From: Wendy Cheng <wcheng@redhat.com>
To: cluster-devel.redhat.com
Subject: [Cluster-devel] Re: [NFS] [PATCH 1/4 Revised] NLM failover - nlm_unlock
Date: Fri, 23 Mar 2007 18:55:17 -0400 [thread overview]
Message-ID: <46045AD5.9010702@redhat.com> (raw)
In-Reply-To: <17688.30411.484871.224188@cse.unsw.edu.au>
Neil Brown wrote:
> On Thursday September 14, wcheng at redhat.com wrote:
>
>> By writing exported filesytem id into /proc/fs/nfsd/nlm_unlock, this
>> patch walks thru lockd's global nlm_files list to release all the locks
>> associated with the particular id. It is used to enable NFS lock
>> failover with active-active clustered servers.
>>
>> Relevant steps:
>> 1) Exports filesystem with "fsid" option as:
>> /etc/exports entry> /mnt/ext3/exports *(fsid=1234,sync,rw)
>> 2) Drops locks based on fsid by:
>> shell> echo 1234 > /proc/fs/nfsd/nlm_unlock
>>
>
> I actually felt a bit more comfortable with the server-ip based
> approach, how I cannot really fault the fsid based approach, and it
> does seem to have some advantages, so I guess we go with it.
>
Neil,
I replaced the checking inside nlm_traverse_files with nlm_file_inuse()
as we discussed in:
http://sourceforge.net/mailarchive/forum.php?thread_id=31885384&forum_id=4930
If a separate patch is a better idea, feel free to yank it out. The code
is based on 2.6.21.rc4 kernel and can be used independently (without
other NLM failover patches). We submit it earlier (others still being
worked on) to avoid the tedious rebase efforts. There are also customer
requests from our distribution to ask for this function in a single
server (no cluster) environment.
-- Wendy
-------------- next part --------------
A non-text attachment was scrubbed...
Name: nlm_unlock.patch
Type: text/x-patch
Size: 8956 bytes
Desc: not available
URL: <http://listman.redhat.com/archives/cluster-devel/attachments/20070323/c90f29b2/attachment.bin>
WARNING: multiple messages have this Message-ID (diff)
From: Wendy Cheng <wcheng@redhat.com>
To: Neil Brown <neilb@suse.de>
Cc: cluster-devel@redhat.com, lhh@redhat.com, nfs@lists.sourceforge.net
Subject: Re: [PATCH 1/4 Revised] NLM failover - nlm_unlock
Date: Fri, 23 Mar 2007 18:55:17 -0400 [thread overview]
Message-ID: <46045AD5.9010702@redhat.com> (raw)
In-Reply-To: <17688.30411.484871.224188@cse.unsw.edu.au>
[-- Attachment #1: Type: text/plain, Size: 1360 bytes --]
Neil Brown wrote:
> On Thursday September 14, wcheng@redhat.com wrote:
>
>> By writing exported filesytem id into /proc/fs/nfsd/nlm_unlock, this
>> patch walks thru lockd's global nlm_files list to release all the locks
>> associated with the particular id. It is used to enable NFS lock
>> failover with active-active clustered servers.
>>
>> Relevant steps:
>> 1) Exports filesystem with "fsid" option as:
>> /etc/exports entry> /mnt/ext3/exports *(fsid=1234,sync,rw)
>> 2) Drops locks based on fsid by:
>> shell> echo 1234 > /proc/fs/nfsd/nlm_unlock
>>
>
> I actually felt a bit more comfortable with the server-ip based
> approach, how I cannot really fault the fsid based approach, and it
> does seem to have some advantages, so I guess we go with it.
>
Neil,
I replaced the checking inside nlm_traverse_files with nlm_file_inuse()
as we discussed in:
http://sourceforge.net/mailarchive/forum.php?thread_id=31885384&forum_id=4930
If a separate patch is a better idea, feel free to yank it out. The code
is based on 2.6.21.rc4 kernel and can be used independently (without
other NLM failover patches). We submit it earlier (others still being
worked on) to avoid the tedious rebase efforts. There are also customer
requests from our distribution to ask for this function in a single
server (no cluster) environment.
-- Wendy
[-- Attachment #2: nlm_unlock.patch --]
[-- Type: text/x-patch, Size: 8956 bytes --]
Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Signed-off-by: Lon Hohberger <lhh@redhat.com>
fs/lockd/svcsubs.c | 64 ++++++++++++++++++++++++++++++++++++++++++--
fs/nfsd/nfsctl.c | 28 +++++++++++++++++++
include/linux/lockd/bind.h | 1
include/linux/lockd/lockd.h | 4 ++
include/linux/nfsd/nfsfh.h | 29 +++++++++++++++++++
5 files changed, 124 insertions(+), 2 deletions(-)
--- gfs2-nmw/include/linux/nfsd/nfsfh.h 2007-03-19 14:18:53.000000000 -0400
+++ linux/include/linux/nfsd/nfsfh.h 2007-03-20 15:45:29.000000000 -0400
@@ -254,6 +254,35 @@ static inline int key_len(int type)
}
}
+/*
+ * Used by lockd to get FSID_NUM fsid from nfs_fh, logic based on fh_verify
+ * return 0 if not found
+ * 1 if *fsid contain a valid fsid
+ */
+static inline int get_fsid(struct nfs_fh *fh, unsigned int *fsid)
+{
+ struct nfs_fhbase_new *fh_base = (struct nfs_fhbase_new *) fh->data;
+ int data_left = fh->size/4;
+
+ /* From fb_version to fb_auth - at least two u32 */
+ if (data_left < 2)
+ return 0;
+
+ /* For various types, check out
+ * inlcude/linux/nfsd/nfsfsh.h
+ */
+ if ((fh_base->fb_version != 1) ||
+ (fh_base->fb_auth_type != 0) ||
+ (fh_base->fb_fsid_type != FSID_NUM))
+ return 0;
+
+ /* The fb_auth is 0 bytes long - imply fb_auth[0] has
+ * fsid value.
+ */
+ *fsid = (int) fh_base->fb_auth[0];
+ return 1;
+}
+
/*
* Shorthand for dprintk()'s
*/
--- gfs2-nmw/include/linux/lockd/lockd.h 2007-03-19 14:18:42.000000000 -0400
+++ linux/include/linux/lockd/lockd.h 2007-03-21 15:01:57.000000000 -0400
@@ -202,6 +202,8 @@ void nlm_release_file(struct nlm_file
void nlmsvc_mark_resources(void);
void nlmsvc_free_host_resources(struct nlm_host *);
void nlmsvc_invalidate_all(void);
+int nlmsvc_same_fsid(struct nlm_host *, struct nlm_host *);
+int nlmsvc_fo_unlock(int *fsid);
static __inline__ struct inode *
nlmsvc_file_inode(struct nlm_file *file)
--- gfs2-nmw/fs/lockd/svcsubs.c 2007-03-19 14:17:52.000000000 -0400
+++ linux/fs/lockd/svcsubs.c 2007-03-23 17:46:10.000000000 -0400
@@ -18,6 +18,7 @@
#include <linux/lockd/lockd.h>
#include <linux/lockd/share.h>
#include <linux/lockd/sm_inter.h>
+#include <linux/module.h> /* EXPORT_SYMBOL */
#define NLMDBG_FACILITY NLMDBG_SVCSUBS
@@ -179,6 +180,7 @@ again:
if (match(lockhost, host)) {
struct file_lock lock = *fl;
+ dprintk("nlm_traverse_locks: match-delete the lock\n");
lock.fl_type = F_UNLCK;
lock.fl_start = 0;
lock.fl_end = OFFSET_MAX;
@@ -194,12 +196,41 @@ again:
return 0;
}
+static inline int
+nlm_fo_fsid_match(struct nlm_host *host, struct nlm_file *file)
+{
+ struct nfs_fh *fh = &file->f_handle;
+ unsigned int fsid_found, fsid_passed = *((unsigned int *)host);
+
+ nlm_debug_print_fh("nlm_fo_check_fsid", fh);
+
+ /* yank fsid out of file handle */
+ if (get_fsid(fh, &fsid_found) && (fsid_found == fsid_passed))
+ return 1;
+
+ /* no match */
+ return 0;
+}
+
/*
* Inspect a single file
*/
static inline int
nlm_inspect_file(struct nlm_host *host, struct nlm_file *file, nlm_host_match_fn_t match)
{
+ /* Cluster failover has timing constraints. There is a slight
+ * performance hit if nlm_fo_check_fsid()is implemented as a match
+ * fn (since it will be invoked multiple times later). Instead, we
+ * we add fsid-matching logic into the following clause.
+ * If fsid matches, nlmsvc_same_fsid will always return true.
+ */
+ dprintk("nlm_inspect_files: file=%p\n", file);
+ if (unlikely(match == nlmsvc_same_fsid)) {
+ if (!nlm_fo_fsid_match(host, file))
+ return 0;
+ dprintk("nlm_fo fsid matches\n");
+ }
+
nlmsvc_traverse_blocks(host, file, match);
nlmsvc_traverse_shares(host, file, match);
return nlm_traverse_locks(host, file, match);
@@ -250,8 +281,7 @@ nlm_traverse_files(struct nlm_host *host
mutex_lock(&nlm_file_mutex);
file->f_count--;
/* No more references to this file. Let go of it. */
- if (list_empty(&file->f_blocks) && !file->f_locks
- && !file->f_shares && !file->f_count) {
+ if (!nlm_file_inuse(file)) {
hlist_del(&file->f_list);
nlmsvc_ops->fclose(file->f_file);
kfree(file);
@@ -301,7 +331,14 @@ nlm_release_file(struct nlm_file *file)
* nlmsvc_is_client:
* returns 1 iff the host is a client.
* Used by nlmsvc_invalidate_all
+ *
+ * nlmsvc_same_fsid:
+ * always returns 1 if invoked. The real job is done by
+ * nlm_fo_check_fsid(). It should release all resources
+ * bound to a specific nfs export, identified by exported
+ * fsid.
*/
+
static int
nlmsvc_mark_host(struct nlm_host *host, struct nlm_host *dummy)
{
@@ -330,6 +367,15 @@ nlmsvc_is_client(struct nlm_host *host,
return 0;
}
+/* To fit the logic into current lockd code structure, we add a
+ * little wrapper function here. The real matching task should be
+ * carried out by nlm_fo_check_fsid().
+ */
+int nlmsvc_same_fsid(struct nlm_host *dummy1, struct nlm_host *dummy2)
+{
+ return 1;
+}
+
/*
* Mark all hosts that still hold resources
*/
@@ -370,3 +416,17 @@ nlmsvc_invalidate_all(void)
*/
nlm_traverse_files(NULL, nlmsvc_is_client);
}
+
+EXPORT_SYMBOL(nlmsvc_fo_unlock);
+
+/*
+ * Release locks associated with an export fsid upon failover
+ * invoked via nfsd nfsctl call (write_fo_unlock).
+ */
+int
+nlmsvc_fo_unlock(int *fsid)
+{
+ return (nlm_traverse_files((struct nlm_host*)fsid, nlmsvc_same_fsid));
+}
+
+
--- gfs2-nmw/fs/nfsd/nfsctl.c 2007-03-19 14:18:04.000000000 -0400
+++ linux/fs/nfsd/nfsctl.c 2007-03-23 18:24:47.000000000 -0400
@@ -36,6 +36,7 @@
#include <linux/nfsd/xdr.h>
#include <linux/nfsd/syscall.h>
#include <linux/nfsd/interface.h>
+#include <linux/lockd/bind.h>
#include <asm/uaccess.h>
@@ -53,6 +54,7 @@ enum {
NFSD_Getfs,
NFSD_List,
NFSD_Fh,
+ NFSD_NlmUnlock,
NFSD_Threads,
NFSD_Pool_Threads,
NFSD_Versions,
@@ -79,6 +81,7 @@ static ssize_t write_unexport(struct fil
static ssize_t write_getfd(struct file *file, char *buf, size_t size);
static ssize_t write_getfs(struct file *file, char *buf, size_t size);
static ssize_t write_filehandle(struct file *file, char *buf, size_t size);
+static ssize_t write_fo_unlock(struct file *file, char *buf, size_t size);
static ssize_t write_threads(struct file *file, char *buf, size_t size);
static ssize_t write_pool_threads(struct file *file, char *buf, size_t size);
static ssize_t write_versions(struct file *file, char *buf, size_t size);
@@ -98,6 +101,7 @@ static ssize_t (*write_op[])(struct file
[NFSD_Getfd] = write_getfd,
[NFSD_Getfs] = write_getfs,
[NFSD_Fh] = write_filehandle,
+ [NFSD_NlmUnlock] = write_fo_unlock,
[NFSD_Threads] = write_threads,
[NFSD_Pool_Threads] = write_pool_threads,
[NFSD_Versions] = write_versions,
@@ -345,6 +349,29 @@ static ssize_t write_filehandle(struct f
return mesg - buf;
}
+static ssize_t write_fo_unlock(struct file *file, char *buf, size_t size)
+{
+ char *mesg = buf;
+ int fsid, rc;
+
+ if (size <= 0) return -EINVAL;
+
+ /* convert string into a valid fsid */
+ rc = get_int(&mesg, &fsid);
+ if (rc)
+ return rc;
+
+ /* call nlm to release the locks - fsid is passed by reference
+ * to allow other routine uses NULL pointer. */
+ rc = nlmsvc_fo_unlock(&fsid);
+ if (rc)
+ return rc;
+
+ /* done */
+ sprintf(buf, "nlm_fo fsid=%d released locks\n", fsid);
+ return strlen(buf);
+}
+
extern int nfsd_nrthreads(void);
static ssize_t write_threads(struct file *file, char *buf, size_t size)
@@ -648,6 +675,7 @@ static int nfsd_fill_super(struct super_
[NFSD_Getfs] = {".getfs", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_List] = {"exports", &exports_operations, S_IRUGO},
[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
+ [NFSD_NlmUnlock] = {"nlm_unlock", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},
[NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
--- gfs2-nmw/include/linux/lockd/bind.h 2007-03-19 14:18:42.000000000 -0400
+++ linux/include/linux/lockd/bind.h 2007-03-21 14:54:07.000000000 -0400
@@ -37,5 +37,6 @@ extern struct nlmsvc_binding * nlmsvc_op
extern int nlmclnt_proc(struct inode *, int, struct file_lock *);
extern int lockd_up(int proto);
extern void lockd_down(void);
+extern int nlmsvc_fo_unlock(int *fsid);
#endif /* LINUX_LOCKD_BIND_H */
--- gfs2-nmw/include/linux/lockd/lockd.h 2007-03-19 14:18:42.000000000 -0400
+++ linux/include/linux/lockd/lockd.h 2007-03-21 15:01:57.000000000 -0400
@@ -202,6 +202,8 @@ void nlm_release_file(struct nlm_file
void nlmsvc_mark_resources(void);
void nlmsvc_free_host_resources(struct nlm_host *);
void nlmsvc_invalidate_all(void);
+int nlmsvc_same_fsid(struct nlm_host *, struct nlm_host *);
+int nlmsvc_fo_unlock(int *fsid);
static __inline__ struct inode *
nlmsvc_file_inode(struct nlm_file *file)
[-- Attachment #3: Type: text/plain, Size: 345 bytes --]
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys-and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
[-- Attachment #4: Type: text/plain, Size: 140 bytes --]
_______________________________________________
NFS maillist - NFS@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nfs
next prev parent reply other threads:[~2007-03-23 22:55 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-09-14 4:44 [Cluster-devel] [PATCH 1/4 Revised] NLM failover - nlm_unlock Wendy Cheng
2006-09-14 4:44 ` Wendy Cheng
[not found] ` <message from Wendy Cheng on Thursday September 14>
2006-09-26 0:39 ` [Cluster-devel] Re: [NFS] " Neil Brown
2006-09-26 0:39 ` Neil Brown
2007-03-23 22:55 ` Wendy Cheng [this message]
2007-03-23 22:55 ` Wendy Cheng
2006-09-26 0:46 ` [Cluster-devel] Re: [NFS] [PATCH 2/4 Revised] NLM failover - nlm_set_igrace Neil Brown
2006-09-26 0:46 ` Neil Brown
2007-03-26 22:21 ` [Cluster-devel] Re: [NFS] " Wendy Cheng
2007-03-26 22:21 ` Wendy Cheng
2007-03-28 2:45 ` J. Bruce Fields
2007-03-28 2:45 ` [Cluster-devel] Re: [NFS] " J. Bruce Fields
2007-03-28 5:32 ` Wendy Cheng
2007-03-28 5:32 ` Wendy Cheng
2007-03-28 23:28 ` J. Bruce Fields
2007-03-28 23:28 ` [Cluster-devel] Re: [NFS] " J. Bruce Fields
2007-03-29 5:31 ` Wendy Cheng
2007-03-29 5:31 ` Wendy Cheng
2006-09-26 0:54 ` [Cluster-devel] Re: [NFS] [PATCH 3/4 Revised] NLM failover - statd changes Neil Brown
2006-09-26 0:54 ` Neil Brown
2006-09-26 13:42 ` [Cluster-devel] Re: [NFS] " Wendy Cheng
2006-09-26 13:42 ` Wendy Cheng
-- strict thread matches above, loose matches on Subject: below --
2006-09-14 4:48 [Cluster-devel] [PATCH 2/4 Revised] NLM failover - nlm_set_igrace Wendy Cheng
2006-09-14 4:48 ` Wendy Cheng
2006-09-14 4:50 [Cluster-devel] [PATCH 3/4 Revised] NLM failover - statd changes Wendy Cheng
2006-09-14 4:50 ` Wendy Cheng
2007-03-27 22:46 ` [Cluster-devel] " Wendy Cheng
2007-03-27 22:46 ` Wendy Cheng
2007-03-30 7:20 ` Wendy Cheng
2007-03-30 7:25 ` Wendy Cheng
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=46045AD5.9010702@redhat.com \
--to=wcheng@redhat.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.