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knfsd: don't allocate file_locks on the stack
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struct file_lock is pretty large and really ought not live on the stack.
On my x86_64 machine, they're almost 200 bytes each.

    (gdb) p sizeof(struct file_lock)
    $1 = 192

...allocate them dynamically instead.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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@jtlayton
jtlayton authored and J. Bruce Fields committed Aug 21, 2012
1 parent 5592a3f commit 21179d8
Showing 1 changed file with 76 additions and 42 deletions.
118 changes: 76 additions & 42 deletions fs/nfsd/nfs4state.c
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Original file line number Diff line number Diff line change
Expand Up @@ -4046,8 +4046,8 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
struct nfs4_lockowner *lock_sop = NULL;
struct nfs4_ol_stateid *lock_stp;
struct file *filp = NULL;
struct file_lock file_lock;
struct file_lock conflock;
struct file_lock *file_lock = NULL;
struct file_lock *conflock = NULL;
__be32 status = 0;
bool new_state = false;
int lkflg;
Expand Down Expand Up @@ -4117,21 +4117,28 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
if (!locks_in_grace(SVC_NET(rqstp)) && lock->lk_reclaim)
goto out;

locks_init_lock(&file_lock);
file_lock = locks_alloc_lock();
if (!file_lock) {
dprintk("NFSD: %s: unable to allocate lock!\n", __func__);
status = nfserr_jukebox;
goto out;
}

locks_init_lock(file_lock);
switch (lock->lk_type) {
case NFS4_READ_LT:
case NFS4_READW_LT:
filp = find_readable_file(lock_stp->st_file);
if (filp)
get_lock_access(lock_stp, NFS4_SHARE_ACCESS_READ);
file_lock.fl_type = F_RDLCK;
file_lock->fl_type = F_RDLCK;
break;
case NFS4_WRITE_LT:
case NFS4_WRITEW_LT:
filp = find_writeable_file(lock_stp->st_file);
if (filp)
get_lock_access(lock_stp, NFS4_SHARE_ACCESS_WRITE);
file_lock.fl_type = F_WRLCK;
file_lock->fl_type = F_WRLCK;
break;
default:
status = nfserr_inval;
Expand All @@ -4141,17 +4148,23 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
status = nfserr_openmode;
goto out;
}
file_lock.fl_owner = (fl_owner_t)lock_sop;
file_lock.fl_pid = current->tgid;
file_lock.fl_file = filp;
file_lock.fl_flags = FL_POSIX;
file_lock.fl_lmops = &nfsd_posix_mng_ops;

file_lock.fl_start = lock->lk_offset;
file_lock.fl_end = last_byte_offset(lock->lk_offset, lock->lk_length);
nfs4_transform_lock_offset(&file_lock);
file_lock->fl_owner = (fl_owner_t)lock_sop;
file_lock->fl_pid = current->tgid;
file_lock->fl_file = filp;
file_lock->fl_flags = FL_POSIX;
file_lock->fl_lmops = &nfsd_posix_mng_ops;
file_lock->fl_start = lock->lk_offset;
file_lock->fl_end = last_byte_offset(lock->lk_offset, lock->lk_length);
nfs4_transform_lock_offset(file_lock);

conflock = locks_alloc_lock();
if (!conflock) {
dprintk("NFSD: %s: unable to allocate lock!\n", __func__);
status = nfserr_jukebox;
goto out;
}

err = vfs_lock_file(filp, F_SETLK, &file_lock, &conflock);
err = vfs_lock_file(filp, F_SETLK, file_lock, conflock);
switch (-err) {
case 0: /* success! */
update_stateid(&lock_stp->st_stid.sc_stateid);
Expand All @@ -4162,7 +4175,7 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
case (EAGAIN): /* conflock holds conflicting lock */
status = nfserr_denied;
dprintk("NFSD: nfsd4_lock: conflicting lock found!\n");
nfs4_set_lock_denied(&conflock, &lock->lk_denied);
nfs4_set_lock_denied(conflock, &lock->lk_denied);
break;
case (EDEADLK):
status = nfserr_deadlock;
Expand All @@ -4177,6 +4190,10 @@ nfsd4_lock(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
release_lockowner(lock_sop);
if (!cstate->replay_owner)
nfs4_unlock_state();
if (file_lock)
locks_free_lock(file_lock);
if (conflock)
locks_free_lock(conflock);
return status;
}

Expand Down Expand Up @@ -4205,7 +4222,7 @@ nfsd4_lockt(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
struct nfsd4_lockt *lockt)
{
struct inode *inode;
struct file_lock file_lock;
struct file_lock *file_lock = NULL;
struct nfs4_lockowner *lo;
__be32 status;
struct nfsd_net *nn = net_generic(&init_net, nfsd_net_id);
Expand All @@ -4226,15 +4243,21 @@ nfsd4_lockt(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
goto out;

inode = cstate->current_fh.fh_dentry->d_inode;
locks_init_lock(&file_lock);
file_lock = locks_alloc_lock();
if (!file_lock) {
dprintk("NFSD: %s: unable to allocate lock!\n", __func__);
status = nfserr_jukebox;
goto out;
}
locks_init_lock(file_lock);
switch (lockt->lt_type) {
case NFS4_READ_LT:
case NFS4_READW_LT:
file_lock.fl_type = F_RDLCK;
file_lock->fl_type = F_RDLCK;
break;
case NFS4_WRITE_LT:
case NFS4_WRITEW_LT:
file_lock.fl_type = F_WRLCK;
file_lock->fl_type = F_WRLCK;
break;
default:
dprintk("NFSD: nfs4_lockt: bad lock type!\n");
Expand All @@ -4244,25 +4267,27 @@ nfsd4_lockt(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,

lo = find_lockowner_str(inode, &lockt->lt_clientid, &lockt->lt_owner);
if (lo)
file_lock.fl_owner = (fl_owner_t)lo;
file_lock.fl_pid = current->tgid;
file_lock.fl_flags = FL_POSIX;
file_lock->fl_owner = (fl_owner_t)lo;
file_lock->fl_pid = current->tgid;
file_lock->fl_flags = FL_POSIX;

file_lock.fl_start = lockt->lt_offset;
file_lock.fl_end = last_byte_offset(lockt->lt_offset, lockt->lt_length);
file_lock->fl_start = lockt->lt_offset;
file_lock->fl_end = last_byte_offset(lockt->lt_offset, lockt->lt_length);

nfs4_transform_lock_offset(&file_lock);
nfs4_transform_lock_offset(file_lock);

status = nfsd_test_lock(rqstp, &cstate->current_fh, &file_lock);
status = nfsd_test_lock(rqstp, &cstate->current_fh, file_lock);
if (status)
goto out;

if (file_lock.fl_type != F_UNLCK) {
if (file_lock->fl_type != F_UNLCK) {
status = nfserr_denied;
nfs4_set_lock_denied(&file_lock, &lockt->lt_denied);
nfs4_set_lock_denied(file_lock, &lockt->lt_denied);
}
out:
nfs4_unlock_state();
if (file_lock)
locks_free_lock(file_lock);
return status;
}

Expand All @@ -4272,7 +4297,7 @@ nfsd4_locku(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
{
struct nfs4_ol_stateid *stp;
struct file *filp = NULL;
struct file_lock file_lock;
struct file_lock *file_lock = NULL;
__be32 status;
int err;

Expand All @@ -4294,22 +4319,29 @@ nfsd4_locku(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
status = nfserr_lock_range;
goto out;
}
locks_init_lock(&file_lock);
file_lock.fl_type = F_UNLCK;
file_lock.fl_owner = (fl_owner_t)lockowner(stp->st_stateowner);
file_lock.fl_pid = current->tgid;
file_lock.fl_file = filp;
file_lock.fl_flags = FL_POSIX;
file_lock.fl_lmops = &nfsd_posix_mng_ops;
file_lock.fl_start = locku->lu_offset;

file_lock.fl_end = last_byte_offset(locku->lu_offset, locku->lu_length);
nfs4_transform_lock_offset(&file_lock);
file_lock = locks_alloc_lock();
if (!file_lock) {
dprintk("NFSD: %s: unable to allocate lock!\n", __func__);
status = nfserr_jukebox;
goto out;
}
locks_init_lock(file_lock);
file_lock->fl_type = F_UNLCK;
file_lock->fl_owner = (fl_owner_t)lockowner(stp->st_stateowner);
file_lock->fl_pid = current->tgid;
file_lock->fl_file = filp;
file_lock->fl_flags = FL_POSIX;
file_lock->fl_lmops = &nfsd_posix_mng_ops;
file_lock->fl_start = locku->lu_offset;

file_lock->fl_end = last_byte_offset(locku->lu_offset,
locku->lu_length);
nfs4_transform_lock_offset(file_lock);

/*
* Try to unlock the file in the VFS.
*/
err = vfs_lock_file(filp, F_SETLK, &file_lock, NULL);
err = vfs_lock_file(filp, F_SETLK, file_lock, NULL);
if (err) {
dprintk("NFSD: nfs4_locku: vfs_lock_file failed!\n");
goto out_nfserr;
Expand All @@ -4323,6 +4355,8 @@ nfsd4_locku(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
out:
if (!cstate->replay_owner)
nfs4_unlock_state();
if (file_lock)
locks_free_lock(file_lock);
return status;

out_nfserr:
Expand Down

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