Commit c5b1f0d9 authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

locks/nfsd: allocate file lock outside of spinlock 



As suggested by Christoph Hellwig, this moves allocation
of new file locks out of generic_setlease into the
callers, nfs4_open_delegation and fcntl_setlease in order
to allow GFP_KERNEL allocations when lock_flocks has
become a spinlock.

Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Acked-by: default avatarJ. Bruce Fields <bfields@redhat.com>
parent a282a1fa

fs/locks.c

+12 −24
Original line number Diff line number Diff line
@@ -162,10 +162,11 @@ EXPORT_SYMBOL_GPL(unlock_flocks); 
static struct kmem_cache *filelock_cache __read_mostly;



/* Allocate an empty lock structure. */

static struct file_lock *locks_alloc_lock(void)

struct file_lock *locks_alloc_lock(void)

{

	return kmem_cache_alloc(filelock_cache, GFP_KERNEL);

}

EXPORT_SYMBOL_GPL(locks_alloc_lock);



void locks_release_private(struct file_lock *fl)

{
@@ -1365,7 +1366,6 @@ int fcntl_getlease(struct file *filp) 
int generic_setlease(struct file *filp, long arg, struct file_lock **flp)

{

	struct file_lock *fl, **before, **my_before = NULL, *lease;

	struct file_lock *new_fl = NULL;

	struct dentry *dentry = filp->f_path.dentry;

	struct inode *inode = dentry->d_inode;

	int error, rdlease_count = 0, wrlease_count = 0;
@@ -1385,11 +1385,6 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp) 
	lease = *flp;



	if (arg != F_UNLCK) {

		error = -ENOMEM;

		new_fl = locks_alloc_lock();

		if (new_fl == NULL)

			goto out;



		error = -EAGAIN;

		if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))

			goto out;
@@ -1434,7 +1429,6 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp) 
		goto out;

	}



	error = 0;

	if (arg == F_UNLCK)

		goto out;
@@ -1442,15 +1436,11 @@ int generic_setlease(struct file *filp, long arg, struct file_lock **flp) 
	if (!leases_enable)

		goto out;



	locks_copy_lock(new_fl, lease);

	locks_insert_lock(before, new_fl);



	*flp = new_fl;

	locks_insert_lock(before, lease);

	return 0;



out:

	if (new_fl != NULL)

		locks_free_lock(new_fl);

	locks_free_lock(lease);

	return error;

}

EXPORT_SYMBOL(generic_setlease);
@@ -1514,26 +1504,24 @@ EXPORT_SYMBOL_GPL(vfs_setlease); 
 */

int fcntl_setlease(unsigned int fd, struct file *filp, long arg)

{

	struct file_lock fl, *flp = &fl;

	struct file_lock *fl;

	struct inode *inode = filp->f_path.dentry->d_inode;

	int error;



	locks_init_lock(&fl);

	error = lease_init(filp, arg, &fl);

	if (error)

		return error;

	fl = lease_alloc(filp, arg);

	if (IS_ERR(fl))

		return PTR_ERR(fl);



	lock_flocks();



	error = __vfs_setlease(filp, arg, &flp);

	error = __vfs_setlease(filp, arg, &fl);

	if (error || arg == F_UNLCK)

		goto out_unlock;



	error = fasync_helper(fd, filp, 1, &flp->fl_fasync);

	error = fasync_helper(fd, filp, 1, &fl->fl_fasync);

	if (error < 0) {

		/* remove lease just inserted by setlease */

		flp->fl_type = F_UNLCK | F_INPROGRESS;

		flp->fl_break_time = jiffies - 10;

		fl->fl_type = F_UNLCK | F_INPROGRESS;

		fl->fl_break_time = jiffies - 10;

		time_out_leases(inode);

		goto out_unlock;

	}

fs/nfsd/nfs4state.c

+15 −11
Original line number Diff line number Diff line
@@ -2614,7 +2614,7 @@ nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open, struct nfs4_sta 
	struct nfs4_delegation *dp;

	struct nfs4_stateowner *sop = stp->st_stateowner;

	int cb_up = atomic_read(&sop->so_client->cl_cb_set);

	struct file_lock fl, *flp = &fl;

	struct file_lock *fl;

	int status, flag = 0;



	flag = NFS4_OPEN_DELEGATE_NONE;
@@ -2648,20 +2648,24 @@ nfs4_open_delegation(struct svc_fh *fh, struct nfsd4_open *open, struct nfs4_sta 
		flag = NFS4_OPEN_DELEGATE_NONE;

		goto out;

	}

	locks_init_lock(&fl);

	fl.fl_lmops = &nfsd_lease_mng_ops;

	fl.fl_flags = FL_LEASE;

	fl.fl_type = flag == NFS4_OPEN_DELEGATE_READ? F_RDLCK: F_WRLCK;

	fl.fl_end = OFFSET_MAX;

	fl.fl_owner =  (fl_owner_t)dp;

	fl.fl_file = find_readable_file(stp->st_file);

	BUG_ON(!fl.fl_file);

	fl.fl_pid = current->tgid;

	status = -ENOMEM;

	fl = locks_alloc_lock();

	if (!fl)

		goto out;

	locks_init_lock(fl);

	fl->fl_lmops = &nfsd_lease_mng_ops;

	fl->fl_flags = FL_LEASE;

	fl->fl_type = flag == NFS4_OPEN_DELEGATE_READ? F_RDLCK: F_WRLCK;

	fl->fl_end = OFFSET_MAX;

	fl->fl_owner =  (fl_owner_t)dp;

	fl->fl_file = find_readable_file(stp->st_file);

	BUG_ON(!fl->fl_file);

	fl->fl_pid = current->tgid;



	/* vfs_setlease checks to see if delegation should be handed out.

	 * the lock_manager callbacks fl_mylease and fl_change are used

	 */

	if ((status = vfs_setlease(fl.fl_file, fl.fl_type, &flp))) {

	if ((status = vfs_setlease(fl->fl_file, fl->fl_type, &fl))) {

		dprintk("NFSD: setlease failed [%d], no delegation\n", status);

		unhash_delegation(dp);

		flag = NFS4_OPEN_DELEGATE_NONE;

include/linux/fs.h

+1 −0
Original line number Diff line number Diff line
@@ -1113,6 +1113,7 @@ extern int fcntl_getlease(struct file *filp); 


/* fs/locks.c */

extern void locks_init_lock(struct file_lock *);

extern struct file_lock * locks_alloc_lock(void);

extern void locks_copy_lock(struct file_lock *, struct file_lock *);

extern void __locks_copy_lock(struct file_lock *, const struct file_lock *);

extern void locks_remove_posix(struct file *, fl_owner_t);

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