Commit f2af793d authored by Olaf Kirch's avatar Olaf Kirch Committed by Linus Torvalds

[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: default avatarOlaf Kirch <okir@suse.de>
Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 07ba8063
...@@ -265,24 +265,20 @@ static void nlmsvc_release_block(struct nlm_block *block) ...@@ -265,24 +265,20 @@ static void nlmsvc_release_block(struct nlm_block *block)
kref_put(&block->b_count, nlmsvc_free_block); kref_put(&block->b_count, nlmsvc_free_block);
} }
static void nlmsvc_act_mark(struct nlm_host *host, struct nlm_file *file) /*
{ * Loop over all blocks and delete blocks held by
struct nlm_block *block; * a matching host.
*/
down(&file->f_sema); void nlmsvc_traverse_blocks(struct nlm_host *host,
list_for_each_entry(block, &file->f_blocks, b_flist) struct nlm_file *file,
block->b_host->h_inuse = 1; nlm_host_match_fn_t match)
up(&file->f_sema);
}
static void nlmsvc_act_unlock(struct nlm_host *host, struct nlm_file *file)
{ {
struct nlm_block *block, *next; struct nlm_block *block, *next;
restart: restart:
down(&file->f_sema); down(&file->f_sema);
list_for_each_entry_safe(block, next, &file->f_blocks, b_flist) { 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; continue;
/* Do not destroy blocks that are not on /* Do not destroy blocks that are not on
* the global retry list - why? */ * the global retry list - why? */
...@@ -297,19 +293,6 @@ restart: ...@@ -297,19 +293,6 @@ restart:
up(&file->f_sema); 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 * Initialize arguments for GRANTED call. The nlm_rqst structure
* has been cleared already. * has been cleared already.
......
...@@ -85,25 +85,21 @@ nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file, ...@@ -85,25 +85,21 @@ nlmsvc_unshare_file(struct nlm_host *host, struct nlm_file *file,
} }
/* /*
* Traverse all shares for a given file (and host). * Traverse all shares for a given file, and delete
* NLM_ACT_CHECK is handled by nlmsvc_inspect_file. * those owned by the given (type of) host
*/ */
void void nlmsvc_traverse_shares(struct nlm_host *host, struct nlm_file *file,
nlmsvc_traverse_shares(struct nlm_host *host, struct nlm_file *file, int action) nlm_host_match_fn_t match)
{ {
struct nlm_share *share, **shpp; struct nlm_share *share, **shpp;
shpp = &file->f_shares; shpp = &file->f_shares;
while ((share = *shpp) != NULL) { while ((share = *shpp) != NULL) {
if (action == NLM_ACT_MARK) if (match(share->s_host, host)) {
share->s_host->h_inuse = 1;
else if (action == NLM_ACT_UNLOCK) {
if (host == NULL || host == share->s_host) {
*shpp = share->s_next; *shpp = share->s_next;
kfree(share); kfree(share);
continue; continue;
} }
}
shpp = &share->s_next; shpp = &share->s_next;
} }
} }
...@@ -165,7 +165,8 @@ nlm_delete_file(struct nlm_file *file) ...@@ -165,7 +165,8 @@ nlm_delete_file(struct nlm_file *file)
* action. * action.
*/ */
static int 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 inode *inode = nlmsvc_file_inode(file);
struct file_lock *fl; struct file_lock *fl;
...@@ -179,17 +180,11 @@ again: ...@@ -179,17 +180,11 @@ again:
/* update current lock count */ /* update current lock count */
file->f_locks++; file->f_locks++;
lockhost = (struct nlm_host *) fl->fl_owner; lockhost = (struct nlm_host *) fl->fl_owner;
if (action == NLM_ACT_MARK) if (match(lockhost, host)) {
lockhost->h_inuse = 1;
else if (action == NLM_ACT_CHECK)
return 1;
else if (action == NLM_ACT_UNLOCK) {
struct file_lock lock = *fl; struct file_lock lock = *fl;
if (host && lockhost != host)
continue;
lock.fl_type = F_UNLCK; lock.fl_type = F_UNLCK;
lock.fl_start = 0; lock.fl_start = 0;
lock.fl_end = OFFSET_MAX; lock.fl_end = OFFSET_MAX;
...@@ -206,27 +201,42 @@ again: ...@@ -206,27 +201,42 @@ again:
} }
/* /*
* Operate on a single file * Inspect a single file
*/ */
static inline int static inline int
nlm_inspect_file(struct nlm_host *host, struct nlm_file *file, int action) nlm_inspect_file(struct nlm_host *host, struct nlm_file *file, nlm_host_match_fn_t match)
{ {
if (action == NLM_ACT_CHECK) { nlmsvc_traverse_blocks(host, file, match);
/* Fast path for mark and sweep garbage collection */ nlmsvc_traverse_shares(host, file, match);
if (file->f_count || list_empty(&file->f_blocks) || file->f_shares) 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_file_inuse(struct nlm_file *file)
{
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; 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. * Loop over all files in the file table.
*/ */
static int 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 hlist_node *pos, *next;
struct nlm_file *file; struct nlm_file *file;
...@@ -240,7 +250,7 @@ nlm_traverse_files(struct nlm_host *host, int action) ...@@ -240,7 +250,7 @@ nlm_traverse_files(struct nlm_host *host, int action)
/* Traverse locks, blocks and shares of this file /* Traverse locks, blocks and shares of this file
* and update file->f_locks count */ * and update file->f_locks count */
if (nlm_inspect_file(host, file, action)) if (nlm_inspect_file(host, file, match))
ret = 1; ret = 1;
mutex_lock(&nlm_file_mutex); mutex_lock(&nlm_file_mutex);
...@@ -277,14 +287,46 @@ nlm_release_file(struct nlm_file *file) ...@@ -277,14 +287,46 @@ nlm_release_file(struct nlm_file *file)
mutex_lock(&nlm_file_mutex); mutex_lock(&nlm_file_mutex);
/* If there are no more locks etc, delete the file */ /* If there are no more locks etc, delete the file */
if(--file->f_count == 0) { if (--file->f_count == 0 && !nlm_file_inuse(file))
if(!nlm_inspect_file(NULL, file, NLM_ACT_CHECK))
nlm_delete_file(file); nlm_delete_file(file);
}
mutex_unlock(&nlm_file_mutex); 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 * Mark all hosts that still hold resources
*/ */
...@@ -292,8 +334,7 @@ void ...@@ -292,8 +334,7 @@ void
nlmsvc_mark_resources(void) nlmsvc_mark_resources(void)
{ {
dprintk("lockd: nlmsvc_mark_resources\n"); dprintk("lockd: nlmsvc_mark_resources\n");
nlm_traverse_files(NULL, nlmsvc_mark_host);
nlm_traverse_files(NULL, NLM_ACT_MARK);
} }
/* /*
...@@ -304,7 +345,7 @@ nlmsvc_free_host_resources(struct nlm_host *host) ...@@ -304,7 +345,7 @@ nlmsvc_free_host_resources(struct nlm_host *host)
{ {
dprintk("lockd: nlmsvc_free_host_resources\n"); 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 printk(KERN_WARNING
"lockd: couldn't remove all locks held by %s\n", "lockd: couldn't remove all locks held by %s\n",
host->h_name); host->h_name);
...@@ -319,8 +360,16 @@ void ...@@ -319,8 +360,16 @@ void
nlmsvc_invalidate_all(void) nlmsvc_invalidate_all(void)
{ {
struct nlm_host *host; 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) { while ((host = nlm_find_client()) != NULL) {
nlmsvc_free_host_resources(host);
host->h_expires = 0; host->h_expires = 0;
host->h_killed = 1; host->h_killed = 1;
nlm_release_host(host); nlm_release_host(host);
......
...@@ -133,13 +133,6 @@ struct nlm_block { ...@@ -133,13 +133,6 @@ struct nlm_block {
struct nlm_file * b_file; /* file in question */ 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 * Global variables
*/ */
...@@ -182,6 +175,12 @@ struct nsm_handle *nsm_find(const struct sockaddr_in *, const char *, int); ...@@ -182,6 +175,12 @@ struct nsm_handle *nsm_find(const struct sockaddr_in *, const char *, int);
void nsm_release(struct nsm_handle *); 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 * Server-side lock handling
*/ */
...@@ -193,7 +192,7 @@ u32 nlmsvc_testlock(struct nlm_file *, struct nlm_lock *, ...@@ -193,7 +192,7 @@ u32 nlmsvc_testlock(struct nlm_file *, struct nlm_lock *,
u32 nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *); u32 nlmsvc_cancel_blocked(struct nlm_file *, struct nlm_lock *);
unsigned long nlmsvc_retry_blocked(void); unsigned long nlmsvc_retry_blocked(void);
void nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *, 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); void nlmsvc_grant_reply(struct svc_rqst *, struct nlm_cookie *, u32);
/* /*
......
...@@ -25,6 +25,7 @@ u32 nlmsvc_share_file(struct nlm_host *, struct nlm_file *, ...@@ -25,6 +25,7 @@ u32 nlmsvc_share_file(struct nlm_host *, struct nlm_file *,
struct nlm_args *); struct nlm_args *);
u32 nlmsvc_unshare_file(struct nlm_host *, struct nlm_file *, u32 nlmsvc_unshare_file(struct nlm_host *, struct nlm_file *,
struct nlm_args *); 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 */ #endif /* LINUX_LOCKD_SHARE_H */
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment