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yaml
---
r: 328971
b: refs/heads/master
c: 0ee8cdf
h: refs/heads/master
i:
  328969: be7abe4
  328967: cae26f0
v: v3
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Al Viro committed Sep 27, 2012
1 parent 8e1f9c8 commit dca4485
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Showing 3 changed files with 107 additions and 107 deletions.
2 changes: 1 addition & 1 deletion [refs]
Original file line number Diff line number Diff line change
@@ -1,2 +1,2 @@
---
refs/heads/master: f869e8a7f753e3fd43d6483e796774776f645edb
refs/heads/master: 0ee8cdfe6af052deb56dccd54838a1eb32fb4ca2
106 changes: 106 additions & 0 deletions trunk/fs/file.c
Original file line number Diff line number Diff line change
Expand Up @@ -625,3 +625,109 @@ void fd_install(unsigned int fd, struct file *file)
}

EXPORT_SYMBOL(fd_install);

struct file *fget(unsigned int fd)
{
struct file *file;
struct files_struct *files = current->files;

rcu_read_lock();
file = fcheck_files(files, fd);
if (file) {
/* File object ref couldn't be taken */
if (file->f_mode & FMODE_PATH ||
!atomic_long_inc_not_zero(&file->f_count))
file = NULL;
}
rcu_read_unlock();

return file;
}

EXPORT_SYMBOL(fget);

struct file *fget_raw(unsigned int fd)
{
struct file *file;
struct files_struct *files = current->files;

rcu_read_lock();
file = fcheck_files(files, fd);
if (file) {
/* File object ref couldn't be taken */
if (!atomic_long_inc_not_zero(&file->f_count))
file = NULL;
}
rcu_read_unlock();

return file;
}

EXPORT_SYMBOL(fget_raw);

/*
* Lightweight file lookup - no refcnt increment if fd table isn't shared.
*
* You can use this instead of fget if you satisfy all of the following
* conditions:
* 1) You must call fput_light before exiting the syscall and returning control
* to userspace (i.e. you cannot remember the returned struct file * after
* returning to userspace).
* 2) You must not call filp_close on the returned struct file * in between
* calls to fget_light and fput_light.
* 3) You must not clone the current task in between the calls to fget_light
* and fput_light.
*
* The fput_needed flag returned by fget_light should be passed to the
* corresponding fput_light.
*/
struct file *fget_light(unsigned int fd, int *fput_needed)
{
struct file *file;
struct files_struct *files = current->files;

*fput_needed = 0;
if (atomic_read(&files->count) == 1) {
file = fcheck_files(files, fd);
if (file && (file->f_mode & FMODE_PATH))
file = NULL;
} else {
rcu_read_lock();
file = fcheck_files(files, fd);
if (file) {
if (!(file->f_mode & FMODE_PATH) &&
atomic_long_inc_not_zero(&file->f_count))
*fput_needed = 1;
else
/* Didn't get the reference, someone's freed */
file = NULL;
}
rcu_read_unlock();
}

return file;
}

struct file *fget_raw_light(unsigned int fd, int *fput_needed)
{
struct file *file;
struct files_struct *files = current->files;

*fput_needed = 0;
if (atomic_read(&files->count) == 1) {
file = fcheck_files(files, fd);
} else {
rcu_read_lock();
file = fcheck_files(files, fd);
if (file) {
if (atomic_long_inc_not_zero(&file->f_count))
*fput_needed = 1;
else
/* Didn't get the reference, someone's freed */
file = NULL;
}
rcu_read_unlock();
}

return file;
}
106 changes: 0 additions & 106 deletions trunk/fs/file_table.c
Original file line number Diff line number Diff line change
Expand Up @@ -339,112 +339,6 @@ void __fput_sync(struct file *file)

EXPORT_SYMBOL(fput);

struct file *fget(unsigned int fd)
{
struct file *file;
struct files_struct *files = current->files;

rcu_read_lock();
file = fcheck_files(files, fd);
if (file) {
/* File object ref couldn't be taken */
if (file->f_mode & FMODE_PATH ||
!atomic_long_inc_not_zero(&file->f_count))
file = NULL;
}
rcu_read_unlock();

return file;
}

EXPORT_SYMBOL(fget);

struct file *fget_raw(unsigned int fd)
{
struct file *file;
struct files_struct *files = current->files;

rcu_read_lock();
file = fcheck_files(files, fd);
if (file) {
/* File object ref couldn't be taken */
if (!atomic_long_inc_not_zero(&file->f_count))
file = NULL;
}
rcu_read_unlock();

return file;
}

EXPORT_SYMBOL(fget_raw);

/*
* Lightweight file lookup - no refcnt increment if fd table isn't shared.
*
* You can use this instead of fget if you satisfy all of the following
* conditions:
* 1) You must call fput_light before exiting the syscall and returning control
* to userspace (i.e. you cannot remember the returned struct file * after
* returning to userspace).
* 2) You must not call filp_close on the returned struct file * in between
* calls to fget_light and fput_light.
* 3) You must not clone the current task in between the calls to fget_light
* and fput_light.
*
* The fput_needed flag returned by fget_light should be passed to the
* corresponding fput_light.
*/
struct file *fget_light(unsigned int fd, int *fput_needed)
{
struct file *file;
struct files_struct *files = current->files;

*fput_needed = 0;
if (atomic_read(&files->count) == 1) {
file = fcheck_files(files, fd);
if (file && (file->f_mode & FMODE_PATH))
file = NULL;
} else {
rcu_read_lock();
file = fcheck_files(files, fd);
if (file) {
if (!(file->f_mode & FMODE_PATH) &&
atomic_long_inc_not_zero(&file->f_count))
*fput_needed = 1;
else
/* Didn't get the reference, someone's freed */
file = NULL;
}
rcu_read_unlock();
}

return file;
}

struct file *fget_raw_light(unsigned int fd, int *fput_needed)
{
struct file *file;
struct files_struct *files = current->files;

*fput_needed = 0;
if (atomic_read(&files->count) == 1) {
file = fcheck_files(files, fd);
} else {
rcu_read_lock();
file = fcheck_files(files, fd);
if (file) {
if (atomic_long_inc_not_zero(&file->f_count))
*fput_needed = 1;
else
/* Didn't get the reference, someone's freed */
file = NULL;
}
rcu_read_unlock();
}

return file;
}

void put_filp(struct file *file)
{
if (atomic_long_dec_and_test(&file->f_count)) {
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