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-rw-r--r--fs/xfs/xfs_iget.c455
1 files changed, 0 insertions, 455 deletions
diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c
deleted file mode 100644
index ea9a5fa49a48..000000000000
--- a/fs/xfs/xfs_iget.c
+++ /dev/null
@@ -1,455 +0,0 @@
-/*
- * Copyright (c) 2000-2005 Silicon Graphics, Inc.
- * All Rights Reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it would be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-#include "xfs.h"
-#include "xfs_fs.h"
-#include "xfs_types.h"
-#include "xfs_acl.h"
-#include "xfs_log.h"
-#include "xfs_inum.h"
-#include "xfs_trans.h"
-#include "xfs_sb.h"
-#include "xfs_ag.h"
-#include "xfs_mount.h"
-#include "xfs_bmap_btree.h"
-#include "xfs_alloc_btree.h"
-#include "xfs_ialloc_btree.h"
-#include "xfs_dinode.h"
-#include "xfs_inode.h"
-#include "xfs_btree.h"
-#include "xfs_ialloc.h"
-#include "xfs_quota.h"
-#include "xfs_utils.h"
-#include "xfs_trans_priv.h"
-#include "xfs_inode_item.h"
-#include "xfs_bmap.h"
-#include "xfs_trace.h"
-#include "xfs_icache.h"
-
-
-/*
- * Allocate and initialise an xfs_inode.
- */
-STATIC struct xfs_inode *
-xfs_inode_alloc(
- struct xfs_mount *mp,
- xfs_ino_t ino)
-{
- struct xfs_inode *ip;
-
- /*
- * if this didn't occur in transactions, we could use
- * KM_MAYFAIL and return NULL here on ENOMEM. Set the
- * code up to do this anyway.
- */
- ip = kmem_zone_alloc(xfs_inode_zone, KM_SLEEP);
- if (!ip)
- return NULL;
- if (inode_init_always(mp->m_super, VFS_I(ip))) {
- kmem_zone_free(xfs_inode_zone, ip);
- return NULL;
- }
-
- ASSERT(atomic_read(&ip->i_pincount) == 0);
- ASSERT(!spin_is_locked(&ip->i_flags_lock));
- ASSERT(!xfs_isiflocked(ip));
- ASSERT(ip->i_ino == 0);
-
- mrlock_init(&ip->i_iolock, MRLOCK_BARRIER, "xfsio", ip->i_ino);
-
- /* initialise the xfs inode */
- ip->i_ino = ino;
- ip->i_mount = mp;
- memset(&ip->i_imap, 0, sizeof(struct xfs_imap));
- ip->i_afp = NULL;
- memset(&ip->i_df, 0, sizeof(xfs_ifork_t));
- ip->i_flags = 0;
- ip->i_delayed_blks = 0;
- memset(&ip->i_d, 0, sizeof(xfs_icdinode_t));
-
- return ip;
-}
-
-STATIC void
-xfs_inode_free_callback(
- struct rcu_head *head)
-{
- struct inode *inode = container_of(head, struct inode, i_rcu);
- struct xfs_inode *ip = XFS_I(inode);
-
- kmem_zone_free(xfs_inode_zone, ip);
-}
-
-void
-xfs_inode_free(
- struct xfs_inode *ip)
-{
- switch (ip->i_d.di_mode & S_IFMT) {
- case S_IFREG:
- case S_IFDIR:
- case S_IFLNK:
- xfs_idestroy_fork(ip, XFS_DATA_FORK);
- break;
- }
-
- if (ip->i_afp)
- xfs_idestroy_fork(ip, XFS_ATTR_FORK);
-
- if (ip->i_itemp) {
- ASSERT(!(ip->i_itemp->ili_item.li_flags & XFS_LI_IN_AIL));
- xfs_inode_item_destroy(ip);
- ip->i_itemp = NULL;
- }
-
- /* asserts to verify all state is correct here */
- ASSERT(atomic_read(&ip->i_pincount) == 0);
- ASSERT(!spin_is_locked(&ip->i_flags_lock));
- ASSERT(!xfs_isiflocked(ip));
-
- /*
- * Because we use RCU freeing we need to ensure the inode always
- * appears to be reclaimed with an invalid inode number when in the
- * free state. The ip->i_flags_lock provides the barrier against lookup
- * races.
- */
- spin_lock(&ip->i_flags_lock);
- ip->i_flags = XFS_IRECLAIM;
- ip->i_ino = 0;
- spin_unlock(&ip->i_flags_lock);
-
- call_rcu(&VFS_I(ip)->i_rcu, xfs_inode_free_callback);
-}
-
-/*
- * Check the validity of the inode we just found it the cache
- */
-static int
-xfs_iget_cache_hit(
- struct xfs_perag *pag,
- struct xfs_inode *ip,
- xfs_ino_t ino,
- int flags,
- int lock_flags) __releases(RCU)
-{
- struct inode *inode = VFS_I(ip);
- struct xfs_mount *mp = ip->i_mount;
- int error;
-
- /*
- * check for re-use of an inode within an RCU grace period due to the
- * radix tree nodes not being updated yet. We monitor for this by
- * setting the inode number to zero before freeing the inode structure.
- * If the inode has been reallocated and set up, then the inode number
- * will not match, so check for that, too.
- */
- spin_lock(&ip->i_flags_lock);
- if (ip->i_ino != ino) {
- trace_xfs_iget_skip(ip);
- XFS_STATS_INC(xs_ig_frecycle);
- error = EAGAIN;
- goto out_error;
- }
-
-
- /*
- * If we are racing with another cache hit that is currently
- * instantiating this inode or currently recycling it out of
- * reclaimabe state, wait for the initialisation to complete
- * before continuing.
- *
- * XXX(hch): eventually we should do something equivalent to
- * wait_on_inode to wait for these flags to be cleared
- * instead of polling for it.
- */
- if (ip->i_flags & (XFS_INEW|XFS_IRECLAIM)) {
- trace_xfs_iget_skip(ip);
- XFS_STATS_INC(xs_ig_frecycle);
- error = EAGAIN;
- goto out_error;
- }
-
- /*
- * If lookup is racing with unlink return an error immediately.
- */
- if (ip->i_d.di_mode == 0 && !(flags & XFS_IGET_CREATE)) {
- error = ENOENT;
- goto out_error;
- }
-
- /*
- * If IRECLAIMABLE is set, we've torn down the VFS inode already.
- * Need to carefully get it back into useable state.
- */
- if (ip->i_flags & XFS_IRECLAIMABLE) {
- trace_xfs_iget_reclaim(ip);
-
- /*
- * We need to set XFS_IRECLAIM to prevent xfs_reclaim_inode
- * from stomping over us while we recycle the inode. We can't
- * clear the radix tree reclaimable tag yet as it requires
- * pag_ici_lock to be held exclusive.
- */
- ip->i_flags |= XFS_IRECLAIM;
-
- spin_unlock(&ip->i_flags_lock);
- rcu_read_unlock();
-
- error = -inode_init_always(mp->m_super, inode);
- if (error) {
- /*
- * Re-initializing the inode failed, and we are in deep
- * trouble. Try to re-add it to the reclaim list.
- */
- rcu_read_lock();
- spin_lock(&ip->i_flags_lock);
-
- ip->i_flags &= ~(XFS_INEW | XFS_IRECLAIM);
- ASSERT(ip->i_flags & XFS_IRECLAIMABLE);
- trace_xfs_iget_reclaim_fail(ip);
- goto out_error;
- }
-
- spin_lock(&pag->pag_ici_lock);
- spin_lock(&ip->i_flags_lock);
-
- /*
- * Clear the per-lifetime state in the inode as we are now
- * effectively a new inode and need to return to the initial
- * state before reuse occurs.
- */
- ip->i_flags &= ~XFS_IRECLAIM_RESET_FLAGS;
- ip->i_flags |= XFS_INEW;
- __xfs_inode_clear_reclaim_tag(mp, pag, ip);
- inode->i_state = I_NEW;
-
- ASSERT(!rwsem_is_locked(&ip->i_iolock.mr_lock));
- mrlock_init(&ip->i_iolock, MRLOCK_BARRIER, "xfsio", ip->i_ino);
-
- spin_unlock(&ip->i_flags_lock);
- spin_unlock(&pag->pag_ici_lock);
- } else {
- /* If the VFS inode is being torn down, pause and try again. */
- if (!igrab(inode)) {
- trace_xfs_iget_skip(ip);
- error = EAGAIN;
- goto out_error;
- }
-
- /* We've got a live one. */
- spin_unlock(&ip->i_flags_lock);
- rcu_read_unlock();
- trace_xfs_iget_hit(ip);
- }
-
- if (lock_flags != 0)
- xfs_ilock(ip, lock_flags);
-
- xfs_iflags_clear(ip, XFS_ISTALE | XFS_IDONTCACHE);
- XFS_STATS_INC(xs_ig_found);
-
- return 0;
-
-out_error:
- spin_unlock(&ip->i_flags_lock);
- rcu_read_unlock();
- return error;
-}
-
-
-static int
-xfs_iget_cache_miss(
- struct xfs_mount *mp,
- struct xfs_perag *pag,
- xfs_trans_t *tp,
- xfs_ino_t ino,
- struct xfs_inode **ipp,
- int flags,
- int lock_flags)
-{
- struct xfs_inode *ip;
- int error;
- xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ino);
- int iflags;
-
- ip = xfs_inode_alloc(mp, ino);
- if (!ip)
- return ENOMEM;
-
- error = xfs_iread(mp, tp, ip, flags);
- if (error)
- goto out_destroy;
-
- trace_xfs_iget_miss(ip);
-
- if ((ip->i_d.di_mode == 0) && !(flags & XFS_IGET_CREATE)) {
- error = ENOENT;
- goto out_destroy;
- }
-
- /*
- * Preload the radix tree so we can insert safely under the
- * write spinlock. Note that we cannot sleep inside the preload
- * region. Since we can be called from transaction context, don't
- * recurse into the file system.
- */
- if (radix_tree_preload(GFP_NOFS)) {
- error = EAGAIN;
- goto out_destroy;
- }
-
- /*
- * Because the inode hasn't been added to the radix-tree yet it can't
- * be found by another thread, so we can do the non-sleeping lock here.
- */
- if (lock_flags) {
- if (!xfs_ilock_nowait(ip, lock_flags))
- BUG();
- }
-
- /*
- * These values must be set before inserting the inode into the radix
- * tree as the moment it is inserted a concurrent lookup (allowed by the
- * RCU locking mechanism) can find it and that lookup must see that this
- * is an inode currently under construction (i.e. that XFS_INEW is set).
- * The ip->i_flags_lock that protects the XFS_INEW flag forms the
- * memory barrier that ensures this detection works correctly at lookup
- * time.
- */
- iflags = XFS_INEW;
- if (flags & XFS_IGET_DONTCACHE)
- iflags |= XFS_IDONTCACHE;
- ip->i_udquot = ip->i_gdquot = NULL;
- xfs_iflags_set(ip, iflags);
-
- /* insert the new inode */
- spin_lock(&pag->pag_ici_lock);
- error = radix_tree_insert(&pag->pag_ici_root, agino, ip);
- if (unlikely(error)) {
- WARN_ON(error != -EEXIST);
- XFS_STATS_INC(xs_ig_dup);
- error = EAGAIN;
- goto out_preload_end;
- }
- spin_unlock(&pag->pag_ici_lock);
- radix_tree_preload_end();
-
- *ipp = ip;
- return 0;
-
-out_preload_end:
- spin_unlock(&pag->pag_ici_lock);
- radix_tree_preload_end();
- if (lock_flags)
- xfs_iunlock(ip, lock_flags);
-out_destroy:
- __destroy_inode(VFS_I(ip));
- xfs_inode_free(ip);
- return error;
-}
-
-/*
- * Look up an inode by number in the given file system.
- * The inode is looked up in the cache held in each AG.
- * If the inode is found in the cache, initialise the vfs inode
- * if necessary.
- *
- * If it is not in core, read it in from the file system's device,
- * add it to the cache and initialise the vfs inode.
- *
- * The inode is locked according to the value of the lock_flags parameter.
- * This flag parameter indicates how and if the inode's IO lock and inode lock
- * should be taken.
- *
- * mp -- the mount point structure for the current file system. It points
- * to the inode hash table.
- * tp -- a pointer to the current transaction if there is one. This is
- * simply passed through to the xfs_iread() call.
- * ino -- the number of the inode desired. This is the unique identifier
- * within the file system for the inode being requested.
- * lock_flags -- flags indicating how to lock the inode. See the comment
- * for xfs_ilock() for a list of valid values.
- */
-int
-xfs_iget(
- xfs_mount_t *mp,
- xfs_trans_t *tp,
- xfs_ino_t ino,
- uint flags,
- uint lock_flags,
- xfs_inode_t **ipp)
-{
- xfs_inode_t *ip;
- int error;
- xfs_perag_t *pag;
- xfs_agino_t agino;
-
- /*
- * xfs_reclaim_inode() uses the ILOCK to ensure an inode
- * doesn't get freed while it's being referenced during a
- * radix tree traversal here. It assumes this function
- * aqcuires only the ILOCK (and therefore it has no need to
- * involve the IOLOCK in this synchronization).
- */
- ASSERT((lock_flags & (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED)) == 0);
-
- /* reject inode numbers outside existing AGs */
- if (!ino || XFS_INO_TO_AGNO(mp, ino) >= mp->m_sb.sb_agcount)
- return EINVAL;
-
- /* get the perag structure and ensure that it's inode capable */
- pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ino));
- agino = XFS_INO_TO_AGINO(mp, ino);
-
-again:
- error = 0;
- rcu_read_lock();
- ip = radix_tree_lookup(&pag->pag_ici_root, agino);
-
- if (ip) {
- error = xfs_iget_cache_hit(pag, ip, ino, flags, lock_flags);
- if (error)
- goto out_error_or_again;
- } else {
- rcu_read_unlock();
- XFS_STATS_INC(xs_ig_missed);
-
- error = xfs_iget_cache_miss(mp, pag, tp, ino, &ip,
- flags, lock_flags);
- if (error)
- goto out_error_or_again;
- }
- xfs_perag_put(pag);
-
- *ipp = ip;
-
- /*
- * If we have a real type for an on-disk inode, we can set ops(&unlock)
- * now. If it's a new inode being created, xfs_ialloc will handle it.
- */
- if (xfs_iflags_test(ip, XFS_INEW) && ip->i_d.di_mode != 0)
- xfs_setup_inode(ip);
- return 0;
-
-out_error_or_again:
- if (error == EAGAIN) {
- delay(1);
- goto again;
- }
- xfs_perag_put(pag);
- return error;
-}
-
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-10 13:51:05 +0000