From: Jeff Layton <jlayton@redhat.com>
To: bfields@fieldses.org
Cc: viro@ZenIV.linux.org.uk, linux-nfs@vger.kernel.org
Subject: [PATCH] knfsd: don't allocate file_locks on the stack
Date: Tue, 21 Aug 2012 08:03:32 -0400 [thread overview]
Message-ID: <1345550612-9744-1-git-send-email-jlayton@redhat.com> (raw)
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>
---
fs/nfsd/nfs4state.c | 118 +++++++++++++++++++++++++++++++++-------------------
1 file changed, 76 insertions(+), 42 deletions(-)
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 6e12fd5..07ded6d 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -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;
@@ -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;
@@ -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);
@@ -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;
@@ -4177,6 +4190,10 @@ out:
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;
}
@@ -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);
@@ -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");
@@ -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;
}
@@ -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;
@@ -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;
@@ -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:
--
1.7.11.4
next reply other threads:[~2012-08-21 12:03 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-21 12:03 Jeff Layton [this message]
2012-08-21 18:08 ` [PATCH] knfsd: don't allocate file_locks on the stack J. Bruce Fields
2012-08-21 19:07 ` J. Bruce Fields
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1345550612-9744-1-git-send-email-jlayton@redhat.com \
--to=jlayton@redhat.com \
--cc=bfields@fieldses.org \
--cc=linux-nfs@vger.kernel.org \
--cc=viro@ZenIV.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).