Commit 7420a8c0 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'flock' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl 

* 'flock' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
  locks: turn lock_flocks into a spinlock
  fasync: re-organize fasync entry insertion to allow it under a spinlock
  locks/nfsd: allocate file lock outside of spinlock
  lockd: fix nlmsvc_notify_blocked locking
  lockd: push lock_flocks down
parents 12ba8d1e 72f98e72

fs/Kconfig

+0 −1
Original line number Diff line number Diff line
@@ -53,7 +53,6 @@ config EXPORTFS 
config FILE_LOCKING

	bool "Enable POSIX file locking API" if EMBEDDED

	default y

	select BKL # while lockd still uses it.

	help

	  This option enables standard file locking support, required

          for filesystems like NFS and for the flock() system

fs/fcntl.c

+50 −16
Original line number Diff line number Diff line
@@ -640,7 +640,7 @@ static void fasync_free_rcu(struct rcu_head *head) 
 * match the state "is the filp on a fasync list".

 *

 */

static int fasync_remove_entry(struct file *filp, struct fasync_struct **fapp)

int fasync_remove_entry(struct file *filp, struct fasync_struct **fapp)

{

	struct fasync_struct *fa, **fp;

	int result = 0;
@@ -666,21 +666,28 @@ static int fasync_remove_entry(struct file *filp, struct fasync_struct **fapp) 
	return result;

}



struct fasync_struct *fasync_alloc(void)

{

	return kmem_cache_alloc(fasync_cache, GFP_KERNEL);

}



/*

 * Add a fasync entry. Return negative on error, positive if

 * added, and zero if did nothing but change an existing one.

 *

 * NOTE! It is very important that the FASYNC flag always

 * match the state "is the filp on a fasync list".

 * NOTE! This can be used only for unused fasync entries:

 * entries that actually got inserted on the fasync list

 * need to be released by rcu - see fasync_remove_entry.

 */

static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fapp)

void fasync_free(struct fasync_struct *new)

{

	struct fasync_struct *new, *fa, **fp;

	int result = 0;

	kmem_cache_free(fasync_cache, new);

}



	new = kmem_cache_alloc(fasync_cache, GFP_KERNEL);

	if (!new)

		return -ENOMEM;

/*

 * Insert a new entry into the fasync list.  Return the pointer to the

 * old one if we didn't use the new one.

 */

struct fasync_struct *fasync_insert_entry(int fd, struct file *filp, struct fasync_struct **fapp, struct fasync_struct *new)

{

        struct fasync_struct *fa, **fp;



	spin_lock(&filp->f_lock);

	spin_lock(&fasync_lock);
@@ -691,8 +698,6 @@ static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fa 
		spin_lock_irq(&fa->fa_lock);

		fa->fa_fd = fd;

		spin_unlock_irq(&fa->fa_lock);



		kmem_cache_free(fasync_cache, new);

		goto out;

	}
@@ -702,13 +707,42 @@ static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fa 
	new->fa_fd = fd;

	new->fa_next = *fapp;

	rcu_assign_pointer(*fapp, new);

	result = 1;

	filp->f_flags |= FASYNC;



out:

	spin_unlock(&fasync_lock);

	spin_unlock(&filp->f_lock);

	return result;

	return fa;

}



/*

 * Add a fasync entry. Return negative on error, positive if

 * added, and zero if did nothing but change an existing one.

 *

 * NOTE! It is very important that the FASYNC flag always

 * match the state "is the filp on a fasync list".

 */

static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fapp)

{

	struct fasync_struct *new;



	new = fasync_alloc();

	if (!new)

		return -ENOMEM;



	/*

	 * fasync_insert_entry() returns the old (update) entry if

	 * it existed.

	 *

	 * So free the (unused) new entry and return 0 to let the

	 * caller know that we didn't add any new fasync entries.

	 */

	if (fasync_insert_entry(fd, filp, fapp, new)) {

		fasync_free(new);

		return 0;

	}



	return 1;

}



/*

fs/lockd/svc.c

+0 −11
Original line number Diff line number Diff line
@@ -22,7 +22,6 @@ 
#include <linux/in.h>

#include <linux/uio.h>

#include <linux/smp.h>

#include <linux/smp_lock.h>

#include <linux/mutex.h>

#include <linux/kthread.h>

#include <linux/freezer.h>
@@ -130,15 +129,6 @@ lockd(void *vrqstp) 


	dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");



	/*

	 * FIXME: it would be nice if lockd didn't spend its entire life

	 * running under the BKL. At the very least, it would be good to

	 * have someone clarify what it's intended to protect here. I've

	 * seen some handwavy posts about posix locking needing to be

	 * done under the BKL, but it's far from clear.

	 */

	lock_kernel();



	if (!nlm_timeout)

		nlm_timeout = LOCKD_DFLT_TIMEO;

	nlmsvc_timeout = nlm_timeout * HZ;
@@ -195,7 +185,6 @@ lockd(void *vrqstp) 
	if (nlmsvc_ops)

		nlmsvc_invalidate_all();

	nlm_shutdown_hosts();

	unlock_kernel();

	return 0;

}

fs/lockd/svclock.c

+4 −2
Original line number Diff line number Diff line
@@ -700,14 +700,16 @@ nlmsvc_notify_blocked(struct file_lock *fl) 
	struct nlm_block	*block;



	dprintk("lockd: VFS unblock notification for block %p\n", fl);

	spin_lock(&nlm_blocked_lock);

	list_for_each_entry(block, &nlm_blocked, b_list) {

		if (nlm_compare_locks(&block->b_call->a_args.lock.fl, fl)) {

			nlmsvc_insert_block(block, 0);

			nlmsvc_insert_block_locked(block, 0);

			spin_unlock(&nlm_blocked_lock);

			svc_wake_up(block->b_daemon);

			return;

		}

	}



	spin_unlock(&nlm_blocked_lock);

	printk(KERN_WARNING "lockd: notification for unknown block!\n");

}

fs/lockd/svcsubs.c

+8 −1
Original line number Diff line number Diff line
@@ -170,6 +170,7 @@ nlm_traverse_locks(struct nlm_host *host, struct nlm_file *file, 


again:

	file->f_locks = 0;

	lock_flocks(); /* protects i_flock list */

	for (fl = inode->i_flock; fl; fl = fl->fl_next) {

		if (fl->fl_lmops != &nlmsvc_lock_operations)

			continue;
@@ -181,6 +182,7 @@ again: 
		if (match(lockhost, host)) {

			struct file_lock lock = *fl;



			unlock_flocks();

			lock.fl_type  = F_UNLCK;

			lock.fl_start = 0;

			lock.fl_end   = OFFSET_MAX;
@@ -192,6 +194,7 @@ again: 
			goto again;

		}

	}

	unlock_flocks();



	return 0;

}
@@ -226,10 +229,14 @@ nlm_file_inuse(struct nlm_file *file) 
	if (file->f_count || !list_empty(&file->f_blocks) || file->f_shares)

		return 1;



	lock_flocks();

	for (fl = inode->i_flock; fl; fl = fl->fl_next) {

		if (fl->fl_lmops == &nlmsvc_lock_operations)

		if (fl->fl_lmops == &nlmsvc_lock_operations) {

			unlock_flocks();

			return 1;

		}

	}

	unlock_flocks();

	file->f_locks = 0;

	return 0;

}

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