1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2003 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #include <mdb/mdb_modapi.h> 28 #include <sys/buf.h> 29 #include <sys/var.h> 30 #include <vm/page.h> 31 32 #include "bio.h" 33 34 typedef struct buf_walk { 35 uintptr_t bw_hbufbase; /* Base address of hbuf buckets */ 36 struct hbuf *bw_hbufs; /* Snapshot of hbuf buckets */ 37 size_t bw_nhbufs; /* Number of hbuf buckets */ 38 size_t bw_hbufi; /* Current hbuf index */ 39 buf_t *bw_bufp; /* Current buffer */ 40 } buf_walk_t; 41 42 int 43 buf_walk_init(mdb_walk_state_t *wsp) 44 { 45 struct hbuf *hbufs; 46 struct var v; 47 48 uintptr_t hbuf_addr; 49 size_t nbytes; 50 51 buf_walk_t *bwp; 52 53 if (wsp->walk_addr != 0) { 54 mdb_warn("only global buf walk supported\n"); 55 return (WALK_ERR); 56 } 57 58 if (mdb_readvar(&v, "v") == -1) { 59 mdb_warn("failed to read var struct"); 60 return (WALK_ERR); 61 } 62 63 if (mdb_readvar(&hbuf_addr, "hbuf") == -1) { 64 mdb_warn("failed to read hbuf pointer"); 65 return (WALK_ERR); 66 } 67 68 nbytes = sizeof (struct hbuf) * v.v_hbuf; 69 hbufs = mdb_alloc(nbytes, UM_SLEEP); 70 71 if (mdb_vread(hbufs, nbytes, hbuf_addr) != nbytes) { 72 mdb_warn("failed to read hbufs"); 73 mdb_free(hbufs, nbytes); 74 return (WALK_ERR); 75 } 76 77 bwp = mdb_alloc(sizeof (buf_walk_t), UM_SLEEP); 78 79 bwp->bw_hbufbase = hbuf_addr; 80 bwp->bw_hbufs = hbufs; 81 bwp->bw_nhbufs = v.v_hbuf; 82 bwp->bw_hbufi = 0; 83 bwp->bw_bufp = mdb_alloc(sizeof (buf_t), UM_SLEEP); 84 85 wsp->walk_addr = (uintptr_t)hbufs[0].b_forw; 86 wsp->walk_data = bwp; 87 88 return (WALK_NEXT); 89 } 90 91 int 92 buf_walk_step(mdb_walk_state_t *wsp) 93 { 94 buf_walk_t *bwp = wsp->walk_data; 95 uintptr_t addr; 96 97 /* 98 * If the next buf_t address we want is NULL or points back at the 99 * hbuf itself, advance to the next hash bucket. When we reach 100 * bw_nhbufs, we're done. 101 */ 102 while (wsp->walk_addr == 0 || wsp->walk_addr == (bwp->bw_hbufbase + 103 bwp->bw_hbufi * sizeof (struct hbuf))) { 104 105 if (++bwp->bw_hbufi == bwp->bw_nhbufs) 106 return (WALK_DONE); 107 108 wsp->walk_addr = (uintptr_t) 109 bwp->bw_hbufs[bwp->bw_hbufi].b_forw; 110 } 111 112 /* 113 * When we have a buf_t address, read the buffer and invoke our 114 * walk callback. We keep the next buf_t address in wsp->walk_addr. 115 */ 116 addr = wsp->walk_addr; 117 (void) mdb_vread(bwp->bw_bufp, sizeof (buf_t), addr); 118 wsp->walk_addr = (uintptr_t)bwp->bw_bufp->b_forw; 119 120 return (wsp->walk_callback(addr, bwp->bw_bufp, wsp->walk_cbdata)); 121 } 122 123 void 124 buf_walk_fini(mdb_walk_state_t *wsp) 125 { 126 buf_walk_t *bwp = wsp->walk_data; 127 128 mdb_free(bwp->bw_hbufs, sizeof (struct hbuf) * bwp->bw_nhbufs); 129 mdb_free(bwp->bw_bufp, sizeof (buf_t)); 130 mdb_free(bwp, sizeof (buf_walk_t)); 131 } 132 133 /*ARGSUSED*/ 134 int 135 bufpagefind(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) 136 { 137 uintptr_t b_addr = addr; 138 uintptr_t arg; 139 140 page_t p; 141 buf_t b; 142 143 if (argc != 1) 144 return (DCMD_USAGE); 145 146 if (argv->a_type == MDB_TYPE_IMMEDIATE) 147 arg = (uintptr_t)argv->a_un.a_val; 148 else 149 arg = (uintptr_t)mdb_strtoull(argv->a_un.a_str); 150 151 if (mdb_vread(&b, sizeof (buf_t), b_addr) == -1) 152 return (DCMD_ERR); 153 154 for (addr = (uintptr_t)b.b_pages; addr != 0; 155 addr = (uintptr_t)p.p_next) { 156 157 if (addr == arg) { 158 mdb_printf("buf %p has page %p on b_pages list\n", 159 b_addr, addr); 160 break; 161 } 162 163 if (mdb_vread(&p, sizeof (page_t), addr) == -1) 164 return (DCMD_ERR); 165 } 166 167 return (DCMD_OK); 168 } 169