Stop using struct fd to return a real file from ovl_real_fdget(),
because we no longer return a temporary file object and the callers
always get a borrowed file reference.
Rename the helper to ovl_real_file(), return a borrowed reference of
the real file that is referenced from the overlayfs file or an error.
Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
---
fs/overlayfs/file.c | 145 ++++++++++++++++++--------------------------
1 file changed, 59 insertions(+), 86 deletions(-)
diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index b6d6ccc39dad..b7bec2adb575 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -176,16 +176,6 @@ static struct file *ovl_real_file(const struct file *file)
return ovl_real_file_path(file, &realpath);
}
-static int ovl_real_fdget(const struct file *file, struct fd *real)
-{
- struct file *f = ovl_real_file(file);
-
- if (IS_ERR(f))
- return PTR_ERR(f);
- real->word = (unsigned long)f;
- return 0;
-}
-
static struct file *ovl_upper_file(const struct file *file, bool data)
{
struct dentry *dentry = file_dentry(file);
@@ -259,7 +249,7 @@ static int ovl_release(struct inode *inode, struct file *file)
static loff_t ovl_llseek(struct file *file, loff_t offset, int whence)
{
struct inode *inode = file_inode(file);
- struct fd real;
+ struct file *realfile;
const struct cred *old_cred;
loff_t ret;
@@ -275,9 +265,9 @@ static loff_t ovl_llseek(struct file *file, loff_t offset, int whence)
return vfs_setpos(file, 0, 0);
}
- ret = ovl_real_fdget(file, &real);
- if (ret)
- return ret;
+ realfile = ovl_real_file(file);
+ if (IS_ERR(realfile))
+ return PTR_ERR(realfile);
/*
* Overlay file f_pos is the master copy that is preserved
@@ -287,17 +277,15 @@ static loff_t ovl_llseek(struct file *file, loff_t offset, int whence)
* files, so we use the real file to perform seeks.
*/
ovl_inode_lock(inode);
- fd_file(real)->f_pos = file->f_pos;
+ realfile->f_pos = file->f_pos;
old_cred = ovl_override_creds(inode->i_sb);
- ret = vfs_llseek(fd_file(real), offset, whence);
+ ret = vfs_llseek(realfile, offset, whence);
revert_creds(old_cred);
- file->f_pos = fd_file(real)->f_pos;
+ file->f_pos = realfile->f_pos;
ovl_inode_unlock(inode);
- fdput(real);
-
return ret;
}
@@ -338,8 +326,7 @@ static void ovl_file_accessed(struct file *file)
static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter)
{
struct file *file = iocb->ki_filp;
- struct fd real;
- ssize_t ret;
+ struct file *realfile;
struct backing_file_ctx ctx = {
.cred = ovl_creds(file_inode(file)->i_sb),
.user_file = file,
@@ -349,22 +336,19 @@ static ssize_t ovl_read_iter(struct kiocb *iocb, struct iov_iter *iter)
if (!iov_iter_count(iter))
return 0;
- ret = ovl_real_fdget(file, &real);
- if (ret)
- return ret;
-
- ret = backing_file_read_iter(fd_file(real), iter, iocb, iocb->ki_flags,
- &ctx);
- fdput(real);
+ realfile = ovl_real_file(file);
+ if (IS_ERR(realfile))
+ return PTR_ERR(realfile);
- return ret;
+ return backing_file_read_iter(realfile, iter, iocb, iocb->ki_flags,
+ &ctx);
}
static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file_inode(file);
- struct fd real;
+ struct file *realfile;
ssize_t ret;
int ifl = iocb->ki_flags;
struct backing_file_ctx ctx = {
@@ -380,8 +364,9 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter)
/* Update mode */
ovl_copyattr(inode);
- ret = ovl_real_fdget(file, &real);
- if (ret)
+ realfile = ovl_real_file(file);
+ ret = PTR_ERR(realfile);
+ if (IS_ERR(realfile))
goto out_unlock;
if (!ovl_should_sync(OVL_FS(inode->i_sb)))
@@ -392,8 +377,7 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter)
* this property in case it is set by the issuer.
*/
ifl &= ~IOCB_DIO_CALLER_COMP;
- ret = backing_file_write_iter(fd_file(real), iter, iocb, ifl, &ctx);
- fdput(real);
+ ret = backing_file_write_iter(realfile, iter, iocb, ifl, &ctx);
out_unlock:
inode_unlock(inode);
@@ -405,28 +389,24 @@ static ssize_t ovl_splice_read(struct file *in, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags)
{
- struct fd real;
- ssize_t ret;
+ struct file *realfile;
struct backing_file_ctx ctx = {
.cred = ovl_creds(file_inode(in)->i_sb),
.user_file = in,
.accessed = ovl_file_accessed,
};
- ret = ovl_real_fdget(in, &real);
- if (ret)
- return ret;
-
- ret = backing_file_splice_read(fd_file(real), ppos, pipe, len, flags, &ctx);
- fdput(real);
+ realfile = ovl_real_file(in);
+ if (IS_ERR(realfile))
+ return PTR_ERR(realfile);
- return ret;
+ return backing_file_splice_read(realfile, ppos, pipe, len, flags, &ctx);
}
/*
* Calling iter_file_splice_write() directly from overlay's f_op may deadlock
* due to lock order inversion between pipe->mutex in iter_file_splice_write()
- * and file_start_write(fd_file(real)) in ovl_write_iter().
+ * and file_start_write(realfile) in ovl_write_iter().
*
* So do everything ovl_write_iter() does and call iter_file_splice_write() on
* the real file.
@@ -434,7 +414,7 @@ static ssize_t ovl_splice_read(struct file *in, loff_t *ppos,
static ssize_t ovl_splice_write(struct pipe_inode_info *pipe, struct file *out,
loff_t *ppos, size_t len, unsigned int flags)
{
- struct fd real;
+ struct file *realfile;
struct inode *inode = file_inode(out);
ssize_t ret;
struct backing_file_ctx ctx = {
@@ -447,12 +427,12 @@ static ssize_t ovl_splice_write(struct pipe_inode_info *pipe, struct file *out,
/* Update mode */
ovl_copyattr(inode);
- ret = ovl_real_fdget(out, &real);
- if (ret)
+ realfile = ovl_real_file(out);
+ ret = PTR_ERR(realfile);
+ if (IS_ERR(realfile))
goto out_unlock;
- ret = backing_file_splice_write(pipe, fd_file(real), ppos, len, flags, &ctx);
- fdput(real);
+ ret = backing_file_splice_write(pipe, realfile, ppos, len, flags, &ctx);
out_unlock:
inode_unlock(inode);
@@ -497,7 +477,7 @@ static int ovl_mmap(struct file *file, struct vm_area_struct *vma)
static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
{
struct inode *inode = file_inode(file);
- struct fd real;
+ struct file *realfile;
const struct cred *old_cred;
int ret;
@@ -508,19 +488,18 @@ static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len
if (ret)
goto out_unlock;
- ret = ovl_real_fdget(file, &real);
- if (ret)
+ realfile = ovl_real_file(file);
+ ret = PTR_ERR(realfile);
+ if (IS_ERR(realfile))
goto out_unlock;
old_cred = ovl_override_creds(file_inode(file)->i_sb);
- ret = vfs_fallocate(fd_file(real), mode, offset, len);
+ ret = vfs_fallocate(realfile, mode, offset, len);
revert_creds(old_cred);
/* Update size */
ovl_file_modified(file);
- fdput(real);
-
out_unlock:
inode_unlock(inode);
@@ -529,20 +508,18 @@ static long ovl_fallocate(struct file *file, int mode, loff_t offset, loff_t len
static int ovl_fadvise(struct file *file, loff_t offset, loff_t len, int advice)
{
- struct fd real;
+ struct file *realfile;
const struct cred *old_cred;
int ret;
- ret = ovl_real_fdget(file, &real);
- if (ret)
- return ret;
+ realfile = ovl_real_file(file);
+ if (IS_ERR(realfile))
+ return PTR_ERR(realfile);
old_cred = ovl_override_creds(file_inode(file)->i_sb);
- ret = vfs_fadvise(fd_file(real), offset, len, advice);
+ ret = vfs_fadvise(realfile, offset, len, advice);
revert_creds(old_cred);
- fdput(real);
-
return ret;
}
@@ -557,7 +534,7 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,
loff_t len, unsigned int flags, enum ovl_copyop op)
{
struct inode *inode_out = file_inode(file_out);
- struct fd real_in, real_out;
+ struct file *realfile_in, *realfile_out;
const struct cred *old_cred;
loff_t ret;
@@ -570,31 +547,31 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,
goto out_unlock;
}
- ret = ovl_real_fdget(file_out, &real_out);
- if (ret)
+ realfile_out = ovl_real_file(file_out);
+ ret = PTR_ERR(realfile_out);
+ if (IS_ERR(realfile_out))
goto out_unlock;
- ret = ovl_real_fdget(file_in, &real_in);
- if (ret) {
- fdput(real_out);
+ realfile_in = ovl_real_file(file_in);
+ ret = PTR_ERR(realfile_in);
+ if (IS_ERR(realfile_in))
goto out_unlock;
- }
old_cred = ovl_override_creds(file_inode(file_out)->i_sb);
switch (op) {
case OVL_COPY:
- ret = vfs_copy_file_range(fd_file(real_in), pos_in,
- fd_file(real_out), pos_out, len, flags);
+ ret = vfs_copy_file_range(realfile_in, pos_in,
+ realfile_out, pos_out, len, flags);
break;
case OVL_CLONE:
- ret = vfs_clone_file_range(fd_file(real_in), pos_in,
- fd_file(real_out), pos_out, len, flags);
+ ret = vfs_clone_file_range(realfile_in, pos_in,
+ realfile_out, pos_out, len, flags);
break;
case OVL_DEDUPE:
- ret = vfs_dedupe_file_range_one(fd_file(real_in), pos_in,
- fd_file(real_out), pos_out, len,
+ ret = vfs_dedupe_file_range_one(realfile_in, pos_in,
+ realfile_out, pos_out, len,
flags);
break;
}
@@ -603,9 +580,6 @@ static loff_t ovl_copyfile(struct file *file_in, loff_t pos_in,
/* Update size */
ovl_file_modified(file_out);
- fdput(real_in);
- fdput(real_out);
-
out_unlock:
inode_unlock(inode_out);
@@ -649,20 +623,19 @@ static loff_t ovl_remap_file_range(struct file *file_in, loff_t pos_in,
static int ovl_flush(struct file *file, fl_owner_t id)
{
- struct fd real;
+ struct file *realfile;
const struct cred *old_cred;
- int err;
+ int err = 0;
- err = ovl_real_fdget(file, &real);
- if (err)
- return err;
+ realfile = ovl_real_file(file);
+ if (IS_ERR(realfile))
+ return PTR_ERR(realfile);
- if (fd_file(real)->f_op->flush) {
+ if (realfile->f_op->flush) {
old_cred = ovl_override_creds(file_inode(file)->i_sb);
- err = fd_file(real)->f_op->flush(fd_file(real), id);
+ err = realfile->f_op->flush(realfile, id);
revert_creds(old_cred);
}
- fdput(real);
return err;
}
--
2.34.1
