summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2014-09-27 17:05:14 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-09-27 17:05:14 -0700
commit1e3827bf8aebe29af2d6e49b89d85dfae4d0154f (patch)
tree7e61ad7bcac7ef4ea9ecd46640ec3729e383c819
parent6111da3432b10b2c56a21a5d8671aee46435326d (diff)
parentd2fa4a8476b911782f7e5167db18770222ac40c3 (diff)
downloadlinux-1e3827bf8aebe29af2d6e49b89d85dfae4d0154f.tar.gz
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro: "Assorted fixes + unifying __d_move() and __d_materialise_dentry() + minimal regression fix for d_path() of victims of overwriting rename() ported on top of that" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: Don't exchange "short" filenames unconditionally. fold swapping ->d_name.hash into switch_names() fold unlocking the children into dentry_unlock_parents_for_move() kill __d_materialise_dentry() __d_materialise_dentry(): flip the order of arguments __d_move(): fold manipulations with ->d_child/->d_subdirs don't open-code d_rehash() in d_materialise_unique() pull rehashing and unlocking the target dentry into __d_materialise_dentry() ufs: deal with nfsd/iget races fuse: honour max_read and max_write in direct_io mode shmem: fix nlink for rename overwrite directory
-rw-r--r--fs/dcache.c112
-rw-r--r--fs/direct-io.c2
-rw-r--r--fs/fuse/file.c1
-rw-r--r--fs/ufs/ialloc.c6
-rw-r--r--fs/ufs/namei.c4
-rw-r--r--include/linux/uio.h2
-rw-r--r--mm/iov_iter.c14
-rw-r--r--mm/shmem.c4
8 files changed, 60 insertions, 85 deletions
diff --git a/fs/dcache.c b/fs/dcache.c
index 7a5b51440afa..cb25a1a5e307 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2372,7 +2372,8 @@ void dentry_update_name_case(struct dentry *dentry, struct qstr *name)
}
EXPORT_SYMBOL(dentry_update_name_case);
-static void switch_names(struct dentry *dentry, struct dentry *target)
+static void switch_names(struct dentry *dentry, struct dentry *target,
+ bool exchange)
{
if (dname_external(target)) {
if (dname_external(dentry)) {
@@ -2406,13 +2407,19 @@ static void switch_names(struct dentry *dentry, struct dentry *target)
*/
unsigned int i;
BUILD_BUG_ON(!IS_ALIGNED(DNAME_INLINE_LEN, sizeof(long)));
+ if (!exchange) {
+ memcpy(dentry->d_iname, target->d_name.name,
+ target->d_name.len + 1);
+ dentry->d_name.hash_len = target->d_name.hash_len;
+ return;
+ }
for (i = 0; i < DNAME_INLINE_LEN / sizeof(long); i++) {
swap(((long *) &dentry->d_iname)[i],
((long *) &target->d_iname)[i]);
}
}
}
- swap(dentry->d_name.len, target->d_name.len);
+ swap(dentry->d_name.hash_len, target->d_name.hash_len);
}
static void dentry_lock_for_move(struct dentry *dentry, struct dentry *target)
@@ -2442,25 +2449,29 @@ static void dentry_lock_for_move(struct dentry *dentry, struct dentry *target)
}
}
-static void dentry_unlock_parents_for_move(struct dentry *dentry,
- struct dentry *target)
+static void dentry_unlock_for_move(struct dentry *dentry, struct dentry *target)
{
if (target->d_parent != dentry->d_parent)
spin_unlock(&dentry->d_parent->d_lock);
if (target->d_parent != target)
spin_unlock(&target->d_parent->d_lock);
+ spin_unlock(&target->d_lock);
+ spin_unlock(&dentry->d_lock);
}
/*
* When switching names, the actual string doesn't strictly have to
* be preserved in the target - because we're dropping the target
* anyway. As such, we can just do a simple memcpy() to copy over
- * the new name before we switch.
- *
- * Note that we have to be a lot more careful about getting the hash
- * switched - we have to switch the hash value properly even if it
- * then no longer matches the actual (corrupted) string of the target.
- * The hash value has to match the hash queue that the dentry is on..
+ * the new name before we switch, unless we are going to rehash
+ * it. Note that if we *do* unhash the target, we are not allowed
+ * to rehash it without giving it a new name/hash key - whether
+ * we swap or overwrite the names here, resulting name won't match
+ * the reality in filesystem; it's only there for d_path() purposes.
+ * Note that all of this is happening under rename_lock, so the
+ * any hash lookup seeing it in the middle of manipulations will
+ * be discarded anyway. So we do not care what happens to the hash
+ * key in that case.
*/
/*
* __d_move - move a dentry
@@ -2506,36 +2517,30 @@ static void __d_move(struct dentry *dentry, struct dentry *target,
d_hash(dentry->d_parent, dentry->d_name.hash));
}
- list_del(&dentry->d_u.d_child);
- list_del(&target->d_u.d_child);
-
/* Switch the names.. */
- switch_names(dentry, target);
- swap(dentry->d_name.hash, target->d_name.hash);
+ switch_names(dentry, target, exchange);
- /* ... and switch the parents */
+ /* ... and switch them in the tree */
if (IS_ROOT(dentry)) {
+ /* splicing a tree */
dentry->d_parent = target->d_parent;
target->d_parent = target;
- INIT_LIST_HEAD(&target->d_u.d_child);
+ list_del_init(&target->d_u.d_child);
+ list_move(&dentry->d_u.d_child, &dentry->d_parent->d_subdirs);
} else {
+ /* swapping two dentries */
swap(dentry->d_parent, target->d_parent);
-
- /* And add them back to the (new) parent lists */
- list_add(&target->d_u.d_child, &target->d_parent->d_subdirs);
+ list_move(&target->d_u.d_child, &target->d_parent->d_subdirs);
+ list_move(&dentry->d_u.d_child, &dentry->d_parent->d_subdirs);
+ if (exchange)
+ fsnotify_d_move(target);
+ fsnotify_d_move(dentry);
}
- list_add(&dentry->d_u.d_child, &dentry->d_parent->d_subdirs);
-
write_seqcount_end(&target->d_seq);
write_seqcount_end(&dentry->d_seq);
- dentry_unlock_parents_for_move(dentry, target);
- if (exchange)
- fsnotify_d_move(target);
- spin_unlock(&target->d_lock);
- fsnotify_d_move(dentry);
- spin_unlock(&dentry->d_lock);
+ dentry_unlock_for_move(dentry, target);
}
/*
@@ -2633,45 +2638,6 @@ out_err:
return ret;
}
-/*
- * Prepare an anonymous dentry for life in the superblock's dentry tree as a
- * named dentry in place of the dentry to be replaced.
- * returns with anon->d_lock held!
- */
-static void __d_materialise_dentry(struct dentry *dentry, struct dentry *anon)
-{
- struct dentry *dparent;
-
- dentry_lock_for_move(anon, dentry);
-
- write_seqcount_begin(&dentry->d_seq);
- write_seqcount_begin_nested(&anon->d_seq, DENTRY_D_LOCK_NESTED);
-
- dparent = dentry->d_parent;
-
- switch_names(dentry, anon);
- swap(dentry->d_name.hash, anon->d_name.hash);
-
- dentry->d_parent = dentry;
- list_del_init(&dentry->d_u.d_child);
- anon->d_parent = dparent;
- if (likely(!d_unhashed(anon))) {
- hlist_bl_lock(&anon->d_sb->s_anon);
- __hlist_bl_del(&anon->d_hash);
- anon->d_hash.pprev = NULL;
- hlist_bl_unlock(&anon->d_sb->s_anon);
- }
- list_move(&anon->d_u.d_child, &dparent->d_subdirs);
-
- write_seqcount_end(&dentry->d_seq);
- write_seqcount_end(&anon->d_seq);
-
- dentry_unlock_parents_for_move(anon, dentry);
- spin_unlock(&dentry->d_lock);
-
- /* anon->d_lock still locked, returns locked */
-}
-
/**
* d_splice_alias - splice a disconnected dentry into the tree if one exists
* @inode: the inode which may have a disconnected dentry
@@ -2717,10 +2683,8 @@ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry)
return ERR_PTR(-EIO);
}
write_seqlock(&rename_lock);
- __d_materialise_dentry(dentry, new);
+ __d_move(new, dentry, false);
write_sequnlock(&rename_lock);
- _d_rehash(new);
- spin_unlock(&new->d_lock);
spin_unlock(&inode->i_lock);
security_d_instantiate(new, inode);
iput(inode);
@@ -2780,7 +2744,7 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode)
} else if (IS_ROOT(alias)) {
/* Is this an anonymous mountpoint that we
* could splice into our tree? */
- __d_materialise_dentry(dentry, alias);
+ __d_move(alias, dentry, false);
write_sequnlock(&rename_lock);
goto found;
} else {
@@ -2807,13 +2771,9 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode)
actual = __d_instantiate_unique(dentry, inode);
if (!actual)
actual = dentry;
- else
- BUG_ON(!d_unhashed(actual));
- spin_lock(&actual->d_lock);
+ d_rehash(actual);
found:
- _d_rehash(actual);
- spin_unlock(&actual->d_lock);
spin_unlock(&inode->i_lock);
out_nolock:
if (actual == dentry) {
diff --git a/fs/direct-io.c b/fs/direct-io.c
index c3116404ab49..e181b6b2e297 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -158,7 +158,7 @@ static inline int dio_refill_pages(struct dio *dio, struct dio_submit *sdio)
{
ssize_t ret;
- ret = iov_iter_get_pages(sdio->iter, dio->pages, DIO_PAGES,
+ ret = iov_iter_get_pages(sdio->iter, dio->pages, LONG_MAX, DIO_PAGES,
&sdio->from);
if (ret < 0 && sdio->blocks_available && (dio->rw & WRITE)) {
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 912061ac4baf..caa8d95b24e8 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1305,6 +1305,7 @@ static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
size_t start;
ssize_t ret = iov_iter_get_pages(ii,
&req->pages[req->num_pages],
+ *nbytesp - nbytes,
req->max_pages - req->num_pages,
&start);
if (ret < 0)
diff --git a/fs/ufs/ialloc.c b/fs/ufs/ialloc.c
index a9cc75ffa925..7caa01652888 100644
--- a/fs/ufs/ialloc.c
+++ b/fs/ufs/ialloc.c
@@ -298,7 +298,10 @@ cg_found:
ufsi->i_oeftflag = 0;
ufsi->i_dir_start_lookup = 0;
memset(&ufsi->i_u1, 0, sizeof(ufsi->i_u1));
- insert_inode_hash(inode);
+ if (insert_inode_locked(inode) < 0) {
+ err = -EIO;
+ goto failed;
+ }
mark_inode_dirty(inode);
if (uspi->fs_magic == UFS2_MAGIC) {
@@ -337,6 +340,7 @@ cg_found:
fail_remove_inode:
unlock_ufs(sb);
clear_nlink(inode);
+ unlock_new_inode(inode);
iput(inode);
UFSD("EXIT (FAILED): err %d\n", err);
return ERR_PTR(err);
diff --git a/fs/ufs/namei.c b/fs/ufs/namei.c
index 2df62a73f20c..fd65deb4b5f0 100644
--- a/fs/ufs/namei.c
+++ b/fs/ufs/namei.c
@@ -38,10 +38,12 @@ static inline int ufs_add_nondir(struct dentry *dentry, struct inode *inode)
{
int err = ufs_add_link(dentry, inode);
if (!err) {
+ unlock_new_inode(inode);
d_instantiate(dentry, inode);
return 0;
}
inode_dec_link_count(inode);
+ unlock_new_inode(inode);
iput(inode);
return err;
}
@@ -155,6 +157,7 @@ out_notlocked:
out_fail:
inode_dec_link_count(inode);
+ unlock_new_inode(inode);
iput(inode);
goto out;
}
@@ -210,6 +213,7 @@ out:
out_fail:
inode_dec_link_count(inode);
inode_dec_link_count(inode);
+ unlock_new_inode(inode);
iput (inode);
inode_dec_link_count(dir);
unlock_ufs(dir->i_sb);
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 48d64e6ab292..290fbf0b6b8a 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -84,7 +84,7 @@ unsigned long iov_iter_alignment(const struct iov_iter *i);
void iov_iter_init(struct iov_iter *i, int direction, const struct iovec *iov,
unsigned long nr_segs, size_t count);
ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages,
- unsigned maxpages, size_t *start);
+ size_t maxsize, unsigned maxpages, size_t *start);
ssize_t iov_iter_get_pages_alloc(struct iov_iter *i, struct page ***pages,
size_t maxsize, size_t *start);
int iov_iter_npages(const struct iov_iter *i, int maxpages);
diff --git a/mm/iov_iter.c b/mm/iov_iter.c
index ab88dc0ea1d3..9a09f2034fcc 100644
--- a/mm/iov_iter.c
+++ b/mm/iov_iter.c
@@ -310,7 +310,7 @@ void iov_iter_init(struct iov_iter *i, int direction,
EXPORT_SYMBOL(iov_iter_init);
static ssize_t get_pages_iovec(struct iov_iter *i,
- struct page **pages, unsigned maxpages,
+ struct page **pages, size_t maxsize, unsigned maxpages,
size_t *start)
{
size_t offset = i->iov_offset;
@@ -323,6 +323,8 @@ static ssize_t get_pages_iovec(struct iov_iter *i,
len = iov->iov_len - offset;
if (len > i->count)
len = i->count;
+ if (len > maxsize)
+ len = maxsize;
addr = (unsigned long)iov->iov_base + offset;
len += *start = addr & (PAGE_SIZE - 1);
if (len > maxpages * PAGE_SIZE)
@@ -588,13 +590,15 @@ static unsigned long alignment_bvec(const struct iov_iter *i)
}
static ssize_t get_pages_bvec(struct iov_iter *i,
- struct page **pages, unsigned maxpages,
+ struct page **pages, size_t maxsize, unsigned maxpages,
size_t *start)
{
const struct bio_vec *bvec = i->bvec;
size_t len = bvec->bv_len - i->iov_offset;
if (len > i->count)
len = i->count;
+ if (len > maxsize)
+ len = maxsize;
/* can't be more than PAGE_SIZE */
*start = bvec->bv_offset + i->iov_offset;
@@ -711,13 +715,13 @@ unsigned long iov_iter_alignment(const struct iov_iter *i)
EXPORT_SYMBOL(iov_iter_alignment);
ssize_t iov_iter_get_pages(struct iov_iter *i,
- struct page **pages, unsigned maxpages,
+ struct page **pages, size_t maxsize, unsigned maxpages,
size_t *start)
{
if (i->type & ITER_BVEC)
- return get_pages_bvec(i, pages, maxpages, start);
+ return get_pages_bvec(i, pages, maxsize, maxpages, start);
else
- return get_pages_iovec(i, pages, maxpages, start);
+ return get_pages_iovec(i, pages, maxsize, maxpages, start);
}
EXPORT_SYMBOL(iov_iter_get_pages);
diff --git a/mm/shmem.c b/mm/shmem.c
index 0e5fb225007c..469f90d56051 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2367,8 +2367,10 @@ static int shmem_rename2(struct inode *old_dir, struct dentry *old_dentry, struc
if (new_dentry->d_inode) {
(void) shmem_unlink(new_dir, new_dentry);
- if (they_are_dirs)
+ if (they_are_dirs) {
+ drop_nlink(new_dentry->d_inode);
drop_nlink(old_dir);
+ }
} else if (they_are_dirs) {
drop_nlink(old_dir);
inc_nlink(new_dir);