summaryrefslogtreecommitdiffstats
path: root/fs
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-03-26 16:14:02 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-03-26 16:14:02 -0700
commit8e9d2089723d08d51e66c5eea49253d76e27941e (patch)
treecf15609d5eeb0c1f3a39231d8ce793d3c8ad0ed0 /fs
parentba1eb95cf3cc666769afe42eaa15a3a34ae82f94 (diff)
parent60aa49243d09afc873f082567d2e3c16634ced84 (diff)
Merge branch 'bkl-removal' of git://git.lwn.net/linux-2.6
* 'bkl-removal' of git://git.lwn.net/linux-2.6: Rationalize fasync return values Move FASYNC bit handling to f_op->fasync() Use f_lock to protect f_flags Rename struct file->f_ep_lock
Diffstat (limited to 'fs')
-rw-r--r--fs/eventpoll.c12
-rw-r--r--fs/fcntl.c33
-rw-r--r--fs/file_table.c1
-rw-r--r--fs/ioctl.c18
-rw-r--r--fs/nfsd/vfs.c5
-rw-r--r--fs/pipe.c16
6 files changed, 39 insertions, 46 deletions
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 011b9b8c90c..c5c424f23fd 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -417,10 +417,10 @@ static int ep_remove(struct eventpoll *ep, struct epitem *epi)
ep_unregister_pollwait(ep, epi);
/* Remove the current item from the list of epoll hooks */
- spin_lock(&file->f_ep_lock);
+ spin_lock(&file->f_lock);
if (ep_is_linked(&epi->fllink))
list_del_init(&epi->fllink);
- spin_unlock(&file->f_ep_lock);
+ spin_unlock(&file->f_lock);
rb_erase(&epi->rbn, &ep->rbr);
@@ -538,7 +538,7 @@ void eventpoll_release_file(struct file *file)
struct epitem *epi;
/*
- * We don't want to get "file->f_ep_lock" because it is not
+ * We don't want to get "file->f_lock" because it is not
* necessary. It is not necessary because we're in the "struct file"
* cleanup path, and this means that noone is using this file anymore.
* So, for example, epoll_ctl() cannot hit here sicne if we reach this
@@ -547,6 +547,8 @@ void eventpoll_release_file(struct file *file)
* will correctly serialize the operation. We do need to acquire
* "ep->mtx" after "epmutex" because ep_remove() requires it when called
* from anywhere but ep_free().
+ *
+ * Besides, ep_remove() acquires the lock, so we can't hold it here.
*/
mutex_lock(&epmutex);
@@ -785,9 +787,9 @@ static int ep_insert(struct eventpoll *ep, struct epoll_event *event,
goto error_unregister;
/* Add the current item to the list of active epoll hook for this file */
- spin_lock(&tfile->f_ep_lock);
+ spin_lock(&tfile->f_lock);
list_add_tail(&epi->fllink, &tfile->f_ep_links);
- spin_unlock(&tfile->f_ep_lock);
+ spin_unlock(&tfile->f_lock);
/*
* Add the current item to the RB tree. All RB tree operations are
diff --git a/fs/fcntl.c b/fs/fcntl.c
index bd215cc791d..d865ca66ccb 100644
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -141,7 +141,7 @@ SYSCALL_DEFINE1(dup, unsigned int, fildes)
return ret;
}
-#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | FASYNC | O_DIRECT | O_NOATIME)
+#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT | O_NOATIME)
static int setfl(int fd, struct file * filp, unsigned long arg)
{
@@ -177,21 +177,21 @@ static int setfl(int fd, struct file * filp, unsigned long arg)
return error;
/*
- * We still need a lock here for now to keep multiple FASYNC calls
- * from racing with each other.
+ * ->fasync() is responsible for setting the FASYNC bit.
*/
- lock_kernel();
- if ((arg ^ filp->f_flags) & FASYNC) {
- if (filp->f_op && filp->f_op->fasync) {
- error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
- if (error < 0)
- goto out;
- }
+ if (((arg ^ filp->f_flags) & FASYNC) && filp->f_op &&
+ filp->f_op->fasync) {
+ error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
+ if (error < 0)
+ goto out;
+ if (error > 0)
+ error = 0;
}
-
+ spin_lock(&filp->f_lock);
filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK);
+ spin_unlock(&filp->f_lock);
+
out:
- unlock_kernel();
return error;
}
@@ -516,7 +516,7 @@ static DEFINE_RWLOCK(fasync_lock);
static struct kmem_cache *fasync_cache __read_mostly;
/*
- * fasync_helper() is used by some character device drivers (mainly mice)
+ * fasync_helper() is used by almost all character device drivers
* to set up the fasync queue. It returns negative on error, 0 if it did
* no changes and positive if it added/deleted the entry.
*/
@@ -555,6 +555,13 @@ int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fap
result = 1;
}
out:
+ /* Fix up FASYNC bit while still holding fasync_lock */
+ spin_lock(&filp->f_lock);
+ if (on)
+ filp->f_flags |= FASYNC;
+ else
+ filp->f_flags &= ~FASYNC;
+ spin_unlock(&filp->f_lock);
write_unlock_irq(&fasync_lock);
return result;
}
diff --git a/fs/file_table.c b/fs/file_table.c
index da806aceae3..b74a8e1da91 100644
--- a/fs/file_table.c
+++ b/fs/file_table.c
@@ -128,6 +128,7 @@ struct file *get_empty_filp(void)
atomic_long_set(&f->f_count, 1);
rwlock_init(&f->f_owner.lock);
f->f_cred = get_cred(cred);
+ spin_lock_init(&f->f_lock);
eventpoll_init_file(f);
/* f->f_version: 0 */
return f;
diff --git a/fs/ioctl.c b/fs/ioctl.c
index 240ec63984c..ac2d47e4392 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -404,10 +404,12 @@ static int ioctl_fionbio(struct file *filp, int __user *argp)
if (O_NONBLOCK != O_NDELAY)
flag |= O_NDELAY;
#endif
+ spin_lock(&filp->f_lock);
if (on)
filp->f_flags |= flag;
else
filp->f_flags &= ~flag;
+ spin_unlock(&filp->f_lock);
return error;
}
@@ -425,18 +427,12 @@ static int ioctl_fioasync(unsigned int fd, struct file *filp,
/* Did FASYNC state change ? */
if ((flag ^ filp->f_flags) & FASYNC) {
if (filp->f_op && filp->f_op->fasync)
+ /* fasync() adjusts filp->f_flags */
error = filp->f_op->fasync(fd, filp, on);
else
error = -ENOTTY;
}
- if (error)
- return error;
-
- if (on)
- filp->f_flags |= FASYNC;
- else
- filp->f_flags &= ~FASYNC;
- return error;
+ return error < 0 ? error : 0;
}
static int ioctl_fsfreeze(struct file *filp)
@@ -499,17 +495,11 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
break;
case FIONBIO:
- /* BKL needed to avoid races tweaking f_flags */
- lock_kernel();
error = ioctl_fionbio(filp, argp);
- unlock_kernel();
break;
case FIOASYNC:
- /* BKL needed to avoid races tweaking f_flags */
- lock_kernel();
error = ioctl_fioasync(fd, filp, argp);
- unlock_kernel();
break;
case FIOQSIZE:
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 6e50aaa56ca..c165a6403df 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -998,8 +998,11 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
if (!EX_ISSYNC(exp))
stable = 0;
- if (stable && !EX_WGATHER(exp))
+ if (stable && !EX_WGATHER(exp)) {
+ spin_lock(&file->f_lock);
file->f_flags |= O_SYNC;
+ spin_unlock(&file->f_lock);
+ }
/* Write the data. */
oldfs = get_fs(); set_fs(KERNEL_DS);
diff --git a/fs/pipe.c b/fs/pipe.c
index 14f502b89cf..94ad15967cf 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -667,10 +667,7 @@ pipe_read_fasync(int fd, struct file *filp, int on)
retval = fasync_helper(fd, filp, on, &inode->i_pipe->fasync_readers);
mutex_unlock(&inode->i_mutex);
- if (retval < 0)
- return retval;
-
- return 0;
+ return retval;
}
@@ -684,10 +681,7 @@ pipe_write_fasync(int fd, struct file *filp, int on)
retval = fasync_helper(fd, filp, on, &inode->i_pipe->fasync_writers);
mutex_unlock(&inode->i_mutex);
- if (retval < 0)
- return retval;
-
- return 0;
+ return retval;
}
@@ -706,11 +700,7 @@ pipe_rdwr_fasync(int fd, struct file *filp, int on)
fasync_helper(-1, filp, 0, &pipe->fasync_readers);
}
mutex_unlock(&inode->i_mutex);
-
- if (retval < 0)
- return retval;
-
- return 0;
+ return retval;
}