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-rw-r--r--fs/bfs/inode.c2
-rw-r--r--fs/bio.c20
-rw-r--r--fs/dcache.c85
-rw-r--r--fs/efs/inode.c2
-rw-r--r--fs/gfs2/glock.c8
-rw-r--r--fs/gfs2/glops.c18
-rw-r--r--fs/gfs2/inode.c6
-rw-r--r--fs/gfs2/main.c2
-rw-r--r--fs/hugetlbfs/inode.c8
-rw-r--r--fs/jfs/jfs_dtree.c31
-rw-r--r--fs/namei.c102
-rw-r--r--fs/namespace.c2
-rw-r--r--fs/nilfs2/segbuf.c5
-rw-r--r--fs/ocfs2/super.c2
-rw-r--r--fs/proc/fd.c2
-rw-r--r--fs/proc/generic.c2
-rw-r--r--fs/proc/root.c4
17 files changed, 194 insertions, 107 deletions
diff --git a/fs/bfs/inode.c b/fs/bfs/inode.c
index 5e376bb93419..8defc6b3f9a2 100644
--- a/fs/bfs/inode.c
+++ b/fs/bfs/inode.c
@@ -40,7 +40,7 @@ struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
int block, off;
inode = iget_locked(sb, ino);
- if (IS_ERR(inode))
+ if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
diff --git a/fs/bio.c b/fs/bio.c
index 94bbc04dba77..c5eae7251490 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -1045,12 +1045,22 @@ static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs,
int bio_uncopy_user(struct bio *bio)
{
struct bio_map_data *bmd = bio->bi_private;
- int ret = 0;
+ struct bio_vec *bvec;
+ int ret = 0, i;
- if (!bio_flagged(bio, BIO_NULL_MAPPED))
- ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs,
- bmd->nr_sgvecs, bio_data_dir(bio) == READ,
- 0, bmd->is_our_pages);
+ if (!bio_flagged(bio, BIO_NULL_MAPPED)) {
+ /*
+ * if we're in a workqueue, the request is orphaned, so
+ * don't copy into a random user address space, just free.
+ */
+ if (current->mm)
+ ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs,
+ bmd->nr_sgvecs, bio_data_dir(bio) == READ,
+ 0, bmd->is_our_pages);
+ else if (bmd->is_our_pages)
+ bio_for_each_segment_all(bvec, bio, i)
+ __free_page(bvec->bv_page);
+ }
bio_free_map_data(bmd);
bio_put(bio);
return ret;
diff --git a/fs/dcache.c b/fs/dcache.c
index 87bdb5329c3c..96655f4f4574 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -229,7 +229,7 @@ static void __d_free(struct rcu_head *head)
*/
static void d_free(struct dentry *dentry)
{
- BUG_ON(dentry->d_count);
+ BUG_ON(dentry->d_lockref.count);
this_cpu_dec(nr_dentry);
if (dentry->d_op && dentry->d_op->d_release)
dentry->d_op->d_release(dentry);
@@ -467,7 +467,7 @@ relock:
}
if (ref)
- dentry->d_count--;
+ dentry->d_lockref.count--;
/*
* inform the fs via d_prune that this dentry is about to be
* unhashed and destroyed.
@@ -513,15 +513,10 @@ void dput(struct dentry *dentry)
return;
repeat:
- if (dentry->d_count == 1)
+ if (dentry->d_lockref.count == 1)
might_sleep();
- spin_lock(&dentry->d_lock);
- BUG_ON(!dentry->d_count);
- if (dentry->d_count > 1) {
- dentry->d_count--;
- spin_unlock(&dentry->d_lock);
+ if (lockref_put_or_lock(&dentry->d_lockref))
return;
- }
if (dentry->d_flags & DCACHE_OP_DELETE) {
if (dentry->d_op->d_delete(dentry))
@@ -535,7 +530,7 @@ repeat:
dentry->d_flags |= DCACHE_REFERENCED;
dentry_lru_add(dentry);
- dentry->d_count--;
+ dentry->d_lockref.count--;
spin_unlock(&dentry->d_lock);
return;
@@ -590,7 +585,7 @@ int d_invalidate(struct dentry * dentry)
* We also need to leave mountpoints alone,
* directory or not.
*/
- if (dentry->d_count > 1 && dentry->d_inode) {
+ if (dentry->d_lockref.count > 1 && dentry->d_inode) {
if (S_ISDIR(dentry->d_inode->i_mode) || d_mountpoint(dentry)) {
spin_unlock(&dentry->d_lock);
return -EBUSY;
@@ -606,20 +601,33 @@ EXPORT_SYMBOL(d_invalidate);
/* This must be called with d_lock held */
static inline void __dget_dlock(struct dentry *dentry)
{
- dentry->d_count++;
+ dentry->d_lockref.count++;
}
static inline void __dget(struct dentry *dentry)
{
- spin_lock(&dentry->d_lock);
- __dget_dlock(dentry);
- spin_unlock(&dentry->d_lock);
+ lockref_get(&dentry->d_lockref);
}
struct dentry *dget_parent(struct dentry *dentry)
{
+ int gotref;
struct dentry *ret;
+ /*
+ * Do optimistic parent lookup without any
+ * locking.
+ */
+ rcu_read_lock();
+ ret = ACCESS_ONCE(dentry->d_parent);
+ gotref = lockref_get_not_zero(&ret->d_lockref);
+ rcu_read_unlock();
+ if (likely(gotref)) {
+ if (likely(ret == ACCESS_ONCE(dentry->d_parent)))
+ return ret;
+ dput(ret);
+ }
+
repeat:
/*
* Don't need rcu_dereference because we re-check it was correct under
@@ -634,8 +642,8 @@ repeat:
goto repeat;
}
rcu_read_unlock();
- BUG_ON(!ret->d_count);
- ret->d_count++;
+ BUG_ON(!ret->d_lockref.count);
+ ret->d_lockref.count++;
spin_unlock(&ret->d_lock);
return ret;
}
@@ -718,7 +726,7 @@ restart:
spin_lock(&inode->i_lock);
hlist_for_each_entry(dentry, &inode->i_dentry, d_alias) {
spin_lock(&dentry->d_lock);
- if (!dentry->d_count) {
+ if (!dentry->d_lockref.count) {
__dget_dlock(dentry);
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
@@ -763,12 +771,8 @@ static void try_prune_one_dentry(struct dentry *dentry)
/* Prune ancestors. */
dentry = parent;
while (dentry) {
- spin_lock(&dentry->d_lock);
- if (dentry->d_count > 1) {
- dentry->d_count--;
- spin_unlock(&dentry->d_lock);
+ if (lockref_put_or_lock(&dentry->d_lockref))
return;
- }
dentry = dentry_kill(dentry, 1);
}
}
@@ -793,7 +797,7 @@ static void shrink_dentry_list(struct list_head *list)
* the LRU because of laziness during lookup. Do not free
* it - just keep it off the LRU list.
*/
- if (dentry->d_count) {
+ if (dentry->d_lockref.count) {
dentry_lru_del(dentry);
spin_unlock(&dentry->d_lock);
continue;
@@ -913,7 +917,7 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry)
dentry_lru_del(dentry);
__d_shrink(dentry);
- if (dentry->d_count != 0) {
+ if (dentry->d_lockref.count != 0) {
printk(KERN_ERR
"BUG: Dentry %p{i=%lx,n=%s}"
" still in use (%d)"
@@ -922,7 +926,7 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry)
dentry->d_inode ?
dentry->d_inode->i_ino : 0UL,
dentry->d_name.name,
- dentry->d_count,
+ dentry->d_lockref.count,
dentry->d_sb->s_type->name,
dentry->d_sb->s_id);
BUG();
@@ -933,7 +937,7 @@ static void shrink_dcache_for_umount_subtree(struct dentry *dentry)
list_del(&dentry->d_u.d_child);
} else {
parent = dentry->d_parent;
- parent->d_count--;
+ parent->d_lockref.count--;
list_del(&dentry->d_u.d_child);
}
@@ -981,7 +985,7 @@ void shrink_dcache_for_umount(struct super_block *sb)
dentry = sb->s_root;
sb->s_root = NULL;
- dentry->d_count--;
+ dentry->d_lockref.count--;
shrink_dcache_for_umount_subtree(dentry);
while (!hlist_bl_empty(&sb->s_anon)) {
@@ -1147,7 +1151,7 @@ resume:
* loop in shrink_dcache_parent() might not make any progress
* and loop forever.
*/
- if (dentry->d_count) {
+ if (dentry->d_lockref.count) {
dentry_lru_del(dentry);
} else if (!(dentry->d_flags & DCACHE_SHRINK_LIST)) {
dentry_lru_move_list(dentry, dispose);
@@ -1269,7 +1273,7 @@ struct dentry *__d_alloc(struct super_block *sb, const struct qstr *name)
smp_wmb();
dentry->d_name.name = dname;
- dentry->d_count = 1;
+ dentry->d_lockref.count = 1;
dentry->d_flags = 0;
spin_lock_init(&dentry->d_lock);
seqcount_init(&dentry->d_seq);
@@ -1782,7 +1786,7 @@ static noinline enum slow_d_compare slow_dentry_cmp(
* without taking d_lock and checking d_seq sequence count against @seq
* returned here.
*
- * A refcount may be taken on the found dentry with the __d_rcu_to_refcount
+ * A refcount may be taken on the found dentry with the d_rcu_to_refcount
* function.
*
* Alternatively, __d_lookup_rcu may be called again to look up the child of
@@ -1970,7 +1974,7 @@ struct dentry *__d_lookup(const struct dentry *parent, const struct qstr *name)
goto next;
}
- dentry->d_count++;
+ dentry->d_lockref.count++;
found = dentry;
spin_unlock(&dentry->d_lock);
break;
@@ -2069,7 +2073,7 @@ again:
spin_lock(&dentry->d_lock);
inode = dentry->d_inode;
isdir = S_ISDIR(inode->i_mode);
- if (dentry->d_count == 1) {
+ if (dentry->d_lockref.count == 1) {
if (!spin_trylock(&inode->i_lock)) {
spin_unlock(&dentry->d_lock);
cpu_relax();
@@ -2724,6 +2728,17 @@ char *dynamic_dname(struct dentry *dentry, char *buffer, int buflen,
return memcpy(buffer, temp, sz);
}
+char *simple_dname(struct dentry *dentry, char *buffer, int buflen)
+{
+ char *end = buffer + buflen;
+ /* these dentries are never renamed, so d_lock is not needed */
+ if (prepend(&end, &buflen, " (deleted)", 11) ||
+ prepend_name(&end, &buflen, &dentry->d_name) ||
+ prepend(&end, &buflen, "/", 1))
+ end = ERR_PTR(-ENAMETOOLONG);
+ return end;
+}
+
/*
* Write full pathname from the root of the filesystem into the buffer.
*/
@@ -2937,7 +2952,7 @@ resume:
}
if (!(dentry->d_flags & DCACHE_GENOCIDE)) {
dentry->d_flags |= DCACHE_GENOCIDE;
- dentry->d_count--;
+ dentry->d_lockref.count--;
}
spin_unlock(&dentry->d_lock);
}
@@ -2945,7 +2960,7 @@ resume:
struct dentry *child = this_parent;
if (!(this_parent->d_flags & DCACHE_GENOCIDE)) {
this_parent->d_flags |= DCACHE_GENOCIDE;
- this_parent->d_count--;
+ this_parent->d_lockref.count--;
}
this_parent = try_to_ascend(this_parent, locked, seq);
if (!this_parent)
diff --git a/fs/efs/inode.c b/fs/efs/inode.c
index f3913eb2c474..d15ccf20f1b3 100644
--- a/fs/efs/inode.c
+++ b/fs/efs/inode.c
@@ -57,7 +57,7 @@ struct inode *efs_iget(struct super_block *super, unsigned long ino)
struct inode *inode;
inode = iget_locked(super, ino);
- if (IS_ERR(inode))
+ if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 9435384562a2..544a809819c3 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1838,14 +1838,14 @@ int __init gfs2_glock_init(void)
glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM |
WQ_HIGHPRI | WQ_FREEZABLE, 0);
- if (IS_ERR(glock_workqueue))
- return PTR_ERR(glock_workqueue);
+ if (!glock_workqueue)
+ return -ENOMEM;
gfs2_delete_workqueue = alloc_workqueue("delete_workqueue",
WQ_MEM_RECLAIM | WQ_FREEZABLE,
0);
- if (IS_ERR(gfs2_delete_workqueue)) {
+ if (!gfs2_delete_workqueue) {
destroy_workqueue(glock_workqueue);
- return PTR_ERR(gfs2_delete_workqueue);
+ return -ENOMEM;
}
register_shrinker(&glock_shrinker);
diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index 5f2e5224c51c..e2e0a90396e7 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -47,7 +47,8 @@ static void gfs2_ail_error(struct gfs2_glock *gl, const struct buffer_head *bh)
* None of the buffers should be dirty, locked, or pinned.
*/
-static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
+static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync,
+ unsigned int nr_revokes)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
struct list_head *head = &gl->gl_ail_list;
@@ -57,7 +58,9 @@ static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
gfs2_log_lock(sdp);
spin_lock(&sdp->sd_ail_lock);
- list_for_each_entry_safe(bd, tmp, head, bd_ail_gl_list) {
+ list_for_each_entry_safe_reverse(bd, tmp, head, bd_ail_gl_list) {
+ if (nr_revokes == 0)
+ break;
bh = bd->bd_bh;
if (bh->b_state & b_state) {
if (fsync)
@@ -65,6 +68,7 @@ static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
gfs2_ail_error(gl, bh);
}
gfs2_trans_add_revoke(sdp, bd);
+ nr_revokes--;
}
GLOCK_BUG_ON(gl, !fsync && atomic_read(&gl->gl_ail_count));
spin_unlock(&sdp->sd_ail_lock);
@@ -91,7 +95,7 @@ static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
WARN_ON_ONCE(current->journal_info);
current->journal_info = &tr;
- __gfs2_ail_flush(gl, 0);
+ __gfs2_ail_flush(gl, 0, tr.tr_revokes);
gfs2_trans_end(sdp);
gfs2_log_flush(sdp, NULL);
@@ -101,15 +105,19 @@ void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
unsigned int revokes = atomic_read(&gl->gl_ail_count);
+ unsigned int max_revokes = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / sizeof(u64);
int ret;
if (!revokes)
return;
- ret = gfs2_trans_begin(sdp, 0, revokes);
+ while (revokes > max_revokes)
+ max_revokes += (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / sizeof(u64);
+
+ ret = gfs2_trans_begin(sdp, 0, max_revokes);
if (ret)
return;
- __gfs2_ail_flush(gl, fsync);
+ __gfs2_ail_flush(gl, fsync, max_revokes);
gfs2_trans_end(sdp);
gfs2_log_flush(sdp, NULL);
}
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index bbb2715171cd..64915eeae5a7 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -594,7 +594,7 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
}
gfs2_glock_dq_uninit(ghs);
if (IS_ERR(d))
- return PTR_RET(d);
+ return PTR_ERR(d);
return error;
} else if (error != -ENOENT) {
goto fail_gunlock;
@@ -1750,6 +1750,10 @@ static ssize_t gfs2_getxattr(struct dentry *dentry, const char *name,
struct gfs2_holder gh;
int ret;
+ /* For selinux during lookup */
+ if (gfs2_glock_is_locked_by_me(ip->i_gl))
+ return generic_getxattr(dentry, name, data, size);
+
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
ret = gfs2_glock_nq(&gh);
if (ret == 0) {
diff --git a/fs/gfs2/main.c b/fs/gfs2/main.c
index e04d0e09ee7b..7b0f5043cf24 100644
--- a/fs/gfs2/main.c
+++ b/fs/gfs2/main.c
@@ -155,7 +155,7 @@ static int __init init_gfs2_fs(void)
goto fail_wq;
gfs2_control_wq = alloc_workqueue("gfs2_control",
- WQ_NON_REENTRANT | WQ_UNBOUND | WQ_FREEZABLE, 0);
+ WQ_UNBOUND | WQ_FREEZABLE, 0);
if (!gfs2_control_wq)
goto fail_recovery;
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 34423978b170..d19b30ababf1 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -926,14 +926,8 @@ static int get_hstate_idx(int page_size_log)
return h - hstates;
}
-static char *hugetlb_dname(struct dentry *dentry, char *buffer, int buflen)
-{
- return dynamic_dname(dentry, buffer, buflen, "/%s (deleted)",
- dentry->d_name.name);
-}
-
static struct dentry_operations anon_ops = {
- .d_dname = hugetlb_dname
+ .d_dname = simple_dname
};
/*
diff --git a/fs/jfs/jfs_dtree.c b/fs/jfs/jfs_dtree.c
index 8743ba9c6742..984c2bbf4f61 100644
--- a/fs/jfs/jfs_dtree.c
+++ b/fs/jfs/jfs_dtree.c
@@ -3047,6 +3047,14 @@ int jfs_readdir(struct file *file, struct dir_context *ctx)
dir_index = (u32) ctx->pos;
+ /*
+ * NFSv4 reserves cookies 1 and 2 for . and .. so the value
+ * we return to the vfs is one greater than the one we use
+ * internally.
+ */
+ if (dir_index)
+ dir_index--;
+
if (dir_index > 1) {
struct dir_table_slot dirtab_slot;
@@ -3086,7 +3094,7 @@ int jfs_readdir(struct file *file, struct dir_context *ctx)
if (p->header.flag & BT_INTERNAL) {
jfs_err("jfs_readdir: bad index table");
DT_PUTPAGE(mp);
- ctx->pos = -1;
+ ctx->pos = DIREND;
return 0;
}
} else {
@@ -3094,14 +3102,14 @@ int jfs_readdir(struct file *file, struct dir_context *ctx)
/*
* self "."
*/
- ctx->pos = 0;
+ ctx->pos = 1;
if (!dir_emit(ctx, ".", 1, ip->i_ino, DT_DIR))
return 0;
}
/*
* parent ".."
*/
- ctx->pos = 1;
+ ctx->pos = 2;
if (!dir_emit(ctx, "..", 2, PARENT(ip), DT_DIR))
return 0;
@@ -3122,22 +3130,23 @@ int jfs_readdir(struct file *file, struct dir_context *ctx)
/*
* Legacy filesystem - OS/2 & Linux JFS < 0.3.6
*
- * pn = index = 0: First entry "."
- * pn = 0; index = 1: Second entry ".."
+ * pn = 0; index = 1: First entry "."
+ * pn = 0; index = 2: Second entry ".."
* pn > 0: Real entries, pn=1 -> leftmost page
* pn = index = -1: No more entries
*/
dtpos = ctx->pos;
- if (dtpos == 0) {
+ if (dtpos < 2) {
/* build "." entry */
+ ctx->pos = 1;
if (!dir_emit(ctx, ".", 1, ip->i_ino, DT_DIR))
return 0;
- dtoffset->index = 1;
+ dtoffset->index = 2;
ctx->pos = dtpos;
}
if (dtoffset->pn == 0) {
- if (dtoffset->index == 1) {
+ if (dtoffset->index == 2) {
/* build ".." entry */
if (!dir_emit(ctx, "..", 2, PARENT(ip), DT_DIR))
return 0;
@@ -3228,6 +3237,12 @@ int jfs_readdir(struct file *file, struct dir_context *ctx)
}
jfs_dirent->position = unique_pos++;
}
+ /*
+ * We add 1 to the index because we may
+ * use a value of 2 internally, and NFSv4
+ * doesn't like that.
+ */
+ jfs_dirent->position++;
} else {
jfs_dirent->position = dtpos;
len = min(d_namleft, DTLHDRDATALEN_LEGACY);
diff --git a/fs/namei.c b/fs/namei.c
index 89a612e392eb..2c30c84d4ea1 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -494,6 +494,50 @@ static inline void unlock_rcu_walk(void)
br_read_unlock(&vfsmount_lock);
}
+/*
+ * When we move over from the RCU domain to properly refcounted
+ * long-lived dentries, we need to check the sequence numbers
+ * we got before lookup very carefully.
+ *
+ * We cannot blindly increment a dentry refcount - even if it
+ * is not locked - if it is zero, because it may have gone
+ * through the final d_kill() logic already.
+ *
+ * So for a zero refcount, we need to get the spinlock (which is
+ * safe even for a dead dentry because the de-allocation is
+ * RCU-delayed), and check the sequence count under the lock.
+ *
+ * Once we have checked the sequence count, we know it is live,
+ * and since we hold the spinlock it cannot die from under us.
+ *
+ * In contrast, if the reference count wasn't zero, we can just
+ * increment the lockref without having to take the spinlock.
+ * Even if the sequence number ends up being stale, we haven't
+ * gone through the final dput() and killed the dentry yet.
+ */
+static inline int d_rcu_to_refcount(struct dentry *dentry, seqcount_t *validate, unsigned seq)
+{
+ int gotref;
+
+ gotref = lockref_get_or_lock(&dentry->d_lockref);
+
+ /* Does the sequence number still match? */
+ if (read_seqcount_retry(validate, seq)) {
+ if (gotref)
+ dput(dentry);
+ else
+ spin_unlock(&dentry->d_lock);
+ return -ECHILD;
+ }
+
+ /* Get the ref now, if we couldn't get it originally */
+ if (!gotref) {
+ dentry->d_lockref.count++;
+ spin_unlock(&dentry->d_lock);
+ }
+ return 0;
+}
+
/**
* unlazy_walk - try to switch to ref-walk mode.
* @nd: nameidata pathwalk data
@@ -518,29 +562,28 @@ static int unlazy_walk(struct nameidata *nd, struct dentry *dentry)
nd->root.dentry != fs->root.dentry)
goto err_root;
}
- spin_lock(&parent->d_lock);
+
+ /*
+ * For a negative lookup, the lookup sequence point is the parents
+ * sequence point, and it only needs to revalidate the parent dentry.
+ *
+ * For a positive lookup, we need to move both the parent and the
+ * dentry from the RCU domain to be properly refcounted. And the
+ * sequence number in the dentry validates *both* dentry counters,
+ * since we checked the sequence number of the parent after we got
+ * the child sequence number. So we know the parent must still
+ * be valid if the child sequence number is still valid.
+ */
if (!dentry) {
- if (!__d_rcu_to_refcount(parent, nd->seq))
- goto err_parent;
+ if (d_rcu_to_refcount(parent, &parent->d_seq, nd->seq) < 0)
+ goto err_root;
BUG_ON(nd->inode != parent->d_inode);
} else {
- if (dentry->d_parent != parent)
+ if (d_rcu_to_refcount(dentry, &dentry->d_seq, nd->seq) < 0)
+ goto err_root;
+ if (d_rcu_to_refcount(parent, &dentry->d_seq, nd->seq) < 0)
goto err_parent;
- spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
- if (!__d_rcu_to_refcount(dentry, nd->seq))
- goto err_child;
- /*
- * If the sequence check on the child dentry passed, then
- * the child has not been removed from its parent. This
- * means the parent dentry must be valid and able to take
- * a reference at this point.
- */
- BUG_ON(!IS_ROOT(dentry) && dentry->d_parent != parent);
- BUG_ON(!parent->d_count);
- parent->d_count++;
- spin_unlock(&dentry->d_lock);
}
- spin_unlock(&parent->d_lock);
if (want_root) {
path_get(&nd->root);
spin_unlock(&fs->lock);
@@ -551,10 +594,8 @@ static int unlazy_walk(struct nameidata *nd, struct dentry *dentry)
nd->flags &= ~LOOKUP_RCU;
return 0;
-err_child:
- spin_unlock(&dentry->d_lock);
err_parent:
- spin_unlock(&parent->d_lock);
+ dput(dentry);
err_root:
if (want_root)
spin_unlock(&fs->lock);
@@ -585,14 +626,11 @@ static int complete_walk(struct nameidata *nd)
nd->flags &= ~LOOKUP_RCU;
if (!(nd->flags & LOOKUP_ROOT))
nd->root.mnt = NULL;
- spin_lock(&dentry->d_lock);
- if (unlikely(!__d_rcu_to_refcount(dentry, nd->seq))) {
- spin_unlock(&dentry->d_lock);
+
+ if (d_rcu_to_refcount(dentry, &dentry->d_seq, nd->seq) < 0) {
unlock_rcu_walk();
return -ECHILD;
}
- BUG_ON(nd->inode != dentry->d_inode);
- spin_unlock(&dentry->d_lock);
mntget(nd->path.mnt);
unlock_rcu_walk();
}
@@ -3327,7 +3365,7 @@ void dentry_unhash(struct dentry *dentry)
{
shrink_dcache_parent(dentry);
spin_lock(&dentry->d_lock);
- if (dentry->d_count == 1)
+ if (dentry->d_lockref.count == 1)
__d_drop(dentry);
spin_unlock(&dentry->d_lock);
}
@@ -3671,11 +3709,15 @@ SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname,
if ((flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0)
return -EINVAL;
/*
- * Using empty names is equivalent to using AT_SYMLINK_FOLLOW
- * on /proc/self/fd/<fd>.
+ * To use null names we require CAP_DAC_READ_SEARCH
+ * This ensures that not everyone will be able to create
+ * handlink using the passed filedescriptor.
*/
- if (flags & AT_EMPTY_PATH)
+ if (flags & AT_EMPTY_PATH) {
+ if (!capable(CAP_DAC_READ_SEARCH))
+ return -ENOENT;
how = LOOKUP_EMPTY;
+ }
if (flags & AT_SYMLINK_FOLLOW)
how |= LOOKUP_FOLLOW;
diff --git a/fs/namespace.c b/fs/namespace.c
index 7b1ca9ba0b0a..a45ba4f267fe 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1429,7 +1429,7 @@ struct vfsmount *collect_mounts(struct path *path)
CL_COPY_ALL | CL_PRIVATE);
namespace_unlock();
if (IS_ERR(tree))
- return NULL;
+ return ERR_CAST(tree);
return &tree->mnt;
}
diff --git a/fs/nilfs2/segbuf.c b/fs/nilfs2/segbuf.c
index dc9a913784ab..2d8be51f90dc 100644
--- a/fs/nilfs2/segbuf.c
+++ b/fs/nilfs2/segbuf.c
@@ -345,8 +345,7 @@ static void nilfs_end_bio_write(struct bio *bio, int err)
if (err == -EOPNOTSUPP) {
set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
- bio_put(bio);
- /* to be detected by submit_seg_bio() */
+ /* to be detected by nilfs_segbuf_submit_bio() */
}
if (!uptodate)
@@ -377,12 +376,12 @@ static int nilfs_segbuf_submit_bio(struct nilfs_segment_buffer *segbuf,
bio->bi_private = segbuf;
bio_get(bio);
submit_bio(mode, bio);
+ segbuf->sb_nbio++;
if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
bio_put(bio);
err = -EOPNOTSUPP;
goto failed;
}
- segbuf->sb_nbio++;
bio_put(bio);
wi->bio = NULL;
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 854d80955bf8..121da2dc3be8 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1022,7 +1022,7 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent)
struct inode *inode = NULL;
struct ocfs2_super *osb = NULL;
struct buffer_head *bh = NULL;
- char nodestr[8];
+ char nodestr[12];
struct ocfs2_blockcheck_stats stats;
trace_ocfs2_fill_super(sb, data, silent);
diff --git a/fs/proc/fd.c b/fs/proc/fd.c
index 75f2890abbd8..0ff80f9b930f 100644
--- a/fs/proc/fd.c
+++ b/fs/proc/fd.c
@@ -230,8 +230,6 @@ static int proc_readfd_common(struct file *file, struct dir_context *ctx,
if (!dir_emit_dots(file, ctx))
goto out;
- if (!dir_emit_dots(file, ctx))
- goto out;
files = get_files_struct(p);
if (!files)
goto out;
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 94441a407337..737e15615b04 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -271,7 +271,7 @@ int proc_readdir_de(struct proc_dir_entry *de, struct file *file,
de = next;
} while (de);
spin_unlock(&proc_subdir_lock);
- return 0;
+ return 1;
}
int proc_readdir(struct file *file, struct dir_context *ctx)
diff --git a/fs/proc/root.c b/fs/proc/root.c
index 229e366598da..e0a790da726d 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -205,7 +205,9 @@ static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentr
static int proc_root_readdir(struct file *file, struct dir_context *ctx)
{
if (ctx->pos < FIRST_PROCESS_ENTRY) {
- proc_readdir(file, ctx);
+ int error = proc_readdir(file, ctx);
+ if (unlikely(error <= 0))
+ return error;
ctx->pos = FIRST_PROCESS_ENTRY;
}