From f2af793db02d2c2f677bdb5bf8e0efdcbf9c0256 Mon Sep 17 00:00:00 2001 From: Olaf Kirch Date: Wed, 4 Oct 2006 02:15:59 -0700 Subject: [PATCH] [PATCH] knfsd: lockd: make nlm_traverse_* more flexible This patch makes nlm_traverse{locks,blocks,shares} and friends use a function pointer rather than a "action" enum. This function pointer is given two nlm_hosts (one given by the caller, the other taken from the lock/block/share currently visited), and is free to do with them as it wants. If it returns a non-zero value, the lockd/block/share is released. Signed-off-by: Olaf Kirch Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/lockd/svclock.c | 33 +++--------- fs/lockd/svcshare.c | 20 +++---- fs/lockd/svcsubs.c | 105 ++++++++++++++++++++++++++---------- include/linux/lockd/lockd.h | 15 +++--- include/linux/lockd/share.h | 3 +- 5 files changed, 102 insertions(+), 74 deletions(-) diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c index 7209712f383..1f91567a1b8 100644 --- a/fs/lockd/svclock.c +++ b/fs/lockd/svclock.c @@ -265,24 +265,20 @@ static void nlmsvc_release_block(struct nlm_block *block) kref_put(&block->b_count, nlmsvc_free_block); } -static void nlmsvc_act_mark(struct nlm_host *host, struct nlm_file *file) -{ - struct nlm_block *block; - - down(&file->f_sema); - list_for_each_entry(block, &file->f_blocks, b_flist) - block->b_host->h_inuse = 1; - up(&file->f_sema); -} - -static void nlmsvc_act_unlock(struct nlm_host *host, struct nlm_file *file) +/* + * Loop over all blocks and delete blocks held by + * a matching host. + */ +void nlmsvc_traverse_blocks(struct nlm_host *host, + struct nlm_file *file, + nlm_host_match_fn_t match) { struct nlm_block *block, *next; restart: down(&file->f_sema); list_for_each_entry_safe(block, next, &file->f_blocks, b_flist) { - if (host != NULL && host != block->b_host) + if (!match(block->b_host, host)) continue; /* Do not destroy blocks that are not on * the global retry list - why? */ @@ -297,19 +293,6 @@ restart: up(&file->f_sema); } -/* - * Loop over all blocks and perform the action specified. - * (NLM_ACT_CHECK handled by nlmsvc_inspect_file). - */ -void -nlmsvc_traverse_blocks(struct nlm_host *host, struct nlm_file *file, int action) -{ - if (action == NLM_ACT_MARK) - nlmsvc_act_mark(host, file); - else - nlmsvc_act_unlock(host, file); -} - /* * Initialize arguments for GRANTED call. The nlm_rqst structure * has been cleared already. diff --git a/fs/lockd/svcshare.c b/fs/lockd/svcshare.c index 27288c83da9..b9926ce8782 100644 --- a/fs/lockd/svcshare.c +++ b/fs/lockd/svcshare.c @@ -85,24 +85,20 @@ nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file, } /* - * Traverse all shares for a given file (and host). - * NLM_ACT_CHECK is handled by nlmsvc_inspect_file. + * Traverse all shares for a given file, and delete + * those owned by the given (type of) host */ -void -nlmsvc_traverse_shares(struct nlm_host *host, struct nlm_file *file, int action) +void nlmsvc_traverse_shares(struct nlm_host *host, struct nlm_file *file, + nlm_host_match_fn_t match) { struct nlm_share *share, **shpp; shpp = &file->f_shares; while ((share = *shpp) != NULL) { - if (action == NLM_ACT_MARK) - share->s_host->h_inuse = 1; - else if (action == NLM_ACT_UNLOCK) { - if (host == NULL || host == share->s_host) { - *shpp = share->s_next; - kfree(share); - continue; - } + if (match(share->s_host, host)) { + *shpp = share->s_next; + kfree(share); + continue; } shpp = &share->s_next; } diff --git a/fs/lockd/svcsubs.c b/fs/lockd/svcsubs.c index 91731353dfa..bb13a48210f 100644 --- a/fs/lockd/svcsubs.c +++ b/fs/lockd/svcsubs.c @@ -165,7 +165,8 @@ nlm_delete_file(struct nlm_file *file) * action. */ static int -nlm_traverse_locks(struct nlm_host *host, struct nlm_file *file, int action) +nlm_traverse_locks(struct nlm_host *host, struct nlm_file *file, + nlm_host_match_fn_t match) { struct inode *inode = nlmsvc_file_inode(file); struct file_lock *fl; @@ -179,17 +180,11 @@ again: /* update current lock count */ file->f_locks++; + lockhost = (struct nlm_host *) fl->fl_owner; - if (action == NLM_ACT_MARK) - lockhost->h_inuse = 1; - else if (action == NLM_ACT_CHECK) - return 1; - else if (action == NLM_ACT_UNLOCK) { + if (match(lockhost, host)) { struct file_lock lock = *fl; - if (host && lockhost != host) - continue; - lock.fl_type = F_UNLCK; lock.fl_start = 0; lock.fl_end = OFFSET_MAX; @@ -206,27 +201,42 @@ again: } /* - * Operate on a single file + * Inspect a single file + */ +static inline int +nlm_inspect_file(struct nlm_host *host, struct nlm_file *file, nlm_host_match_fn_t match) +{ + nlmsvc_traverse_blocks(host, file, match); + nlmsvc_traverse_shares(host, file, match); + return nlm_traverse_locks(host, file, match); +} + +/* + * Quick check whether there are still any locks, blocks or + * shares on a given file. */ static inline int -nlm_inspect_file(struct nlm_host *host, struct nlm_file *file, int action) +nlm_file_inuse(struct nlm_file *file) { - if (action == NLM_ACT_CHECK) { - /* Fast path for mark and sweep garbage collection */ - if (file->f_count || list_empty(&file->f_blocks) || file->f_shares) + struct inode *inode = nlmsvc_file_inode(file); + struct file_lock *fl; + + if (file->f_count || !list_empty(&file->f_blocks) || file->f_shares) + return 1; + + for (fl = inode->i_flock; fl; fl = fl->fl_next) { + if (fl->fl_lmops == &nlmsvc_lock_operations) return 1; - } else { - nlmsvc_traverse_blocks(host, file, action); - nlmsvc_traverse_shares(host, file, action); } - return nlm_traverse_locks(host, file, action); + file->f_locks = 0; + return 0; } /* * Loop over all files in the file table. */ static int -nlm_traverse_files(struct nlm_host *host, int action) +nlm_traverse_files(struct nlm_host *host, nlm_host_match_fn_t match) { struct hlist_node *pos, *next; struct nlm_file *file; @@ -240,7 +250,7 @@ nlm_traverse_files(struct nlm_host *host, int action) /* Traverse locks, blocks and shares of this file * and update file->f_locks count */ - if (nlm_inspect_file(host, file, action)) + if (nlm_inspect_file(host, file, match)) ret = 1; mutex_lock(&nlm_file_mutex); @@ -277,14 +287,46 @@ nlm_release_file(struct nlm_file *file) mutex_lock(&nlm_file_mutex); /* If there are no more locks etc, delete the file */ - if(--file->f_count == 0) { - if(!nlm_inspect_file(NULL, file, NLM_ACT_CHECK)) - nlm_delete_file(file); - } + if (--file->f_count == 0 && !nlm_file_inuse(file)) + nlm_delete_file(file); mutex_unlock(&nlm_file_mutex); } +/* + * Helpers function for resource traversal + * + * nlmsvc_mark_host: + * used by the garbage collector; simply sets h_inuse. + * Always returns 0. + * + * nlmsvc_same_host: + * returns 1 iff the two hosts match. Used to release + * all resources bound to a specific host. + * + * nlmsvc_is_client: + * returns 1 iff the host is a client. + * Used by nlmsvc_invalidate_all + */ +static int +nlmsvc_mark_host(struct nlm_host *host, struct nlm_host *dummy) +{ + host->h_inuse = 1; + return 0; +} + +static int +nlmsvc_same_host(struct nlm_host *host, struct nlm_host *other) +{ + return host == other; +} + +static int +nlmsvc_is_client(struct nlm_host *host, struct nlm_host *dummy) +{ + return host->h_server; +} + /* * Mark all hosts that still hold resources */ @@ -292,8 +334,7 @@ void nlmsvc_mark_resources(void) { dprintk("lockd: nlmsvc_mark_resources\n"); - - nlm_traverse_files(NULL, NLM_ACT_MARK); + nlm_traverse_files(NULL, nlmsvc_mark_host); } /* @@ -304,7 +345,7 @@ nlmsvc_free_host_resources(struct nlm_host *host) { dprintk("lockd: nlmsvc_free_host_resources\n"); - if (nlm_traverse_files(host, NLM_ACT_UNLOCK)) { + if (nlm_traverse_files(host, nlmsvc_same_host)) { printk(KERN_WARNING "lockd: couldn't remove all locks held by %s\n", host->h_name); @@ -319,8 +360,16 @@ void nlmsvc_invalidate_all(void) { struct nlm_host *host; + + /* Release all locks held by NFS clients. + * Previously, the code would call + * nlmsvc_free_host_resources for each client in + * 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); + while ((host = nlm_find_client()) != NULL) { - nlmsvc_free_host_resources(host); host->h_expires = 0; host->h_killed = 1; nlm_release_host(host); diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h index 777a91e1ac8..8c1145669d0 100644 --- a/include/linux/lockd/lockd.h +++ b/include/linux/lockd/lockd.h @@ -133,13 +133,6 @@ struct nlm_block { struct nlm_file * b_file; /* file in question */ }; -/* - * Valid actions for nlmsvc_traverse_files - */ -#define NLM_ACT_CHECK 0 /* check for locks */ -#define NLM_ACT_MARK 1 /* mark & sweep */ -#define NLM_ACT_UNLOCK 2 /* release all locks */ - /* * Global variables */ @@ -182,6 +175,12 @@ struct nsm_handle *nsm_find(const struct sockaddr_in *, const char *, int); void nsm_release(struct nsm_handle *); +/* + * This is used in garbage collection and resource reclaim + * A return value != 0 means destroy the lock/block/share + */ +typedef int (*nlm_host_match_fn_t)(struct nlm_host *cur, struct nlm_host *ref); + /* * Server-side lock handling */ @@ -193,7 +192,7 @@ u32 nlmsvc_testlock(struct nlm_file *, struct nlm_lock *, u32 nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *); unsigned long nlmsvc_retry_blocked(void); void nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *, - int action); + nlm_host_match_fn_t match); void nlmsvc_grant_reply(struct svc_rqst *, struct nlm_cookie *, u32); /* diff --git a/include/linux/lockd/share.h b/include/linux/lockd/share.h index c75a424ebe4..cd7816e74c0 100644 --- a/include/linux/lockd/share.h +++ b/include/linux/lockd/share.h @@ -25,6 +25,7 @@ u32 nlmsvc_share_file(struct nlm_host *, struct nlm_file *, struct nlm_args *); u32 nlmsvc_unshare_file(struct nlm_host *, struct nlm_file *, struct nlm_args *); -void nlmsvc_traverse_shares(struct nlm_host *, struct nlm_file *, int); +void nlmsvc_traverse_shares(struct nlm_host *, struct nlm_file *, + nlm_host_match_fn_t); #endif /* LINUX_LOCKD_SHARE_H */ -- 2.41.1