summaryrefslogtreecommitdiff
path: root/fs/open.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2018-08-21 18:19:09 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-21 18:19:09 -0700
commitd9a185f8b49678775ef56ecbdbc7b76970302897 (patch)
tree7ace1b26133e5d796af09e5d71d6531bcb69865c /fs/open.c
parentc22fc16d172fba4d19ffd8f2aa8fe67edba63895 (diff)
parent989974c804574d250ac92d44e220081959ac8ac1 (diff)
Merge tag 'ovl-update-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs updates from Miklos Szeredi: "This contains two new features: - Stack file operations: this allows removal of several hacks from the VFS, proper interaction of read-only open files with copy-up, possibility to implement fs modifying ioctls properly, and others. - Metadata only copy-up: when file is on lower layer and only metadata is modified (except size) then only copy up the metadata and continue to use the data from the lower file" * tag 'ovl-update-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: (66 commits) ovl: Enable metadata only feature ovl: Do not do metacopy only for ioctl modifying file attr ovl: Do not do metadata only copy-up for truncate operation ovl: add helper to force data copy-up ovl: Check redirect on index as well ovl: Set redirect on upper inode when it is linked ovl: Set redirect on metacopy files upon rename ovl: Do not set dentry type ORIGIN for broken hardlinks ovl: Add an inode flag OVL_CONST_INO ovl: Treat metacopy dentries as type OVL_PATH_MERGE ovl: Check redirects for metacopy files ovl: Move some dir related ovl_lookup_single() code in else block ovl: Do not expose metacopy only dentry from d_real() ovl: Open file with data except for the case of fsync ovl: Add helper ovl_inode_realdata() ovl: Store lower data inode in ovl_inode ovl: Fix ovl_getattr() to get number of blocks from lower ovl: Add helper ovl_dentry_lowerdata() to get lower data dentry ovl: Copy up meta inode data from lowest data inode ovl: Modify ovl_lookup() and friends to lookup metacopy dentry ...
Diffstat (limited to 'fs/open.c')
-rw-r--r--fs/open.c44
1 files changed, 23 insertions, 21 deletions
diff --git a/fs/open.c b/fs/open.c
index d98e19239bb7..0285ce7dbd51 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -68,7 +68,6 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
long vfs_truncate(const struct path *path, loff_t length)
{
struct inode *inode;
- struct dentry *upperdentry;
long error;
inode = path->dentry->d_inode;
@@ -91,17 +90,7 @@ long vfs_truncate(const struct path *path, loff_t length)
if (IS_APPEND(inode))
goto mnt_drop_write_and_out;
- /*
- * If this is an overlayfs then do as if opening the file so we get
- * write access on the upper inode, not on the overlay inode. For
- * non-overlay filesystems d_real() is an identity function.
- */
- upperdentry = d_real(path->dentry, NULL, O_WRONLY, 0);
- error = PTR_ERR(upperdentry);
- if (IS_ERR(upperdentry))
- goto mnt_drop_write_and_out;
-
- error = get_write_access(upperdentry->d_inode);
+ error = get_write_access(inode);
if (error)
goto mnt_drop_write_and_out;
@@ -120,7 +109,7 @@ long vfs_truncate(const struct path *path, loff_t length)
error = do_truncate(path->dentry, length, 0, NULL);
put_write_and_out:
- put_write_access(upperdentry->d_inode);
+ put_write_access(inode);
mnt_drop_write_and_out:
mnt_drop_write(path->mnt);
out:
@@ -707,12 +696,12 @@ int ksys_fchown(unsigned int fd, uid_t user, gid_t group)
if (!f.file)
goto out;
- error = mnt_want_write_file_path(f.file);
+ error = mnt_want_write_file(f.file);
if (error)
goto out_fput;
audit_file(f.file);
error = chown_common(&f.file->f_path, user, group);
- mnt_drop_write_file_path(f.file);
+ mnt_drop_write_file(f.file);
out_fput:
fdput(f);
out:
@@ -887,13 +876,8 @@ EXPORT_SYMBOL(file_path);
*/
int vfs_open(const struct path *path, struct file *file)
{
- struct dentry *dentry = d_real(path->dentry, NULL, file->f_flags, 0);
-
- if (IS_ERR(dentry))
- return PTR_ERR(dentry);
-
file->f_path = *path;
- return do_dentry_open(file, d_backing_inode(dentry), NULL);
+ return do_dentry_open(file, d_backing_inode(path->dentry), NULL);
}
struct file *dentry_open(const struct path *path, int flags,
@@ -919,6 +903,24 @@ struct file *dentry_open(const struct path *path, int flags,
}
EXPORT_SYMBOL(dentry_open);
+struct file *open_with_fake_path(const struct path *path, int flags,
+ struct inode *inode, const struct cred *cred)
+{
+ struct file *f = alloc_empty_file_noaccount(flags, cred);
+ if (!IS_ERR(f)) {
+ int error;
+
+ f->f_path = *path;
+ error = do_dentry_open(f, inode, NULL);
+ if (error) {
+ fput(f);
+ f = ERR_PTR(error);
+ }
+ }
+ return f;
+}
+EXPORT_SYMBOL(open_with_fake_path);
+
static inline int build_open_flags(int flags, umode_t mode, struct open_flags *op)
{
int lookup_flags = 0;