From: Sukadev Bhattiprolu <[email protected]> Extract core functionality of fcntl_setlk() and fcntl_setlk64() into separate functions, flock_set() and flock64_set() respective. These functions can be also used when restarting a checkpointed application and restoring its file-locks.
Signed-off-by: Sukadev Bhattiprolu <[email protected]> Acked-by: Oren Laadan <[email protected]> --- fs/locks.c | 76 +++++++++++++++++++++++++++++++-------------------- include/linux/fs.h | 4 +++ 2 files changed, 50 insertions(+), 30 deletions(-) diff --git a/fs/locks.c b/fs/locks.c index e30ad46..c3fc56d 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -1807,14 +1807,13 @@ static int do_lock_file_wait(struct file *filp, unsigned int cmd, return error; } -/* Apply the lock described by l to an open file descriptor. +/* Apply the lock described by @flock to an open file descriptor. * This implements both the F_SETLK and F_SETLKW commands of fcntl(). */ -int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, - struct flock __user *l) +int do_fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, + struct flock *flock) { struct file_lock *file_lock = locks_alloc_lock(); - struct flock flock; struct inode *inode; struct file *f; int error; @@ -1822,13 +1821,6 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, if (file_lock == NULL) return -ENOLCK; - /* - * This might block, so we do it before checking the inode. - */ - error = -EFAULT; - if (copy_from_user(&flock, l, sizeof(flock))) - goto out; - inode = filp->f_path.dentry->d_inode; /* Don't allow mandatory locks on files that may be memory mapped @@ -1840,7 +1832,7 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, } again: - error = flock_to_posix_lock(filp, file_lock, &flock); + error = flock_to_posix_lock(filp, file_lock, flock); if (error) goto out; if (cmd == F_SETLKW) { @@ -1848,7 +1840,7 @@ again: } error = -EBADF; - switch (flock.l_type) { + switch (flock->l_type) { case F_RDLCK: if (!(filp->f_mode & FMODE_READ)) goto out; @@ -1878,8 +1870,8 @@ again: spin_lock(¤t->files->file_lock); f = fcheck(fd); spin_unlock(¤t->files->file_lock); - if (!error && f != filp && flock.l_type != F_UNLCK) { - flock.l_type = F_UNLCK; + if (!error && f != filp && flock->l_type != F_UNLCK) { + flock->l_type = F_UNLCK; goto again; } @@ -1888,6 +1880,23 @@ out: return error; } +int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd, + struct flock __user *l) +{ + int error; + struct flock flock; + + /* + * This might block, so we do it before checking the inode + * in flock_set(). + */ + error = -EFAULT; + if (copy_from_user(&flock, l, sizeof(flock))) + return error; + + return do_fcntl_setlk(fd, filp, cmd, &flock); +} + #if BITS_PER_LONG == 32 /* Report the first existing lock that would conflict with l. * This implements the F_GETLK command of fcntl(). @@ -1925,14 +1934,13 @@ out: return error; } -/* Apply the lock described by l to an open file descriptor. +/* Apply the lock described by @flock to an open file descriptor. * This implements both the F_SETLK and F_SETLKW commands of fcntl(). */ -int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd, - struct flock64 __user *l) +int do_fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd, + struct flock64 *flock) { struct file_lock *file_lock = locks_alloc_lock(); - struct flock64 flock; struct inode *inode; struct file *f; int error; @@ -1940,13 +1948,6 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd, if (file_lock == NULL) return -ENOLCK; - /* - * This might block, so we do it before checking the inode. - */ - error = -EFAULT; - if (copy_from_user(&flock, l, sizeof(flock))) - goto out; - inode = filp->f_path.dentry->d_inode; /* Don't allow mandatory locks on files that may be memory mapped @@ -1958,7 +1959,7 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd, } again: - error = flock64_to_posix_lock(filp, file_lock, &flock); + error = flock64_to_posix_lock(filp, file_lock, flock); if (error) goto out; if (cmd == F_SETLKW64) { @@ -1966,7 +1967,7 @@ again: } error = -EBADF; - switch (flock.l_type) { + switch (flock->l_type) { case F_RDLCK: if (!(filp->f_mode & FMODE_READ)) goto out; @@ -1991,8 +1992,8 @@ again: spin_lock(¤t->files->file_lock); f = fcheck(fd); spin_unlock(¤t->files->file_lock); - if (!error && f != filp && flock.l_type != F_UNLCK) { - flock.l_type = F_UNLCK; + if (!error && f != filp && flock->l_type != F_UNLCK) { + flock->l_type = F_UNLCK; goto again; } @@ -2002,6 +2003,21 @@ out: } #endif /* BITS_PER_LONG == 32 */ +int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd, + struct flock64 __user *l) +{ + struct flock64 flock; + + /* + * This might block, so we do it before checking the inode in + * flock64_set(). + */ + if (copy_from_user(&flock, l, sizeof(flock))) + return -EFAULT; + + return do_fcntl_setlk64(fd, filp, cmd, &flock); +} + /* * This function is called when the file is being removed * from the task's fd array. POSIX locks belonging to this task diff --git a/include/linux/fs.h b/include/linux/fs.h index 3d8bf75..7f38be1 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1121,11 +1121,15 @@ extern void send_sigio(struct fown_struct *fown, int fd, int band); extern int fcntl_getlk(struct file *, struct flock __user *); extern int fcntl_setlk(unsigned int, struct file *, unsigned int, struct flock __user *); +extern int do_fcntl_setlk(unsigned int, struct file *, unsigned int, + struct flock *); #if BITS_PER_LONG == 32 extern int fcntl_getlk64(struct file *, struct flock64 __user *); extern int fcntl_setlk64(unsigned int, struct file *, unsigned int, struct flock64 __user *); +extern int do_fcntl_set(unsigned int, struct file *, unsigned int, + struct flock64 *); #endif extern int fcntl_setlease(unsigned int fd, struct file *filp, long arg); -- 1.7.1 _______________________________________________ Containers mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
