fs/xfs/linux-2.6/xfs_vnode.c

   1 /*
   2  * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #include "xfs.h"
  19 #include "xfs_vnodeops.h"
  20 #include "xfs_bmap_btree.h"
  21 #include "xfs_inode.h"
  22
  23 /*
  24  * And this gunk is needed for xfs_mount.h"
  25  */
  26 #include "xfs_log.h"
  27 #include "xfs_trans.h"
  28 #include "xfs_sb.h"
  29 #include "xfs_dmapi.h"
  30 #include "xfs_inum.h"
  31 #include "xfs_ag.h"
  32 #include "xfs_mount.h"
  33
  34 uint64_t vn_generation;         /* vnode generation number */
  35 DEFINE_SPINLOCK(vnumber_lock);
  36
  37 /*
  38  * Dedicated vnode inactive/reclaim sync semaphores.
  39  * Prime number of hash buckets since address is used as the key.
  40  */
  41 #define NVSYNC                  37
  42 #define vptosync(v)             (&vsync[((unsigned long)v) % NVSYNC])
  43 static wait_queue_head_t vsync[NVSYNC];
  44
  45 void
  46 vn_init(void)
  47 {
  48         int i;
  49
  50         for (i = 0; i < NVSYNC; i++)
  51                 init_waitqueue_head(&vsync[i]);
  52 }
  53
  54 void
  55 vn_iowait(
  56         xfs_inode_t     *ip)
  57 {
  58         wait_queue_head_t *wq = vptosync(ip);
  59
  60         wait_event(*wq, (atomic_read(&ip->i_iocount) == 0));
  61 }
  62
  63 void
  64 vn_iowake(
  65         xfs_inode_t     *ip)
  66 {
  67         if (atomic_dec_and_test(&ip->i_iocount))
  68                 wake_up(vptosync(ip));
  69 }
  70
  71 /*
  72  * Volume managers supporting multiple paths can send back ENODEV when the
  73  * final path disappears.  In this case continuing to fill the page cache
  74  * with dirty data which cannot be written out is evil, so prevent that.
  75  */
  76 void
  77 vn_ioerror(
  78         xfs_inode_t     *ip,
  79         int             error,
  80         char            *f,
  81         int             l)
  82 {
  83         bhv_vfs_t       *vfsp = XFS_MTOVFS(ip->i_mount);
  84
  85         if (unlikely(error == -ENODEV))
  86                 bhv_vfs_force_shutdown(vfsp, SHUTDOWN_DEVICE_REQ, f, l);
  87 }
  88
  89 bhv_vnode_t *
  90 vn_initialize(
  91         struct inode    *inode)
  92 {
  93         bhv_vnode_t     *vp = vn_from_inode(inode);
  94
  95         XFS_STATS_INC(vn_active);
  96         XFS_STATS_INC(vn_alloc);
  97
  98         spin_lock(&vnumber_lock);
  99         if (!++vn_generation)   /* v_number shouldn't be zero */
 100                 vn_generation++;
 101         vp->v_number = vn_generation;
 102         spin_unlock(&vnumber_lock);
 103
 104         ASSERT(VN_CACHED(vp) == 0);
 105
 106 #ifdef  XFS_VNODE_TRACE
 107         vp->v_trace = ktrace_alloc(VNODE_TRACE_SIZE, KM_SLEEP);
 108 #endif  /* XFS_VNODE_TRACE */
 109
 110         vn_trace_exit(vp, __FUNCTION__, (inst_t *)__return_address);
 111         return vp;
 112 }
 113
 114 /*
 115  * Revalidate the Linux inode from the vattr.
 116  * Note: i_size _not_ updated; we must hold the inode
 117  * semaphore when doing that - callers responsibility.
 118  */
 119 void
 120 vn_revalidate_core(
 121         bhv_vnode_t     *vp,
 122         bhv_vattr_t     *vap)
 123 {
 124         struct inode    *inode = vn_to_inode(vp);
 125
 126         inode->i_mode       = vap->va_mode;
 127         inode->i_nlink      = vap->va_nlink;
 128         inode->i_uid        = vap->va_uid;
 129         inode->i_gid        = vap->va_gid;
 130         inode->i_blocks     = vap->va_nblocks;
 131         inode->i_mtime      = vap->va_mtime;
 132         inode->i_ctime      = vap->va_ctime;
 133         if (vap->va_xflags & XFS_XFLAG_IMMUTABLE)
 134                 inode->i_flags |= S_IMMUTABLE;
 135         else
 136                 inode->i_flags &= ~S_IMMUTABLE;
 137         if (vap->va_xflags & XFS_XFLAG_APPEND)
 138                 inode->i_flags |= S_APPEND;
 139         else
 140                 inode->i_flags &= ~S_APPEND;
 141         if (vap->va_xflags & XFS_XFLAG_SYNC)
 142                 inode->i_flags |= S_SYNC;
 143         else
 144                 inode->i_flags &= ~S_SYNC;
 145         if (vap->va_xflags & XFS_XFLAG_NOATIME)
 146                 inode->i_flags |= S_NOATIME;
 147         else
 148                 inode->i_flags &= ~S_NOATIME;
 149 }
 150
 151 /*
 152  * Revalidate the Linux inode from the vnode.
 153  */
 154 int
 155 __vn_revalidate(
 156         bhv_vnode_t     *vp,
 157         bhv_vattr_t     *vattr)
 158 {
 159         int             error;
 160
 161         vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
 162         vattr->va_mask = XFS_AT_STAT | XFS_AT_XFLAGS;
 163         error = xfs_getattr(xfs_vtoi(vp), vattr, 0);
 164         if (likely(!error)) {
 165                 vn_revalidate_core(vp, vattr);
 166                 xfs_iflags_clear(xfs_vtoi(vp), XFS_IMODIFIED);
 167         }
 168         return -error;
 169 }
 170
 171 int
 172 vn_revalidate(
 173         bhv_vnode_t     *vp)
 174 {
 175         bhv_vattr_t     vattr;
 176
 177         return __vn_revalidate(vp, &vattr);
 178 }
 179
 180 /*
 181  * Add a reference to a referenced vnode.
 182  */
 183 bhv_vnode_t *
 184 vn_hold(
 185         bhv_vnode_t     *vp)
 186 {
 187         struct inode    *inode;
 188
 189         XFS_STATS_INC(vn_hold);
 190
 191         inode = igrab(vn_to_inode(vp));
 192         ASSERT(inode);
 193
 194         return vp;
 195 }
 196
 197 #ifdef  XFS_VNODE_TRACE
 198
 199 #define KTRACE_ENTER(vp, vk, s, line, ra)                       \
 200         ktrace_enter(   (vp)->v_trace,                          \
 201 /*  0 */                (void *)(__psint_t)(vk),                \
 202 /*  1 */                (void *)(s),                            \
 203 /*  2 */                (void *)(__psint_t) line,               \
 204 /*  3 */                (void *)(__psint_t)(vn_count(vp)),      \
 205 /*  4 */                (void *)(ra),                           \
 206 /*  5 */                NULL,                                   \
 207 /*  6 */                (void *)(__psint_t)current_cpu(),       \
 208 /*  7 */                (void *)(__psint_t)current_pid(),       \
 209 /*  8 */                (void *)__return_address,               \
 210 /*  9 */                NULL, NULL, NULL, NULL, NULL, NULL, NULL)
 211
 212 /*
 213  * Vnode tracing code.
 214  */
 215 void
 216 vn_trace_entry(bhv_vnode_t *vp, const char *func, inst_t *ra)
 217 {
 218         KTRACE_ENTER(vp, VNODE_KTRACE_ENTRY, func, 0, ra);
 219 }
 220
 221 void
 222 vn_trace_exit(bhv_vnode_t *vp, const char *func, inst_t *ra)
 223 {
 224         KTRACE_ENTER(vp, VNODE_KTRACE_EXIT, func, 0, ra);
 225 }
 226
 227 void
 228 vn_trace_hold(bhv_vnode_t *vp, char *file, int line, inst_t *ra)
 229 {
 230         KTRACE_ENTER(vp, VNODE_KTRACE_HOLD, file, line, ra);
 231 }
 232
 233 void
 234 vn_trace_ref(bhv_vnode_t *vp, char *file, int line, inst_t *ra)
 235 {
 236         KTRACE_ENTER(vp, VNODE_KTRACE_REF, file, line, ra);
 237 }
 238
 239 void
 240 vn_trace_rele(bhv_vnode_t *vp, char *file, int line, inst_t *ra)
 241 {
 242         KTRACE_ENTER(vp, VNODE_KTRACE_RELE, file, line, ra);
 243 }
 244 #endif  /* XFS_VNODE_TRACE */