20681c7c3c6aSMatthew Dillon * busy page. 20691c7c3c6aSMatthew Dillon * 20704dcc5c2dSMatthew Dillon * SWM_FREE remove and free swap block from metadata 20711c7c3c6aSMatthew Dillon * SWM_POP remove from meta data but do not free.. pop it out 20721c7c3c6aSMatthew Dillon */ 20731c7c3c6aSMatthew Dillon static daddr_t 20742f249180SPoul-Henning Kamp swp_pager_meta_ctl(vm_object_t object, vm_pindex_t pindex, int flags) 20752f249180SPoul-Henning Kamp { 20764dcc5c2dSMatthew Dillon struct swblock **pswap; 20774dcc5c2dSMatthew Dillon struct swblock *swap; 20784dcc5c2dSMatthew Dillon daddr_t r1; 207923f09d50SIan Dowse int idx; 20804dcc5c2dSMatthew Dillon 2081c25673ffSAttilio Rao VM_OBJECT_ASSERT_LOCKED(object); 20821c7c3c6aSMatthew Dillon /* 20831c7c3c6aSMatthew Dillon * The meta data only exists of the object is OBJT_SWAP 20841c7c3c6aSMatthew Dillon * and even then might not be allocated yet. 20851c7c3c6aSMatthew Dillon */ 20864dcc5c2dSMatthew Dillon if (object->type != OBJT_SWAP) 20871c7c3c6aSMatthew Dillon return (SWAPBLK_NONE); 20881c7c3c6aSMatthew Dillon 20894dcc5c2dSMatthew Dillon r1 = SWAPBLK_NONE; 20907827d9b0SAlan Cox mtx_lock(&swhash_mtx); 209123f09d50SIan Dowse pswap = swp_pager_hash(object, pindex); 20921c7c3c6aSMatthew Dillon 20931c7c3c6aSMatthew Dillon if ((swap = *pswap) != NULL) { 209423f09d50SIan Dowse idx = pindex & SWAP_META_MASK; 209523f09d50SIan Dowse r1 = swap->swb_pages[idx]; 20961c7c3c6aSMatthew Dillon 20971c7c3c6aSMatthew Dillon if (r1 != SWAPBLK_NONE) { 20981c7c3c6aSMatthew Dillon if (flags & SWM_FREE) { 20994dcc5c2dSMatthew Dillon swp_pager_freeswapspace(r1, 1); 21001c7c3c6aSMatthew Dillon r1 = SWAPBLK_NONE; 21011c7c3c6aSMatthew Dillon } 21021c7c3c6aSMatthew Dillon if (flags & (SWM_FREE|SWM_POP)) { 210323f09d50SIan Dowse swap->swb_pages[idx] = SWAPBLK_NONE; 21041c7c3c6aSMatthew Dillon if (--swap->swb_count == 0) { 21051c7c3c6aSMatthew Dillon *pswap = swap->swb_hnext; 2106670d17b5SJeff Roberson uma_zfree(swap_zone, swap); 21071c7c3c6aSMatthew Dillon --object->un_pager.swp.swp_bcount; 21081c7c3c6aSMatthew Dillon } 21091c7c3c6aSMatthew Dillon } 21101c7c3c6aSMatthew Dillon } 21111c7c3c6aSMatthew Dillon } 21127827d9b0SAlan Cox mtx_unlock(&swhash_mtx); 21131c7c3c6aSMatthew Dillon return (r1); 21141c7c3c6aSMatthew Dillon } 21151c7c3c6aSMatthew Dillon 2116e9c0cc15SPoul-Henning Kamp /* 2117e9c0cc15SPoul-Henning Kamp * System call swapon(name) enables swapping on device name, 2118e9c0cc15SPoul-Henning Kamp * which must be in the swdevsw. Return EBUSY 2119e9c0cc15SPoul-Henning Kamp * if already swapping on this device. 2120e9c0cc15SPoul-Henning Kamp */ 2121e9c0cc15SPoul-Henning Kamp #ifndef _SYS_SYSPROTO_H_ 2122e9c0cc15SPoul-Henning Kamp struct swapon_args { 2123e9c0cc15SPoul-Henning Kamp char *name; 2124e9c0cc15SPoul-Henning Kamp }; 2125e9c0cc15SPoul-Henning Kamp #endif 2126e9c0cc15SPoul-Henning Kamp 2127e9c0cc15SPoul-Henning Kamp /* 2128e9c0cc15SPoul-Henning Kamp * MPSAFE 2129e9c0cc15SPoul-Henning Kamp */ 2130e9c0cc15SPoul-Henning Kamp /* ARGSUSED */ 2131e9c0cc15SPoul-Henning Kamp int 21328451d0ddSKip Macy sys_swapon(struct thread *td, struct swapon_args *uap) 2133e9c0cc15SPoul-Henning Kamp { 2134e9c0cc15SPoul-Henning Kamp struct vattr attr; 2135e9c0cc15SPoul-Henning Kamp struct vnode *vp; 2136e9c0cc15SPoul-Henning Kamp struct nameidata nd; 2137e9c0cc15SPoul-Henning Kamp int error; 2138e9c0cc15SPoul-Henning Kamp 2139acd3428bSRobert Watson error = priv_check(td, PRIV_SWAPON); 2140e9c0cc15SPoul-Henning Kamp if (error) 2141acd3428bSRobert Watson return (error); 2142e9c0cc15SPoul-Henning Kamp 2143acd3428bSRobert Watson mtx_lock(&Giant); 2144e9c0cc15SPoul-Henning Kamp while (swdev_syscall_active) 2145e9c0cc15SPoul-Henning Kamp tsleep(&swdev_syscall_active, PUSER - 1, "swpon", 0); 2146e9c0cc15SPoul-Henning Kamp swdev_syscall_active = 1; 2147e9c0cc15SPoul-Henning Kamp 2148e9c0cc15SPoul-Henning Kamp /* 2149e9c0cc15SPoul-Henning Kamp * Swap metadata may not fit in the KVM if we have physical 2150e9c0cc15SPoul-Henning Kamp * memory of >1GB. 2151e9c0cc15SPoul-Henning Kamp */ 2152e9c0cc15SPoul-Henning Kamp if (swap_zone == NULL) { 2153e9c0cc15SPoul-Henning Kamp error = ENOMEM; 2154e9c0cc15SPoul-Henning Kamp goto done; 2155e9c0cc15SPoul-Henning Kamp } 2156e9c0cc15SPoul-Henning Kamp 2157d9135e72SRobert Watson NDINIT(&nd, LOOKUP, ISOPEN | FOLLOW | AUDITVNODE1, UIO_USERSPACE, 2158d9135e72SRobert Watson uap->name, td); 2159e9c0cc15SPoul-Henning Kamp error = namei(&nd); 2160e9c0cc15SPoul-Henning Kamp if (error) 2161e9c0cc15SPoul-Henning Kamp goto done; 2162e9c0cc15SPoul-Henning Kamp 2163e9c0cc15SPoul-Henning Kamp NDFREE(&nd, NDF_ONLY_PNBUF); 2164e9c0cc15SPoul-Henning Kamp vp = nd.ni_vp; 2165e9c0cc15SPoul-Henning Kamp 216620da9c2eSPoul-Henning Kamp if (vn_isdisk(vp, &error)) { 2167dee34ca4SPoul-Henning Kamp error = swapongeom(td, vp); 216820da9c2eSPoul-Henning Kamp } else if (vp->v_type == VREG && 2169e9c0cc15SPoul-Henning Kamp (vp->v_mount->mnt_vfc->vfc_flags & VFCF_NETWORK) != 0 && 21700359a12eSAttilio Rao (error = VOP_GETATTR(vp, &attr, td->td_ucred)) == 0) { 2171e9c0cc15SPoul-Henning Kamp /* 2172e9c0cc15SPoul-Henning Kamp * Allow direct swapping to NFS regular files in the same 2173e9c0cc15SPoul-Henning Kamp * way that nfs_mountroot() sets up diskless swapping. 2174e9c0cc15SPoul-Henning Kamp */ 217559efee01SPoul-Henning Kamp error = swaponvp(td, vp, attr.va_size / DEV_BSIZE); 2176e9c0cc15SPoul-Henning Kamp } 2177e9c0cc15SPoul-Henning Kamp 2178e9c0cc15SPoul-Henning Kamp if (error) 2179e9c0cc15SPoul-Henning Kamp vrele(vp); 2180e9c0cc15SPoul-Henning Kamp done: 2181e9c0cc15SPoul-Henning Kamp swdev_syscall_active = 0; 2182e9c0cc15SPoul-Henning Kamp wakeup_one(&swdev_syscall_active); 2183e9c0cc15SPoul-Henning Kamp mtx_unlock(&Giant); 2184e9c0cc15SPoul-Henning Kamp return (error); 2185e9c0cc15SPoul-Henning Kamp } 2186e9c0cc15SPoul-Henning Kamp 21873ff863f1SDag-Erling Smørgrav /* 21883ff863f1SDag-Erling Smørgrav * Check that the total amount of swap currently configured does not 21893ff863f1SDag-Erling Smørgrav * exceed half the theoretical maximum. If it does, print a warning 21903ff863f1SDag-Erling Smørgrav * message and return -1; otherwise, return 0. 21913ff863f1SDag-Erling Smørgrav */ 21923ff863f1SDag-Erling Smørgrav static int 21933ff863f1SDag-Erling Smørgrav swapon_check_swzone(unsigned long npages) 21943ff863f1SDag-Erling Smørgrav { 21953ff863f1SDag-Erling Smørgrav unsigned long maxpages; 21963ff863f1SDag-Erling Smørgrav 21973ff863f1SDag-Erling Smørgrav /* absolute maximum we can handle assuming 100% efficiency */ 21983ff863f1SDag-Erling Smørgrav maxpages = uma_zone_get_max(swap_zone) * SWAP_META_PAGES; 21993ff863f1SDag-Erling Smørgrav 22003ff863f1SDag-Erling Smørgrav /* recommend using no more than half that amount */ 22013ff863f1SDag-Erling Smørgrav if (npages > maxpages / 2) { 22023ff863f1SDag-Erling Smørgrav printf("warning: total configured swap (%lu pages) " 22033ff863f1SDag-Erling Smørgrav "exceeds maximum recommended amount (%lu pages).\n", 22049462305cSSergey Kandaurov npages, maxpages / 2); 22053ff863f1SDag-Erling Smørgrav printf("warning: increase kern.maxswzone " 22063ff863f1SDag-Erling Smørgrav "or reduce amount of swap.\n"); 22073ff863f1SDag-Erling Smørgrav return (-1); 22083ff863f1SDag-Erling Smørgrav } 22093ff863f1SDag-Erling Smørgrav return (0); 22103ff863f1SDag-Erling Smørgrav } 22113ff863f1SDag-Erling Smørgrav 221259efee01SPoul-Henning Kamp static void 22132cc718a1SKonstantin Belousov swaponsomething(struct vnode *vp, void *id, u_long nblks, 22142cc718a1SKonstantin Belousov sw_strategy_t *strategy, sw_close_t *close, dev_t dev, int flags) 2215e9c0cc15SPoul-Henning Kamp { 22162d9974c1SAlan Cox struct swdevt *sp, *tsp; 2217e9c0cc15SPoul-Henning Kamp swblk_t dvbase; 22188f60c087SPoul-Henning Kamp u_long mblocks; 2219e9c0cc15SPoul-Henning Kamp 2220e9c0cc15SPoul-Henning Kamp /* 2221e9c0cc15SPoul-Henning Kamp * nblks is in DEV_BSIZE'd chunks, convert to PAGE_SIZE'd chunks. 2222e9c0cc15SPoul-Henning Kamp * First chop nblks off to page-align it, then convert. 2223e9c0cc15SPoul-Henning Kamp * 2224e9c0cc15SPoul-Henning Kamp * sw->sw_nblks is in page-sized chunks now too. 2225e9c0cc15SPoul-Henning Kamp */ 2226e9c0cc15SPoul-Henning Kamp nblks &= ~(ctodb(1) - 1); 2227e9c0cc15SPoul-Henning Kamp nblks = dbtoc(nblks); 2228e9c0cc15SPoul-Henning Kamp 22296e903bd0SKonstantin Belousov /* 22306e903bd0SKonstantin Belousov * If we go beyond this, we get overflows in the radix 22316e903bd0SKonstantin Belousov * tree bitmap code. 22326e903bd0SKonstantin Belousov */ 22336e903bd0SKonstantin Belousov mblocks = 0x40000000 / BLIST_META_RADIX; 22346e903bd0SKonstantin Belousov if (nblks > mblocks) { 22356e903bd0SKonstantin Belousov printf( 22366e903bd0SKonstantin Belousov "WARNING: reducing swap size to maximum of %luMB per unit\n", 22376e903bd0SKonstantin Belousov mblocks / 1024 / 1024 * PAGE_SIZE); 22386e903bd0SKonstantin Belousov nblks = mblocks; 22396e903bd0SKonstantin Belousov } 22406e903bd0SKonstantin Belousov 22418f60c087SPoul-Henning Kamp sp = malloc(sizeof *sp, M_VMPGDATA, M_WAITOK | M_ZERO); 2242dee34ca4SPoul-Henning Kamp sp->sw_vp = vp; 2243dee34ca4SPoul-Henning Kamp sp->sw_id = id; 2244f3732fd1SPoul-Henning Kamp sp->sw_dev = dev; 22458d677ef9SPoul-Henning Kamp sp->sw_flags = 0; 2246e9c0cc15SPoul-Henning Kamp sp->sw_nblks = nblks; 2247e9c0cc15SPoul-Henning Kamp sp->sw_used = 0; 224859efee01SPoul-Henning Kamp sp->sw_strategy = strategy; 2249dee34ca4SPoul-Henning Kamp sp->sw_close = close; 22502cc718a1SKonstantin Belousov sp->sw_flags = flags; 2251e9c0cc15SPoul-Henning Kamp 2252c8c7ad92SKip Macy sp->sw_blist = blist_create(nblks, M_WAITOK); 2253e9c0cc15SPoul-Henning Kamp /* 2254ef3c5abdSPoul-Henning Kamp * Do not free the first two block in order to avoid overwriting 22558f60c087SPoul-Henning Kamp * any bsd label at the front of the partition 2256e9c0cc15SPoul-Henning Kamp */ 2257ef3c5abdSPoul-Henning Kamp blist_free(sp->sw_blist, 2, nblks - 2); 2258e9c0cc15SPoul-Henning Kamp 22592d9974c1SAlan Cox dvbase = 0; 226020da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 22612d9974c1SAlan Cox TAILQ_FOREACH(tsp, &swtailq, sw_list) { 22622d9974c1SAlan Cox if (tsp->sw_end >= dvbase) { 22632d9974c1SAlan Cox /* 22642d9974c1SAlan Cox * We put one uncovered page between the devices 22652d9974c1SAlan Cox * in order to definitively prevent any cross-device 22662d9974c1SAlan Cox * I/O requests 22672d9974c1SAlan Cox */ 22682d9974c1SAlan Cox dvbase = tsp->sw_end + 1; 22692d9974c1SAlan Cox } 22702d9974c1SAlan Cox } 22712d9974c1SAlan Cox sp->sw_first = dvbase; 22722d9974c1SAlan Cox sp->sw_end = dvbase + nblks; 22738f60c087SPoul-Henning Kamp TAILQ_INSERT_TAIL(&swtailq, sp, sw_list); 22748f60c087SPoul-Henning Kamp nswapdev++; 22758f60c087SPoul-Henning Kamp swap_pager_avail += nblks; 22763364c323SKonstantin Belousov swap_total += (vm_ooffset_t)nblks * PAGE_SIZE; 22773ff863f1SDag-Erling Smørgrav swapon_check_swzone(swap_total / PAGE_SIZE); 2278d05bc129SAlan Cox swp_sizecheck(); 2279d05bc129SAlan Cox mtx_unlock(&sw_dev_mtx); 228059efee01SPoul-Henning Kamp } 2281e9c0cc15SPoul-Henning Kamp 2282e9c0cc15SPoul-Henning Kamp /* 2283e9c0cc15SPoul-Henning Kamp * SYSCALL: swapoff(devname) 2284e9c0cc15SPoul-Henning Kamp * 2285e9c0cc15SPoul-Henning Kamp * Disable swapping on the given device. 2286dee34ca4SPoul-Henning Kamp * 2287dee34ca4SPoul-Henning Kamp * XXX: Badly designed system call: it should use a device index 2288dee34ca4SPoul-Henning Kamp * rather than filename as specification. We keep sw_vp around 2289dee34ca4SPoul-Henning Kamp * only to make this work. 2290e9c0cc15SPoul-Henning Kamp */ 2291e9c0cc15SPoul-Henning Kamp #ifndef _SYS_SYSPROTO_H_ 2292e9c0cc15SPoul-Henning Kamp struct swapoff_args { 2293e9c0cc15SPoul-Henning Kamp char *name; 2294e9c0cc15SPoul-Henning Kamp }; 2295e9c0cc15SPoul-Henning Kamp #endif 2296e9c0cc15SPoul-Henning Kamp 2297e9c0cc15SPoul-Henning Kamp /* 2298e9c0cc15SPoul-Henning Kamp * MPSAFE 2299e9c0cc15SPoul-Henning Kamp */ 2300e9c0cc15SPoul-Henning Kamp /* ARGSUSED */ 2301e9c0cc15SPoul-Henning Kamp int 23028451d0ddSKip Macy sys_swapoff(struct thread *td, struct swapoff_args *uap) 2303e9c0cc15SPoul-Henning Kamp { 2304e9c0cc15SPoul-Henning Kamp struct vnode *vp; 2305e9c0cc15SPoul-Henning Kamp struct nameidata nd; 2306e9c0cc15SPoul-Henning Kamp struct swdevt *sp; 23078f60c087SPoul-Henning Kamp int error; 2308e9c0cc15SPoul-Henning Kamp 2309acd3428bSRobert Watson error = priv_check(td, PRIV_SWAPOFF); 2310e9c0cc15SPoul-Henning Kamp if (error) 23110909f38aSPawel Jakub Dawidek return (error); 2312e9c0cc15SPoul-Henning Kamp 23130909f38aSPawel Jakub Dawidek mtx_lock(&Giant); 2314e9c0cc15SPoul-Henning Kamp while (swdev_syscall_active) 2315e9c0cc15SPoul-Henning Kamp tsleep(&swdev_syscall_active, PUSER - 1, "swpoff", 0); 2316e9c0cc15SPoul-Henning Kamp swdev_syscall_active = 1; 2317e9c0cc15SPoul-Henning Kamp 2318d9135e72SRobert Watson NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNODE1, UIO_USERSPACE, uap->name, 2319d9135e72SRobert Watson td); 2320e9c0cc15SPoul-Henning Kamp error = namei(&nd); 2321e9c0cc15SPoul-Henning Kamp if (error) 2322e9c0cc15SPoul-Henning Kamp goto done; 2323e9c0cc15SPoul-Henning Kamp NDFREE(&nd, NDF_ONLY_PNBUF); 2324e9c0cc15SPoul-Henning Kamp vp = nd.ni_vp; 2325e9c0cc15SPoul-Henning Kamp 232620da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 23278f60c087SPoul-Henning Kamp TAILQ_FOREACH(sp, &swtailq, sw_list) { 2328dee34ca4SPoul-Henning Kamp if (sp->sw_vp == vp) 23290909f38aSPawel Jakub Dawidek break; 2330e9c0cc15SPoul-Henning Kamp } 233120da9c2eSPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 23320909f38aSPawel Jakub Dawidek if (sp == NULL) { 2333e9c0cc15SPoul-Henning Kamp error = EINVAL; 2334e9c0cc15SPoul-Henning Kamp goto done; 23350909f38aSPawel Jakub Dawidek } 233635918c55SChristian S.J. Peron error = swapoff_one(sp, td->td_ucred); 23370909f38aSPawel Jakub Dawidek done: 23380909f38aSPawel Jakub Dawidek swdev_syscall_active = 0; 23390909f38aSPawel Jakub Dawidek wakeup_one(&swdev_syscall_active); 23400909f38aSPawel Jakub Dawidek mtx_unlock(&Giant); 23410909f38aSPawel Jakub Dawidek return (error); 23420909f38aSPawel Jakub Dawidek } 23430909f38aSPawel Jakub Dawidek 23440909f38aSPawel Jakub Dawidek static int 234535918c55SChristian S.J. Peron swapoff_one(struct swdevt *sp, struct ucred *cred) 23460909f38aSPawel Jakub Dawidek { 23470909f38aSPawel Jakub Dawidek u_long nblks, dvbase; 2348e9c0cc15SPoul-Henning Kamp #ifdef MAC 23490909f38aSPawel Jakub Dawidek int error; 2350e9c0cc15SPoul-Henning Kamp #endif 2351e9c0cc15SPoul-Henning Kamp 23520909f38aSPawel Jakub Dawidek mtx_assert(&Giant, MA_OWNED); 23530909f38aSPawel Jakub Dawidek #ifdef MAC 2354cb05b60aSAttilio Rao (void) vn_lock(sp->sw_vp, LK_EXCLUSIVE | LK_RETRY); 235535918c55SChristian S.J. Peron error = mac_system_check_swapoff(cred, sp->sw_vp); 235622db15c0SAttilio Rao (void) VOP_UNLOCK(sp->sw_vp, 0); 23570909f38aSPawel Jakub Dawidek if (error != 0) 23580909f38aSPawel Jakub Dawidek return (error); 23590909f38aSPawel Jakub Dawidek #endif 2360e9c0cc15SPoul-Henning Kamp nblks = sp->sw_nblks; 2361e9c0cc15SPoul-Henning Kamp 2362e9c0cc15SPoul-Henning Kamp /* 2363e9c0cc15SPoul-Henning Kamp * We can turn off this swap device safely only if the 2364e9c0cc15SPoul-Henning Kamp * available virtual memory in the system will fit the amount 2365e9c0cc15SPoul-Henning Kamp * of data we will have to page back in, plus an epsilon so 2366e9c0cc15SPoul-Henning Kamp * the system doesn't become critically low on swap space. 2367e9c0cc15SPoul-Henning Kamp */ 236844f1c916SBryan Drewery if (vm_cnt.v_free_count + vm_cnt.v_cache_count + swap_pager_avail < 23692feb50bfSAttilio Rao nblks + nswap_lowat) { 23700909f38aSPawel Jakub Dawidek return (ENOMEM); 2371e9c0cc15SPoul-Henning Kamp } 2372e9c0cc15SPoul-Henning Kamp 2373e9c0cc15SPoul-Henning Kamp /* 2374e9c0cc15SPoul-Henning Kamp * Prevent further allocations on this device. 2375e9c0cc15SPoul-Henning Kamp */ 23762928cef7SAlan Cox mtx_lock(&sw_dev_mtx); 2377e9c0cc15SPoul-Henning Kamp sp->sw_flags |= SW_CLOSING; 23788f60c087SPoul-Henning Kamp for (dvbase = 0; dvbase < sp->sw_end; dvbase += dmmax) { 23798f60c087SPoul-Henning Kamp swap_pager_avail -= blist_fill(sp->sw_blist, 23808f60c087SPoul-Henning Kamp dvbase, dmmax); 2381e9c0cc15SPoul-Henning Kamp } 23823364c323SKonstantin Belousov swap_total -= (vm_ooffset_t)nblks * PAGE_SIZE; 23832928cef7SAlan Cox mtx_unlock(&sw_dev_mtx); 2384e9c0cc15SPoul-Henning Kamp 2385e9c0cc15SPoul-Henning Kamp /* 2386e9c0cc15SPoul-Henning Kamp * Page in the contents of the device and close it. 2387e9c0cc15SPoul-Henning Kamp */ 2388b3fed13eSDavid Schultz swap_pager_swapoff(sp); 2389e9c0cc15SPoul-Henning Kamp 239035918c55SChristian S.J. Peron sp->sw_close(curthread, sp); 239159efee01SPoul-Henning Kamp sp->sw_id = NULL; 239220da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 23938f60c087SPoul-Henning Kamp TAILQ_REMOVE(&swtailq, sp, sw_list); 23940676a140SAlan Cox nswapdev--; 23957dea2c2eSAlan Cox if (nswapdev == 0) { 23967dea2c2eSAlan Cox swap_pager_full = 2; 23977dea2c2eSAlan Cox swap_pager_almost_full = 1; 23987dea2c2eSAlan Cox } 23998f60c087SPoul-Henning Kamp if (swdevhd == sp) 24008f60c087SPoul-Henning Kamp swdevhd = NULL; 2401d05bc129SAlan Cox mtx_unlock(&sw_dev_mtx); 24028f60c087SPoul-Henning Kamp blist_destroy(sp->sw_blist); 24038f60c087SPoul-Henning Kamp free(sp, M_VMPGDATA); 24040909f38aSPawel Jakub Dawidek return (0); 24050909f38aSPawel Jakub Dawidek } 2406e9c0cc15SPoul-Henning Kamp 24070909f38aSPawel Jakub Dawidek void 24080909f38aSPawel Jakub Dawidek swapoff_all(void) 24090909f38aSPawel Jakub Dawidek { 24100909f38aSPawel Jakub Dawidek struct swdevt *sp, *spt; 24110909f38aSPawel Jakub Dawidek const char *devname; 24120909f38aSPawel Jakub Dawidek int error; 24130909f38aSPawel Jakub Dawidek 24140909f38aSPawel Jakub Dawidek mtx_lock(&Giant); 24150909f38aSPawel Jakub Dawidek while (swdev_syscall_active) 24160909f38aSPawel Jakub Dawidek tsleep(&swdev_syscall_active, PUSER - 1, "swpoff", 0); 24170909f38aSPawel Jakub Dawidek swdev_syscall_active = 1; 24180909f38aSPawel Jakub Dawidek 24190909f38aSPawel Jakub Dawidek mtx_lock(&sw_dev_mtx); 24200909f38aSPawel Jakub Dawidek TAILQ_FOREACH_SAFE(sp, &swtailq, sw_list, spt) { 24210909f38aSPawel Jakub Dawidek mtx_unlock(&sw_dev_mtx); 24220909f38aSPawel Jakub Dawidek if (vn_isdisk(sp->sw_vp, NULL)) 24237870adb6SEd Schouten devname = devtoname(sp->sw_vp->v_rdev); 24240909f38aSPawel Jakub Dawidek else 24250909f38aSPawel Jakub Dawidek devname = "[file]"; 242635918c55SChristian S.J. Peron error = swapoff_one(sp, thread0.td_ucred); 24270909f38aSPawel Jakub Dawidek if (error != 0) { 24280909f38aSPawel Jakub Dawidek printf("Cannot remove swap device %s (error=%d), " 24290909f38aSPawel Jakub Dawidek "skipping.\n", devname, error); 24300909f38aSPawel Jakub Dawidek } else if (bootverbose) { 24310909f38aSPawel Jakub Dawidek printf("Swap device %s removed.\n", devname); 24320909f38aSPawel Jakub Dawidek } 24330909f38aSPawel Jakub Dawidek mtx_lock(&sw_dev_mtx); 24340909f38aSPawel Jakub Dawidek } 24350909f38aSPawel Jakub Dawidek mtx_unlock(&sw_dev_mtx); 24360909f38aSPawel Jakub Dawidek 2437e9c0cc15SPoul-Henning Kamp swdev_syscall_active = 0; 2438e9c0cc15SPoul-Henning Kamp wakeup_one(&swdev_syscall_active); 2439e9c0cc15SPoul-Henning Kamp mtx_unlock(&Giant); 2440e9c0cc15SPoul-Henning Kamp } 2441e9c0cc15SPoul-Henning Kamp 2442567104a1SPoul-Henning Kamp void 2443567104a1SPoul-Henning Kamp swap_pager_status(int *total, int *used) 2444567104a1SPoul-Henning Kamp { 2445567104a1SPoul-Henning Kamp struct swdevt *sp; 2446567104a1SPoul-Henning Kamp 2447567104a1SPoul-Henning Kamp *total = 0; 2448567104a1SPoul-Henning Kamp *used = 0; 244920da9c2eSPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 24508f60c087SPoul-Henning Kamp TAILQ_FOREACH(sp, &swtailq, sw_list) { 2451567104a1SPoul-Henning Kamp *total += sp->sw_nblks; 2452567104a1SPoul-Henning Kamp *used += sp->sw_used; 2453567104a1SPoul-Henning Kamp } 245420da9c2eSPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 2455567104a1SPoul-Henning Kamp } 2456567104a1SPoul-Henning Kamp 2457dda4f960SKonstantin Belousov int 2458dda4f960SKonstantin Belousov swap_dev_info(int name, struct xswdev *xs, char *devname, size_t len) 2459dda4f960SKonstantin Belousov { 2460dda4f960SKonstantin Belousov struct swdevt *sp; 24617870adb6SEd Schouten const char *tmp_devname; 2462dda4f960SKonstantin Belousov int error, n; 2463dda4f960SKonstantin Belousov 2464dda4f960SKonstantin Belousov n = 0; 2465dda4f960SKonstantin Belousov error = ENOENT; 2466dda4f960SKonstantin Belousov mtx_lock(&sw_dev_mtx); 2467dda4f960SKonstantin Belousov TAILQ_FOREACH(sp, &swtailq, sw_list) { 2468dda4f960SKonstantin Belousov if (n != name) { 2469dda4f960SKonstantin Belousov n++; 2470dda4f960SKonstantin Belousov continue; 2471dda4f960SKonstantin Belousov } 2472dda4f960SKonstantin Belousov xs->xsw_version = XSWDEV_VERSION; 2473dda4f960SKonstantin Belousov xs->xsw_dev = sp->sw_dev; 2474dda4f960SKonstantin Belousov xs->xsw_flags = sp->sw_flags; 2475dda4f960SKonstantin Belousov xs->xsw_nblks = sp->sw_nblks; 2476dda4f960SKonstantin Belousov xs->xsw_used = sp->sw_used; 2477dda4f960SKonstantin Belousov if (devname != NULL) { 2478dda4f960SKonstantin Belousov if (vn_isdisk(sp->sw_vp, NULL)) 24797870adb6SEd Schouten tmp_devname = devtoname(sp->sw_vp->v_rdev); 2480dda4f960SKonstantin Belousov else 2481dda4f960SKonstantin Belousov tmp_devname = "[file]"; 2482dda4f960SKonstantin Belousov strncpy(devname, tmp_devname, len); 2483dda4f960SKonstantin Belousov } 2484dda4f960SKonstantin Belousov error = 0; 2485dda4f960SKonstantin Belousov break; 2486dda4f960SKonstantin Belousov } 2487dda4f960SKonstantin Belousov mtx_unlock(&sw_dev_mtx); 2488dda4f960SKonstantin Belousov return (error); 2489dda4f960SKonstantin Belousov } 2490dda4f960SKonstantin Belousov 2491e9c0cc15SPoul-Henning Kamp static int 2492e9c0cc15SPoul-Henning Kamp sysctl_vm_swap_info(SYSCTL_HANDLER_ARGS) 2493e9c0cc15SPoul-Henning Kamp { 2494e9c0cc15SPoul-Henning Kamp struct xswdev xs; 2495dda4f960SKonstantin Belousov int error; 2496e9c0cc15SPoul-Henning Kamp 2497e9c0cc15SPoul-Henning Kamp if (arg2 != 1) /* name length */ 2498e9c0cc15SPoul-Henning Kamp return (EINVAL); 2499dda4f960SKonstantin Belousov error = swap_dev_info(*(int *)arg1, &xs, NULL, 0); 2500dda4f960SKonstantin Belousov if (error != 0) 2501dda4f960SKonstantin Belousov return (error); 2502e9c0cc15SPoul-Henning Kamp error = SYSCTL_OUT(req, &xs, sizeof(xs)); 2503e9c0cc15SPoul-Henning Kamp return (error); 2504e9c0cc15SPoul-Henning Kamp } 2505e9c0cc15SPoul-Henning Kamp 25068f60c087SPoul-Henning Kamp SYSCTL_INT(_vm, OID_AUTO, nswapdev, CTLFLAG_RD, &nswapdev, 0, 2507e9c0cc15SPoul-Henning Kamp "Number of swap devices"); 2508e9c0cc15SPoul-Henning Kamp SYSCTL_NODE(_vm, OID_AUTO, swap_info, CTLFLAG_RD, sysctl_vm_swap_info, 2509e9c0cc15SPoul-Henning Kamp "Swap statistics by device"); 2510ec38b344SPoul-Henning Kamp 2511ec38b344SPoul-Henning Kamp /* 25128eb5a1cdSKonstantin Belousov * vmspace_swap_count() - count the approximate swap usage in pages for a 2513ec38b344SPoul-Henning Kamp * vmspace. 2514ec38b344SPoul-Henning Kamp * 2515ec38b344SPoul-Henning Kamp * The map must be locked. 2516ec38b344SPoul-Henning Kamp * 25178eb5a1cdSKonstantin Belousov * Swap usage is determined by taking the proportional swap used by 2518ec38b344SPoul-Henning Kamp * VM objects backing the VM map. To make up for fractional losses, 2519ec38b344SPoul-Henning Kamp * if the VM object has any swap use at all the associated map entries 2520ec38b344SPoul-Henning Kamp * count for at least 1 swap page. 2521ec38b344SPoul-Henning Kamp */ 25222860553aSRebecca Cran long 2523ec38b344SPoul-Henning Kamp vmspace_swap_count(struct vmspace *vmspace) 2524ec38b344SPoul-Henning Kamp { 252565d8409cSRebecca Cran vm_map_t map; 2526ec38b344SPoul-Henning Kamp vm_map_entry_t cur; 252765d8409cSRebecca Cran vm_object_t object; 25282860553aSRebecca Cran long count, n; 252965d8409cSRebecca Cran 253065d8409cSRebecca Cran map = &vmspace->vm_map; 253165d8409cSRebecca Cran count = 0; 2532ec38b344SPoul-Henning Kamp 2533ec38b344SPoul-Henning Kamp for (cur = map->header.next; cur != &map->header; cur = cur->next) { 2534ec38b344SPoul-Henning Kamp if ((cur->eflags & MAP_ENTRY_IS_SUB_MAP) == 0 && 2535ec38b344SPoul-Henning Kamp (object = cur->object.vm_object) != NULL) { 253689f6b863SAttilio Rao VM_OBJECT_WLOCK(object); 2537ec38b344SPoul-Henning Kamp if (object->type == OBJT_SWAP && 2538ec38b344SPoul-Henning Kamp object->un_pager.swp.swp_bcount != 0) { 253965d8409cSRebecca Cran n = (cur->end - cur->start) / PAGE_SIZE; 2540ec38b344SPoul-Henning Kamp count += object->un_pager.swp.swp_bcount * 2541ec38b344SPoul-Henning Kamp SWAP_META_PAGES * n / object->size + 1; 2542ec38b344SPoul-Henning Kamp } 254389f6b863SAttilio Rao VM_OBJECT_WUNLOCK(object); 2544ec38b344SPoul-Henning Kamp } 2545ec38b344SPoul-Henning Kamp } 2546ec38b344SPoul-Henning Kamp return (count); 2547ec38b344SPoul-Henning Kamp } 2548dee34ca4SPoul-Henning Kamp 2549dee34ca4SPoul-Henning Kamp /* 2550dee34ca4SPoul-Henning Kamp * GEOM backend 2551dee34ca4SPoul-Henning Kamp * 2552dee34ca4SPoul-Henning Kamp * Swapping onto disk devices. 2553dee34ca4SPoul-Henning Kamp * 2554dee34ca4SPoul-Henning Kamp */ 2555dee34ca4SPoul-Henning Kamp 25565721c9c7SPoul-Henning Kamp static g_orphan_t swapgeom_orphan; 25575721c9c7SPoul-Henning Kamp 2558dee34ca4SPoul-Henning Kamp static struct g_class g_swap_class = { 2559dee34ca4SPoul-Henning Kamp .name = "SWAP", 25605721c9c7SPoul-Henning Kamp .version = G_VERSION, 25615721c9c7SPoul-Henning Kamp .orphan = swapgeom_orphan, 2562dee34ca4SPoul-Henning Kamp }; 2563dee34ca4SPoul-Henning Kamp 2564dee34ca4SPoul-Henning Kamp DECLARE_GEOM_CLASS(g_swap_class, g_class); 2565dee34ca4SPoul-Henning Kamp 2566dee34ca4SPoul-Henning Kamp 2567dee34ca4SPoul-Henning Kamp static void 25683398491bSAlexander Motin swapgeom_close_ev(void *arg, int flags) 25693398491bSAlexander Motin { 25703398491bSAlexander Motin struct g_consumer *cp; 25713398491bSAlexander Motin 25723398491bSAlexander Motin cp = arg; 25733398491bSAlexander Motin g_access(cp, -1, -1, 0); 25743398491bSAlexander Motin g_detach(cp); 25753398491bSAlexander Motin g_destroy_consumer(cp); 25763398491bSAlexander Motin } 25773398491bSAlexander Motin 25783398491bSAlexander Motin static void 2579dee34ca4SPoul-Henning Kamp swapgeom_done(struct bio *bp2) 2580dee34ca4SPoul-Henning Kamp { 25813398491bSAlexander Motin struct swdevt *sp; 2582dee34ca4SPoul-Henning Kamp struct buf *bp; 25833398491bSAlexander Motin struct g_consumer *cp; 2584dee34ca4SPoul-Henning Kamp 2585dee34ca4SPoul-Henning Kamp bp = bp2->bio_caller2; 25863398491bSAlexander Motin cp = bp2->bio_from; 2587c5d3d25eSPoul-Henning Kamp bp->b_ioflags = bp2->bio_flags; 2588dee34ca4SPoul-Henning Kamp if (bp2->bio_error) 2589dee34ca4SPoul-Henning Kamp bp->b_ioflags |= BIO_ERROR; 2590c5d3d25eSPoul-Henning Kamp bp->b_resid = bp->b_bcount - bp2->bio_completed; 2591c5d3d25eSPoul-Henning Kamp bp->b_error = bp2->bio_error; 2592dee34ca4SPoul-Henning Kamp bufdone(bp); 25933398491bSAlexander Motin mtx_lock(&sw_dev_mtx); 25940ada3afcSAlexander Motin if ((--cp->index) == 0 && cp->private) { 25950ada3afcSAlexander Motin if (g_post_event(swapgeom_close_ev, cp, M_NOWAIT, NULL) == 0) { 25963398491bSAlexander Motin sp = bp2->bio_caller1; 25973398491bSAlexander Motin sp->sw_id = NULL; 25983398491bSAlexander Motin } 25990ada3afcSAlexander Motin } 26003398491bSAlexander Motin mtx_unlock(&sw_dev_mtx); 2601dee34ca4SPoul-Henning Kamp g_destroy_bio(bp2); 2602dee34ca4SPoul-Henning Kamp } 2603dee34ca4SPoul-Henning Kamp 2604dee34ca4SPoul-Henning Kamp static void 2605dee34ca4SPoul-Henning Kamp swapgeom_strategy(struct buf *bp, struct swdevt *sp) 2606dee34ca4SPoul-Henning Kamp { 2607dee34ca4SPoul-Henning Kamp struct bio *bio; 2608dee34ca4SPoul-Henning Kamp struct g_consumer *cp; 2609dee34ca4SPoul-Henning Kamp 26103398491bSAlexander Motin mtx_lock(&sw_dev_mtx); 2611dee34ca4SPoul-Henning Kamp cp = sp->sw_id; 2612dee34ca4SPoul-Henning Kamp if (cp == NULL) { 26133398491bSAlexander Motin mtx_unlock(&sw_dev_mtx); 2614dee34ca4SPoul-Henning Kamp bp->b_error = ENXIO; 2615dee34ca4SPoul-Henning Kamp bp->b_ioflags |= BIO_ERROR; 2616dee34ca4SPoul-Henning Kamp bufdone(bp); 2617dee34ca4SPoul-Henning Kamp return; 2618dee34ca4SPoul-Henning Kamp } 26193398491bSAlexander Motin cp->index++; 26203398491bSAlexander Motin mtx_unlock(&sw_dev_mtx); 262111041003SKonstantin Belousov if (bp->b_iocmd == BIO_WRITE) 262211041003SKonstantin Belousov bio = g_new_bio(); 262311041003SKonstantin Belousov else 26244f8205e5SPoul-Henning Kamp bio = g_alloc_bio(); 26254f8205e5SPoul-Henning Kamp if (bio == NULL) { 26263e5b6861SPoul-Henning Kamp bp->b_error = ENOMEM; 26273e5b6861SPoul-Henning Kamp bp->b_ioflags |= BIO_ERROR; 26283e5b6861SPoul-Henning Kamp bufdone(bp); 26293e5b6861SPoul-Henning Kamp return; 26303e5b6861SPoul-Henning Kamp } 263111041003SKonstantin Belousov 26323398491bSAlexander Motin bio->bio_caller1 = sp; 2633dee34ca4SPoul-Henning Kamp bio->bio_caller2 = bp; 2634c5d3d25eSPoul-Henning Kamp bio->bio_cmd = bp->b_iocmd; 2635dee34ca4SPoul-Henning Kamp bio->bio_offset = (bp->b_blkno - sp->sw_first) * PAGE_SIZE; 2636dee34ca4SPoul-Henning Kamp bio->bio_length = bp->b_bcount; 2637dee34ca4SPoul-Henning Kamp bio->bio_done = swapgeom_done; 26382cc718a1SKonstantin Belousov if ((bp->b_flags & B_UNMAPPED) != 0) { 26392cc718a1SKonstantin Belousov bio->bio_ma = bp->b_pages; 26402cc718a1SKonstantin Belousov bio->bio_data = unmapped_buf; 26412cc718a1SKonstantin Belousov bio->bio_ma_offset = (vm_offset_t)bp->b_offset & PAGE_MASK; 26422cc718a1SKonstantin Belousov bio->bio_ma_n = bp->b_npages; 26432cc718a1SKonstantin Belousov bio->bio_flags |= BIO_UNMAPPED; 26442cc718a1SKonstantin Belousov } else { 26452cc718a1SKonstantin Belousov bio->bio_data = bp->b_data; 26462cc718a1SKonstantin Belousov bio->bio_ma = NULL; 26472cc718a1SKonstantin Belousov } 2648dee34ca4SPoul-Henning Kamp g_io_request(bio, cp); 2649dee34ca4SPoul-Henning Kamp return; 2650dee34ca4SPoul-Henning Kamp } 2651dee34ca4SPoul-Henning Kamp 2652dee34ca4SPoul-Henning Kamp static void 2653dee34ca4SPoul-Henning Kamp swapgeom_orphan(struct g_consumer *cp) 2654dee34ca4SPoul-Henning Kamp { 2655dee34ca4SPoul-Henning Kamp struct swdevt *sp; 26563398491bSAlexander Motin int destroy; 2657dee34ca4SPoul-Henning Kamp 2658dee34ca4SPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 26593398491bSAlexander Motin TAILQ_FOREACH(sp, &swtailq, sw_list) { 26603398491bSAlexander Motin if (sp->sw_id == cp) { 26618f12d83aSAlexander Motin sp->sw_flags |= SW_CLOSING; 26623398491bSAlexander Motin break; 2663dee34ca4SPoul-Henning Kamp } 26643398491bSAlexander Motin } 26653398491bSAlexander Motin cp->private = (void *)(uintptr_t)1; 26663398491bSAlexander Motin destroy = ((sp != NULL) && (cp->index == 0)); 26673398491bSAlexander Motin if (destroy) 26683398491bSAlexander Motin sp->sw_id = NULL; 26693398491bSAlexander Motin mtx_unlock(&sw_dev_mtx); 26703398491bSAlexander Motin if (destroy) 26713398491bSAlexander Motin swapgeom_close_ev(cp, 0); 2672dee34ca4SPoul-Henning Kamp } 2673dee34ca4SPoul-Henning Kamp 2674dee34ca4SPoul-Henning Kamp static void 2675dee34ca4SPoul-Henning Kamp swapgeom_close(struct thread *td, struct swdevt *sw) 2676dee34ca4SPoul-Henning Kamp { 26773398491bSAlexander Motin struct g_consumer *cp; 2678dee34ca4SPoul-Henning Kamp 26793398491bSAlexander Motin mtx_lock(&sw_dev_mtx); 26803398491bSAlexander Motin cp = sw->sw_id; 26813398491bSAlexander Motin sw->sw_id = NULL; 26823398491bSAlexander Motin mtx_unlock(&sw_dev_mtx); 2683dee34ca4SPoul-Henning Kamp /* XXX: direct call when Giant untangled */ 26843398491bSAlexander Motin if (cp != NULL) 26853398491bSAlexander Motin g_waitfor_event(swapgeom_close_ev, cp, M_WAITOK, NULL); 2686dee34ca4SPoul-Henning Kamp } 2687dee34ca4SPoul-Henning Kamp 2688dee34ca4SPoul-Henning Kamp 2689dee34ca4SPoul-Henning Kamp struct swh0h0 { 269089c9c53dSPoul-Henning Kamp struct cdev *dev; 2691dee34ca4SPoul-Henning Kamp struct vnode *vp; 2692dee34ca4SPoul-Henning Kamp int error; 2693dee34ca4SPoul-Henning Kamp }; 2694dee34ca4SPoul-Henning Kamp 2695dee34ca4SPoul-Henning Kamp static void 2696dee34ca4SPoul-Henning Kamp swapongeom_ev(void *arg, int flags) 2697dee34ca4SPoul-Henning Kamp { 2698dee34ca4SPoul-Henning Kamp struct swh0h0 *swh; 2699dee34ca4SPoul-Henning Kamp struct g_provider *pp; 2700dee34ca4SPoul-Henning Kamp struct g_consumer *cp; 2701dee34ca4SPoul-Henning Kamp static struct g_geom *gp; 2702dee34ca4SPoul-Henning Kamp struct swdevt *sp; 2703dee34ca4SPoul-Henning Kamp u_long nblks; 2704dee34ca4SPoul-Henning Kamp int error; 2705dee34ca4SPoul-Henning Kamp 2706dee34ca4SPoul-Henning Kamp swh = arg; 2707dee34ca4SPoul-Henning Kamp swh->error = 0; 2708dee34ca4SPoul-Henning Kamp pp = g_dev_getprovider(swh->dev); 2709dee34ca4SPoul-Henning Kamp if (pp == NULL) { 2710dee34ca4SPoul-Henning Kamp swh->error = ENODEV; 2711dee34ca4SPoul-Henning Kamp return; 2712dee34ca4SPoul-Henning Kamp } 2713dee34ca4SPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 2714dee34ca4SPoul-Henning Kamp TAILQ_FOREACH(sp, &swtailq, sw_list) { 2715dee34ca4SPoul-Henning Kamp cp = sp->sw_id; 2716dee34ca4SPoul-Henning Kamp if (cp != NULL && cp->provider == pp) { 2717dee34ca4SPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 2718dee34ca4SPoul-Henning Kamp swh->error = EBUSY; 2719dee34ca4SPoul-Henning Kamp return; 2720dee34ca4SPoul-Henning Kamp } 2721dee34ca4SPoul-Henning Kamp } 2722dee34ca4SPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 27235721c9c7SPoul-Henning Kamp if (gp == NULL) 272402c62349SJaakko Heinonen gp = g_new_geomf(&g_swap_class, "swap"); 2725dee34ca4SPoul-Henning Kamp cp = g_new_consumer(gp); 27263398491bSAlexander Motin cp->index = 0; /* Number of active I/Os. */ 27273398491bSAlexander Motin cp->private = NULL; /* Orphanization flag */ 2728dee34ca4SPoul-Henning Kamp g_attach(cp, pp); 2729afeb65e6SPoul-Henning Kamp /* 2730afeb65e6SPoul-Henning Kamp * XXX: Everytime you think you can improve the margin for 2731afeb65e6SPoul-Henning Kamp * footshooting, somebody depends on the ability to do so: 2732afeb65e6SPoul-Henning Kamp * savecore(8) wants to write to our swapdev so we cannot 2733afeb65e6SPoul-Henning Kamp * set an exclusive count :-( 2734afeb65e6SPoul-Henning Kamp */ 2735d2bae332SPoul-Henning Kamp error = g_access(cp, 1, 1, 0); 2736dee34ca4SPoul-Henning Kamp if (error) { 2737dee34ca4SPoul-Henning Kamp g_detach(cp); 2738dee34ca4SPoul-Henning Kamp g_destroy_consumer(cp); 2739dee34ca4SPoul-Henning Kamp swh->error = error; 2740dee34ca4SPoul-Henning Kamp return; 2741dee34ca4SPoul-Henning Kamp } 2742dee34ca4SPoul-Henning Kamp nblks = pp->mediasize / DEV_BSIZE; 2743dee34ca4SPoul-Henning Kamp swaponsomething(swh->vp, cp, nblks, swapgeom_strategy, 27442cc718a1SKonstantin Belousov swapgeom_close, dev2udev(swh->dev), 27452cc718a1SKonstantin Belousov (pp->flags & G_PF_ACCEPT_UNMAPPED) != 0 ? SW_UNMAPPED : 0); 2746dee34ca4SPoul-Henning Kamp swh->error = 0; 2747dee34ca4SPoul-Henning Kamp } 2748dee34ca4SPoul-Henning Kamp 2749dee34ca4SPoul-Henning Kamp static int 2750dee34ca4SPoul-Henning Kamp swapongeom(struct thread *td, struct vnode *vp) 2751dee34ca4SPoul-Henning Kamp { 2752dee34ca4SPoul-Henning Kamp int error; 2753dee34ca4SPoul-Henning Kamp struct swh0h0 swh; 2754dee34ca4SPoul-Henning Kamp 2755cb05b60aSAttilio Rao vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 2756dee34ca4SPoul-Henning Kamp 2757dee34ca4SPoul-Henning Kamp swh.dev = vp->v_rdev; 2758dee34ca4SPoul-Henning Kamp swh.vp = vp; 2759dee34ca4SPoul-Henning Kamp swh.error = 0; 2760dee34ca4SPoul-Henning Kamp /* XXX: direct call when Giant untangled */ 2761dee34ca4SPoul-Henning Kamp error = g_waitfor_event(swapongeom_ev, &swh, M_WAITOK, NULL); 2762dee34ca4SPoul-Henning Kamp if (!error) 2763dee34ca4SPoul-Henning Kamp error = swh.error; 276422db15c0SAttilio Rao VOP_UNLOCK(vp, 0); 2765dee34ca4SPoul-Henning Kamp return (error); 2766dee34ca4SPoul-Henning Kamp } 2767dee34ca4SPoul-Henning Kamp 2768dee34ca4SPoul-Henning Kamp /* 2769dee34ca4SPoul-Henning Kamp * VNODE backend 2770dee34ca4SPoul-Henning Kamp * 2771dee34ca4SPoul-Henning Kamp * This is used mainly for network filesystem (read: probably only tested 2772dee34ca4SPoul-Henning Kamp * with NFS) swapfiles. 2773dee34ca4SPoul-Henning Kamp * 2774dee34ca4SPoul-Henning Kamp */ 2775dee34ca4SPoul-Henning Kamp 2776dee34ca4SPoul-Henning Kamp static void 2777dee34ca4SPoul-Henning Kamp swapdev_strategy(struct buf *bp, struct swdevt *sp) 2778dee34ca4SPoul-Henning Kamp { 2779494eb176SPoul-Henning Kamp struct vnode *vp2; 2780dee34ca4SPoul-Henning Kamp 2781dee34ca4SPoul-Henning Kamp bp->b_blkno = ctodb(bp->b_blkno - sp->sw_first); 2782dee34ca4SPoul-Henning Kamp 2783dee34ca4SPoul-Henning Kamp vp2 = sp->sw_id; 2784dee34ca4SPoul-Henning Kamp vhold(vp2); 2785dee34ca4SPoul-Henning Kamp if (bp->b_iocmd == BIO_WRITE) { 27863cfc7651SOlivier Houchard if (bp->b_bufobj) 2787494eb176SPoul-Henning Kamp bufobj_wdrop(bp->b_bufobj); 2788a76d8f4eSPoul-Henning Kamp bufobj_wref(&vp2->v_bufobj); 2789dee34ca4SPoul-Henning Kamp } 27903cfc7651SOlivier Houchard if (bp->b_bufobj != &vp2->v_bufobj) 27913cfc7651SOlivier Houchard bp->b_bufobj = &vp2->v_bufobj; 2792dee34ca4SPoul-Henning Kamp bp->b_vp = vp2; 27932c18019fSPoul-Henning Kamp bp->b_iooffset = dbtob(bp->b_blkno); 2794b792bebeSPoul-Henning Kamp bstrategy(bp); 2795dee34ca4SPoul-Henning Kamp return; 2796dee34ca4SPoul-Henning Kamp } 2797dee34ca4SPoul-Henning Kamp 2798dee34ca4SPoul-Henning Kamp static void 2799dee34ca4SPoul-Henning Kamp swapdev_close(struct thread *td, struct swdevt *sp) 2800dee34ca4SPoul-Henning Kamp { 2801dee34ca4SPoul-Henning Kamp 2802dee34ca4SPoul-Henning Kamp VOP_CLOSE(sp->sw_vp, FREAD | FWRITE, td->td_ucred, td); 2803dee34ca4SPoul-Henning Kamp vrele(sp->sw_vp); 2804dee34ca4SPoul-Henning Kamp } 2805dee34ca4SPoul-Henning Kamp 2806dee34ca4SPoul-Henning Kamp 2807dee34ca4SPoul-Henning Kamp static int 2808dee34ca4SPoul-Henning Kamp swaponvp(struct thread *td, struct vnode *vp, u_long nblks) 2809dee34ca4SPoul-Henning Kamp { 2810dee34ca4SPoul-Henning Kamp struct swdevt *sp; 2811dee34ca4SPoul-Henning Kamp int error; 2812dee34ca4SPoul-Henning Kamp 2813dee34ca4SPoul-Henning Kamp if (nblks == 0) 2814dee34ca4SPoul-Henning Kamp return (ENXIO); 2815dee34ca4SPoul-Henning Kamp mtx_lock(&sw_dev_mtx); 2816dee34ca4SPoul-Henning Kamp TAILQ_FOREACH(sp, &swtailq, sw_list) { 2817dee34ca4SPoul-Henning Kamp if (sp->sw_id == vp) { 2818dee34ca4SPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 2819dee34ca4SPoul-Henning Kamp return (EBUSY); 2820dee34ca4SPoul-Henning Kamp } 2821dee34ca4SPoul-Henning Kamp } 2822dee34ca4SPoul-Henning Kamp mtx_unlock(&sw_dev_mtx); 2823dee34ca4SPoul-Henning Kamp 2824cb05b60aSAttilio Rao (void) vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 2825dee34ca4SPoul-Henning Kamp #ifdef MAC 282630d239bcSRobert Watson error = mac_system_check_swapon(td->td_ucred, vp); 2827dee34ca4SPoul-Henning Kamp if (error == 0) 2828dee34ca4SPoul-Henning Kamp #endif 28299e223287SKonstantin Belousov error = VOP_OPEN(vp, FREAD | FWRITE, td->td_ucred, td, NULL); 283022db15c0SAttilio Rao (void) VOP_UNLOCK(vp, 0); 2831dee34ca4SPoul-Henning Kamp if (error) 2832dee34ca4SPoul-Henning Kamp return (error); 2833dee34ca4SPoul-Henning Kamp 2834dee34ca4SPoul-Henning Kamp swaponsomething(vp, vp, nblks, swapdev_strategy, swapdev_close, 28352cc718a1SKonstantin Belousov NODEV, 0); 2836dee34ca4SPoul-Henning Kamp return (0); 2837dee34ca4SPoul-Henning Kamp } 2838