1 files changed, 70 insertions, 274 deletions

diff --git a/fs/afs/cell.c b/fs/afs/cell.c
index 28ed84ec8ff7..733c60246ab0 100644
--- a/fs/afs/cell.c
+++ b/fs/afs/cell.c
@@ -11,15 +11,6 @@
 
 #include <linux/module.h>
 #include <linux/slab.h>
-#include <rxrpc/peer.h>
-#include <rxrpc/connection.h>
-#include "volume.h"
-#include "cell.h"
-#include "server.h"
-#include "transport.h"
-#include "vlclient.h"
-#include "kafstimod.h"
-#include "super.h"
 #include "internal.h"
 
 DECLARE_RWSEM(afs_proc_cells_sem);
@@ -28,34 +19,21 @@ LIST_HEAD(afs_proc_cells);
 static struct list_head afs_cells = LIST_HEAD_INIT(afs_cells);
 static DEFINE_RWLOCK(afs_cells_lock);
 static DECLARE_RWSEM(afs_cells_sem); /* add/remove serialisation */
+static DECLARE_WAIT_QUEUE_HEAD(afs_cells_freeable_wq);
 static struct afs_cell *afs_cell_root;
 
-#ifdef AFS_CACHING_SUPPORT
-static cachefs_match_val_t afs_cell_cache_match(void *target,
-						const void *entry);
-static void afs_cell_cache_update(void *source, void *entry);
-
-struct cachefs_index_def afs_cache_cell_index_def = {
-	.name			= "cell_ix",
-	.data_size		= sizeof(struct afs_cache_cell),
-	.keys[0]		= { CACHEFS_INDEX_KEYS_ASCIIZ, 64 },
-	.match			= afs_cell_cache_match,
-	.update			= afs_cell_cache_update,
-};
-#endif
-
 /*
  * create a cell record
  * - "name" is the name of the cell
  * - "vllist" is a colon separated list of IP addresses in "a.b.c.d" format
  */
-int afs_cell_create(const char *name, char *vllist, struct afs_cell **_cell)
+struct afs_cell *afs_cell_create(const char *name, char *vllist)
 {
 	struct afs_cell *cell;
 	char *next;
 	int ret;
 
-	_enter("%s", name);
+	_enter("%s,%s", name, vllist);
 
 	BUG_ON(!name); /* TODO: want to look up "this cell" in the cache */
 
@@ -63,27 +41,24 @@ int afs_cell_create(const char *name, char *vllist, struct afs_cell **_cell)
 	cell = kmalloc(sizeof(struct afs_cell) + strlen(name) + 1, GFP_KERNEL);
 	if (!cell) {
 		_leave(" = -ENOMEM");
-		return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 	}
 
 	down_write(&afs_cells_sem);
 
 	memset(cell, 0, sizeof(struct afs_cell));
-	atomic_set(&cell->usage, 0);
+	atomic_set(&cell->usage, 1);
 
 	INIT_LIST_HEAD(&cell->link);
 
-	rwlock_init(&cell->sv_lock);
-	INIT_LIST_HEAD(&cell->sv_list);
-	INIT_LIST_HEAD(&cell->sv_graveyard);
-	spin_lock_init(&cell->sv_gylock);
+	rwlock_init(&cell->servers_lock);
+	INIT_LIST_HEAD(&cell->servers);
 
 	init_rwsem(&cell->vl_sem);
 	INIT_LIST_HEAD(&cell->vl_list);
-	INIT_LIST_HEAD(&cell->vl_graveyard);
-	spin_lock_init(&cell->vl_gylock);
+	spin_lock_init(&cell->vl_lock);
 
-	strcpy(cell->name,name);
+	strcpy(cell->name, name);
 
 	/* fill in the VL server list from the rest of the string */
 	ret = -EINVAL;
@@ -106,9 +81,9 @@ int afs_cell_create(const char *name, char *vllist, struct afs_cell **_cell)
 		if (cell->vl_naddrs >= AFS_CELL_MAX_ADDRS)
 			break;
 
-	} while(vllist = next, vllist);
+	} while ((vllist = next));
 
-	/* add a proc dir for this cell */
+	/* add a proc directory for this cell */
 	ret = afs_proc_cell_setup(cell);
 	if (ret < 0)
 		goto error;
@@ -129,30 +104,29 @@ int afs_cell_create(const char *name, char *vllist, struct afs_cell **_cell)
 	down_write(&afs_proc_cells_sem);
 	list_add_tail(&cell->proc_link, &afs_proc_cells);
 	up_write(&afs_proc_cells_sem);
-
-	*_cell = cell;
 	up_write(&afs_cells_sem);
 
-	_leave(" = 0 (%p)", cell);
-	return 0;
+	_leave(" = %p", cell);
+	return cell;
 
 badaddr:
-	printk(KERN_ERR "kAFS: bad VL server IP address: '%s'\n", vllist);
+	printk(KERN_ERR "kAFS: bad VL server IP address\n");
 error:
 	up_write(&afs_cells_sem);
 	kfree(cell);
 	_leave(" = %d", ret);
-	return ret;
+	return ERR_PTR(ret);
 }
 
 /*
- * initialise the cell database from module parameters
+ * set the root cell information
+ * - can be called with a module parameter string
+ * - can be called from a write to /proc/fs/afs/rootcell
  */
 int afs_cell_init(char *rootcell)
 {
 	struct afs_cell *old_root, *new_root;
 	char *cp;
-	int ret;
 
 	_enter("");
 
@@ -160,79 +134,60 @@ int afs_cell_init(char *rootcell)
 		/* module is loaded with no parameters, or built statically.
 		 * - in the future we might initialize cell DB here.
 		 */
-		_leave(" = 0 (but no root)");
+		_leave(" = 0 [no root]");
 		return 0;
 	}
 
 	cp = strchr(rootcell, ':');
 	if (!cp) {
 		printk(KERN_ERR "kAFS: no VL server IP addresses specified\n");
-		_leave(" = %d (no colon)", -EINVAL);
+		_leave(" = -EINVAL");
 		return -EINVAL;
 	}
 
 	/* allocate a cell record for the root cell */
 	*cp++ = 0;
-	ret = afs_cell_create(rootcell, cp, &new_root);
-	if (ret < 0) {
-		_leave(" = %d", ret);
-		return ret;
+	new_root = afs_cell_create(rootcell, cp);
+	if (IS_ERR(new_root)) {
+		_leave(" = %ld", PTR_ERR(new_root));
+		return PTR_ERR(new_root);
 	}
 
-	/* as afs_put_cell() takes locks by itself, we have to do
-	 * a little gymnastics to be race-free.
-	 */
-	afs_get_cell(new_root);
-
+	/* install the new cell */
 	write_lock(&afs_cells_lock);
-	while (afs_cell_root) {
-		old_root = afs_cell_root;
-		afs_cell_root = NULL;
-		write_unlock(&afs_cells_lock);
-		afs_put_cell(old_root);
-		write_lock(&afs_cells_lock);
-	}
+	old_root = afs_cell_root;
 	afs_cell_root = new_root;
 	write_unlock(&afs_cells_lock);
+	afs_put_cell(old_root);
 
-	_leave(" = %d", ret);
-	return ret;
+	_leave(" = 0");
+	return 0;
 }
 
 /*
  * lookup a cell record
  */
-int afs_cell_lookup(const char *name, unsigned namesz, struct afs_cell **_cell)
+struct afs_cell *afs_cell_lookup(const char *name, unsigned namesz)
 {
 	struct afs_cell *cell;
-	int ret;
 
 	_enter("\"%*.*s\",", namesz, namesz, name ? name : "");
 
-	*_cell = NULL;
+	down_read(&afs_cells_sem);
+	read_lock(&afs_cells_lock);
 
 	if (name) {
 		/* if the cell was named, look for it in the cell record list */
-		ret = -ENOENT;
-		cell = NULL;
-		read_lock(&afs_cells_lock);
-
 		list_for_each_entry(cell, &afs_cells, link) {
 			if (strncmp(cell->name, name, namesz) == 0) {
 				afs_get_cell(cell);
 				goto found;
 			}
 		}
-		cell = NULL;
+		cell = ERR_PTR(-ENOENT);
 	found:
-
-		read_unlock(&afs_cells_lock);
-
-		if (cell)
-			ret = 0;
+		;
 	} else {
-		read_lock(&afs_cells_lock);
-
 		cell = afs_cell_root;
 		if (!cell) {
 			/* this should not happen unless user tries to mount
@@ -241,37 +196,32 @@ int afs_cell_lookup(const char *name, unsigned namesz, struct afs_cell **_cell)
 			 * ENOENT might be "more appropriate" but they happen
 			 * for other reasons.
 			 */
-			ret = -EDESTADDRREQ;
+			cell = ERR_PTR(-EDESTADDRREQ);
 		} else {
 			afs_get_cell(cell);
-			ret = 0;
 		}
 
-		read_unlock(&afs_cells_lock);
 	}
 
-	*_cell = cell;
-	_leave(" = %d (%p)", ret, cell);
-	return ret;
+	read_unlock(&afs_cells_lock);
+	up_read(&afs_cells_sem);
+	_leave(" = %p", cell);
+	return cell;
 }
 
 /*
  * try and get a cell record
  */
-struct afs_cell *afs_get_cell_maybe(struct afs_cell **_cell)
+struct afs_cell *afs_get_cell_maybe(struct afs_cell *cell)
 {
-	struct afs_cell *cell;
-
 	write_lock(&afs_cells_lock);
 
-	cell = *_cell;
 	if (cell && !list_empty(&cell->link))
 		afs_get_cell(cell);
 	else
 		cell = NULL;
 
 	write_unlock(&afs_cells_lock);
-
 	return cell;
 }
 
@@ -285,8 +235,7 @@ void afs_put_cell(struct afs_cell *cell)
 
 	_enter("%p{%d,%s}", cell, atomic_read(&cell->usage), cell->name);
 
-	/* sanity check */
-	BUG_ON(atomic_read(&cell->usage) <= 0);
+	ASSERTCMP(atomic_read(&cell->usage), >, 0);
 
 	/* to prevent a race, the decrement and the dequeue must be effectively
 	 * atomic */
@@ -298,35 +247,49 @@ void afs_put_cell(struct afs_cell *cell)
 		return;
 	}
 
+	ASSERT(list_empty(&cell->servers));
+	ASSERT(list_empty(&cell->vl_list));
+
 	write_unlock(&afs_cells_lock);
 
-	BUG_ON(!list_empty(&cell->sv_list));
-	BUG_ON(!list_empty(&cell->sv_graveyard));
-	BUG_ON(!list_empty(&cell->vl_list));
-	BUG_ON(!list_empty(&cell->vl_graveyard));
+	wake_up(&afs_cells_freeable_wq);
 
 	_leave(" [unused]");
 }
 
 /*
  * destroy a cell record
+ * - must be called with the afs_cells_sem write-locked
+ * - cell->link should have been broken by the caller
  */
 static void afs_cell_destroy(struct afs_cell *cell)
 {
 	_enter("%p{%d,%s}", cell, atomic_read(&cell->usage), cell->name);
 
-	/* to prevent a race, the decrement and the dequeue must be effectively
-	 * atomic */
-	write_lock(&afs_cells_lock);
+	ASSERTCMP(atomic_read(&cell->usage), >=, 0);
+	ASSERT(list_empty(&cell->link));
 
-	/* sanity check */
-	BUG_ON(atomic_read(&cell->usage) != 0);
+	/* wait for everyone to stop using the cell */
+	if (atomic_read(&cell->usage) > 0) {
+		DECLARE_WAITQUEUE(myself, current);
 
-	list_del_init(&cell->link);
+		_debug("wait for cell %s", cell->name);
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		add_wait_queue(&afs_cells_freeable_wq, &myself);
 
-	write_unlock(&afs_cells_lock);
+		while (atomic_read(&cell->usage) > 0) {
+			schedule();
+			set_current_state(TASK_UNINTERRUPTIBLE);
+		}
 
-	down_write(&afs_cells_sem);
+		remove_wait_queue(&afs_cells_freeable_wq, &myself);
+		set_current_state(TASK_RUNNING);
+	}
+
+	_debug("cell dead");
+	ASSERTCMP(atomic_read(&cell->usage), ==, 0);
+	ASSERT(list_empty(&cell->servers));
+	ASSERT(list_empty(&cell->vl_list));
 
 	afs_proc_cell_remove(cell);
 
@@ -338,101 +301,25 @@ static void afs_cell_destroy(struct afs_cell *cell)
 	cachefs_relinquish_cookie(cell->cache, 0);
 #endif
 
-	up_write(&afs_cells_sem);
-
-	BUG_ON(!list_empty(&cell->sv_list));
-	BUG_ON(!list_empty(&cell->sv_graveyard));
-	BUG_ON(!list_empty(&cell->vl_list));
-	BUG_ON(!list_empty(&cell->vl_graveyard));
-
-	/* finish cleaning up the cell */
 	kfree(cell);
 
 	_leave(" [destroyed]");
 }
 
 /*
- * lookup the server record corresponding to an Rx RPC peer
- */
-int afs_server_find_by_peer(const struct rxrpc_peer *peer,
-			    struct afs_server **_server)
-{
-	struct afs_server *server;
-	struct afs_cell *cell;
-
-	_enter("%p{a=%08x},", peer, ntohl(peer->addr.s_addr));
-
-	/* search the cell list */
-	read_lock(&afs_cells_lock);
-
-	list_for_each_entry(cell, &afs_cells, link) {
-
-		_debug("? cell %s",cell->name);
-
-		write_lock(&cell->sv_lock);
-
-		/* check the active list */
-		list_for_each_entry(server, &cell->sv_list, link) {
-			_debug("?? server %08x", ntohl(server->addr.s_addr));
-
-			if (memcmp(&server->addr, &peer->addr,
-				   sizeof(struct in_addr)) == 0)
-				goto found_server;
-		}
-
-		/* check the inactive list */
-		spin_lock(&cell->sv_gylock);
-		list_for_each_entry(server, &cell->sv_graveyard, link) {
-			_debug("?? dead server %08x",
-			       ntohl(server->addr.s_addr));
-
-			if (memcmp(&server->addr, &peer->addr,
-				   sizeof(struct in_addr)) == 0)
-				goto found_dead_server;
-		}
-		spin_unlock(&cell->sv_gylock);
-
-		write_unlock(&cell->sv_lock);
-	}
-	read_unlock(&afs_cells_lock);
-
-	_leave(" = -ENOENT");
-	return -ENOENT;
-
-	/* we found it in the graveyard - resurrect it */
-found_dead_server:
-	list_move_tail(&server->link, &cell->sv_list);
-	afs_get_server(server);
-	afs_kafstimod_del_timer(&server->timeout);
-	spin_unlock(&cell->sv_gylock);
-	goto success;
-
-	/* we found it - increment its ref count and return it */
-found_server:
-	afs_get_server(server);
-
-success:
-	write_unlock(&cell->sv_lock);
-	read_unlock(&afs_cells_lock);
-
-	*_server = server;
-	_leave(" = 0 (s=%p c=%p)", server, cell);
-	return 0;
-}
-
-/*
  * purge in-memory cell database on module unload or afs_init() failure
  * - the timeout daemon is stopped before calling this
  */
 void afs_cell_purge(void)
 {
-	struct afs_vlocation *vlocation;
 	struct afs_cell *cell;
 
 	_enter("");
 
 	afs_put_cell(afs_cell_root);
 
+	down_write(&afs_cells_sem);
+
 	while (!list_empty(&afs_cells)) {
 		cell = NULL;
 
@@ -451,102 +338,11 @@ void afs_cell_purge(void)
 			_debug("PURGING CELL %s (%d)",
 			       cell->name, atomic_read(&cell->usage));
 
-			BUG_ON(!list_empty(&cell->sv_list));
-			BUG_ON(!list_empty(&cell->vl_list));
-
-			/* purge the cell's VL graveyard list */
-			_debug(" - clearing VL graveyard");
-
-			spin_lock(&cell->vl_gylock);
-
-			while (!list_empty(&cell->vl_graveyard)) {
-				vlocation = list_entry(cell->vl_graveyard.next,
-						       struct afs_vlocation,
-						       link);
-				list_del_init(&vlocation->link);
-
-				afs_kafstimod_del_timer(&vlocation->timeout);
-
-				spin_unlock(&cell->vl_gylock);
-
-				afs_vlocation_do_timeout(vlocation);
-				/* TODO: race if move to use krxtimod instead
-				 * of kafstimod */
-
-				spin_lock(&cell->vl_gylock);
-			}
-
-			spin_unlock(&cell->vl_gylock);
-
-			/* purge the cell's server graveyard list */
-			_debug(" - clearing server graveyard");
-
-			spin_lock(&cell->sv_gylock);
-
-			while (!list_empty(&cell->sv_graveyard)) {
-				struct afs_server *server;
-
-				server = list_entry(cell->sv_graveyard.next,
-						    struct afs_server, link);
-				list_del_init(&server->link);
-
-				afs_kafstimod_del_timer(&server->timeout);
-
-				spin_unlock(&cell->sv_gylock);
-
-				afs_server_do_timeout(server);
-
-				spin_lock(&cell->sv_gylock);
-			}
-
-			spin_unlock(&cell->sv_gylock);
-
 			/* now the cell should be left with no references */
 			afs_cell_destroy(cell);
 		}
 	}
 
+	up_write(&afs_cells_sem);
 	_leave("");
 }
-
-/*
- * match a cell record obtained from the cache
- */
-#ifdef AFS_CACHING_SUPPORT
-static cachefs_match_val_t afs_cell_cache_match(void *target,
-						const void *entry)
-{
-	const struct afs_cache_cell *ccell = entry;
-	struct afs_cell *cell = target;
-
-	_enter("{%s},{%s}", ccell->name, cell->name);
-
-	if (strncmp(ccell->name, cell->name, sizeof(ccell->name)) == 0) {
-		_leave(" = SUCCESS");
-		return CACHEFS_MATCH_SUCCESS;
-	}
-
-	_leave(" = FAILED");
-	return CACHEFS_MATCH_FAILED;
-}
-#endif
-
-/*
- * update a cell record in the cache
- */
-#ifdef AFS_CACHING_SUPPORT
-static void afs_cell_cache_update(void *source, void *entry)
-{
-	struct afs_cache_cell *ccell = entry;
-	struct afs_cell *cell = source;
-
-	_enter("%p,%p", source, entry);
-
-	strncpy(ccell->name, cell->name, sizeof(ccell->name));
-
-	memcpy(ccell->vl_servers,
-	       cell->vl_addrs,
-	       min(sizeof(ccell->vl_servers), sizeof(cell->vl_addrs)));
-
-}
-#endif