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-rw-r--r--fs/afs/volume.c611
1 files changed, 312 insertions, 299 deletions
diff --git a/fs/afs/volume.c b/fs/afs/volume.c
index db73d6dad02b..684c48293353 100644
--- a/fs/afs/volume.c
+++ b/fs/afs/volume.c
@@ -10,19 +10,167 @@
*/
#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
#include <linux/slab.h>
-#include <linux/fs.h>
-#include <linux/pagemap.h>
-#include <linux/sched.h>
#include "internal.h"
-static const char *afs_voltypes[] = { "R/W", "R/O", "BAK" };
+unsigned __read_mostly afs_volume_gc_delay = 10;
+unsigned __read_mostly afs_volume_record_life = 60 * 60;
+
+static const char *const afs_voltypes[] = { "R/W", "R/O", "BAK" };
+
+/*
+ * Allocate a volume record and load it up from a vldb record.
+ */
+static struct afs_volume *afs_alloc_volume(struct afs_mount_params *params,
+ struct afs_vldb_entry *vldb,
+ unsigned long type_mask)
+{
+ struct afs_server_list *slist;
+ struct afs_server *server;
+ struct afs_volume *volume;
+ int ret = -ENOMEM, nr_servers = 0, i, j;
+
+ for (i = 0; i < vldb->nr_servers; i++)
+ if (vldb->fs_mask[i] & type_mask)
+ nr_servers++;
+
+ volume = kzalloc(sizeof(struct afs_volume), GFP_KERNEL);
+ if (!volume)
+ goto error_0;
+
+ volume->vid = vldb->vid[params->type];
+ volume->update_at = ktime_get_real_seconds() + afs_volume_record_life;
+ volume->cell = afs_get_cell(params->cell);
+ volume->type = params->type;
+ volume->type_force = params->force;
+ volume->name_len = vldb->name_len;
+
+ atomic_set(&volume->usage, 1);
+ INIT_LIST_HEAD(&volume->proc_link);
+ rwlock_init(&volume->servers_lock);
+ memcpy(volume->name, vldb->name, vldb->name_len + 1);
+
+ slist = afs_alloc_server_list(params->cell, params->key, vldb, type_mask);
+ if (IS_ERR(slist)) {
+ ret = PTR_ERR(slist);
+ goto error_1;
+ }
+
+ refcount_set(&slist->usage, 1);
+ volume->servers = slist;
+
+ /* Make sure a records exists for each server this volume occupies. */
+ for (i = 0; i < nr_servers; i++) {
+ if (!(vldb->fs_mask[i] & type_mask))
+ continue;
+
+ server = afs_lookup_server(params->cell, params->key,
+ &vldb->fs_server[i]);
+ if (IS_ERR(server)) {
+ ret = PTR_ERR(server);
+ if (ret == -ENOENT)
+ continue;
+ goto error_2;
+ }
+
+ /* Insertion-sort by server pointer */
+ for (j = 0; j < slist->nr_servers; j++)
+ if (slist->servers[j].server >= server)
+ break;
+ if (j < slist->nr_servers) {
+ if (slist->servers[j].server == server) {
+ afs_put_server(params->net, server);
+ continue;
+ }
+
+ memmove(slist->servers + j + 1,
+ slist->servers + j,
+ (slist->nr_servers - j) * sizeof(struct afs_server_entry));
+ }
+
+ slist->servers[j].server = server;
+ slist->nr_servers++;
+ }
+
+ if (slist->nr_servers == 0) {
+ ret = -EDESTADDRREQ;
+ goto error_2;
+ }
+
+ return volume;
+
+error_2:
+ afs_put_serverlist(params->net, slist);
+error_1:
+ kfree(volume);
+error_0:
+ return ERR_PTR(ret);
+}
/*
- * lookup a volume by name
- * - this can be one of the following:
+ * Look up a VLDB record for a volume.
+ */
+static struct afs_vldb_entry *afs_vl_lookup_vldb(struct afs_cell *cell,
+ struct key *key,
+ const char *volname,
+ size_t volnamesz)
+{
+ struct afs_addr_cursor ac;
+ struct afs_vldb_entry *vldb;
+ int ret;
+
+ ret = afs_set_vl_cursor(&ac, cell);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ while (afs_iterate_addresses(&ac)) {
+ if (!test_bit(ac.index, &ac.alist->probed)) {
+ ret = afs_vl_get_capabilities(cell->net, &ac, key);
+ switch (ret) {
+ case VL_SERVICE:
+ clear_bit(ac.index, &ac.alist->yfs);
+ set_bit(ac.index, &ac.alist->probed);
+ ac.addr->srx_service = ret;
+ break;
+ case YFS_VL_SERVICE:
+ set_bit(ac.index, &ac.alist->yfs);
+ set_bit(ac.index, &ac.alist->probed);
+ ac.addr->srx_service = ret;
+ break;
+ }
+ }
+
+ vldb = afs_vl_get_entry_by_name_u(cell->net, &ac, key,
+ volname, volnamesz);
+ switch (ac.error) {
+ case 0:
+ afs_end_cursor(&ac);
+ return vldb;
+ case -ECONNABORTED:
+ ac.error = afs_abort_to_error(ac.abort_code);
+ goto error;
+ case -ENOMEM:
+ case -ENONET:
+ goto error;
+ case -ENETUNREACH:
+ case -EHOSTUNREACH:
+ case -ECONNREFUSED:
+ break;
+ default:
+ ac.error = -EIO;
+ goto error;
+ }
+ }
+
+error:
+ return ERR_PTR(afs_end_cursor(&ac));
+}
+
+/*
+ * Look up a volume in the VL server and create a candidate volume record for
+ * it.
+ *
+ * The volume name can be one of the following:
* "%[cell:]volume[.]" R/W volume
* "#[cell:]volume[.]" R/O or R/W volume (rwparent=0),
* or R/W (rwparent=1) volume
@@ -42,353 +190,218 @@ static const char *afs_voltypes[] = { "R/W", "R/O", "BAK" };
* - Rule 3: If parent volume is R/W, then only mount R/W volume unless
* explicitly told otherwise
*/
-struct afs_volume *afs_volume_lookup(struct afs_mount_params *params)
+struct afs_volume *afs_create_volume(struct afs_mount_params *params)
{
- struct afs_vlocation *vlocation = NULL;
- struct afs_volume *volume = NULL;
- struct afs_server *server = NULL;
- char srvtmask;
- int ret, loop;
-
- _enter("{%*.*s,%d}",
- params->volnamesz, params->volnamesz, params->volname, params->rwpath);
-
- /* lookup the volume location record */
- vlocation = afs_vlocation_lookup(params->cell, params->key,
- params->volname, params->volnamesz);
- if (IS_ERR(vlocation)) {
- ret = PTR_ERR(vlocation);
- vlocation = NULL;
- goto error;
- }
+ struct afs_vldb_entry *vldb;
+ struct afs_volume *volume;
+ unsigned long type_mask = 1UL << params->type;
- /* make the final decision on the type we want */
- ret = -ENOMEDIUM;
- if (params->force && !(vlocation->vldb.vidmask & (1 << params->type)))
- goto error;
+ vldb = afs_vl_lookup_vldb(params->cell, params->key,
+ params->volname, params->volnamesz);
+ if (IS_ERR(vldb))
+ return ERR_CAST(vldb);
- srvtmask = 0;
- for (loop = 0; loop < vlocation->vldb.nservers; loop++)
- srvtmask |= vlocation->vldb.srvtmask[loop];
+ if (test_bit(AFS_VLDB_QUERY_ERROR, &vldb->flags)) {
+ volume = ERR_PTR(vldb->error);
+ goto error;
+ }
+ /* Make the final decision on the type we want */
+ volume = ERR_PTR(-ENOMEDIUM);
if (params->force) {
- if (!(srvtmask & (1 << params->type)))
+ if (!(vldb->flags & type_mask))
goto error;
- } else if (srvtmask & AFS_VOL_VTM_RO) {
+ } else if (test_bit(AFS_VLDB_HAS_RO, &vldb->flags)) {
params->type = AFSVL_ROVOL;
- } else if (srvtmask & AFS_VOL_VTM_RW) {
+ } else if (test_bit(AFS_VLDB_HAS_RW, &vldb->flags)) {
params->type = AFSVL_RWVOL;
} else {
goto error;
}
- down_write(&params->cell->vl_sem);
+ type_mask = 1UL << params->type;
+ volume = afs_alloc_volume(params, vldb, type_mask);
- /* is the volume already active? */
- if (vlocation->vols[params->type]) {
- /* yes - re-use it */
- volume = vlocation->vols[params->type];
- afs_get_volume(volume);
- goto success;
- }
+error:
+ kfree(vldb);
+ return volume;
+}
- /* create a new volume record */
- _debug("creating new volume record");
+/*
+ * Destroy a volume record
+ */
+static void afs_destroy_volume(struct afs_net *net, struct afs_volume *volume)
+{
+ _enter("%p", volume);
- ret = -ENOMEM;
- volume = kzalloc(sizeof(struct afs_volume), GFP_KERNEL);
- if (!volume)
- goto error_up;
+#ifdef CONFIG_AFS_FSCACHE
+ ASSERTCMP(volume->cache, ==, NULL);
+#endif
- atomic_set(&volume->usage, 1);
- volume->type = params->type;
- volume->type_force = params->force;
- volume->cell = params->cell;
- volume->vid = vlocation->vldb.vid[params->type];
-
- init_rwsem(&volume->server_sem);
-
- /* look up all the applicable server records */
- for (loop = 0; loop < 8; loop++) {
- if (vlocation->vldb.srvtmask[loop] & (1 << volume->type)) {
- server = afs_lookup_server(
- volume->cell, &vlocation->vldb.servers[loop]);
- if (IS_ERR(server)) {
- ret = PTR_ERR(server);
- goto error_discard;
- }
+ afs_put_serverlist(net, volume->servers);
+ afs_put_cell(net, volume->cell);
+ kfree(volume);
- volume->servers[volume->nservers] = server;
- volume->nservers++;
- }
+ _leave(" [destroyed]");
+}
+
+/*
+ * Drop a reference on a volume record.
+ */
+void afs_put_volume(struct afs_cell *cell, struct afs_volume *volume)
+{
+ if (volume) {
+ _enter("%s", volume->name);
+
+ if (atomic_dec_and_test(&volume->usage))
+ afs_destroy_volume(cell->net, volume);
}
+}
- /* attach the cache and volume location */
+/*
+ * Activate a volume.
+ */
+void afs_activate_volume(struct afs_volume *volume)
+{
#ifdef CONFIG_AFS_FSCACHE
- volume->cache = fscache_acquire_cookie(vlocation->cache,
+ volume->cache = fscache_acquire_cookie(volume->cell->cache,
&afs_volume_cache_index_def,
volume, true);
#endif
- afs_get_vlocation(vlocation);
- volume->vlocation = vlocation;
-
- vlocation->vols[volume->type] = volume;
-
-success:
- _debug("kAFS selected %s volume %08x",
- afs_voltypes[volume->type], volume->vid);
- up_write(&params->cell->vl_sem);
- afs_put_vlocation(vlocation);
- _leave(" = %p", volume);
- return volume;
-
- /* clean up */
-error_up:
- up_write(&params->cell->vl_sem);
-error:
- afs_put_vlocation(vlocation);
- _leave(" = %d", ret);
- return ERR_PTR(ret);
-
-error_discard:
- up_write(&params->cell->vl_sem);
-
- for (loop = volume->nservers - 1; loop >= 0; loop--)
- afs_put_server(volume->servers[loop]);
- kfree(volume);
- goto error;
+ write_lock(&volume->cell->proc_lock);
+ list_add_tail(&volume->proc_link, &volume->cell->proc_volumes);
+ write_unlock(&volume->cell->proc_lock);
}
/*
- * destroy a volume record
+ * Deactivate a volume.
*/
-void afs_put_volume(struct afs_volume *volume)
+void afs_deactivate_volume(struct afs_volume *volume)
{
- struct afs_vlocation *vlocation;
- int loop;
-
- if (!volume)
- return;
-
- _enter("%p", volume);
+ _enter("%s", volume->name);
- ASSERTCMP(atomic_read(&volume->usage), >, 0);
+ write_lock(&volume->cell->proc_lock);
+ list_del_init(&volume->proc_link);
+ write_unlock(&volume->cell->proc_lock);
- vlocation = volume->vlocation;
-
- /* to prevent a race, the decrement and the dequeue must be effectively
- * atomic */
- down_write(&vlocation->cell->vl_sem);
-
- if (likely(!atomic_dec_and_test(&volume->usage))) {
- up_write(&vlocation->cell->vl_sem);
- _leave("");
- return;
- }
-
- vlocation->vols[volume->type] = NULL;
-
- up_write(&vlocation->cell->vl_sem);
-
- /* finish cleaning up the volume */
#ifdef CONFIG_AFS_FSCACHE
- fscache_relinquish_cookie(volume->cache, 0);
+ fscache_relinquish_cookie(volume->cache,
+ test_bit(AFS_VOLUME_DELETED, &volume->flags));
+ volume->cache = NULL;
#endif
- afs_put_vlocation(vlocation);
-
- for (loop = volume->nservers - 1; loop >= 0; loop--)
- afs_put_server(volume->servers[loop]);
-
- kfree(volume);
- _leave(" [destroyed]");
+ _leave("");
}
/*
- * pick a server to use to try accessing this volume
- * - returns with an elevated usage count on the server chosen
+ * Query the VL service to update the volume status.
*/
-struct afs_server *afs_volume_pick_fileserver(struct afs_vnode *vnode)
+static int afs_update_volume_status(struct afs_volume *volume, struct key *key)
{
- struct afs_volume *volume = vnode->volume;
- struct afs_server *server;
- int ret, state, loop;
+ struct afs_server_list *new, *old, *discard;
+ struct afs_vldb_entry *vldb;
+ char idbuf[16];
+ int ret, idsz;
+
+ _enter("");
+
+ /* We look up an ID by passing it as a decimal string in the
+ * operation's name parameter.
+ */
+ idsz = sprintf(idbuf, "%u", volume->vid);
- _enter("%s", volume->vlocation->vldb.name);
+ vldb = afs_vl_lookup_vldb(volume->cell, key, idbuf, idsz);
+ if (IS_ERR(vldb)) {
+ ret = PTR_ERR(vldb);
+ goto error;
+ }
- /* stick with the server we're already using if we can */
- if (vnode->server && vnode->server->fs_state == 0) {
- afs_get_server(vnode->server);
- _leave(" = %p [current]", vnode->server);
- return vnode->server;
+ /* See if the volume got renamed. */
+ if (vldb->name_len != volume->name_len ||
+ memcmp(vldb->name, volume->name, vldb->name_len) != 0) {
+ /* TODO: Use RCU'd string. */
+ memcpy(volume->name, vldb->name, AFS_MAXVOLNAME);
+ volume->name_len = vldb->name_len;
}
- down_read(&volume->server_sem);
+ /* See if the volume's server list got updated. */
+ new = afs_alloc_server_list(volume->cell, key,
+ vldb, (1 << volume->type));
+ if (IS_ERR(new)) {
+ ret = PTR_ERR(new);
+ goto error_vldb;
+ }
- /* handle the no-server case */
- if (volume->nservers == 0) {
- ret = volume->rjservers ? -ENOMEDIUM : -ESTALE;
- up_read(&volume->server_sem);
- _leave(" = %d [no servers]", ret);
- return ERR_PTR(ret);
+ write_lock(&volume->servers_lock);
+
+ discard = new;
+ old = volume->servers;
+ if (afs_annotate_server_list(new, old)) {
+ new->seq = volume->servers_seq + 1;
+ volume->servers = new;
+ smp_wmb();
+ volume->servers_seq++;
+ discard = old;
}
- /* basically, just search the list for the first live server and use
- * that */
+ volume->update_at = ktime_get_real_seconds() + afs_volume_record_life;
+ clear_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags);
+ write_unlock(&volume->servers_lock);
ret = 0;
- for (loop = 0; loop < volume->nservers; loop++) {
- server = volume->servers[loop];
- state = server->fs_state;
- _debug("consider %d [%d]", loop, state);
+ afs_put_serverlist(volume->cell->net, discard);
+error_vldb:
+ kfree(vldb);
+error:
+ _leave(" = %d", ret);
+ return ret;
+}
- switch (state) {
- /* found an apparently healthy server */
- case 0:
- afs_get_server(server);
- up_read(&volume->server_sem);
- _leave(" = %p (picked %08x)",
- server, ntohl(server->addr.s_addr));
- return server;
+/*
+ * Make sure the volume record is up to date.
+ */
+int afs_check_volume_status(struct afs_volume *volume, struct key *key)
+{
+ time64_t now = ktime_get_real_seconds();
+ int ret, retries = 0;
- case -ENETUNREACH:
- if (ret == 0)
- ret = state;
- break;
+ _enter("");
- case -EHOSTUNREACH:
- if (ret == 0 ||
- ret == -ENETUNREACH)
- ret = state;
- break;
+ if (volume->update_at <= now)
+ set_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags);
- case -ECONNREFUSED:
- if (ret == 0 ||
- ret == -ENETUNREACH ||
- ret == -EHOSTUNREACH)
- ret = state;
- break;
+retry:
+ if (!test_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags) &&
+ !test_bit(AFS_VOLUME_WAIT, &volume->flags)) {
+ _leave(" = 0");
+ return 0;
+ }
- default:
- case -EREMOTEIO:
- if (ret == 0 ||
- ret == -ENETUNREACH ||
- ret == -EHOSTUNREACH ||
- ret == -ECONNREFUSED)
- ret = state;
- break;
- }
+ if (!test_and_set_bit_lock(AFS_VOLUME_UPDATING, &volume->flags)) {
+ ret = afs_update_volume_status(volume, key);
+ clear_bit_unlock(AFS_VOLUME_WAIT, &volume->flags);
+ clear_bit_unlock(AFS_VOLUME_UPDATING, &volume->flags);
+ wake_up_bit(&volume->flags, AFS_VOLUME_WAIT);
+ _leave(" = %d", ret);
+ return ret;
}
- /* no available servers
- * - TODO: handle the no active servers case better
- */
- up_read(&volume->server_sem);
- _leave(" = %d", ret);
- return ERR_PTR(ret);
-}
+ if (!test_bit(AFS_VOLUME_WAIT, &volume->flags)) {
+ _leave(" = 0 [no wait]");
+ return 0;
+ }
-/*
- * release a server after use
- * - releases the ref on the server struct that was acquired by picking
- * - records result of using a particular server to access a volume
- * - return 0 to try again, 1 if okay or to issue error
- * - the caller must release the server struct if result was 0
- */
-int afs_volume_release_fileserver(struct afs_vnode *vnode,
- struct afs_server *server,
- int result)
-{
- struct afs_volume *volume = vnode->volume;
- unsigned loop;
-
- _enter("%s,%08x,%d",
- volume->vlocation->vldb.name, ntohl(server->addr.s_addr),
- result);
-
- switch (result) {
- /* success */
- case 0:
- server->fs_act_jif = jiffies;
- server->fs_state = 0;
- _leave("");
- return 1;
-
- /* the fileserver denied all knowledge of the volume */
- case -ENOMEDIUM:
- server->fs_act_jif = jiffies;
- down_write(&volume->server_sem);
-
- /* firstly, find where the server is in the active list (if it
- * is) */
- for (loop = 0; loop < volume->nservers; loop++)
- if (volume->servers[loop] == server)
- goto present;
-
- /* no longer there - may have been discarded by another op */
- goto try_next_server_upw;
-
- present:
- volume->nservers--;
- memmove(&volume->servers[loop],
- &volume->servers[loop + 1],
- sizeof(volume->servers[loop]) *
- (volume->nservers - loop));
- volume->servers[volume->nservers] = NULL;
- afs_put_server(server);
- volume->rjservers++;
-
- if (volume->nservers > 0)
- /* another server might acknowledge its existence */
- goto try_next_server_upw;
-
- /* handle the case where all the fileservers have rejected the
- * volume
- * - TODO: try asking the fileservers for volume information
- * - TODO: contact the VL server again to see if the volume is
- * no longer registered
- */
- up_write(&volume->server_sem);
- afs_put_server(server);
- _leave(" [completely rejected]");
- return 1;
-
- /* problem reaching the server */
- case -ENETUNREACH:
- case -EHOSTUNREACH:
- case -ECONNREFUSED:
- case -ETIME:
- case -ETIMEDOUT:
- case -EREMOTEIO:
- /* mark the server as dead
- * TODO: vary dead timeout depending on error
- */
- spin_lock(&server->fs_lock);
- if (!server->fs_state) {
- server->fs_dead_jif = jiffies + HZ * 10;
- server->fs_state = result;
- printk("kAFS: SERVER DEAD state=%d\n", result);
- }
- spin_unlock(&server->fs_lock);
- goto try_next_server;
-
- /* miscellaneous error */
- default:
- server->fs_act_jif = jiffies;
- case -ENOMEM:
- case -ENONET:
- /* tell the caller to accept the result */
- afs_put_server(server);
- _leave(" [local failure]");
- return 1;
+ ret = wait_on_bit(&volume->flags, AFS_VOLUME_WAIT, TASK_INTERRUPTIBLE);
+ if (ret == -ERESTARTSYS) {
+ _leave(" = %d", ret);
+ return ret;
}
- /* tell the caller to loop around and try the next server */
-try_next_server_upw:
- up_write(&volume->server_sem);
-try_next_server:
- afs_put_server(server);
- _leave(" [try next server]");
- return 0;
+ retries++;
+ if (retries == 4) {
+ _leave(" = -ESTALE");
+ return -ESTALE;
+ }
+ goto retry;
}