On Wed, Dec 06, 2006 at 02:57:22PM -0500, J. Bruce Fields wrote:
> On Wed, Dec 06, 2006 at 09:49:51AM -0600, David Teigland wrote:
> > The gfs side looks fine to me. Did you forget to call fl_notify from
> > gdlm_plock_callback() or am I missing something?
>
> Yes, looks like we missed something, thanks. This code's an rfc (not
> even tested), so don't apply it yet! What we should have there is
> something like:
>
> rv = op->info.rv;
>
> if (fl_notify(fl, NULL, rv)) {
> /* XXX: We need to cancel the lock here: */
> printk("gfs2 lock granted after lock request failed; dangling lock!\n");
> }
(And note in the patch I sent out I stuck this in the wrong place--in
the synchronous instead of the asynchronous code. So the patch should
have been something closer to the following.)
--b.
diff --git a/fs/gfs2/lm.c b/fs/gfs2/lm.c
index effe4a3..cf7fd52 100644
--- a/fs/gfs2/lm.c
+++ b/fs/gfs2/lm.c
@@ -197,6 +197,16 @@ int gfs2_lm_plock(struct gfs2_sbd *sdp, struct lm_lockname *name,
return error;
}
+int gfs2_lm_plock_async(struct gfs2_sbd *sdp, struct lm_lockname *name,
+ struct file *file, int cmd, struct file_lock *fl)
+{
+ int error = -EIO;
+ if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
+ error = sdp->sd_lockstruct.ls_ops->lm_plock_async(
+ sdp->sd_lockstruct.ls_lockspace, name, file, cmd, fl);
+ return error;
+}
+
int gfs2_lm_punlock(struct gfs2_sbd *sdp, struct lm_lockname *name,
struct file *file, struct file_lock *fl)
{
diff --git a/fs/gfs2/lm.h b/fs/gfs2/lm.h
index 21cdc30..1ddd1fd 100644
--- a/fs/gfs2/lm.h
+++ b/fs/gfs2/lm.h
@@ -34,6 +34,8 @@ int gfs2_lm_plock_get(struct gfs2_sbd *sdp, struct lm_lockname *name,
struct file *file, struct file_lock *fl);
int gfs2_lm_plock(struct gfs2_sbd *sdp, struct lm_lockname *name,
struct file *file, int cmd, struct file_lock *fl);
+int gfs2_lm_plock_async(struct gfs2_sbd *sdp, struct lm_lockname *name,
+ struct file *file, int cmd, struct file_lock *fl);
int gfs2_lm_punlock(struct gfs2_sbd *sdp, struct lm_lockname *name,
struct file *file, struct file_lock *fl);
void gfs2_lm_recovery_done(struct gfs2_sbd *sdp, unsigned int jid,
diff --git a/fs/gfs2/locking/dlm/lock_dlm.h b/fs/gfs2/locking/dlm/lock_dlm.h
index 33af707..82af860 100644
--- a/fs/gfs2/locking/dlm/lock_dlm.h
+++ b/fs/gfs2/locking/dlm/lock_dlm.h
@@ -179,6 +179,8 @@ int gdlm_plock_init(void);
void gdlm_plock_exit(void);
int gdlm_plock(void *, struct lm_lockname *, struct file *, int,
struct file_lock *);
+int gdlm_plock_async(void *, struct lm_lockname *, struct file *, int,
+ struct file_lock *);
int gdlm_plock_get(void *, struct lm_lockname *, struct file *,
struct file_lock *);
int gdlm_punlock(void *, struct lm_lockname *, struct file *,
diff --git a/fs/gfs2/locking/dlm/mount.c b/fs/gfs2/locking/dlm/mount.c
index cdd1694..4339e3f 100644
--- a/fs/gfs2/locking/dlm/mount.c
+++ b/fs/gfs2/locking/dlm/mount.c
@@ -244,6 +244,7 @@ const struct lm_lockops gdlm_ops = {
.lm_lock = gdlm_lock,
.lm_unlock = gdlm_unlock,
.lm_plock = gdlm_plock,
+ .lm_plock_async = gdlm_plock_async,
.lm_punlock = gdlm_punlock,
.lm_plock_get = gdlm_plock_get,
.lm_cancel = gdlm_cancel,
diff --git a/fs/gfs2/locking/dlm/plock.c b/fs/gfs2/locking/dlm/plock.c
index 7365aec..f91a18a 100644
--- a/fs/gfs2/locking/dlm/plock.c
+++ b/fs/gfs2/locking/dlm/plock.c
@@ -102,6 +102,94 @@ int gdlm_plock(void *lockspace, struct lm_lockname *name,
return rv;
}
+int gdlm_plock_async(void *lockspace, struct lm_lockname *name,
+ struct file *file, int cmd, struct file_lock *fl)
+{
+ struct gdlm_ls *ls = lockspace;
+ struct plock_op *op;
+ int rv;
+
+ op = kzalloc(sizeof(*op), GFP_KERNEL);
+ if (!op)
+ return -ENOMEM;
+
+ op->info.optype = GDLM_PLOCK_OP_LOCK;
+ op->info.pid = fl->fl_pid;
+ op->info.ex = (fl->fl_type == F_WRLCK);
+ op->info.wait = IS_SETLKW(cmd);
+ op->info.fsid = ls->id;
+ op->info.number = name->ln_number;
+ op->info.start = fl->fl_start;
+ op->info.end = fl->fl_end;
+ op->info.owner = (__u64)(long) fl->fl_owner;
+ if (fl->fl_lmops) {
+ op->info.callback = fl->fl_lmops->fl_notify;
+ /* might need to make a copy */
+ op->info.fl = fl;
+ op->info.file = file;
+ } else
+ op->info.callback = NULL;
+
+ send_op(op);
+
+ if (op->info.callback == NULL)
+ wait_event(recv_wq, (op->done != 0));
+ else
+ return -EINPROGRESS;
+
+ spin_lock(&ops_lock);
+ if (!list_empty(&op->list)) {
+ printk(KERN_INFO "plock op on list\n");
+ list_del(&op->list);
+ }
+ spin_unlock(&ops_lock);
+
+ rv = op->info.rv;
+
+ if (!rv) {
+ if (posix_lock_file_wait(file, fl) < 0)
+ log_error("gdlm_plock: vfs lock error %x,%llx",
+ name->ln_type,
+ (unsigned long long)name->ln_number);
+ }
+
+ kfree(op);
+ return rv;
+}
+
+static void gdlm_plock_callback(struct plock_op *op)
+{
+ struct file *file;
+ struct file_lock *fl;
+ int rv;
+
+ spin_lock(&ops_lock);
+ if (!list_empty(&op->list)) {
+ printk(KERN_INFO "plock op on list\n");
+ list_del(&op->list);
+ }
+ spin_unlock(&ops_lock);
+
+ rv = op->info.rv;
+
+ if (fl_notify(fl, NULL, rv)) {
+ /* XXX: We need to cancel the lock here: */
+ printk("gfs2 lock granted after lock request failed; dangling lock!\n");
+ }
+
+ if (!rv) {
+ /* check if the following are still valid or make a copy */
+ file = op->info.file;
+ fl = op->info.fl;
+
+ if (posix_lock_file_wait(file, fl) < 0)
+ log_error("gdlm_plock: vfs lock error file %p fl %p",
+ file, fl);
+ }
+
+ kfree(op);
+}
+
int gdlm_punlock(void *lockspace, struct lm_lockname *name,
struct file *file, struct file_lock *fl)
{
@@ -242,8 +330,12 @@ static ssize_t dev_write(struct file *file, const char __user *u, size_t count,
}
spin_unlock(&ops_lock);
- if (found)
- wake_up(&recv_wq);
+ if (found) {
+ if (op->info.callback)
+ gdlm_plock_callback(op);
+ else
+ wake_up(&recv_wq);
+ }
else
printk(KERN_INFO "gdlm dev_write no op %x %llx\n", info.fsid,
(unsigned long long)info.number);
diff --git a/fs/gfs2/ops_export.c b/fs/gfs2/ops_export.c
index 86127d9..80ca84f 100644
--- a/fs/gfs2/ops_export.c
+++ b/fs/gfs2/ops_export.c
@@ -22,6 +22,7 @@
#include "glock.h"
#include "glops.h"
#include "inode.h"
+#include "lm.h"
#include "ops_export.h"
#include "rgrp.h"
#include "util.h"
@@ -287,6 +288,56 @@ fail:
gfs2_glock_dq_uninit(&i_gh);
return ERR_PTR(error);
}
+/**
+ * gfs2_exp_lock - acquire/release a posix lock on a file
+ * @file: the file pointer
+ * @cmd: either modify or retrieve lock state, possibly wait
+ * @fl: type and range of lock
+ *
+ * Returns: errno
+ */
+
+static int gfs2_exp_lock(struct file *file, int cmd, struct file_lock *fl)
+{
+ struct gfs2_inode *ip = GFS2_I(file->f_mapping->host);
+ struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host);
+ struct lm_lockname name =
+ { .ln_number = ip->i_num.no_addr,
+ .ln_type = LM_TYPE_PLOCK };
+
+ if (!(fl->fl_flags & FL_POSIX))
+ return -ENOLCK;
+ if ((ip->i_di.di_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
+ return -ENOLCK;
+
+ if (sdp->sd_args.ar_localflocks) {
+ if (IS_GETLK(cmd)) {
+ struct file_lock tmp;
+ int ret;
+ ret = posix_test_lock(file, fl, &tmp);
+ fl->fl_type = F_UNLCK;
+ if (ret)
+ memcpy(fl, &tmp, sizeof(struct file_lock));
+ return 0;
+ } else {
+ return posix_lock_file_wait(file, fl);
+ }
+ }
+
+ if (IS_GETLK(cmd))
+ return gfs2_lm_plock_get(sdp, &name, file, fl);
+ else if (fl->fl_type == F_UNLCK)
+ return gfs2_lm_punlock(sdp, &name, file, fl);
+ else {
+ /* If fl_notify is set make an async lock request
+ and reply withh -EINPROGRESS. When lock is granted
+ the gfs2_lm_plock_async should callback to fl_notify */
+ if (fl->fl_lmops->fl_notify)
+ return gfs2_lm_plock_async(sdp, &name, file, cmd, fl);
+ else
+ return gfs2_lm_plock(sdp, &name, file, cmd, fl);
+ }
+}
struct export_operations gfs2_export_ops = {
.decode_fh = gfs2_decode_fh,
@@ -294,5 +345,6 @@ struct export_operations gfs2_export_ops = {
.get_name = gfs2_get_name,
.get_parent = gfs2_get_parent,
.get_dentry = gfs2_get_dentry,
+ .lock = gfs2_exp_lock,
};
diff --git a/include/linux/lm_interface.h b/include/linux/lm_interface.h
index 1418fdc..28d5445 100644
--- a/include/linux/lm_interface.h
+++ b/include/linux/lm_interface.h
@@ -213,6 +213,9 @@ struct lm_lockops {
int (*lm_plock) (void *lockspace, struct lm_lockname *name,
struct file *file, int cmd, struct file_lock *fl);
+ int (*lm_plock_async) (void *lockspace, struct lm_lockname *name,
+ struct file *file, int cmd, struct file_lock *fl);
+
int (*lm_punlock) (void *lockspace, struct lm_lockname *name,
struct file *file, struct file_lock *fl);
diff --git a/include/linux/lock_dlm_plock.h b/include/linux/lock_dlm_plock.h
index fc34151..809c5b7 100644
--- a/include/linux/lock_dlm_plock.h
+++ b/include/linux/lock_dlm_plock.h
@@ -35,6 +35,9 @@ struct gdlm_plock_info {
__u64 start;
__u64 end;
__u64 owner;
+ void *callback;
+ void *fl;
+ void *file;
};
#endif
-
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