From 17efa372cfe4d189705edf6cd4fbe283827a5dc7 Mon Sep 17 00:00:00 2001 From: Wendy Cheng Date: Thu, 17 Jan 2008 11:10:12 -0500 Subject: [PATCH] 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(-) --- fs/lockd/svcsubs.c | 37 ++++++++++++++++++++++++++++++++----- fs/nfsd/nfsctl.c | 32 ++++++++++++++++++++++++++++++++ include/linux/lockd/lockd.h | 1 + 3 files changed, 65 insertions(+), 5 deletions(-) diff --git a/fs/lockd/svcsubs.c b/fs/lockd/svcsubs.c index 1adcf93cb6e6..d1c48b539df8 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 +385,26 @@ 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_match_sb(void *datap, struct nlm_file *file) +{ + struct super_block *sb = datap; + + return sb == file->f_file->f_path.mnt->mnt_sb; +} + +int +nlmsvc_unlock_all_by_sb(struct super_block *sb) +{ + int ret; + + ret = nlm_traverse_files(sb, nlmsvc_always_match, nlmsvc_match_sb); + return ret ? -EIO : 0; } +EXPORT_SYMBOL_GPL(nlmsvc_unlock_all_by_sb); static int nlmsvc_match_ip(void *datap, struct nlm_host *host) @@ -391,7 +418,7 @@ int nlmsvc_unlock_all_by_ip(__be32 server_addr) { int ret; - ret = nlm_traverse_files(&server_addr, nlmsvc_match_ip); + ret = nlm_traverse_files(&server_addr, nlmsvc_match_ip, NULL); return ret ? -EIO : 0; } diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index 7706f6c9ab8a..42f3820ee8f5 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -56,6 +56,7 @@ enum { NFSD_List, NFSD_Fh, NFSD_FO_UnlockIP, + NFSD_FO_UnlockFS, NFSD_Threads, NFSD_Pool_Threads, NFSD_Versions, @@ -93,6 +94,7 @@ 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, @@ -104,6 +106,7 @@ 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, @@ -329,6 +332,33 @@ static ssize_t failover_unlock_ip(struct file *file, char *buf, size_t size) return nlmsvc_unlock_all_by_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_unlock_all_by_sb(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: @@ -733,6 +763,8 @@ 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 bcb93fc1fce7..102d928f7206 100644 --- a/include/linux/lockd/lockd.h +++ b/include/linux/lockd/lockd.h @@ -223,6 +223,7 @@ void nlmsvc_invalidate_all(void); /* * Cluster failover support */ +int nlmsvc_unlock_all_by_sb(struct super_block *sb); int nlmsvc_unlock_all_by_ip(__be32 server_addr); static inline struct inode *nlmsvc_file_inode(struct nlm_file *file) -- 2.20.1