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
  20 uint64_t vn_generation;         /* vnode generation number */
  21 DEFINE_SPINLOCK(vnumber_lock);
  22
  23 /*
  24  * Dedicated vnode inactive/reclaim sync semaphores.
  25  * Prime number of hash buckets since address is used as the key.
  26  */
  27 #define NVSYNC                  37
  28 #define vptosync(v)             (&vsync[((unsigned long)v) % NVSYNC])
  29 STATIC wait_queue_head_t vsync[NVSYNC];
  30
  31 void
  32 vn_init(void)
  33 {
  34         int i;
  35
  36         for (i = 0; i < NVSYNC; i++)
  37                 init_waitqueue_head(&vsync[i]);
  38 }
  39
  40 void
  41 vn_iowait(
  42         struct vnode    *vp)
  43 {
  44         wait_queue_head_t *wq = vptosync(vp);
  45
  46         wait_event(*wq, (atomic_read(&vp->v_iocount) == 0));
  47 }
  48
  49 void
  50 vn_iowake(
  51         struct vnode    *vp)
  52 {
  53         if (atomic_dec_and_test(&vp->v_iocount))
  54                 wake_up(vptosync(vp));
  55 }
  56
  57 struct vnode *
  58 vn_initialize(
  59         struct inode    *inode)
  60 {
  61         struct vnode    *vp = LINVFS_GET_VP(inode);
  62
  63         XFS_STATS_INC(vn_active);
  64         XFS_STATS_INC(vn_alloc);
  65
  66         vp->v_flag = VMODIFIED;
  67         spinlock_init(&vp->v_lock, "v_lock");
  68
  69         spin_lock(&vnumber_lock);
  70         if (!++vn_generation)   /* v_number shouldn't be zero */
  71                 vn_generation++;
  72         vp->v_number = vn_generation;
  73         spin_unlock(&vnumber_lock);
  74
  75         ASSERT(VN_CACHED(vp) == 0);
  76
  77         /* Initialize the first behavior and the behavior chain head. */
  78         vn_bhv_head_init(VN_BHV_HEAD(vp), "vnode");
  79
  80         atomic_set(&vp->v_iocount, 0);
  81
  82 #ifdef  XFS_VNODE_TRACE
  83         vp->v_trace = ktrace_alloc(VNODE_TRACE_SIZE, KM_SLEEP);
  84 #endif  /* XFS_VNODE_TRACE */
  85
  86         vn_trace_exit(vp, __FUNCTION__, (inst_t *)__return_address);
  87         return vp;
  88 }
  89
  90 /*
  91  * Revalidate the Linux inode from the vattr.
  92  * Note: i_size _not_ updated; we must hold the inode
  93  * semaphore when doing that - callers responsibility.
  94  */
  95 void
  96 vn_revalidate_core(
  97         struct vnode    *vp,
  98         vattr_t         *vap)
  99 {
 100         struct inode    *inode = LINVFS_GET_IP(vp);
 101
 102         inode->i_mode       = vap->va_mode;
 103         inode->i_nlink      = vap->va_nlink;
 104         inode->i_uid        = vap->va_uid;
 105         inode->i_gid        = vap->va_gid;
 106         inode->i_blocks     = vap->va_nblocks;
 107         inode->i_mtime      = vap->va_mtime;
 108         inode->i_ctime      = vap->va_ctime;
 109         inode->i_blksize    = vap->va_blocksize;
 110         if (vap->va_xflags & XFS_XFLAG_IMMUTABLE)
 111                 inode->i_flags |= S_IMMUTABLE;
 112         else
 113                 inode->i_flags &= ~S_IMMUTABLE;
 114         if (vap->va_xflags & XFS_XFLAG_APPEND)
 115                 inode->i_flags |= S_APPEND;
 116         else
 117                 inode->i_flags &= ~S_APPEND;
 118         if (vap->va_xflags & XFS_XFLAG_SYNC)
 119                 inode->i_flags |= S_SYNC;
 120         else
 121                 inode->i_flags &= ~S_SYNC;
 122         if (vap->va_xflags & XFS_XFLAG_NOATIME)
 123                 inode->i_flags |= S_NOATIME;
 124         else
 125                 inode->i_flags &= ~S_NOATIME;
 126 }
 127
 128 /*
 129  * Revalidate the Linux inode from the vnode.
 130  */
 131 int
 132 __vn_revalidate(
 133         struct vnode    *vp,
 134         struct vattr    *vattr)
 135 {
 136         int             error;
 137
 138         vn_trace_entry(vp, __FUNCTION__, (inst_t *)__return_address);
 139         vattr->va_mask = XFS_AT_STAT | XFS_AT_XFLAGS;
 140         VOP_GETATTR(vp, vattr, 0, NULL, error);
 141         if (likely(!error)) {
 142                 vn_revalidate_core(vp, vattr);
 143                 VUNMODIFY(vp);
 144         }
 145         return -error;
 146 }
 147
 148 int
 149 vn_revalidate(
 150         struct vnode    *vp)
 151 {
 152         vattr_t         vattr;
 153
 154         return __vn_revalidate(vp, &vattr);
 155 }
 156
 157 /*
 158  * Add a reference to a referenced vnode.
 159  */
 160 struct vnode *
 161 vn_hold(
 162         struct vnode    *vp)
 163 {
 164         struct inode    *inode;
 165
 166         XFS_STATS_INC(vn_hold);
 167
 168         VN_LOCK(vp);
 169         inode = igrab(LINVFS_GET_IP(vp));
 170         ASSERT(inode);
 171         VN_UNLOCK(vp, 0);
 172
 173         return vp;
 174 }
 175
 176 #ifdef  XFS_VNODE_TRACE
 177
 178 #define KTRACE_ENTER(vp, vk, s, line, ra)                       \
 179         ktrace_enter(   (vp)->v_trace,                          \
 180 /*  0 */                (void *)(__psint_t)(vk),                \
 181 /*  1 */                (void *)(s),                            \
 182 /*  2 */                (void *)(__psint_t) line,               \
 183 /*  3 */                (void *)(__psint_t)(vn_count(vp)),      \
 184 /*  4 */                (void *)(ra),                           \
 185 /*  5 */                (void *)(__psunsigned_t)(vp)->v_flag,   \
 186 /*  6 */                (void *)(__psint_t)current_cpu(),       \
 187 /*  7 */                (void *)(__psint_t)current_pid(),       \
 188 /*  8 */                (void *)__return_address,               \
 189 /*  9 */                NULL, NULL, NULL, NULL, NULL, NULL, NULL)
 190
 191 /*
 192  * Vnode tracing code.
 193  */
 194 void
 195 vn_trace_entry(vnode_t *vp, const char *func, inst_t *ra)
 196 {
 197         KTRACE_ENTER(vp, VNODE_KTRACE_ENTRY, func, 0, ra);
 198 }
 199
 200 void
 201 vn_trace_exit(vnode_t *vp, const char *func, inst_t *ra)
 202 {
 203         KTRACE_ENTER(vp, VNODE_KTRACE_EXIT, func, 0, ra);
 204 }
 205
 206 void
 207 vn_trace_hold(vnode_t *vp, char *file, int line, inst_t *ra)
 208 {
 209         KTRACE_ENTER(vp, VNODE_KTRACE_HOLD, file, line, ra);
 210 }
 211
 212 void
 213 vn_trace_ref(vnode_t *vp, char *file, int line, inst_t *ra)
 214 {
 215         KTRACE_ENTER(vp, VNODE_KTRACE_REF, file, line, ra);
 216 }
 217
 218 void
 219 vn_trace_rele(vnode_t *vp, char *file, int line, inst_t *ra)
 220 {
 221         KTRACE_ENTER(vp, VNODE_KTRACE_RELE, file, line, ra);
 222 }
 223 #endif  /* XFS_VNODE_TRACE */