diff --git a/Documentation/filesystems/nfs/Exporting b/Documentation/filesystems/nfs/Exporting
index e543b1a619cc95b022f97d3c516687fc98f43735..c8f036a9b13fcf5d1c87761de5a97ba1248d2fee 100644
--- a/Documentation/filesystems/nfs/Exporting
+++ b/Documentation/filesystems/nfs/Exporting
@@ -66,23 +66,31 @@ b/ A per-superblock list "s_anon" of dentries which are the roots of
c/ Helper routines to allocate anonymous dentries, and to help attach
loose directory dentries at lookup time. They are:
- d_alloc_anon(inode) will return a dentry for the given inode.
+ d_obtain_alias(inode) will return a dentry for the given inode.
If the inode already has a dentry, one of those is returned.
If it doesn't, a new anonymous (IS_ROOT and
DCACHE_DISCONNECTED) dentry is allocated and attached.
In the case of a directory, care is taken that only one dentry
can ever be attached.
- d_splice_alias(inode, dentry) will make sure that there is a
- dentry with the same name and parent as the given dentry, and
- which refers to the given inode.
- If the inode is a directory and already has a dentry, then that
- dentry is d_moved over the given dentry.
- If the passed dentry gets attached, care is taken that this is
- mutually exclusive to a d_alloc_anon operation.
- If the passed dentry is used, NULL is returned, else the used
- dentry is returned. This corresponds to the calling pattern of
- ->lookup.
-
+ d_splice_alias(inode, dentry) or d_materialise_unique(dentry, inode)
+ will introduce a new dentry into the tree; either the passed-in
+ dentry or a preexisting alias for the given inode (such as an
+ anonymous one created by d_obtain_alias), if appropriate. The two
+ functions differ in their handling of directories with preexisting
+ aliases:
+ d_splice_alias will use any existing IS_ROOT dentry, but it will
+ return -EIO rather than try to move a dentry with a different
+ parent. This is appropriate for local filesystems, which
+ should never see such an alias unless the filesystem is
+ corrupted somehow (for example, if two on-disk directory
+ entries refer to the same directory.)
+ d_materialise_unique will attempt to move any dentry. This is
+ appropriate for distributed filesystems, where finding a
+ directory other than where we last cached it may be a normal
+ consequence of concurrent operations on other hosts.
+ Both functions return NULL when the passed-in dentry is used,
+ following the calling convention of ->lookup.
+
Filesystem Issues
-----------------
@@ -120,12 +128,12 @@ struct which has the following members:
fh_to_dentry (mandatory)
Given a filehandle fragment, this should find the implied object and
- create a dentry for it (possibly with d_alloc_anon).
+ create a dentry for it (possibly with d_obtain_alias).
fh_to_parent (optional but strongly recommended)
Given a filehandle fragment, this should find the parent of the
- implied object and create a dentry for it (possibly with d_alloc_anon).
- May fail if the filehandle fragment is too small.
+ implied object and create a dentry for it (possibly with
+ d_obtain_alias). May fail if the filehandle fragment is too small.
get_parent (optional but strongly recommended)
When given a dentry for a directory, this should return a dentry for
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index a1d0d7a301657d674c653648534ee5be527919b9..61d65cc65c54a333bef994fc49f881ece37032c5 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -1053,7 +1053,8 @@ struct dentry_operations {
If the 'rcu_walk' parameter is true, then the caller is doing a
pathwalk in RCU-walk mode. Sleeping is not permitted in this mode,
and the caller can be asked to leave it and call again by returning
- -ECHILD.
+ -ECHILD. -EISDIR may also be returned to tell pathwalk to
+ ignore d_automount or any mounts.
This function is only used if DCACHE_MANAGE_TRANSIT is set on the
dentry being transited from.
diff --git a/fs/Makefile b/fs/Makefile
index 4030cbfbc9af8572673eb06c997603ee529443e4..90c88529892bfc9723a9aec9ed6540daeb372f76 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -11,7 +11,7 @@ obj-y := open.o read_write.o file_table.o super.o \
attr.o bad_inode.o file.o filesystems.o namespace.o \
seq_file.o xattr.o libfs.o fs-writeback.o \
pnode.o splice.o sync.o utimes.o \
- stack.o fs_struct.o statfs.o
+ stack.o fs_struct.o statfs.o fs_pin.o
ifeq ($(CONFIG_BLOCK),y)
obj-y += buffer.o block_dev.o direct-io.o mpage.o
diff --git a/fs/bad_inode.c b/fs/bad_inode.c
index 7c93953030fbe5eda13d76b6a8c53d6f2a31902d..afd2b4408adf53d78c716043c847ba48cf5c3bef 100644
--- a/fs/bad_inode.c
+++ b/fs/bad_inode.c
@@ -218,8 +218,9 @@ static int bad_inode_mknod (struct inode *dir, struct dentry *dentry,
return -EIO;
}
-static int bad_inode_rename (struct inode *old_dir, struct dentry *old_dentry,
- struct inode *new_dir, struct dentry *new_dentry)
+static int bad_inode_rename2(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
{
return -EIO;
}
@@ -279,7 +280,7 @@ static const struct inode_operations bad_inode_ops =
.mkdir = bad_inode_mkdir,
.rmdir = bad_inode_rmdir,
.mknod = bad_inode_mknod,
- .rename = bad_inode_rename,
+ .rename2 = bad_inode_rename2,
.readlink = bad_inode_readlink,
/* follow_link must be no-op, otherwise unmounting this inode
won't work */
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 3668048e16f8fa835c3ffff9ed85998ee201ec58..3183742d6f0d74d131c16e29dde59205f3e7f8a4 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8476,6 +8476,16 @@ static int btrfs_rename(struct inode *old_dir, struct dentry *old_dentry,
return ret;
}
+static int btrfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
+{
+ if (flags & ~RENAME_NOREPLACE)
+ return -EINVAL;
+
+ return btrfs_rename(old_dir, old_dentry, new_dir, new_dentry);
+}
+
static void btrfs_run_delalloc_work(struct btrfs_work *work)
{
struct btrfs_delalloc_work *delalloc_work;
@@ -9019,7 +9029,7 @@ static const struct inode_operations btrfs_dir_inode_operations = {
.link = btrfs_link,
.mkdir = btrfs_mkdir,
.rmdir = btrfs_rmdir,
- .rename = btrfs_rename,
+ .rename2 = btrfs_rename2,
.symlink = btrfs_symlink,
.setattr = btrfs_setattr,
.mknod = btrfs_mknod,
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 8e16bca69c56de7fa54c1680698b60d7319a03a9..67b48b9a03e044eb2d83ab28447c8ead9db5192b 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -851,7 +851,6 @@ static struct dentry *get_default_root(struct super_block *sb,
struct btrfs_path *path;
struct btrfs_key location;
struct inode *inode;
- struct dentry *dentry;
u64 dir_id;
int new = 0;
@@ -922,13 +921,7 @@ static struct dentry *get_default_root(struct super_block *sb,
return dget(sb->s_root);
}
- dentry = d_obtain_alias(inode);
- if (!IS_ERR(dentry)) {
- spin_lock(&dentry->d_lock);
- dentry->d_flags &= ~DCACHE_DISCONNECTED;
- spin_unlock(&dentry->d_lock);
- }
- return dentry;
+ return d_obtain_root(inode);
}
static int btrfs_fill_super(struct super_block *sb,
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index 06150fd745ac65d72c456b1fe57f537336f1064a..f6e12377335c1a2aa030e86f1d903daa365792b1 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -755,7 +755,7 @@ static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
goto out;
}
} else {
- root = d_obtain_alias(inode);
+ root = d_obtain_root(inode);
}
ceph_init_dentry(root);
dout("open_root_inode success, root dentry is %p\n", root);
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 88839806742007ca8dfaf8d77754695d4924fef9..ac4f260155c875b80d9d6611af1139438e62fc91 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -848,7 +848,7 @@ const struct inode_operations cifs_dir_inode_ops = {
.link = cifs_hardlink,
.mkdir = cifs_mkdir,
.rmdir = cifs_rmdir,
- .rename = cifs_rename,
+ .rename2 = cifs_rename2,
.permission = cifs_permission,
/* revalidate:cifs_revalidate, */
.setattr = cifs_setattr,
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 560480263336ce23a4ffa456b76e02f59f71c0fd..b0fafa499505218fb0cecac43cfb9db4e9a77f26 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -68,8 +68,8 @@ extern int cifs_hardlink(struct dentry *, struct inode *, struct dentry *);
extern int cifs_mknod(struct inode *, struct dentry *, umode_t, dev_t);
extern int cifs_mkdir(struct inode *, struct dentry *, umode_t);
extern int cifs_rmdir(struct inode *, struct dentry *);
-extern int cifs_rename(struct inode *, struct dentry *, struct inode *,
- struct dentry *);
+extern int cifs_rename2(struct inode *, struct dentry *, struct inode *,
+ struct dentry *, unsigned int);
extern int cifs_revalidate_file_attr(struct file *filp);
extern int cifs_revalidate_dentry_attr(struct dentry *);
extern int cifs_revalidate_file(struct file *filp);
diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 41de3935caa0cff86e58e8c4a0db829e4ca88a7e..426d6c6ad8bfacfa188f2eb2dfb5385620559f44 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -1627,8 +1627,9 @@ cifs_do_rename(const unsigned int xid, struct dentry *from_dentry,
}
int
-cifs_rename(struct inode *source_dir, struct dentry *source_dentry,
- struct inode *target_dir, struct dentry *target_dentry)
+cifs_rename2(struct inode *source_dir, struct dentry *source_dentry,
+ struct inode *target_dir, struct dentry *target_dentry,
+ unsigned int flags)
{
char *from_name = NULL;
char *to_name = NULL;
@@ -1640,6 +1641,9 @@ cifs_rename(struct inode *source_dir, struct dentry *source_dentry,
unsigned int xid;
int rc, tmprc;
+ if (flags & ~RENAME_NOREPLACE)
+ return -EINVAL;
+
cifs_sb = CIFS_SB(source_dir->i_sb);
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink))
@@ -1667,6 +1671,12 @@ cifs_rename(struct inode *source_dir, struct dentry *source_dentry,
rc = cifs_do_rename(xid, source_dentry, from_name, target_dentry,
to_name);
+ /*
+ * No-replace is the natural behavior for CIFS, so skip unlink hacks.
+ */
+ if (flags & RENAME_NOREPLACE)
+ goto cifs_rename_exit;
+
if (rc == -EEXIST && tcon->unix_ext) {
/*
* Are src and dst hardlinks of same inode? We can only tell
diff --git a/fs/dcache.c b/fs/dcache.c
index 06f65857a855725247c1190d243c0e19cccd8570..d30ce699ae4b6ea4ac3ad1b8ec955fa271bdcb16 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -731,8 +731,6 @@ EXPORT_SYMBOL(dget_parent);
/**
* d_find_alias - grab a hashed alias of inode
* @inode: inode in question
- * @want_discon: flag, used by d_splice_alias, to request
- * that only a DISCONNECTED alias be returned.
*
* If inode has a hashed alias, or is a directory and has any alias,
* acquire the reference to alias and return it. Otherwise return NULL.
@@ -741,10 +739,9 @@ EXPORT_SYMBOL(dget_parent);
* of a filesystem.
*
* If the inode has an IS_ROOT, DCACHE_DISCONNECTED alias, then prefer
- * any other hashed alias over that one unless @want_discon is set,
- * in which case only return an IS_ROOT, DCACHE_DISCONNECTED alias.
+ * any other hashed alias over that one.
*/
-static struct dentry *__d_find_alias(struct inode *inode, int want_discon)
+static struct dentry *__d_find_alias(struct inode *inode)
{
struct dentry *alias, *discon_alias;
@@ -756,7 +753,7 @@ static struct dentry *__d_find_alias(struct inode *inode, int want_discon)
if (IS_ROOT(alias) &&
(alias->d_flags & DCACHE_DISCONNECTED)) {
discon_alias = alias;
- } else if (!want_discon) {
+ } else {
__dget_dlock(alias);
spin_unlock(&alias->d_lock);
return alias;
@@ -768,12 +765,9 @@ static struct dentry *__d_find_alias(struct inode *inode, int want_discon)
alias = discon_alias;
spin_lock(&alias->d_lock);
if (S_ISDIR(inode->i_mode) || !d_unhashed(alias)) {
- if (IS_ROOT(alias) &&
- (alias->d_flags & DCACHE_DISCONNECTED)) {
- __dget_dlock(alias);
- spin_unlock(&alias->d_lock);
- return alias;
- }
+ __dget_dlock(alias);
+ spin_unlock(&alias->d_lock);
+ return alias;
}
spin_unlock(&alias->d_lock);
goto again;
@@ -787,7 +781,7 @@ struct dentry *d_find_alias(struct inode *inode)
if (!hlist_empty(&inode->i_dentry)) {
spin_lock(&inode->i_lock);
- de = __d_find_alias(inode, 0);
+ de = __d_find_alias(inode);
spin_unlock(&inode->i_lock);
}
return de;
@@ -1781,25 +1775,7 @@ struct dentry *d_find_any_alias(struct inode *inode)
}
EXPORT_SYMBOL(d_find_any_alias);
-/**
- * d_obtain_alias - find or allocate a dentry for a given inode
- * @inode: inode to allocate the dentry for
- *
- * Obtain a dentry for an inode resulting from NFS filehandle conversion or
- * similar open by handle operations. The returned dentry may be anonymous,
- * or may have a full name (if the inode was already in the cache).
- *
- * When called on a directory inode, we must ensure that the inode only ever
- * has one dentry. If a dentry is found, that is returned instead of
- * allocating a new one.
- *
- * On successful return, the reference to the inode has been transferred
- * to the dentry. In case of an error the reference on the inode is released.
- * To make it easier to use in export operations a %NULL or IS_ERR inode may
- * be passed in and will be the error will be propagate to the return value,
- * with a %NULL @inode replaced by ERR_PTR(-ESTALE).
- */
-struct dentry *d_obtain_alias(struct inode *inode)
+static struct dentry *__d_obtain_alias(struct inode *inode, int disconnected)
{
static const struct qstr anonstring = QSTR_INIT("/", 1);
struct dentry *tmp;
@@ -1830,7 +1806,10 @@ struct dentry *d_obtain_alias(struct inode *inode)
}
/* attach a disconnected dentry */
- add_flags = d_flags_for_inode(inode) | DCACHE_DISCONNECTED;
+ add_flags = d_flags_for_inode(inode);
+
+ if (disconnected)
+ add_flags |= DCACHE_DISCONNECTED;
spin_lock(&tmp->d_lock);
tmp->d_inode = inode;
@@ -1851,59 +1830,51 @@ struct dentry *d_obtain_alias(struct inode *inode)
iput(inode);
return res;
}
-EXPORT_SYMBOL(d_obtain_alias);
/**
- * d_splice_alias - splice a disconnected dentry into the tree if one exists
- * @inode: the inode which may have a disconnected dentry
- * @dentry: a negative dentry which we want to point to the inode.
- *
- * If inode is a directory and has a 'disconnected' dentry (i.e. IS_ROOT and
- * DCACHE_DISCONNECTED), then d_move that in place of the given dentry
- * and return it, else simply d_add the inode to the dentry and return NULL.
+ * d_obtain_alias - find or allocate a DISCONNECTED dentry for a given inode
+ * @inode: inode to allocate the dentry for
*
- * This is needed in the lookup routine of any filesystem that is exportable
- * (via knfsd) so that we can build dcache paths to directories effectively.
+ * Obtain a dentry for an inode resulting from NFS filehandle conversion or
+ * similar open by handle operations. The returned dentry may be anonymous,
+ * or may have a full name (if the inode was already in the cache).
*
- * If a dentry was found and moved, then it is returned. Otherwise NULL
- * is returned. This matches the expected return value of ->lookup.
+ * When called on a directory inode, we must ensure that the inode only ever
+ * has one dentry. If a dentry is found, that is returned instead of
+ * allocating a new one.
*
- * Cluster filesystems may call this function with a negative, hashed dentry.
- * In that case, we know that the inode will be a regular file, and also this
- * will only occur during atomic_open. So we need to check for the dentry
- * being already hashed only in the final case.
+ * On successful return, the reference to the inode has been transferred
+ * to the dentry. In case of an error the reference on the inode is released.
+ * To make it easier to use in export operations a %NULL or IS_ERR inode may
+ * be passed in and the error will be propagated to the return value,
+ * with a %NULL @inode replaced by ERR_PTR(-ESTALE).
*/
-struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry)
+struct dentry *d_obtain_alias(struct inode *inode)
{
- struct dentry *new = NULL;
-
- if (IS_ERR(inode))
- return ERR_CAST(inode);
+ return __d_obtain_alias(inode, 1);
+}
+EXPORT_SYMBOL(d_obtain_alias);
- if (inode && S_ISDIR(inode->i_mode)) {
- spin_lock(&inode->i_lock);
- new = __d_find_alias(inode, 1);
- if (new) {
- BUG_ON(!(new->d_flags & DCACHE_DISCONNECTED));
- spin_unlock(&inode->i_lock);
- security_d_instantiate(new, inode);
- d_move(new, dentry);
- iput(inode);
- } else {
- /* already taking inode->i_lock, so d_add() by hand */
- __d_instantiate(dentry, inode);
- spin_unlock(&inode->i_lock);
- security_d_instantiate(dentry, inode);
- d_rehash(dentry);
- }
- } else {
- d_instantiate(dentry, inode);
- if (d_unhashed(dentry))
- d_rehash(dentry);
- }
- return new;
+/**
+ * d_obtain_root - find or allocate a dentry for a given inode
+ * @inode: inode to allocate the dentry for
+ *
+ * Obtain an IS_ROOT dentry for the root of a filesystem.
+ *
+ * We must ensure that directory inodes only ever have one dentry. If a
+ * dentry is found, that is returned instead of allocating a new one.
+ *
+ * On successful return, the reference to the inode has been transferred
+ * to the dentry. In case of an error the reference on the inode is
+ * released. A %NULL or IS_ERR inode may be passed in and will be the
+ * error will be propagate to the return value, with a %NULL @inode
+ * replaced by ERR_PTR(-ESTALE).
+ */
+struct dentry *d_obtain_root(struct inode *inode)
+{
+ return __d_obtain_alias(inode, 0);
}
-EXPORT_SYMBOL(d_splice_alias);
+EXPORT_SYMBOL(d_obtain_root);
/**
* d_add_ci - lookup or allocate new dentry with case-exact name
@@ -2696,6 +2667,75 @@ static void __d_materialise_dentry(struct dentry *dentry, struct dentry *anon)
/* 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
+ * @dentry: a negative dentry which we want to point to the inode.
+ *
+ * If inode is a directory and has an IS_ROOT alias, then d_move that in
+ * place of the given dentry and return it, else simply d_add the inode
+ * to the dentry and return NULL.
+ *
+ * If a non-IS_ROOT directory is found, the filesystem is corrupt, and
+ * we should error out: directories can't have multiple aliases.
+ *
+ * This is needed in the lookup routine of any filesystem that is exportable
+ * (via knfsd) so that we can build dcache paths to directories effectively.
+ *
+ * If a dentry was found and moved, then it is returned. Otherwise NULL
+ * is returned. This matches the expected return value of ->lookup.
+ *
+ * Cluster filesystems may call this function with a negative, hashed dentry.
+ * In that case, we know that the inode will be a regular file, and also this
+ * will only occur during atomic_open. So we need to check for the dentry
+ * being already hashed only in the final case.
+ */
+struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry)
+{
+ struct dentry *new = NULL;
+
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+
+ if (inode && S_ISDIR(inode->i_mode)) {
+ spin_lock(&inode->i_lock);
+ new = __d_find_any_alias(inode);
+ if (new) {
+ if (!IS_ROOT(new)) {
+ spin_unlock(&inode->i_lock);
+ dput(new);
+ return ERR_PTR(-EIO);
+ }
+ if (d_ancestor(new, dentry)) {
+ spin_unlock(&inode->i_lock);
+ dput(new);
+ return ERR_PTR(-EIO);
+ }
+ write_seqlock(&rename_lock);
+ __d_materialise_dentry(dentry, new);
+ write_sequnlock(&rename_lock);
+ __d_drop(new);
+ _d_rehash(new);
+ spin_unlock(&new->d_lock);
+ spin_unlock(&inode->i_lock);
+ security_d_instantiate(new, inode);
+ iput(inode);
+ } else {
+ /* already taking inode->i_lock, so d_add() by hand */
+ __d_instantiate(dentry, inode);
+ spin_unlock(&inode->i_lock);
+ security_d_instantiate(dentry, inode);
+ d_rehash(dentry);
+ }
+ } else {
+ d_instantiate(dentry, inode);
+ if (d_unhashed(dentry))
+ d_rehash(dentry);
+ }
+ return new;
+}
+EXPORT_SYMBOL(d_splice_alias);
+
/**
* d_materialise_unique - introduce an inode into the tree
* @dentry: candidate dentry
@@ -2724,7 +2764,7 @@ struct dentry *d_materialise_unique(struct dentry *dentry, struct inode *inode)
struct dentry *alias;
/* Does an aliased dentry already exist? */
- alias = __d_find_alias(inode, 0);
+ alias = __d_find_alias(inode);
if (alias) {
actual = alias;
write_seqlock(&rename_lock);
diff --git a/fs/direct-io.c b/fs/direct-io.c
index 17e39b047de5b8a64349c86a5f9432efcb19f2e5..c3116404ab49a29c3b11fb53c175132f715750a5 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 * PAGE_SIZE,
+ ret = iov_iter_get_pages(sdio->iter, dio->pages, DIO_PAGES,
&sdio->from);
if (ret < 0 && sdio->blocks_available && (dio->rw & WRITE)) {
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 3520ab8a66390c03d0fd95adccb6d7c8d74bb0c7..b147a67baa0d976d026857308350d85b8de72e01 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -3455,7 +3455,6 @@ const struct inode_operations ext4_dir_inode_operations = {
.rmdir = ext4_rmdir,
.mknod = ext4_mknod,
.tmpfile = ext4_tmpfile,
- .rename = ext4_rename,
.rename2 = ext4_rename2,
.setattr = ext4_setattr,
.setxattr = generic_setxattr,
diff --git a/fs/fs_pin.c b/fs/fs_pin.c
new file mode 100644
index 0000000000000000000000000000000000000000..9368236ca100bc311fe721c15eca9e3bfdcb2f0f
--- /dev/null
+++ b/fs/fs_pin.c
@@ -0,0 +1,78 @@
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/fs_pin.h>
+#include "internal.h"
+#include "mount.h"
+
+static void pin_free_rcu(struct rcu_head *head)
+{
+ kfree(container_of(head, struct fs_pin, rcu));
+}
+
+static DEFINE_SPINLOCK(pin_lock);
+
+void pin_put(struct fs_pin *p)
+{
+ if (atomic_long_dec_and_test(&p->count))
+ call_rcu(&p->rcu, pin_free_rcu);
+}
+
+void pin_remove(struct fs_pin *pin)
+{
+ spin_lock(&pin_lock);
+ hlist_del(&pin->m_list);
+ hlist_del(&pin->s_list);
+ spin_unlock(&pin_lock);
+}
+
+void pin_insert(struct fs_pin *pin, struct vfsmount *m)
+{
+ spin_lock(&pin_lock);
+ hlist_add_head(&pin->s_list, &m->mnt_sb->s_pins);
+ hlist_add_head(&pin->m_list, &real_mount(m)->mnt_pins);
+ spin_unlock(&pin_lock);
+}
+
+void mnt_pin_kill(struct mount *m)
+{
+ while (1) {
+ struct hlist_node *p;
+ struct fs_pin *pin;
+ rcu_read_lock();
+ p = ACCESS_ONCE(m->mnt_pins.first);
+ if (!p) {
+ rcu_read_unlock();
+ break;
+ }
+ pin = hlist_entry(p, struct fs_pin, m_list);
+ if (!atomic_long_inc_not_zero(&pin->count)) {
+ rcu_read_unlock();
+ cpu_relax();
+ continue;
+ }
+ rcu_read_unlock();
+ pin->kill(pin);
+ }
+}
+
+void sb_pin_kill(struct super_block *sb)
+{
+ while (1) {
+ struct hlist_node *p;
+ struct fs_pin *pin;
+ rcu_read_lock();
+ p = ACCESS_ONCE(sb->s_pins.first);
+ if (!p) {
+ rcu_read_unlock();
+ break;
+ }
+ pin = hlist_entry(p, struct fs_pin, s_list);
+ if (!atomic_long_inc_not_zero(&pin->count)) {
+ rcu_read_unlock();
+ cpu_relax();
+ continue;
+ }
+ rcu_read_unlock();
+ pin->kill(pin);
+ }
+}
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 0c6048247a34eb16a5146f7ea67479a21fec6173..de1d84af9f7c6baf27b64218fbff43604ab47c04 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -845,12 +845,6 @@ static int fuse_rename2(struct inode *olddir, struct dentry *oldent,
return err;
}
-static int fuse_rename(struct inode *olddir, struct dentry *oldent,
- struct inode *newdir, struct dentry *newent)
-{
- return fuse_rename2(olddir, oldent, newdir, newent, 0);
-}
-
static int fuse_link(struct dentry *entry, struct inode *newdir,
struct dentry *newent)
{
@@ -2024,7 +2018,6 @@ static const struct inode_operations fuse_dir_inode_operations = {
.symlink = fuse_symlink,
.unlink = fuse_unlink,
.rmdir = fuse_rmdir,
- .rename = fuse_rename,
.rename2 = fuse_rename2,
.link = fuse_link,
.setattr = fuse_setattr,
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 40ac2628ddcf46f3be8fe96ed46bb37ee6ef1c62..912061ac4baf9e6eeca15ea82394052e2583a809 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1303,10 +1303,10 @@ static int fuse_get_user_pages(struct fuse_req *req, struct iov_iter *ii,
while (nbytes < *nbytesp && req->num_pages < req->max_pages) {
unsigned npages;
size_t start;
- unsigned n = req->max_pages - req->num_pages;
ssize_t ret = iov_iter_get_pages(ii,
&req->pages[req->num_pages],
- n * PAGE_SIZE, &start);
+ req->max_pages - req->num_pages,
+ &start);
if (ret < 0)
return ret;
diff --git a/fs/hostfs/hostfs.h b/fs/hostfs/hostfs.h
index 9c88da0e855a1001fd50e9979c3cc487d7bc80dc..4fcd40d6f30820817892e4908477aefc06073e85 100644
--- a/fs/hostfs/hostfs.h
+++ b/fs/hostfs/hostfs.h
@@ -89,6 +89,7 @@ extern int do_mknod(const char *file, int mode, unsigned int major,
extern int link_file(const char *from, const char *to);
extern int hostfs_do_readlink(char *file, char *buf, int size);
extern int rename_file(char *from, char *to);
+extern int rename2_file(char *from, char *to, unsigned int flags);
extern int do_statfs(char *root, long *bsize_out, long long *blocks_out,
long long *bfree_out, long long *bavail_out,
long long *files_out, long long *ffree_out,
diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index bb529f3b7f2bf8a119ec5f2eba3c260e09c361c7..fd62cae0fdcb66db03712d419c25014312112546 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -741,21 +741,31 @@ static int hostfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
return err;
}
-static int hostfs_rename(struct inode *from_ino, struct dentry *from,
- struct inode *to_ino, struct dentry *to)
+static int hostfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
{
- char *from_name, *to_name;
+ char *old_name, *new_name;
int err;
- if ((from_name = dentry_name(from)) == NULL)
+ if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
+ return -EINVAL;
+
+ old_name = dentry_name(old_dentry);
+ if (old_name == NULL)
return -ENOMEM;
- if ((to_name = dentry_name(to)) == NULL) {
- __putname(from_name);
+ new_name = dentry_name(new_dentry);
+ if (new_name == NULL) {
+ __putname(old_name);
return -ENOMEM;
}
- err = rename_file(from_name, to_name);
- __putname(from_name);
- __putname(to_name);
+ if (!flags)
+ err = rename_file(old_name, new_name);
+ else
+ err = rename2_file(old_name, new_name, flags);
+
+ __putname(old_name);
+ __putname(new_name);
return err;
}
@@ -867,7 +877,7 @@ static const struct inode_operations hostfs_dir_iops = {
.mkdir = hostfs_mkdir,
.rmdir = hostfs_rmdir,
.mknod = hostfs_mknod,
- .rename = hostfs_rename,
+ .rename2 = hostfs_rename2,
.permission = hostfs_permission,
.setattr = hostfs_setattr,
};
diff --git a/fs/hostfs/hostfs_user.c b/fs/hostfs/hostfs_user.c
index 67838f3aa20a8fa6937eb6e48b39a9bef15d51aa..9765dab95cbdaefa4e53d8fdd51a72ffca4e6061 100644
--- a/fs/hostfs/hostfs_user.c
+++ b/fs/hostfs/hostfs_user.c
@@ -14,6 +14,7 @@
#include <sys/time.h>
#include <sys/types.h>
#include <sys/vfs.h>
+#include <sys/syscall.h>
#include "hostfs.h"
#include <utime.h>
@@ -360,6 +361,33 @@ int rename_file(char *from, char *to)
return 0;
}
+int rename2_file(char *from, char *to, unsigned int flags)
+{
+ int err;
+
+#ifndef SYS_renameat2
+# ifdef __x86_64__
+# define SYS_renameat2 316
+# endif
+# ifdef __i386__
+# define SYS_renameat2 353
+# endif
+#endif
+
+#ifdef SYS_renameat2
+ err = syscall(SYS_renameat2, AT_FDCWD, from, AT_FDCWD, to, flags);
+ if (err < 0) {
+ if (errno != ENOSYS)
+ return -errno;
+ else
+ return -EINVAL;
+ }
+ return 0;
+#else
+ return -EINVAL;
+#endif
+}
+
int do_statfs(char *root, long *bsize_out, long long *blocks_out,
long long *bfree_out, long long *bavail_out,
long long *files_out, long long *ffree_out,
diff --git a/fs/internal.h b/fs/internal.h
index 4657424074668dcb933c8d375244b1d3b9d72561..e325b4f9c799669ebfa02e0ee143231e98510ba6 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -131,7 +131,6 @@ extern long prune_dcache_sb(struct super_block *sb, unsigned long nr_to_scan,
/*
* read_write.c
*/
-extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *);
extern int rw_verify_area(int, struct file *, const loff_t *, size_t);
/*
@@ -144,3 +143,9 @@ extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
* pipe.c
*/
extern const struct file_operations pipefifo_fops;
+
+/*
+ * fs_pin.c
+ */
+extern void sb_pin_kill(struct super_block *sb);
+extern void mnt_pin_kill(struct mount *m);
diff --git a/fs/mount.h b/fs/mount.h
index d55297f2fa058c18512d0136b8a5437b29bc481c..6740a621552950e7a795b249f635b5eeea7065d1 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -55,7 +55,7 @@ struct mount {
int mnt_id; /* mount identifier */
int mnt_group_id; /* peer group identifier */
int mnt_expiry_mark; /* true if marked for expiry */
- int mnt_pinned;
+ struct hlist_head mnt_pins;
struct path mnt_ex_mountpoint;
};
diff --git a/fs/namei.c b/fs/namei.c
index 9eb787e5c167fb601845590f0181d249bf515fb0..a996bb48dfabf4f645dced56f527ed3d5568bb2c 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1091,10 +1091,10 @@ int follow_down_one(struct path *path)
}
EXPORT_SYMBOL(follow_down_one);
-static inline bool managed_dentry_might_block(struct dentry *dentry)
+static inline int managed_dentry_rcu(struct dentry *dentry)
{
- return (dentry->d_flags & DCACHE_MANAGE_TRANSIT &&
- dentry->d_op->d_manage(dentry, true) < 0);
+ return (dentry->d_flags & DCACHE_MANAGE_TRANSIT) ?
+ dentry->d_op->d_manage(dentry, true) : 0;
}
/*
@@ -1110,11 +1110,18 @@ static bool __follow_mount_rcu(struct nameidata *nd, struct path *path,
* Don't forget we might have a non-mountpoint managed dentry
* that wants to block transit.
*/
- if (unlikely(managed_dentry_might_block(path->dentry)))
+ switch (managed_dentry_rcu(path->dentry)) {
+ case -ECHILD:
+ default:
return false;
+ case -EISDIR:
+ return true;
+ case 0:
+ break;
+ }
if (!d_mountpoint(path->dentry))
- return true;
+ return !(path->dentry->d_flags & DCACHE_NEED_AUTOMOUNT);
mounted = __lookup_mnt(path->mnt, path->dentry);
if (!mounted)
@@ -1130,7 +1137,8 @@ static bool __follow_mount_rcu(struct nameidata *nd, struct path *path,
*/
*inode = path->dentry->d_inode;
}
- return read_seqretry(&mount_lock, nd->m_seq);
+ return read_seqretry(&mount_lock, nd->m_seq) &&
+ !(path->dentry->d_flags & DCACHE_NEED_AUTOMOUNT);
}
static int follow_dotdot_rcu(struct nameidata *nd)
@@ -1402,11 +1410,8 @@ static int lookup_fast(struct nameidata *nd,
}
path->mnt = mnt;
path->dentry = dentry;
- if (unlikely(!__follow_mount_rcu(nd, path, inode)))
- goto unlazy;
- if (unlikely(path->dentry->d_flags & DCACHE_NEED_AUTOMOUNT))
- goto unlazy;
- return 0;
+ if (likely(__follow_mount_rcu(nd, path, inode)))
+ return 0;
unlazy:
if (unlazy_walk(nd, dentry))
return -ECHILD;
@@ -4019,7 +4024,7 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname
* The worst of all namespace operations - renaming directory. "Perverted"
* doesn't even start to describe it. Somebody in UCB had a heck of a trip...
* Problems:
- * a) we can get into loop creation. Check is done in is_subdir().
+ * a) we can get into loop creation.
* b) race potential - two innocent renames can create a loop together.
* That's where 4.4 screws up. Current fix: serialization on
* sb->s_vfs_rename_mutex. We might be more accurate, but that's another
@@ -4075,7 +4080,7 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
if (error)
return error;
- if (!old_dir->i_op->rename)
+ if (!old_dir->i_op->rename && !old_dir->i_op->rename2)
return -EPERM;
if (flags && !old_dir->i_op->rename2)
@@ -4134,10 +4139,11 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry,
if (error)
goto out;
}
- if (!flags) {
+ if (!old_dir->i_op->rename2) {
error = old_dir->i_op->rename(old_dir, old_dentry,
new_dir, new_dentry);
} else {
+ WARN_ON(old_dir->i_op->rename != NULL);
error = old_dir->i_op->rename2(old_dir, old_dentry,
new_dir, new_dentry, flags);
}
diff --git a/fs/namespace.c b/fs/namespace.c
index 0acabea583191aaa427fab317429210756e1a643..a01c7730e9af3ad07f3e993d2f7f27f04f615604 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -16,7 +16,6 @@
#include <linux/namei.h>
#include <linux/security.h>
#include <linux/idr.h>
-#include <linux/acct.h> /* acct_auto_close_mnt */
#include <linux/init.h> /* init_rootfs */
#include <linux/fs_struct.h> /* get_fs_root et.al. */
#include <linux/fsnotify.h> /* fsnotify_vfsmount_delete */
@@ -779,6 +778,20 @@ static void attach_mnt(struct mount *mnt,
list_add_tail(&mnt->mnt_child, &parent->mnt_mounts);
}
+static void attach_shadowed(struct mount *mnt,
+ struct mount *parent,
+ struct mount *shadows)
+{
+ if (shadows) {
+ hlist_add_behind_rcu(&mnt->mnt_hash, &shadows->mnt_hash);
+ list_add(&mnt->mnt_child, &shadows->mnt_child);
+ } else {
+ hlist_add_head_rcu(&mnt->mnt_hash,
+ m_hash(&parent->mnt, mnt->mnt_mountpoint));
+ list_add_tail(&mnt->mnt_child, &parent->mnt_mounts);
+ }
+}
+
/*
* vfsmount lock must be held for write
*/
@@ -797,12 +810,7 @@ static void commit_tree(struct mount *mnt, struct mount *shadows)
list_splice(&head, n->list.prev);
- if (shadows)
- hlist_add_behind_rcu(&mnt->mnt_hash, &shadows->mnt_hash);
- else
- hlist_add_head_rcu(&mnt->mnt_hash,
- m_hash(&parent->mnt, mnt->mnt_mountpoint));
- list_add_tail(&mnt->mnt_child, &parent->mnt_mounts);
+ attach_shadowed(mnt, parent, shadows);
touch_mnt_namespace(n);
}
@@ -951,7 +959,6 @@ static struct mount *clone_mnt(struct mount *old, struct dentry *root,
static void mntput_no_expire(struct mount *mnt)
{
-put_again:
rcu_read_lock();
mnt_add_count(mnt, -1);
if (likely(mnt->mnt_ns)) { /* shouldn't be the last one */
@@ -964,14 +971,6 @@ static void mntput_no_expire(struct mount *mnt)
unlock_mount_hash();
return;
}
- if (unlikely(mnt->mnt_pinned)) {
- mnt_add_count(mnt, mnt->mnt_pinned + 1);
- mnt->mnt_pinned = 0;
- rcu_read_unlock();
- unlock_mount_hash();
- acct_auto_close_mnt(&mnt->mnt);
- goto put_again;
- }
if (unlikely(mnt->mnt.mnt_flags & MNT_DOOMED)) {
rcu_read_unlock();
unlock_mount_hash();
@@ -994,6 +993,8 @@ static void mntput_no_expire(struct mount *mnt)
* so mnt_get_writers() below is safe.
*/
WARN_ON(mnt_get_writers(mnt));
+ if (unlikely(mnt->mnt_pins.first))
+ mnt_pin_kill(mnt);
fsnotify_vfsmount_delete(&mnt->mnt);
dput(mnt->mnt.mnt_root);
deactivate_super(mnt->mnt.mnt_sb);
@@ -1021,25 +1022,15 @@ struct vfsmount *mntget(struct vfsmount *mnt)
}
EXPORT_SYMBOL(mntget);
-void mnt_pin(struct vfsmount *mnt)
-{
- lock_mount_hash();
- real_mount(mnt)->mnt_pinned++;
- unlock_mount_hash();
-}
-EXPORT_SYMBOL(mnt_pin);
-
-void mnt_unpin(struct vfsmount *m)
+struct vfsmount *mnt_clone_internal(struct path *path)
{
- struct mount *mnt = real_mount(m);
- lock_mount_hash();
- if (mnt->mnt_pinned) {
- mnt_add_count(mnt, 1);
- mnt->mnt_pinned--;
- }
- unlock_mount_hash();
+ struct mount *p;
+ p = clone_mnt(real_mount(path->mnt), path->dentry, CL_PRIVATE);
+ if (IS_ERR(p))
+ return ERR_CAST(p);
+ p->mnt.mnt_flags |= MNT_INTERNAL;
+ return &p->mnt;
}
-EXPORT_SYMBOL(mnt_unpin);
static inline void mangle(struct seq_file *m, const char *s)
{
@@ -1505,6 +1496,7 @@ struct mount *copy_tree(struct mount *mnt, struct dentry *dentry,
continue;
for (s = r; s; s = next_mnt(s, r)) {
+ struct mount *t = NULL;
if (!(flag & CL_COPY_UNBINDABLE) &&
IS_MNT_UNBINDABLE(s)) {
s = skip_mnt_tree(s);
@@ -1526,7 +1518,14 @@ struct mount *copy_tree(struct mount *mnt, struct dentry *dentry,
goto out;
lock_mount_hash();
list_add_tail(&q->mnt_list, &res->mnt_list);
- attach_mnt(q, parent, p->mnt_mp);
+ mnt_set_mountpoint(parent, p->mnt_mp, q);
+ if (!list_empty(&parent->mnt_mounts)) {
+ t = list_last_entry(&parent->mnt_mounts,
+ struct mount, mnt_child);
+ if (t->mnt_mp != p->mnt_mp)
+ t = NULL;
+ }
+ attach_shadowed(q, parent, t);
unlock_mount_hash();
}
}
diff --git a/fs/nfs/getroot.c b/fs/nfs/getroot.c
index b94f80420a584e596789fd048489463728a58789..880618a8b0489da1580e7cea0058de74ae2ceece 100644
--- a/fs/nfs/getroot.c
+++ b/fs/nfs/getroot.c
@@ -112,7 +112,7 @@ struct dentry *nfs_get_root(struct super_block *sb, struct nfs_fh *mntfh,
* if the dentry tree reaches them; however if the dentry already
* exists, we'll pick it up at this point and use it as the root
*/
- ret = d_obtain_alias(inode);
+ ret = d_obtain_root(inode);
if (IS_ERR(ret)) {
dprintk("nfs_get_root: get root dentry failed\n");
goto out;
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index c519927b7b5e8c955cf223cbd40924f648376ed2..228f5bdf07721dabae68349461eb1f24f99a2f33 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -942,7 +942,7 @@ static int nilfs_get_root_dentry(struct super_block *sb,
iput(inode);
}
} else {
- dentry = d_obtain_alias(inode);
+ dentry = d_obtain_root(inode);
if (IS_ERR(dentry)) {
ret = PTR_ERR(dentry);
goto failed_dentry;
diff --git a/fs/super.c b/fs/super.c
index d20d5b11dedf80a7d6c2f39872e6a892b21d7206..a371ce6aa91916f3efe1add1215b00001135a35a 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -22,7 +22,6 @@
#include <linux/export.h>
#include <linux/slab.h>
-#include <linux/acct.h>
#include <linux/blkdev.h>
#include <linux/mount.h>
#include <linux/security.h>
@@ -702,12 +701,22 @@ int do_remount_sb(struct super_block *sb, int flags, void *data, int force)
return -EACCES;
#endif
- if (flags & MS_RDONLY)
- acct_auto_close(sb);
- shrink_dcache_sb(sb);
-
remount_ro = (flags & MS_RDONLY) && !(sb->s_flags & MS_RDONLY);
+ if (remount_ro) {
+ if (sb->s_pins.first) {
+ up_write(&sb->s_umount);
+ sb_pin_kill(sb);
+ down_write(&sb->s_umount);
+ if (!sb->s_root)
+ return 0;
+ if (sb->s_writers.frozen != SB_UNFROZEN)
+ return -EBUSY;
+ remount_ro = (flags & MS_RDONLY) && !(sb->s_flags & MS_RDONLY);
+ }
+ }
+ shrink_dcache_sb(sb);
+
/* If we are remounting RDONLY and current sb is read/write,
make sure there are no rw files opened */
if (remount_ro) {
diff --git a/include/linux/acct.h b/include/linux/acct.h
index 4a5b7cb56079121152b780d7a75e54f43de4f344..dccc2d4fe7de690b30589334bf615d0e814590b5 100644
--- a/include/linux/acct.h
+++ b/include/linux/acct.h
@@ -24,14 +24,10 @@ struct super_block;
struct pacct_struct;
struct pid_namespace;
extern int acct_parm[]; /* for sysctl */
-extern void acct_auto_close_mnt(struct vfsmount *m);
-extern void acct_auto_close(struct super_block *sb);
extern void acct_collect(long exitcode, int group_dead);
extern void acct_process(void);
extern void acct_exit_ns(struct pid_namespace *);
#else
-#define acct_auto_close_mnt(x) do { } while (0)
-#define acct_auto_close(x) do { } while (0)
#define acct_collect(x,y) do { } while (0)
#define acct_process() do { } while (0)
#define acct_exit_ns(ns) do { } while (0)
diff --git a/include/linux/dcache.h b/include/linux/dcache.h
index 3c7ec327ebd2eecc2fb63ac4f742ca0d75c56ec8..e4ae2ad48d072efcd78e3905c3f1e212130c88cc 100644
--- a/include/linux/dcache.h
+++ b/include/linux/dcache.h
@@ -249,6 +249,7 @@ extern struct dentry * d_splice_alias(struct inode *, struct dentry *);
extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *);
extern struct dentry *d_find_any_alias(struct inode *inode);
extern struct dentry * d_obtain_alias(struct inode *);
+extern struct dentry * d_obtain_root(struct inode *);
extern void shrink_dcache_sb(struct super_block *);
extern void shrink_dcache_parent(struct dentry *);
extern void shrink_dcache_for_umount(struct super_block *);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index f0890e4a7c25755c9531cb5903aa8e084043d2c8..94187721ad412c6c8da4b44e946d24ecd240beb0 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1275,6 +1275,7 @@ struct super_block {
/* AIO completions deferred from interrupt context */
struct workqueue_struct *s_dio_done_wq;
+ struct hlist_head s_pins;
/*
* Keep the lru lists last in the structure so they always sit on their
@@ -2360,6 +2361,7 @@ extern int do_pipe_flags(int *, int);
extern int kernel_read(struct file *, loff_t, char *, unsigned long);
extern ssize_t kernel_write(struct file *, const char *, size_t, loff_t);
+extern ssize_t __kernel_write(struct file *, const char *, size_t, loff_t *);
extern struct file * open_exec(const char *);
/* fs/dcache.c -- generic fs support functions */
diff --git a/include/linux/fs_pin.h b/include/linux/fs_pin.h
new file mode 100644
index 0000000000000000000000000000000000000000..f66525e72ccf1a4002df46354a9e59927b5f821d
--- /dev/null
+++ b/include/linux/fs_pin.h
@@ -0,0 +1,17 @@
+#include <linux/fs.h>
+
+struct fs_pin {
+ atomic_long_t count;
+ union {
+ struct {
+ struct hlist_node s_list;
+ struct hlist_node m_list;
+ };
+ struct rcu_head rcu;
+ };
+ void (*kill)(struct fs_pin *);
+};
+
+void pin_put(struct fs_pin *);
+void pin_remove(struct fs_pin *);
+void pin_insert(struct fs_pin *, struct vfsmount *);
diff --git a/include/linux/mount.h b/include/linux/mount.h
index b0c1e6574e7fc7f5ff204fb39a12cfe1cb751268..9262e4bf0cc3408588adc819abc7ea9be69b88dd 100644
--- a/include/linux/mount.h
+++ b/include/linux/mount.h
@@ -69,6 +69,7 @@ struct vfsmount {
};
struct file; /* forward dec */
+struct path;
extern int mnt_want_write(struct vfsmount *mnt);
extern int mnt_want_write_file(struct file *file);
@@ -77,8 +78,7 @@ extern void mnt_drop_write(struct vfsmount *mnt);
extern void mnt_drop_write_file(struct file *file);
extern void mntput(struct vfsmount *mnt);
extern struct vfsmount *mntget(struct vfsmount *mnt);
-extern void mnt_pin(struct vfsmount *mnt);
-extern void mnt_unpin(struct vfsmount *mnt);
+extern struct vfsmount *mnt_clone_internal(struct path *path);
extern int __mnt_is_readonly(struct vfsmount *mnt);
struct file_system_type;
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 09a7cffc224e2d8293d747255db856427e105925..48d64e6ab29279a5d46e57114b8272b7a2069c4f 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,
- size_t maxsize, size_t *start);
+ 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/kernel/acct.c b/kernel/acct.c
index 51793520566fade30ec645d0cdd74d31f4c369ed..b4c667d22e7930968dfd65f7f6b5f6924f52f5bd 100644
--- a/kernel/acct.c
+++ b/kernel/acct.c
@@ -59,6 +59,7 @@
#include <asm/div64.h>
#include <linux/blkdev.h> /* sector_div */
#include <linux/pid_namespace.h>
+#include <linux/fs_pin.h>
/*
* These constants control the amount of freespace that suspend and
@@ -75,172 +76,190 @@ int acct_parm[3] = {4, 2, 30};
/*
* External references and all of the globals.
*/
-static void do_acct_process(struct bsd_acct_struct *acct,
- struct pid_namespace *ns, struct file *);
+static void do_acct_process(struct bsd_acct_struct *acct);
-/*
- * This structure is used so that all the data protected by lock
- * can be placed in the same cache line as the lock. This primes
- * the cache line to have the data after getting the lock.
- */
struct bsd_acct_struct {
+ struct fs_pin pin;
+ struct mutex lock;
int active;
unsigned long needcheck;
struct file *file;
struct pid_namespace *ns;
- struct list_head list;
+ struct work_struct work;
+ struct completion done;
};
-static DEFINE_SPINLOCK(acct_lock);
-static LIST_HEAD(acct_list);
-
/*
* Check the amount of free space and suspend/resume accordingly.
*/
-static int check_free_space(struct bsd_acct_struct *acct, struct file *file)
+static int check_free_space(struct bsd_acct_struct *acct)
{
struct kstatfs sbuf;
- int res;
- int act;
- u64 resume;
- u64 suspend;
-
- spin_lock(&acct_lock);
- res = acct->active;
- if (!file || time_is_before_jiffies(acct->needcheck))
+
+ if (time_is_before_jiffies(acct->needcheck))
goto out;
- spin_unlock(&acct_lock);
/* May block */
- if (vfs_statfs(&file->f_path, &sbuf))
- return res;
- suspend = sbuf.f_blocks * SUSPEND;
- resume = sbuf.f_blocks * RESUME;
-
- do_div(suspend, 100);
- do_div(resume, 100);
-
- if (sbuf.f_bavail <= suspend)
- act = -1;
- else if (sbuf.f_bavail >= resume)
- act = 1;
- else
- act = 0;
-
- /*
- * If some joker switched acct->file under us we'ld better be
- * silent and _not_ touch anything.
- */
- spin_lock(&acct_lock);
- if (file != acct->file) {
- if (act)
- res = act > 0;
+ if (vfs_statfs(&acct->file->f_path, &sbuf))
goto out;
- }
if (acct->active) {
- if (act < 0) {
+ u64 suspend = sbuf.f_blocks * SUSPEND;
+ do_div(suspend, 100);
+ if (sbuf.f_bavail <= suspend) {
acct->active = 0;
pr_info("Process accounting paused\n");
}
} else {
- if (act > 0) {
+ u64 resume = sbuf.f_blocks * RESUME;
+ do_div(resume, 100);
+ if (sbuf.f_bavail >= resume) {
acct->active = 1;
pr_info("Process accounting resumed\n");
}
}
acct->needcheck = jiffies + ACCT_TIMEOUT*HZ;
- res = acct->active;
out:
- spin_unlock(&acct_lock);
+ return acct->active;
+}
+
+static struct bsd_acct_struct *acct_get(struct pid_namespace *ns)
+{
+ struct bsd_acct_struct *res;
+again:
+ smp_rmb();
+ rcu_read_lock();
+ res = ACCESS_ONCE(ns->bacct);
+ if (!res) {
+ rcu_read_unlock();
+ return NULL;
+ }
+ if (!atomic_long_inc_not_zero(&res->pin.count)) {
+ rcu_read_unlock();
+ cpu_relax();
+ goto again;
+ }
+ rcu_read_unlock();
+ mutex_lock(&res->lock);
+ if (!res->ns) {
+ mutex_unlock(&res->lock);
+ pin_put(&res->pin);
+ goto again;
+ }
return res;
}
-/*
- * Close the old accounting file (if currently open) and then replace
- * it with file (if non-NULL).
- *
- * NOTE: acct_lock MUST be held on entry and exit.
- */
-static void acct_file_reopen(struct bsd_acct_struct *acct, struct file *file,
- struct pid_namespace *ns)
+static void close_work(struct work_struct *work)
{
- struct file *old_acct = NULL;
- struct pid_namespace *old_ns = NULL;
-
- if (acct->file) {
- old_acct = acct->file;
- old_ns = acct->ns;
- acct->active = 0;
- acct->file = NULL;
+ struct bsd_acct_struct *acct = container_of(work, struct bsd_acct_struct, work);
+ struct file *file = acct->file;
+ if (file->f_op->flush)
+ file->f_op->flush(file, NULL);
+ __fput_sync(file);
+ complete(&acct->done);
+}
+
+static void acct_kill(struct bsd_acct_struct *acct,
+ struct bsd_acct_struct *new)
+{
+ if (acct) {
+ struct pid_namespace *ns = acct->ns;
+ do_acct_process(acct);
+ INIT_WORK(&acct->work, close_work);
+ init_completion(&acct->done);
+ schedule_work(&acct->work);
+ wait_for_completion(&acct->done);
+ pin_remove(&acct->pin);
+ ns->bacct = new;
acct->ns = NULL;
- list_del(&acct->list);
- }
- if (file) {
- acct->file = file;
- acct->ns = ns;
- acct->needcheck = jiffies + ACCT_TIMEOUT*HZ;
- acct->active = 1;
- list_add(&acct->list, &acct_list);
+ atomic_long_dec(&acct->pin.count);
+ mutex_unlock(&acct->lock);
+ pin_put(&acct->pin);
}
- if (old_acct) {
- mnt_unpin(old_acct->f_path.mnt);
- spin_unlock(&acct_lock);
- do_acct_process(acct, old_ns, old_acct);
- filp_close(old_acct, NULL);
- spin_lock(&acct_lock);
+}
+
+static void acct_pin_kill(struct fs_pin *pin)
+{
+ struct bsd_acct_struct *acct;
+ acct = container_of(pin, struct bsd_acct_struct, pin);
+ mutex_lock(&acct->lock);
+ if (!acct->ns) {
+ mutex_unlock(&acct->lock);
+ pin_put(pin);
+ acct = NULL;
}
+ acct_kill(acct, NULL);
}
static int acct_on(struct filename *pathname)
{
struct file *file;
- struct vfsmount *mnt;
- struct pid_namespace *ns;
- struct bsd_acct_struct *acct = NULL;
+ struct vfsmount *mnt, *internal;
+ struct pid_namespace *ns = task_active_pid_ns(current);
+ struct bsd_acct_struct *acct, *old;
+ int err;
+
+ acct = kzalloc(sizeof(struct bsd_acct_struct), GFP_KERNEL);
+ if (!acct)
+ return -ENOMEM;
/* Difference from BSD - they don't do O_APPEND */
file = file_open_name(pathname, O_WRONLY|O_APPEND|O_LARGEFILE, 0);
- if (IS_ERR(file))
+ if (IS_ERR(file)) {
+ kfree(acct);
return PTR_ERR(file);
+ }
if (!S_ISREG(file_inode(file)->i_mode)) {
+ kfree(acct);
filp_close(file, NULL);
return -EACCES;
}
if (!file->f_op->write) {
+ kfree(acct);
filp_close(file, NULL);
return -EIO;
}
-
- ns = task_active_pid_ns(current);
- if (ns->bacct == NULL) {
- acct = kzalloc(sizeof(struct bsd_acct_struct), GFP_KERNEL);
- if (acct == NULL) {
- filp_close(file, NULL);
- return -ENOMEM;
- }
+ internal = mnt_clone_internal(&file->f_path);
+ if (IS_ERR(internal)) {
+ kfree(acct);
+ filp_close(file, NULL);
+ return PTR_ERR(internal);
}
-
- spin_lock(&acct_lock);
- if (ns->bacct == NULL) {
- ns->bacct = acct;
- acct = NULL;
+ err = mnt_want_write(internal);
+ if (err) {
+ mntput(internal);
+ kfree(acct);
+ filp_close(file, NULL);
+ return err;
}
-
mnt = file->f_path.mnt;
- mnt_pin(mnt);
- acct_file_reopen(ns->bacct, file, ns);
- spin_unlock(&acct_lock);
-
- mntput(mnt); /* it's pinned, now give up active reference */
- kfree(acct);
-
+ file->f_path.mnt = internal;
+
+ atomic_long_set(&acct->pin.count, 1);
+ acct->pin.kill = acct_pin_kill;
+ acct->file = file;
+ acct->needcheck = jiffies;
+ acct->ns = ns;
+ mutex_init(&acct->lock);
+ mutex_lock_nested(&acct->lock, 1); /* nobody has seen it yet */
+ pin_insert(&acct->pin, mnt);
+
+ old = acct_get(ns);
+ if (old)
+ acct_kill(old, acct);
+ else
+ ns->bacct = acct;
+ mutex_unlock(&acct->lock);
+ mnt_drop_write(mnt);
+ mntput(mnt);
return 0;
}
+static DEFINE_MUTEX(acct_on_mutex);
+
/**
* sys_acct - enable/disable process accounting
* @name: file name for accounting records or NULL to shutdown accounting
@@ -264,78 +283,20 @@ SYSCALL_DEFINE1(acct, const char __user *, name)
if (IS_ERR(tmp))
return PTR_ERR(tmp);
+ mutex_lock(&acct_on_mutex);
error = acct_on(tmp);
+ mutex_unlock(&acct_on_mutex);
putname(tmp);
} else {
- struct bsd_acct_struct *acct;
-
- acct = task_active_pid_ns(current)->bacct;
- if (acct == NULL)
- return 0;
-
- spin_lock(&acct_lock);
- acct_file_reopen(acct, NULL, NULL);
- spin_unlock(&acct_lock);
+ acct_kill(acct_get(task_active_pid_ns(current)), NULL);
}
return error;
}
-/**
- * acct_auto_close - turn off a filesystem's accounting if it is on
- * @m: vfsmount being shut down
- *
- * If the accounting is turned on for a file in the subtree pointed to
- * to by m, turn accounting off. Done when m is about to die.
- */
-void acct_auto_close_mnt(struct vfsmount *m)
-{
- struct bsd_acct_struct *acct;
-
- spin_lock(&acct_lock);
-restart:
- list_for_each_entry(acct, &acct_list, list)
- if (acct->file && acct->file->f_path.mnt == m) {
- acct_file_reopen(acct, NULL, NULL);
- goto restart;
- }
- spin_unlock(&acct_lock);
-}
-
-/**
- * acct_auto_close - turn off a filesystem's accounting if it is on
- * @sb: super block for the filesystem
- *
- * If the accounting is turned on for a file in the filesystem pointed
- * to by sb, turn accounting off.
- */
-void acct_auto_close(struct super_block *sb)
-{
- struct bsd_acct_struct *acct;
-
- spin_lock(&acct_lock);
-restart:
- list_for_each_entry(acct, &acct_list, list)
- if (acct->file && acct->file->f_path.dentry->d_sb == sb) {
- acct_file_reopen(acct, NULL, NULL);
- goto restart;
- }
- spin_unlock(&acct_lock);
-}
-
void acct_exit_ns(struct pid_namespace *ns)
{
- struct bsd_acct_struct *acct = ns->bacct;
-
- if (acct == NULL)
- return;
-
- spin_lock(&acct_lock);
- if (acct->file != NULL)
- acct_file_reopen(acct, NULL, NULL);
- spin_unlock(&acct_lock);
-
- kfree(acct);
+ acct_kill(acct_get(ns), NULL);
}
/*
@@ -450,38 +411,20 @@ static u32 encode_float(u64 value)
* do_exit() or when switching to a different output file.
*/
-/*
- * do_acct_process does all actual work. Caller holds the reference to file.
- */
-static void do_acct_process(struct bsd_acct_struct *acct,
- struct pid_namespace *ns, struct file *file)
+static void fill_ac(acct_t *ac)
{
struct pacct_struct *pacct = ¤t->signal->pacct;
- acct_t ac;
- mm_segment_t fs;
- unsigned long flim;
u64 elapsed, run_time;
struct tty_struct *tty;
- const struct cred *orig_cred;
-
- /* Perform file operations on behalf of whoever enabled accounting */
- orig_cred = override_creds(file->f_cred);
-
- /*
- * First check to see if there is enough free_space to continue
- * the process accounting system.
- */
- if (!check_free_space(acct, file))
- goto out;
/*
* Fill the accounting struct with the needed info as recorded
* by the different kernel functions.
*/
- memset(&ac, 0, sizeof(acct_t));
+ memset(ac, 0, sizeof(acct_t));
- ac.ac_version = ACCT_VERSION | ACCT_BYTEORDER;
- strlcpy(ac.ac_comm, current->comm, sizeof(ac.ac_comm));
+ ac->ac_version = ACCT_VERSION | ACCT_BYTEORDER;
+ strlcpy(ac->ac_comm, current->comm, sizeof(ac->ac_comm));
/* calculate run_time in nsec*/
run_time = ktime_get_ns();
@@ -489,9 +432,9 @@ static void do_acct_process(struct bsd_acct_struct *acct,
/* convert nsec -> AHZ */
elapsed = nsec_to_AHZ(run_time);
#if ACCT_VERSION == 3
- ac.ac_etime = encode_float(elapsed);
+ ac->ac_etime = encode_float(elapsed);
#else
- ac.ac_etime = encode_comp_t(elapsed < (unsigned long) -1l ?
+ ac->ac_etime = encode_comp_t(elapsed < (unsigned long) -1l ?
(unsigned long) elapsed : (unsigned long) -1l);
#endif
#if ACCT_VERSION == 1 || ACCT_VERSION == 2
@@ -499,18 +442,58 @@ static void do_acct_process(struct bsd_acct_struct *acct,
/* new enlarged etime field */
comp2_t etime = encode_comp2_t(elapsed);
- ac.ac_etime_hi = etime >> 16;
- ac.ac_etime_lo = (u16) etime;
+ ac->ac_etime_hi = etime >> 16;
+ ac->ac_etime_lo = (u16) etime;
}
#endif
do_div(elapsed, AHZ);
- ac.ac_btime = get_seconds() - elapsed;
+ ac->ac_btime = get_seconds() - elapsed;
+#if ACCT_VERSION==2
+ ac->ac_ahz = AHZ;
+#endif
+
+ spin_lock_irq(¤t->sighand->siglock);
+ tty = current->signal->tty; /* Safe as we hold the siglock */
+ ac->ac_tty = tty ? old_encode_dev(tty_devnum(tty)) : 0;
+ ac->ac_utime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime)));
+ ac->ac_stime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime)));
+ ac->ac_flag = pacct->ac_flag;
+ ac->ac_mem = encode_comp_t(pacct->ac_mem);
+ ac->ac_minflt = encode_comp_t(pacct->ac_minflt);
+ ac->ac_majflt = encode_comp_t(pacct->ac_majflt);
+ ac->ac_exitcode = pacct->ac_exitcode;
+ spin_unlock_irq(¤t->sighand->siglock);
+}
+/*
+ * do_acct_process does all actual work. Caller holds the reference to file.
+ */
+static void do_acct_process(struct bsd_acct_struct *acct)
+{
+ acct_t ac;
+ unsigned long flim;
+ const struct cred *orig_cred;
+ struct pid_namespace *ns = acct->ns;
+ struct file *file = acct->file;
+
+ /*
+ * Accounting records are not subject to resource limits.
+ */
+ flim = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
+ current->signal->rlim[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
+ /* Perform file operations on behalf of whoever enabled accounting */
+ orig_cred = override_creds(file->f_cred);
+
+ /*
+ * First check to see if there is enough free_space to continue
+ * the process accounting system.
+ */
+ if (!check_free_space(acct))
+ goto out;
+
+ fill_ac(&ac);
/* we really need to bite the bullet and change layout */
ac.ac_uid = from_kuid_munged(file->f_cred->user_ns, orig_cred->uid);
ac.ac_gid = from_kgid_munged(file->f_cred->user_ns, orig_cred->gid);
-#if ACCT_VERSION == 2
- ac.ac_ahz = AHZ;
-#endif
#if ACCT_VERSION == 1 || ACCT_VERSION == 2
/* backward-compatible 16 bit fields */
ac.ac_uid16 = ac.ac_uid;
@@ -522,45 +505,18 @@ static void do_acct_process(struct bsd_acct_struct *acct,
ac.ac_ppid = task_tgid_nr_ns(rcu_dereference(current->real_parent), ns);
rcu_read_unlock();
#endif
-
- spin_lock_irq(¤t->sighand->siglock);
- tty = current->signal->tty; /* Safe as we hold the siglock */
- ac.ac_tty = tty ? old_encode_dev(tty_devnum(tty)) : 0;
- ac.ac_utime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime)));
- ac.ac_stime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime)));
- ac.ac_flag = pacct->ac_flag;
- ac.ac_mem = encode_comp_t(pacct->ac_mem);
- ac.ac_minflt = encode_comp_t(pacct->ac_minflt);
- ac.ac_majflt = encode_comp_t(pacct->ac_majflt);
- ac.ac_exitcode = pacct->ac_exitcode;
- spin_unlock_irq(¤t->sighand->siglock);
- ac.ac_io = encode_comp_t(0 /* current->io_usage */); /* %% */
- ac.ac_rw = encode_comp_t(ac.ac_io / 1024);
- ac.ac_swaps = encode_comp_t(0);
-
/*
* Get freeze protection. If the fs is frozen, just skip the write
* as we could deadlock the system otherwise.
*/
- if (!file_start_write_trylock(file))
- goto out;
- /*
- * Kernel segment override to datasegment and write it
- * to the accounting file.
- */
- fs = get_fs();
- set_fs(KERNEL_DS);
- /*
- * Accounting records are not subject to resource limits.
- */
- flim = current->signal->rlim[RLIMIT_FSIZE].rlim_cur;
- current->signal->rlim[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
- file->f_op->write(file, (char *)&ac,
- sizeof(acct_t), &file->f_pos);
- current->signal->rlim[RLIMIT_FSIZE].rlim_cur = flim;
- set_fs(fs);
- file_end_write(file);
+ if (file_start_write_trylock(file)) {
+ /* it's been opened O_APPEND, so position is irrelevant */
+ loff_t pos = 0;
+ __kernel_write(file, (char *)&ac, sizeof(acct_t), &pos);
+ file_end_write(file);
+ }
out:
+ current->signal->rlim[RLIMIT_FSIZE].rlim_cur = flim;
revert_creds(orig_cred);
}
@@ -609,34 +565,20 @@ void acct_collect(long exitcode, int group_dead)
spin_unlock_irq(¤t->sighand->siglock);
}
-static void acct_process_in_ns(struct pid_namespace *ns)
+static void slow_acct_process(struct pid_namespace *ns)
{
- struct file *file = NULL;
- struct bsd_acct_struct *acct;
-
- acct = ns->bacct;
- /*
- * accelerate the common fastpath:
- */
- if (!acct || !acct->file)
- return;
-
- spin_lock(&acct_lock);
- file = acct->file;
- if (unlikely(!file)) {
- spin_unlock(&acct_lock);
- return;
+ for ( ; ns; ns = ns->parent) {
+ struct bsd_acct_struct *acct = acct_get(ns);
+ if (acct) {
+ do_acct_process(acct);
+ mutex_unlock(&acct->lock);
+ pin_put(&acct->pin);
+ }
}
- get_file(file);
- spin_unlock(&acct_lock);
-
- do_acct_process(acct, ns, file);
- fput(file);
}
/**
- * acct_process - now just a wrapper around acct_process_in_ns,
- * which in turn is a wrapper around do_acct_process.
+ * acct_process
*
* handles process accounting for an exiting task
*/
@@ -649,6 +591,10 @@ void acct_process(void)
* alive and holds its namespace, which in turn holds
* its parent.
*/
- for (ns = task_active_pid_ns(current); ns != NULL; ns = ns->parent)
- acct_process_in_ns(ns);
+ for (ns = task_active_pid_ns(current); ns != NULL; ns = ns->parent) {
+ if (ns->bacct)
+ break;
+ }
+ if (unlikely(ns))
+ slow_acct_process(ns);
}
diff --git a/mm/filemap.c b/mm/filemap.c
index f501b56ec2c6e2c3d3c662669afbffc9017797b5..90effcdf948d6c463afa817e277e7eae94b657a6 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2602,7 +2602,7 @@ ssize_t __generic_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
* that this differs from normal direct-io semantics, which
* will return -EFOO even if some bytes were written.
*/
- if (unlikely(status < 0) && !written) {
+ if (unlikely(status < 0)) {
err = status;
goto out;
}
diff --git a/mm/iov_iter.c b/mm/iov_iter.c
index 7b5dbd1517b5594b05d5590cae29c3eb3a1dada2..ab88dc0ea1d36a3a7e971f096e8e10c4a1646c93 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, size_t maxsize,
+ struct page **pages, unsigned maxpages,
size_t *start)
{
size_t offset = i->iov_offset;
@@ -323,10 +323,10 @@ 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)
+ len = maxpages * PAGE_SIZE;
addr &= ~(PAGE_SIZE - 1);
n = (len + PAGE_SIZE - 1) / PAGE_SIZE;
res = get_user_pages_fast(addr, n, (i->type & WRITE) != WRITE, pages);
@@ -588,15 +588,14 @@ static unsigned long alignment_bvec(const struct iov_iter *i)
}
static ssize_t get_pages_bvec(struct iov_iter *i,
- struct page **pages, size_t maxsize,
+ struct page **pages, 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;
get_page(*pages = bvec->bv_page);
@@ -712,13 +711,13 @@ 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, size_t maxsize,
+ struct page **pages, unsigned maxpages,
size_t *start)
{
if (i->type & ITER_BVEC)
- return get_pages_bvec(i, pages, maxsize, start);
+ return get_pages_bvec(i, pages, maxpages, start);
else
- return get_pages_iovec(i, pages, maxsize, start);
+ return get_pages_iovec(i, pages, maxpages, start);
}
EXPORT_SYMBOL(iov_iter_get_pages);
diff --git a/mm/shmem.c b/mm/shmem.c
index a42add14331c02171f5f3fbb30ed4e82b8d9fad3..0e5fb225007c519a27b680673160011bd74dd445 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2323,17 +2323,45 @@ static int shmem_rmdir(struct inode *dir, struct dentry *dentry)
return shmem_unlink(dir, dentry);
}
+static int shmem_exchange(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry)
+{
+ bool old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
+ bool new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
+
+ if (old_dir != new_dir && old_is_dir != new_is_dir) {
+ if (old_is_dir) {
+ drop_nlink(old_dir);
+ inc_nlink(new_dir);
+ } else {
+ drop_nlink(new_dir);
+ inc_nlink(old_dir);
+ }
+ }
+ old_dir->i_ctime = old_dir->i_mtime =
+ new_dir->i_ctime = new_dir->i_mtime =
+ old_dentry->d_inode->i_ctime =
+ new_dentry->d_inode->i_ctime = CURRENT_TIME;
+
+ return 0;
+}
+
/*
* The VFS layer already does all the dentry stuff for rename,
* we just have to decrement the usage count for the target if
* it exists so that the VFS layer correctly free's it when it
* gets overwritten.
*/
-static int shmem_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry)
+static int shmem_rename2(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry, unsigned int flags)
{
struct inode *inode = old_dentry->d_inode;
int they_are_dirs = S_ISDIR(inode->i_mode);
+ if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
+ return -EINVAL;
+
+ if (flags & RENAME_EXCHANGE)
+ return shmem_exchange(old_dir, old_dentry, new_dir, new_dentry);
+
if (!simple_empty(new_dentry))
return -ENOTEMPTY;
@@ -3087,7 +3115,7 @@ static const struct inode_operations shmem_dir_inode_operations = {
.mkdir = shmem_mkdir,
.rmdir = shmem_rmdir,
.mknod = shmem_mknod,
- .rename = shmem_rename,
+ .rename2 = shmem_rename2,
.tmpfile = shmem_tmpfile,
#endif
#ifdef CONFIG_TMPFS_XATTR