-/* cell.c: AFS cell and server record management
+/* AFS cell and server record management
*
* Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#include <linux/module.h>
-#include <linux/sched.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 <linux/key.h>
+#include <linux/ctype.h>
+#include <linux/sched.h>
+#include <keys/rxrpc-type.h>
#include "internal.h"
DECLARE_RWSEM(afs_proc_cells_sem);
LIST_HEAD(afs_proc_cells);
-static struct list_head afs_cells = LIST_HEAD_INIT(afs_cells);
+static LIST_HEAD(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
+ * allocate a cell record and fill in its name, VL server address list and
+ * allocate an anonymous key
*/
-int afs_cell_create(const char *name, char *vllist, struct afs_cell **_cell)
+static struct afs_cell *afs_cell_alloc(const char *name, char *vllist)
{
struct afs_cell *cell;
- char *next;
+ struct key *key;
+ size_t namelen;
+ char keyname[4 + AFS_MAXCELLNAME + 1], *cp, *dp, *next;
int ret;
- _enter("%s", name);
+ _enter("%s,%s", name, vllist);
BUG_ON(!name); /* TODO: want to look up "this cell" in the cache */
+ namelen = strlen(name);
+ if (namelen > AFS_MAXCELLNAME)
+ return ERR_PTR(-ENAMETOOLONG);
+
/* allocate and initialise a cell record */
- cell = kmalloc(sizeof(struct afs_cell) + strlen(name) + 1, GFP_KERNEL);
+ cell = kzalloc(sizeof(struct afs_cell) + namelen + 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);
+ memcpy(cell->name, name, namelen);
+ cell->name[namelen] = 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);
-
- strcpy(cell->name,name);
+ spin_lock_init(&cell->vl_lock);
/* fill in the VL server list from the rest of the string */
- ret = -EINVAL;
do {
unsigned a, b, c, d;
*next++ = 0;
if (sscanf(vllist, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
- goto badaddr;
+ goto bad_address;
if (a > 255 || b > 255 || c > 255 || d > 255)
- goto badaddr;
+ goto bad_address;
cell->vl_addrs[cell->vl_naddrs++].s_addr =
htonl((a << 24) | (b << 16) | (c << 8) | d);
- if (cell->vl_naddrs >= AFS_CELL_MAX_ADDRS)
- break;
+ } while (cell->vl_naddrs < AFS_CELL_MAX_ADDRS && (vllist = next));
+
+ /* create a key to represent an anonymous user */
+ memcpy(keyname, "afs@", 4);
+ dp = keyname + 4;
+ cp = cell->name;
+ do {
+ *dp++ = toupper(*cp);
+ } while (*cp++);
+
+ key = rxrpc_get_null_key(keyname);
+ if (IS_ERR(key)) {
+ _debug("no key");
+ ret = PTR_ERR(key);
+ goto error;
+ }
+ cell->anonymous_key = key;
+
+ _debug("anon key %p{%x}",
+ cell->anonymous_key, key_serial(cell->anonymous_key));
+
+ _leave(" = %p", cell);
+ return cell;
+
+bad_address:
+ printk(KERN_ERR "kAFS: bad VL server IP address\n");
+ ret = -EINVAL;
+error:
+ key_put(cell->anonymous_key);
+ kfree(cell);
+ _leave(" = %d", ret);
+ return ERR_PTR(ret);
+}
+
+/*
+ * 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
+ */
+struct afs_cell *afs_cell_create(const char *name, char *vllist)
+{
+ struct afs_cell *cell;
+ int ret;
+
+ _enter("%s,%s", name, vllist);
+
+ down_write(&afs_cells_sem);
+ read_lock(&afs_cells_lock);
+ list_for_each_entry(cell, &afs_cells, link) {
+ if (strcasecmp(cell->name, name) == 0)
+ goto duplicate_name;
+ }
+ read_unlock(&afs_cells_lock);
- } while(vllist = next, vllist);
+ cell = afs_cell_alloc(name, vllist);
+ if (IS_ERR(cell)) {
+ _leave(" = %ld", PTR_ERR(cell));
+ up_write(&afs_cells_sem);
+ return cell;
+ }
- /* 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;
-#ifdef AFS_CACHING_SUPPORT
- /* put it up for caching */
- cachefs_acquire_cookie(afs_cache_netfs.primary_index,
- &afs_vlocation_cache_index_def,
- cell,
- &cell->cache);
+#ifdef CONFIG_AFS_FSCACHE
+ /* put it up for caching (this never returns an error) */
+ cell->cache = fscache_acquire_cookie(afs_cache_netfs.primary_index,
+ &afs_cell_cache_index_def,
+ cell);
#endif
/* add to the cell lists */
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);
- error:
+error:
up_write(&afs_cells_sem);
+ key_put(cell->anonymous_key);
kfree(cell);
_leave(" = %d", ret);
- return ret;
-} /* end afs_cell_create() */
+ return ERR_PTR(ret);
+
+duplicate_name:
+ read_unlock(&afs_cells_lock);
+ up_write(&afs_cells_sem);
+ return ERR_PTR(-EEXIST);
+}
-/*****************************************************************************/
/*
- * 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("");
/* 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;
-
-} /* end afs_cell_init() */
+ _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);
-
+ ;
+ } else {
cell = afs_cell_root;
if (!cell) {
/* this should not happen unless user tries to mount
* ENOENT might be "more appropriate" but they happen
* for other reasons.
*/
- ret = -EDESTADDRREQ;
- }
- else {
+ 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;
-
-} /* end afs_cell_lookup() */
+ read_unlock(&afs_cells_lock);
+ up_read(&afs_cells_sem);
+ _leave(" = %p", cell);
+ return cell;
+}
-/*****************************************************************************/
+#if 0
/*
* 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;
-} /* end afs_get_cell_maybe() */
+}
+#endif /* 0 */
-/*****************************************************************************/
/*
* destroy a cell record
*/
_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 */
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]");
-} /* end afs_put_cell() */
+}
-/*****************************************************************************/
/*
* 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);
list_del_init(&cell->proc_link);
up_write(&afs_proc_cells_sem);
-#ifdef AFS_CACHING_SUPPORT
- cachefs_relinquish_cookie(cell->cache, 0);
+#ifdef CONFIG_AFS_FSCACHE
+ fscache_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 */
+ key_put(cell->anonymous_key);
kfree(cell);
_leave(" [destroyed]");
-} /* end afs_cell_destroy() */
+}
-/*****************************************************************************/
-/*
- * 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_del(&server->link);
- list_add_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;
-
-} /* end afs_server_find_by_peer() */
-
-/*****************************************************************************/
/*
* 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;
_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("");
-} /* end afs_cell_purge() */
-
-/*****************************************************************************/
-/*
- * 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;
-} /* end afs_cell_cache_match() */
-#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)));
-
-} /* end afs_cell_cache_update() */
-#endif
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff