From: "J. Bruce Fields" Subject: Re: [PATCH] lockd: unlock lockd locks held for a certain filesystem Date: Wed, 23 Apr 2008 17:02:27 -0400 Message-ID: <20080423210227.GF8302@fieldses.org> References: <480655E7.30800@gmail.com> <20080417215222.GK9912@fieldses.org> <4808A9DE.9040304@gmail.com> <20080418181918.GB24552@fieldses.org> <20080422231520.GI21770@fieldses.org> <20080422231729.GJ21770@fieldses.org> <20080422231855.GK21770@fieldses.org> <20080423074422.GA23518@lst.de> <20080423171240.GG31576@fieldses.org> <480F9E6F.4070204@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Christoph Hellwig , nfs@lists.sourceforge.net, linux-nfs@vger.kernel.org, Lon Hohberger To: Wendy Cheng Return-path: Received: from mail.fieldses.org ([66.93.2.214]:42663 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753894AbYDWVCd (ORCPT ); Wed, 23 Apr 2008 17:02:33 -0400 In-Reply-To: <480F9E6F.4070204@gmail.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Wed, Apr 23, 2008 at 04:39:11PM -0400, Wendy Cheng wrote: > #if defined(BRUCE_CHECK_THIS_OUT) > error = nlmsvc_failover_path(nd.path.mnt->mnt_sb); > #else > error = nlmsvc_failover_path(nd.mnt->mnt_sb); > #endif The vfsmount and dentry got moved into the path argument sometime in the last kernel version or so. Is there a macro defining the latter as a shortcut for the former? I didn't see one. --b. > > -- Wendy > > ---------- based on the following email ---------------------------- > > J. Bruce Fields wrote: >> On Wed, Apr 23, 2008 at 09:44:22AM +0200, Christoph Hellwig wrote: >> >>> Please don't pass down the nameidata, but just the super_block. That's >>> all we need in the lower layer functions. >>> >> >> Yep, I agree that's nicer; here's the result. >> >> --b. >> >> commit 26a816586b71877d8a84fbb436373099384e328b >> Author: Wendy Cheng >> Date: Thu Jan 17 11:10:12 2008 -0500 >> >> lockd: unlock lockd locks held for a certain filesystem >> Add /proc/fs/nfsd/unlock_filesystem, which allows e.g.: >> shell> echo /mnt/sfs1 > /proc/fs/nfsd/unlock_filesystem >> so that a filesystem can be unmounted before allowing a peer >> nfsd to >> take over nfs service for the filesystem. >> Signed-off-by: S. Wendy Cheng >> Cc: Lon Hohberger >> Cc: Christoph Hellwig >> Signed-off-by: J. Bruce Fields >> fs/lockd/svcsubs.c | 66 >> +++++++++++++++++++++++++++++++++++++++----- >> fs/nfsd/nfsctl.c | 65 +++++++++++++++++++++++++++++++++++++++++++ >> include/linux/lockd/lockd.h | 7 ++++ >> 3 files changed, 131 insertions(+), 7 deletions(-) >> >> diff --git a/fs/lockd/svcsubs.c b/fs/lockd/svcsubs.c >> index e12daba..dcdcff6 100644 >> --- a/fs/lockd/svcsubs.c >> +++ b/fs/lockd/svcsubs.c >> @@ -196,6 +196,12 @@ again: >> return 0; >> } >> +static int >> +nlmsvc_always_match(void *dummy1, struct nlm_host *dummy2) >> +{ >> + return 1; >> +} >> + >> /* >> * Inspect a single file >> */ >> @@ -232,7 +238,8 @@ nlm_file_inuse(struct nlm_file *file) >> * Loop over all files in the file table. >> */ >> static int >> -nlm_traverse_files(void *data, nlm_host_match_fn_t match) >> +nlm_traverse_files(void *data, nlm_host_match_fn_t match, >> + int (*is_failover_file)(void *data, struct nlm_file *file)) >> { >> struct hlist_node *pos, *next; >> struct nlm_file *file; >> @@ -241,6 +248,8 @@ nlm_traverse_files(void *data, nlm_host_match_fn_t match) >> mutex_lock(&nlm_file_mutex); >> for (i = 0; i < FILE_NRHASH; i++) { >> hlist_for_each_entry_safe(file, pos, next, &nlm_files[i], f_list) { >> + if (is_failover_file && !is_failover_file(data, file)) >> + continue; >> file->f_count++; >> mutex_unlock(&nlm_file_mutex); >> @@ -345,7 +354,7 @@ void >> nlmsvc_mark_resources(void) >> { >> dprintk("lockd: nlmsvc_mark_resources\n"); >> - nlm_traverse_files(NULL, nlmsvc_mark_host); >> + nlm_traverse_files(NULL, nlmsvc_mark_host, NULL); >> } >> /* >> @@ -356,7 +365,7 @@ nlmsvc_free_host_resources(struct nlm_host *host) >> { >> dprintk("lockd: nlmsvc_free_host_resources\n"); >> - if (nlm_traverse_files(host, nlmsvc_same_host)) { >> + if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) { >> printk(KERN_WARNING >> "lockd: couldn't remove all locks held by %s\n", >> host->h_name); >> @@ -376,8 +385,27 @@ nlmsvc_invalidate_all(void) >> * turn, which is about as inefficient as it gets. >> * Now we just do it once in nlm_traverse_files. >> */ >> - nlm_traverse_files(NULL, nlmsvc_is_client); >> + nlm_traverse_files(NULL, nlmsvc_is_client, NULL); >> +} >> + >> +static int >> +nlmsvc_failover_file_ok_path(void *datap, struct nlm_file *file) >> +{ >> + struct super_block *sb = datap; >> + >> + return sb == file->f_file->f_path.mnt->mnt_sb; >> +} >> + >> +int >> +nlmsvc_failover_path(struct super_block *sb) >> +{ >> + int ret; >> + >> + ret = nlm_traverse_files(sb, nlmsvc_always_match, >> + nlmsvc_failover_file_ok_path); >> + return ret ? -EIO : 0; >> } >> +EXPORT_SYMBOL_GPL(nlmsvc_failover_path); >> static int >> nlmsvc_failover_file_ok_ip(void *datap, struct nlm_host *host) >> @@ -391,7 +419,8 @@ int >> nlmsvc_failover_ip(__be32 server_addr) >> { >> int ret; >> - ret = nlm_traverse_files(&server_addr, nlmsvc_failover_file_ok_ip); >> + ret = nlm_traverse_files(&server_addr, nlmsvc_failover_file_ok_ip, >> + NULL); >> return ret ? -EIO : 0; >> } >> diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c >> index 02c3949..b4ca5c9 100644 >> --- a/fs/nfsd/nfsctl.c >> +++ b/fs/nfsd/nfsctl.c >> @@ -55,6 +55,7 @@ enum { >> NFSD_List, >> NFSD_Fh, >> NFSD_FO_UnlockIP, >> + NFSD_FO_UnlockFS, >> NFSD_Threads, >> NFSD_Pool_Threads, >> NFSD_Versions, >> @@ -92,6 +93,7 @@ static ssize_t write_recoverydir(struct file *file, char *buf, size_t size); >> #endif >> static ssize_t failover_unlock_ip(struct file *file, char *buf, >> size_t size); >> +static ssize_t failover_unlock_fs(struct file *file, char *buf, size_t size); >> static ssize_t (*write_op[])(struct file *, char *, size_t) = { >> [NFSD_Svc] = write_svc, >> @@ -103,6 +105,7 @@ static ssize_t (*write_op[])(struct file *, char *, size_t) = { >> [NFSD_Getfs] = write_getfs, >> [NFSD_Fh] = write_filehandle, >> [NFSD_FO_UnlockIP] = failover_unlock_ip, >> + [NFSD_FO_UnlockFS] = failover_unlock_fs, >> [NFSD_Threads] = write_threads, >> [NFSD_Pool_Threads] = write_pool_threads, >> [NFSD_Versions] = write_versions, >> @@ -319,6 +322,33 @@ static ssize_t failover_unlock_ip(struct file *file, char *buf, size_t size) >> return nlmsvc_failover_ip(server_ip); >> } >> +static ssize_t failover_unlock_fs(struct file *file, char *buf, >> size_t size) >> +{ >> + struct nameidata nd; >> + char *fo_path; >> + int error; >> + >> + /* sanity check */ >> + if (size == 0) >> + return -EINVAL; >> + >> + if (buf[size-1] != '\n') >> + return -EINVAL; >> + >> + fo_path = buf; >> + if (qword_get(&buf, fo_path, size) < 0) >> + return -EINVAL; >> + >> + error = path_lookup(fo_path, 0, &nd); >> + if (error) >> + return error; >> + >> + error = nlmsvc_failover_path(nd.path.mnt->mnt_sb); >> + >> + path_put(&nd.path); >> + return error; >> +} >> + >> static ssize_t write_filehandle(struct file *file, char *buf, size_t size) >> { >> /* request is: >> @@ -729,6 +759,8 @@ static int nfsd_fill_super(struct super_block * sb, void * data, int silent) >> [NFSD_List] = {"exports", &exports_operations, S_IRUGO}, >> [NFSD_FO_UnlockIP] = {"unlock_ip", >> &transaction_ops, S_IWUSR|S_IRUSR}, >> + [NFSD_FO_UnlockFS] = {"unlock_filesystem", >> + &transaction_ops, S_IWUSR|S_IRUSR}, >> [NFSD_Fh] = {"filehandle", &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}, >> diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h >> index f06d2db..7cd9c8e 100644 >> --- a/include/linux/lockd/lockd.h >> +++ b/include/linux/lockd/lockd.h >> @@ -220,6 +220,7 @@ void nlmsvc_invalidate_all(void); >> /* >> * Cluster failover support >> */ >> +int nlmsvc_failover_path(struct super_block *sb); >> int nlmsvc_failover_ip(__be32 server_addr); >> static __inline__ struct inode * >> >