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-rw-r--r--fs/afs/vlocation.c1153
1 files changed, 469 insertions, 684 deletions
diff --git a/fs/afs/vlocation.c b/fs/afs/vlocation.c
index e48728c92175..60cb2f408c75 100644
--- a/fs/afs/vlocation.c
+++ b/fs/afs/vlocation.c
@@ -1,6 +1,6 @@
-/* volume location management
+/* AFS volume location management
*
- * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
@@ -12,130 +12,60 @@
#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 "volume.h"
-#include "cell.h"
-#include "cmservice.h"
-#include "fsclient.h"
-#include "vlclient.h"
-#include "kafstimod.h"
-#include <rxrpc/connection.h>
#include "internal.h"
-#define AFS_VLDB_TIMEOUT HZ*1000
+unsigned afs_vlocation_timeout = 10; /* volume location timeout in seconds */
+unsigned afs_vlocation_update_timeout = 10 * 60;
-static void afs_vlocation_update_timer(struct afs_timer *timer);
-static void afs_vlocation_update_attend(struct afs_async_op *op);
-static void afs_vlocation_update_discard(struct afs_async_op *op);
-static void __afs_put_vlocation(struct afs_vlocation *vlocation);
+static void afs_vlocation_reaper(struct work_struct *);
+static void afs_vlocation_updater(struct work_struct *);
-static void __afs_vlocation_timeout(struct afs_timer *timer)
-{
- struct afs_vlocation *vlocation =
- list_entry(timer, struct afs_vlocation, timeout);
-
- _debug("VL TIMEOUT [%s{u=%d}]",
- vlocation->vldb.name, atomic_read(&vlocation->usage));
-
- afs_vlocation_do_timeout(vlocation);
-}
-
-static const struct afs_timer_ops afs_vlocation_timer_ops = {
- .timed_out = __afs_vlocation_timeout,
-};
-
-static const struct afs_timer_ops afs_vlocation_update_timer_ops = {
- .timed_out = afs_vlocation_update_timer,
-};
-
-static const struct afs_async_op_ops afs_vlocation_update_op_ops = {
- .attend = afs_vlocation_update_attend,
- .discard = afs_vlocation_update_discard,
-};
-
-static LIST_HEAD(afs_vlocation_update_pendq); /* queue of VLs awaiting update */
-static struct afs_vlocation *afs_vlocation_update; /* VL currently being updated */
-static DEFINE_SPINLOCK(afs_vlocation_update_lock); /* lock guarding update queue */
-
-#ifdef AFS_CACHING_SUPPORT
-static cachefs_match_val_t afs_vlocation_cache_match(void *target,
- const void *entry);
-static void afs_vlocation_cache_update(void *source, void *entry);
-
-struct cachefs_index_def afs_vlocation_cache_index_def = {
- .name = "vldb",
- .data_size = sizeof(struct afs_cache_vlocation),
- .keys[0] = { CACHEFS_INDEX_KEYS_ASCIIZ, 64 },
- .match = afs_vlocation_cache_match,
- .update = afs_vlocation_cache_update,
-};
-#endif
+static LIST_HEAD(afs_vlocation_updates);
+static LIST_HEAD(afs_vlocation_graveyard);
+static DEFINE_SPINLOCK(afs_vlocation_updates_lock);
+static DEFINE_SPINLOCK(afs_vlocation_graveyard_lock);
+static DECLARE_DELAYED_WORK(afs_vlocation_reap, afs_vlocation_reaper);
+static DECLARE_DELAYED_WORK(afs_vlocation_update, afs_vlocation_updater);
+static struct workqueue_struct *afs_vlocation_update_worker;
/*
* iterate through the VL servers in a cell until one of them admits knowing
* about the volume in question
- * - caller must have cell->vl_sem write-locked
*/
-static int afs_vlocation_access_vl_by_name(struct afs_vlocation *vlocation,
- const char *name,
- unsigned namesz,
+static int afs_vlocation_access_vl_by_name(struct afs_vlocation *vl,
struct afs_cache_vlocation *vldb)
{
- struct afs_server *server = NULL;
- struct afs_cell *cell = vlocation->cell;
+ struct afs_cell *cell = vl->cell;
+ struct in_addr addr;
int count, ret;
- _enter("%s,%*.*s,%u", cell->name, namesz, namesz, name, namesz);
+ _enter("%s,%s", cell->name, vl->vldb.name);
+ down_write(&vl->cell->vl_sem);
ret = -ENOMEDIUM;
for (count = cell->vl_naddrs; count > 0; count--) {
- _debug("CellServ[%hu]: %08x",
- cell->vl_curr_svix,
- cell->vl_addrs[cell->vl_curr_svix].s_addr);
-
- /* try and create a server */
- ret = afs_server_lookup(cell,
- &cell->vl_addrs[cell->vl_curr_svix],
- &server);
- switch (ret) {
- case 0:
- break;
- case -ENOMEM:
- case -ENONET:
- goto out;
- default:
- goto rotate;
- }
+ addr = cell->vl_addrs[cell->vl_curr_svix];
+
+ _debug("CellServ[%hu]: %08x", cell->vl_curr_svix, addr.s_addr);
/* attempt to access the VL server */
- ret = afs_rxvl_get_entry_by_name(server, name, namesz, vldb);
+ ret = afs_vl_get_entry_by_name(&addr, vl->vldb.name, vldb,
+ &afs_sync_call);
switch (ret) {
case 0:
- afs_put_server(server);
goto out;
case -ENOMEM:
case -ENONET:
case -ENETUNREACH:
case -EHOSTUNREACH:
case -ECONNREFUSED:
- down_write(&server->sem);
- if (server->vlserver) {
- rxrpc_put_connection(server->vlserver);
- server->vlserver = NULL;
- }
- up_write(&server->sem);
- afs_put_server(server);
if (ret == -ENOMEM || ret == -ENONET)
goto out;
goto rotate;
case -ENOMEDIUM:
- afs_put_server(server);
goto out;
default:
- afs_put_server(server);
- ret = -ENOMEDIUM;
+ ret = -EIO;
goto rotate;
}
@@ -146,6 +76,7 @@ static int afs_vlocation_access_vl_by_name(struct afs_vlocation *vlocation,
}
out:
+ up_write(&vl->cell->vl_sem);
_leave(" = %d", ret);
return ret;
}
@@ -153,66 +84,56 @@ out:
/*
* iterate through the VL servers in a cell until one of them admits knowing
* about the volume in question
- * - caller must have cell->vl_sem write-locked
*/
-static int afs_vlocation_access_vl_by_id(struct afs_vlocation *vlocation,
+static int afs_vlocation_access_vl_by_id(struct afs_vlocation *vl,
afs_volid_t volid,
afs_voltype_t voltype,
struct afs_cache_vlocation *vldb)
{
- struct afs_server *server = NULL;
- struct afs_cell *cell = vlocation->cell;
+ struct afs_cell *cell = vl->cell;
+ struct in_addr addr;
int count, ret;
_enter("%s,%x,%d,", cell->name, volid, voltype);
+ down_write(&vl->cell->vl_sem);
ret = -ENOMEDIUM;
for (count = cell->vl_naddrs; count > 0; count--) {
- _debug("CellServ[%hu]: %08x",
- cell->vl_curr_svix,
- cell->vl_addrs[cell->vl_curr_svix].s_addr);
-
- /* try and create a server */
- ret = afs_server_lookup(cell,
- &cell->vl_addrs[cell->vl_curr_svix],
- &server);
- switch (ret) {
- case 0:
- break;
- case -ENOMEM:
- case -ENONET:
- goto out;
- default:
- goto rotate;
- }
+ addr = cell->vl_addrs[cell->vl_curr_svix];
+
+ _debug("CellServ[%hu]: %08x", cell->vl_curr_svix, addr.s_addr);
/* attempt to access the VL server */
- ret = afs_rxvl_get_entry_by_id(server, volid, voltype, vldb);
+ ret = afs_vl_get_entry_by_id(&addr, volid, voltype, vldb,
+ &afs_sync_call);
switch (ret) {
case 0:
- afs_put_server(server);
goto out;
case -ENOMEM:
case -ENONET:
case -ENETUNREACH:
case -EHOSTUNREACH:
case -ECONNREFUSED:
- down_write(&server->sem);
- if (server->vlserver) {
- rxrpc_put_connection(server->vlserver);
- server->vlserver = NULL;
- }
- up_write(&server->sem);
- afs_put_server(server);
if (ret == -ENOMEM || ret == -ENONET)
goto out;
goto rotate;
+ case -EBUSY:
+ vl->upd_busy_cnt++;
+ if (vl->upd_busy_cnt <= 3) {
+ if (vl->upd_busy_cnt > 1) {
+ /* second+ BUSY - sleep a little bit */
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(1);
+ __set_current_state(TASK_RUNNING);
+ }
+ continue;
+ }
+ break;
case -ENOMEDIUM:
- afs_put_server(server);
- goto out;
+ vl->upd_rej_cnt++;
+ goto rotate;
default:
- afs_put_server(server);
- ret = -ENOMEDIUM;
+ ret = -EIO;
goto rotate;
}
@@ -220,150 +141,83 @@ static int afs_vlocation_access_vl_by_id(struct afs_vlocation *vlocation,
rotate:
cell->vl_curr_svix++;
cell->vl_curr_svix %= cell->vl_naddrs;
+ vl->upd_busy_cnt = 0;
}
out:
+ if (ret < 0 && vl->upd_rej_cnt > 0) {
+ printk(KERN_NOTICE "kAFS:"
+ " Active volume no longer valid '%s'\n",
+ vl->vldb.name);
+ vl->valid = 0;
+ ret = -ENOMEDIUM;
+ }
+
+ up_write(&vl->cell->vl_sem);
_leave(" = %d", ret);
return ret;
}
/*
- * lookup volume location
- * - caller must have cell->vol_sem write-locked
- * - iterate through the VL servers in a cell until one of them admits knowing
- * about the volume in question
- * - lookup in the local cache if not able to find on the VL server
- * - insert/update in the local cache if did get a VL response
+ * allocate a volume location record
*/
-int afs_vlocation_lookup(struct afs_cell *cell,
- const char *name,
- unsigned namesz,
- struct afs_vlocation **_vlocation)
+static struct afs_vlocation *afs_vlocation_alloc(struct afs_cell *cell,
+ const char *name,
+ size_t namesz)
{
- struct afs_cache_vlocation vldb;
- struct afs_vlocation *vlocation;
- afs_voltype_t voltype;
- afs_volid_t vid;
- int active = 0, ret;
-
- _enter("{%s},%*.*s,%u,", cell->name, namesz, namesz, name, namesz);
-
- if (namesz > sizeof(vlocation->vldb.name)) {
- _leave(" = -ENAMETOOLONG");
- return -ENAMETOOLONG;
- }
-
- /* search the cell's active list first */
- list_for_each_entry(vlocation, &cell->vl_list, link) {
- if (namesz < sizeof(vlocation->vldb.name) &&
- vlocation->vldb.name[namesz] != '\0')
- continue;
-
- if (memcmp(vlocation->vldb.name, name, namesz) == 0)
- goto found_in_memory;
- }
-
- /* search the cell's graveyard list second */
- spin_lock(&cell->vl_gylock);
- list_for_each_entry(vlocation, &cell->vl_graveyard, link) {
- if (namesz < sizeof(vlocation->vldb.name) &&
- vlocation->vldb.name[namesz] != '\0')
- continue;
-
- if (memcmp(vlocation->vldb.name, name, namesz) == 0)
- goto found_in_graveyard;
- }
- spin_unlock(&cell->vl_gylock);
-
- /* not in the cell's in-memory lists - create a new record */
- vlocation = kzalloc(sizeof(struct afs_vlocation), GFP_KERNEL);
- if (!vlocation)
- return -ENOMEM;
-
- atomic_set(&vlocation->usage, 1);
- INIT_LIST_HEAD(&vlocation->link);
- rwlock_init(&vlocation->lock);
- memcpy(vlocation->vldb.name, name, namesz);
-
- afs_timer_init(&vlocation->timeout, &afs_vlocation_timer_ops);
- afs_timer_init(&vlocation->upd_timer, &afs_vlocation_update_timer_ops);
- afs_async_op_init(&vlocation->upd_op, &afs_vlocation_update_op_ops);
-
- afs_get_cell(cell);
- vlocation->cell = cell;
-
- list_add_tail(&vlocation->link, &cell->vl_list);
-
-#ifdef AFS_CACHING_SUPPORT
- /* we want to store it in the cache, plus it might already be
- * encached */
- cachefs_acquire_cookie(cell->cache,
- &afs_volume_cache_index_def,
- vlocation,
- &vlocation->cache);
-
- if (vlocation->valid)
- goto found_in_cache;
-#endif
-
- /* try to look up an unknown volume in the cell VL databases by name */
- ret = afs_vlocation_access_vl_by_name(vlocation, name, namesz, &vldb);
- if (ret < 0) {
- printk("kAFS: failed to locate '%*.*s' in cell '%s'\n",
- namesz, namesz, name, cell->name);
- goto error;
+ struct afs_vlocation *vl;
+
+ vl = kzalloc(sizeof(struct afs_vlocation), GFP_KERNEL);
+ if (vl) {
+ vl->cell = cell;
+ vl->state = AFS_VL_NEW;
+ atomic_set(&vl->usage, 1);
+ INIT_LIST_HEAD(&vl->link);
+ INIT_LIST_HEAD(&vl->grave);
+ INIT_LIST_HEAD(&vl->update);
+ init_waitqueue_head(&vl->waitq);
+ rwlock_init(&vl->lock);
+ memcpy(vl->vldb.name, name, namesz);
}
- goto found_on_vlserver;
-
-found_in_graveyard:
- /* found in the graveyard - resurrect */
- _debug("found in graveyard");
- atomic_inc(&vlocation->usage);
- list_move_tail(&vlocation->link, &cell->vl_list);
- spin_unlock(&cell->vl_gylock);
-
- afs_kafstimod_del_timer(&vlocation->timeout);
- goto active;
-
-found_in_memory:
- /* found in memory - check to see if it's active */
- _debug("found in memory");
- atomic_inc(&vlocation->usage);
+ _leave(" = %p", vl);
+ return vl;
+}
-active:
- active = 1;
+/*
+ * update record if we found it in the cache
+ */
+static int afs_vlocation_update_record(struct afs_vlocation *vl,
+ struct afs_cache_vlocation *vldb)
+{
+ afs_voltype_t voltype;
+ afs_volid_t vid;
+ int ret;
-#ifdef AFS_CACHING_SUPPORT
-found_in_cache:
-#endif
/* try to look up a cached volume in the cell VL databases by ID */
- _debug("found in cache");
-
_debug("Locally Cached: %s %02x { %08x(%x) %08x(%x) %08x(%x) }",
- vlocation->vldb.name,
- vlocation->vldb.vidmask,
- ntohl(vlocation->vldb.servers[0].s_addr),
- vlocation->vldb.srvtmask[0],
- ntohl(vlocation->vldb.servers[1].s_addr),
- vlocation->vldb.srvtmask[1],
- ntohl(vlocation->vldb.servers[2].s_addr),
- vlocation->vldb.srvtmask[2]
- );
+ vl->vldb.name,
+ vl->vldb.vidmask,
+ ntohl(vl->vldb.servers[0].s_addr),
+ vl->vldb.srvtmask[0],
+ ntohl(vl->vldb.servers[1].s_addr),
+ vl->vldb.srvtmask[1],
+ ntohl(vl->vldb.servers[2].s_addr),
+ vl->vldb.srvtmask[2]);
_debug("Vids: %08x %08x %08x",
- vlocation->vldb.vid[0],
- vlocation->vldb.vid[1],
- vlocation->vldb.vid[2]);
+ vl->vldb.vid[0],
+ vl->vldb.vid[1],
+ vl->vldb.vid[2]);
- if (vlocation->vldb.vidmask & AFS_VOL_VTM_RW) {
- vid = vlocation->vldb.vid[0];
+ if (vl->vldb.vidmask & AFS_VOL_VTM_RW) {
+ vid = vl->vldb.vid[0];
voltype = AFSVL_RWVOL;
- } else if (vlocation->vldb.vidmask & AFS_VOL_VTM_RO) {
- vid = vlocation->vldb.vid[1];
+ } else if (vl->vldb.vidmask & AFS_VOL_VTM_RO) {
+ vid = vl->vldb.vid[1];
voltype = AFSVL_ROVOL;
- } else if (vlocation->vldb.vidmask & AFS_VOL_VTM_BAK) {
- vid = vlocation->vldb.vid[2];
+ } else if (vl->vldb.vidmask & AFS_VOL_VTM_BAK) {
+ vid = vl->vldb.vid[2];
voltype = AFSVL_BACKVOL;
} else {
BUG();
@@ -371,551 +225,482 @@ found_in_cache:
voltype = 0;
}
- ret = afs_vlocation_access_vl_by_id(vlocation, vid, voltype, &vldb);
+ /* contact the server to make sure the volume is still available
+ * - TODO: need to handle disconnected operation here
+ */
+ ret = afs_vlocation_access_vl_by_id(vl, vid, voltype, vldb);
switch (ret) {
/* net error */
default:
- printk("kAFS: failed to volume '%*.*s' (%x) up in '%s': %d\n",
- namesz, namesz, name, vid, cell->name, ret);
- goto error;
+ printk(KERN_WARNING "kAFS:"
+ " failed to update volume '%s' (%x) up in '%s': %d\n",
+ vl->vldb.name, vid, vl->cell->name, ret);
+ _leave(" = %d", ret);
+ return ret;
/* pulled from local cache into memory */
case 0:
- goto found_on_vlserver;
+ _leave(" = 0");
+ return 0;
/* uh oh... looks like the volume got deleted */
case -ENOMEDIUM:
- printk("kAFS: volume '%*.*s' (%x) does not exist '%s'\n",
- namesz, namesz, name, vid, cell->name);
+ printk(KERN_ERR "kAFS:"
+ " volume '%s' (%x) does not exist '%s'\n",
+ vl->vldb.name, vid, vl->cell->name);
/* TODO: make existing record unavailable */
- goto error;
+ _leave(" = %d", ret);
+ return ret;
}
+}
-found_on_vlserver:
- _debug("Done VL Lookup: %*.*s %02x { %08x(%x) %08x(%x) %08x(%x) }",
- namesz, namesz, name,
- vldb.vidmask,
- ntohl(vldb.servers[0].s_addr), vldb.srvtmask[0],
- ntohl(vldb.servers[1].s_addr), vldb.srvtmask[1],
- ntohl(vldb.servers[2].s_addr), vldb.srvtmask[2]
- );
-
- _debug("Vids: %08x %08x %08x", vldb.vid[0], vldb.vid[1], vldb.vid[2]);
+/*
+ * apply the update to a VL record
+ */
+static void afs_vlocation_apply_update(struct afs_vlocation *vl,
+ struct afs_cache_vlocation *vldb)
+{
+ _debug("Done VL Lookup: %s %02x { %08x(%x) %08x(%x) %08x(%x) }",
+ vldb->name, vldb->vidmask,
+ ntohl(vldb->servers[0].s_addr), vldb->srvtmask[0],
+ ntohl(vldb->servers[1].s_addr), vldb->srvtmask[1],
+ ntohl(vldb->servers[2].s_addr), vldb->srvtmask[2]);
- if ((namesz < sizeof(vlocation->vldb.name) &&
- vlocation->vldb.name[namesz] != '\0') ||
- memcmp(vldb.name, name, namesz) != 0)
- printk("kAFS: name of volume '%*.*s' changed to '%s' on server\n",
- namesz, namesz, name, vldb.name);
+ _debug("Vids: %08x %08x %08x",
+ vldb->vid[0], vldb->vid[1], vldb->vid[2]);
- memcpy(&vlocation->vldb, &vldb, sizeof(vlocation->vldb));
+ if (strcmp(vldb->name, vl->vldb.name) != 0)
+ printk(KERN_NOTICE "kAFS:"
+ " name of volume '%s' changed to '%s' on server\n",
+ vl->vldb.name, vldb->name);
- afs_kafstimod_add_timer(&vlocation->upd_timer, 10 * HZ);
+ vl->vldb = *vldb;
#ifdef AFS_CACHING_SUPPORT
/* update volume entry in local cache */
- cachefs_update_cookie(vlocation->cache);
-#endif
-
- *_vlocation = vlocation;
- _leave(" = 0 (%p)",vlocation);
- return 0;
-
-error:
- if (vlocation) {
- if (active) {
- __afs_put_vlocation(vlocation);
- } else {
- list_del(&vlocation->link);
-#ifdef AFS_CACHING_SUPPORT
- cachefs_relinquish_cookie(vlocation->cache, 0);
+ cachefs_update_cookie(vl->cache);
#endif
- afs_put_cell(vlocation->cell);
- kfree(vlocation);
- }
- }
-
- _leave(" = %d", ret);
- return ret;
}
/*
- * finish using a volume location record
- * - caller must have cell->vol_sem write-locked
+ * fill in a volume location record, consulting the cache and the VL server
+ * both
*/
-static void __afs_put_vlocation(struct afs_vlocation *vlocation)
+static int afs_vlocation_fill_in_record(struct afs_vlocation *vl)
{
- struct afs_cell *cell;
+ struct afs_cache_vlocation vldb;
+ int ret;
- if (!vlocation)
- return;
+ _enter("");
- _enter("%s", vlocation->vldb.name);
+ ASSERTCMP(vl->valid, ==, 0);
- cell = vlocation->cell;
+ memset(&vldb, 0, sizeof(vldb));
- /* sanity check */
- BUG_ON(atomic_read(&vlocation->usage) <= 0);
+ /* see if we have an in-cache copy (will set vl->valid if there is) */
+#ifdef AFS_CACHING_SUPPORT
+ cachefs_acquire_cookie(cell->cache,
+ &afs_volume_cache_index_def,
+ vlocation,
+ &vl->cache);
+#endif
- spin_lock(&cell->vl_gylock);
- if (likely(!atomic_dec_and_test(&vlocation->usage))) {
- spin_unlock(&cell->vl_gylock);
- _leave("");
- return;
+ if (vl->valid) {
+ /* try to update a known volume in the cell VL databases by
+ * ID as the name may have changed */
+ _debug("found in cache");
+ ret = afs_vlocation_update_record(vl, &vldb);
+ } else {
+ /* try to look up an unknown volume in the cell VL databases by
+ * name */
+ ret = afs_vlocation_access_vl_by_name(vl, &vldb);
+ if (ret < 0) {
+ printk("kAFS: failed to locate '%s' in cell '%s'\n",
+ vl->vldb.name, vl->cell->name);
+ return ret;
+ }
}
- /* move to graveyard queue */
- list_move_tail(&vlocation->link,&cell->vl_graveyard);
-
- /* remove from pending timeout queue (refcounted if actually being
- * updated) */
- list_del_init(&vlocation->upd_op.link);
-
- /* time out in 10 secs */
- afs_kafstimod_del_timer(&vlocation->upd_timer);
- afs_kafstimod_add_timer(&vlocation->timeout, 10 * HZ);
-
- spin_unlock(&cell->vl_gylock);
-
- _leave(" [killed]");
+ afs_vlocation_apply_update(vl, &vldb);
+ _leave(" = 0");
+ return 0;
}
/*
- * finish using a volume location record
+ * queue a vlocation record for updates
*/
-void afs_put_vlocation(struct afs_vlocation *vlocation)
+void afs_vlocation_queue_for_updates(struct afs_vlocation *vl)
{
- if (vlocation) {
- struct afs_cell *cell = vlocation->cell;
+ struct afs_vlocation *xvl;
- down_write(&cell->vl_sem);
- __afs_put_vlocation(vlocation);
- up_write(&cell->vl_sem);
+ /* wait at least 10 minutes before updating... */
+ vl->update_at = get_seconds() + afs_vlocation_update_timeout;
+
+ spin_lock(&afs_vlocation_updates_lock);
+
+ if (!list_empty(&afs_vlocation_updates)) {
+ /* ... but wait at least 1 second more than the newest record
+ * already queued so that we don't spam the VL server suddenly
+ * with lots of requests
+ */
+ xvl = list_entry(afs_vlocation_updates.prev,
+ struct afs_vlocation, update);
+ if (vl->update_at <= xvl->update_at)
+ vl->update_at = xvl->update_at + 1;
+ } else {
+ queue_delayed_work(afs_vlocation_update_worker,
+ &afs_vlocation_update,
+ afs_vlocation_update_timeout * HZ);
}
+
+ list_add_tail(&vl->update, &afs_vlocation_updates);
+ spin_unlock(&afs_vlocation_updates_lock);
}
/*
- * timeout vlocation record
- * - removes from the cell's graveyard if the usage count is zero
+ * lookup volume location
+ * - iterate through the VL servers in a cell until one of them admits knowing
+ * about the volume in question
+ * - lookup in the local cache if not able to find on the VL server
+ * - insert/update in the local cache if did get a VL response
*/
-void afs_vlocation_do_timeout(struct afs_vlocation *vlocation)
+struct afs_vlocation *afs_vlocation_lookup(struct afs_cell *cell,
+ const char *name,
+ size_t namesz)
{
- struct afs_cell *cell;
-
- _enter("%s", vlocation->vldb.name);
-
- cell = vlocation->cell;
+ struct afs_vlocation *vl;
+ int ret;
- BUG_ON(atomic_read(&vlocation->usage) < 0);
+ _enter("{%s},%*.*s,%zu",
+ cell->name, (int) namesz, (int) namesz, name, namesz);
- /* remove from graveyard if still dead */
- spin_lock(&cell->vl_gylock);
- if (atomic_read(&vlocation->usage) == 0)
- list_del_init(&vlocation->link);
- else
- vlocation = NULL;
- spin_unlock(&cell->vl_gylock);
+ if (namesz > sizeof(vl->vldb.name)) {
+ _leave(" = -ENAMETOOLONG");
+ return ERR_PTR(-ENAMETOOLONG);
+ }
- if (!vlocation) {
- _leave("");
- return; /* resurrected */
+ /* see if we have an in-memory copy first */
+ down_write(&cell->vl_sem);
+ spin_lock(&cell->vl_lock);
+ list_for_each_entry(vl, &cell->vl_list, link) {
+ if (vl->vldb.name[namesz] != '\0')
+ continue;
+ if (memcmp(vl->vldb.name, name, namesz) == 0)
+ goto found_in_memory;
}
+ spin_unlock(&cell->vl_lock);
- /* we can now destroy it properly */
-#ifdef AFS_CACHING_SUPPORT
- cachefs_relinquish_cookie(vlocation->cache, 0);
-#endif
- afs_put_cell(cell);
+ /* not in the cell's in-memory lists - create a new record */
+ vl = afs_vlocation_alloc(cell, name, namesz);
+ if (!vl) {
+ up_write(&cell->vl_sem);
+ return ERR_PTR(-ENOMEM);
+ }
- kfree(vlocation);
+ afs_get_cell(cell);
- _leave(" [destroyed]");
-}
+ list_add_tail(&vl->link, &cell->vl_list);
+ vl->state = AFS_VL_CREATING;
+ up_write(&cell->vl_sem);
-/*
- * send an update operation to the currently selected server
- */
-static int afs_vlocation_update_begin(struct afs_vlocation *vlocation)
-{
- afs_voltype_t voltype;
- afs_volid_t vid;
- int ret;
+fill_in_record:
+ ret = afs_vlocation_fill_in_record(vl);
+ if (ret < 0)
+ goto error_abandon;
+ vl->state = AFS_VL_VALID;
+ wake_up(&vl->waitq);
- _enter("%s{ufs=%u ucs=%u}",
- vlocation->vldb.name,
- vlocation->upd_first_svix,
- vlocation->upd_curr_svix);
+ /* schedule for regular updates */
+ afs_vlocation_queue_for_updates(vl);
+ goto success;
- /* try to look up a cached volume in the cell VL databases by ID */
- if (vlocation->vldb.vidmask & AFS_VOL_VTM_RW) {
- vid = vlocation->vldb.vid[0];
- voltype = AFSVL_RWVOL;
- } else if (vlocation->vldb.vidmask & AFS_VOL_VTM_RO) {
- vid = vlocation->vldb.vid[1];
- voltype = AFSVL_ROVOL;
- } else if (vlocation->vldb.vidmask & AFS_VOL_VTM_BAK) {
- vid = vlocation->vldb.vid[2];
- voltype = AFSVL_BACKVOL;
- } else {
- BUG();
- vid = 0;
- voltype = 0;
+found_in_memory:
+ /* found in memory */
+ _debug("found in memory");
+ atomic_inc(&vl->usage);
+ spin_unlock(&cell->vl_lock);
+ if (!list_empty(&vl->grave)) {
+ spin_lock(&afs_vlocation_graveyard_lock);
+ list_del_init(&vl->grave);
+ spin_unlock(&afs_vlocation_graveyard_lock);
}
+ up_write(&cell->vl_sem);
- /* contact the chosen server */
- ret = afs_server_lookup(
- vlocation->cell,
- &vlocation->cell->vl_addrs[vlocation->upd_curr_svix],
- &vlocation->upd_op.server);
+ /* see if it was an abandoned record that we might try filling in */
+ while (vl->state != AFS_VL_VALID) {
+ afs_vlocation_state_t state = vl->state;
- switch (ret) {
- case 0:
- break;
- case -ENOMEM:
- case -ENONET:
- default:
- _leave(" = %d", ret);
- return ret;
- }
+ _debug("invalid [state %d]", state);
- /* initiate the update operation */
- ret = afs_rxvl_get_entry_by_id_async(&vlocation->upd_op, vid, voltype);
- if (ret < 0) {
- _leave(" = %d", ret);
- return ret;
+ if ((state == AFS_VL_NEW || state == AFS_VL_NO_VOLUME)) {
+ if (cmpxchg(&vl->state, state, AFS_VL_CREATING) ==
+ state)
+ goto fill_in_record;
+ continue;
+ }
+
+ /* must now wait for creation or update by someone else to
+ * complete */
+ _debug("wait");
+
+ ret = wait_event_interruptible(
+ vl->waitq,
+ vl->state == AFS_VL_NEW ||
+ vl->state == AFS_VL_VALID ||
+ vl->state == AFS_VL_NO_VOLUME);
+ if (ret < 0)
+ goto error;
}
+success:
+ _leave(" = %p",vl);
+ return vl;
+
+error_abandon:
+ vl->state = AFS_VL_NEW;
+ wake_up(&vl->waitq);
+error:
+ ASSERT(vl != NULL);
+ afs_put_vlocation(vl);
_leave(" = %d", ret);
- return ret;
+ return ERR_PTR(ret);
}
/*
- * abandon updating a VL record
- * - does not restart the update timer
+ * finish using a volume location record
*/
-static void afs_vlocation_update_abandon(struct afs_vlocation *vlocation,
- afs_vlocation_upd_t state,
- int ret)
+void afs_put_vlocation(struct afs_vlocation *vl)
{
- _enter("%s,%u", vlocation->vldb.name, state);
-
- if (ret < 0)
- printk("kAFS: Abandoning VL update '%s': %d\n",
- vlocation->vldb.name, ret);
-
- /* discard the server record */
- afs_put_server(vlocation->upd_op.server);
- vlocation->upd_op.server = NULL;
+ if (!vl)
+ return;
- spin_lock(&afs_vlocation_update_lock);
- afs_vlocation_update = NULL;
- vlocation->upd_state = state;
+ _enter("%s", vl->vldb.name);
- /* TODO: start updating next VL record on pending list */
+ ASSERTCMP(atomic_read(&vl->usage), >, 0);
- spin_unlock(&afs_vlocation_update_lock);
+ if (likely(!atomic_dec_and_test(&vl->usage))) {
+ _leave("");
+ return;
+ }
- _leave("");
+ spin_lock(&afs_vlocation_graveyard_lock);
+ if (atomic_read(&vl->usage) == 0) {
+ _debug("buried");
+ list_move_tail(&vl->grave, &afs_vlocation_graveyard);
+ vl->time_of_death = get_seconds();
+ schedule_delayed_work(&afs_vlocation_reap,
+ afs_vlocation_timeout * HZ);
+
+ /* suspend updates on this record */
+ if (!list_empty(&vl->update)) {
+ spin_lock(&afs_vlocation_updates_lock);
+ list_del_init(&vl->update);
+ spin_unlock(&afs_vlocation_updates_lock);
+ }
+ }
+ spin_unlock(&afs_vlocation_graveyard_lock);
+ _leave(" [killed?]");
}
/*
- * handle periodic update timeouts and busy retry timeouts
- * - called from kafstimod
+ * destroy a dead volume location record
*/
-static void afs_vlocation_update_timer(struct afs_timer *timer)
+static void afs_vlocation_destroy(struct afs_vlocation *vl)
{
- struct afs_vlocation *vlocation =
- list_entry(timer, struct afs_vlocation, upd_timer);
- int ret;
+ _enter("%p", vl);
- _enter("%s", vlocation->vldb.name);
+#ifdef AFS_CACHING_SUPPORT
+ cachefs_relinquish_cookie(vl->cache, 0);
+#endif
- /* only update if not in the graveyard (defend against putting too) */
- spin_lock(&vlocation->cell->vl_gylock);
+ afs_put_cell(vl->cell);
+ kfree(vl);
+}
+
+/*
+ * reap dead volume location records
+ */
+static void afs_vlocation_reaper(struct work_struct *work)
+{
+ LIST_HEAD(corpses);
+ struct afs_vlocation *vl;
+ unsigned long delay, expiry;
+ time_t now;
- if (!atomic_read(&vlocation->usage))
- goto out_unlock1;
+ _enter("");
- spin_lock(&afs_vlocation_update_lock);
+ now = get_seconds();
+ spin_lock(&afs_vlocation_graveyard_lock);
+
+ while (!list_empty(&afs_vlocation_graveyard)) {
+ vl = list_entry(afs_vlocation_graveyard.next,
+ struct afs_vlocation, grave);
+
+ _debug("check %p", vl);
+
+ /* the queue is ordered most dead first */
+ expiry = vl->time_of_death + afs_vlocation_timeout;
+ if (expiry > now) {
+ delay = (expiry - now) * HZ;
+ _debug("delay %lu", delay);
+ if (!schedule_delayed_work(&afs_vlocation_reap,
+ delay)) {
+ cancel_delayed_work(&afs_vlocation_reap);
+ schedule_delayed_work(&afs_vlocation_reap,
+ delay);
+ }
+ break;
+ }
- /* if we were woken up due to EBUSY sleep then restart immediately if
- * possible or else jump to front of pending queue */
- if (vlocation->upd_state == AFS_VLUPD_BUSYSLEEP) {
- if (afs_vlocation_update) {
- list_add(&vlocation->upd_op.link,
- &afs_vlocation_update_pendq);
+ spin_lock(&vl->cell->vl_lock);
+ if (atomic_read(&vl->usage) > 0) {
+ _debug("no reap");
+ list_del_init(&vl->grave);
} else {
- afs_get_vlocation(vlocation);
- afs_vlocation_update = vlocation;
- vlocation->upd_state = AFS_VLUPD_INPROGRESS;
+ _debug("reap");
+ list_move_tail(&vl->grave, &corpses);
+ list_del_init(&vl->link);
}
- goto out_unlock2;
+ spin_unlock(&vl->cell->vl_lock);
}
- /* put on pending queue if there's already another update in progress */
- if (afs_vlocation_update) {
- vlocation->upd_state = AFS_VLUPD_PENDING;
- list_add_tail(&vlocation->upd_op.link,
- &afs_vlocation_update_pendq);
- goto out_unlock2;
- }
+ spin_unlock(&afs_vlocation_graveyard_lock);
- /* hold a ref on it while actually updating */
- afs_get_vlocation(vlocation);
- afs_vlocation_update = vlocation;
- vlocation->upd_state = AFS_VLUPD_INPROGRESS;
-
- spin_unlock(&afs_vlocation_update_lock);
- spin_unlock(&vlocation->cell->vl_gylock);
-
- /* okay... we can start the update */
- _debug("BEGIN VL UPDATE [%s]", vlocation->vldb.name);
- vlocation->upd_first_svix = vlocation->cell->vl_curr_svix;
- vlocation->upd_curr_svix = vlocation->upd_first_svix;
- vlocation->upd_rej_cnt = 0;
- vlocation->upd_busy_cnt = 0;
-
- ret = afs_vlocation_update_begin(vlocation);
- if (ret < 0) {
- afs_vlocation_update_abandon(vlocation, AFS_VLUPD_SLEEP, ret);
- afs_kafstimod_add_timer(&vlocation->upd_timer,
- AFS_VLDB_TIMEOUT);
- afs_put_vlocation(vlocation);
+ /* now reap the corpses we've extracted */
+ while (!list_empty(&corpses)) {
+ vl = list_entry(corpses.next, struct afs_vlocation, grave);
+ list_del(&vl->grave);
+ afs_vlocation_destroy(vl);
}
_leave("");
- return;
+}
-out_unlock2:
- spin_unlock(&afs_vlocation_update_lock);
-out_unlock1:
- spin_unlock(&vlocation->cell->vl_gylock);
- _leave("");
+/*
+ * initialise the VL update process
+ */
+int __init afs_vlocation_update_init(void)
+{
+ afs_vlocation_update_worker =
+ create_singlethread_workqueue("kafs_vlupdated");
+ return afs_vlocation_update_worker ? 0 : -ENOMEM;
+}
+
+/*
+ * discard all the volume location records for rmmod
+ */
+void __exit afs_vlocation_purge(void)
+{
+ afs_vlocation_timeout = 0;
+
+ spin_lock(&afs_vlocation_updates_lock);
+ list_del_init(&afs_vlocation_updates);
+ spin_unlock(&afs_vlocation_updates_lock);
+ cancel_delayed_work(&afs_vlocation_update);
+ queue_delayed_work(afs_vlocation_update_worker,
+ &afs_vlocation_update, 0);
+ destroy_workqueue(afs_vlocation_update_worker);
+
+ cancel_delayed_work(&afs_vlocation_reap);
+ schedule_delayed_work(&afs_vlocation_reap, 0);
}
/*
- * attend to an update operation upon which an event happened
- * - called in kafsasyncd context
+ * update a volume location
*/
-static void afs_vlocation_update_attend(struct afs_async_op *op)
+static void afs_vlocation_updater(struct work_struct *work)
{
struct afs_cache_vlocation vldb;
- struct afs_vlocation *vlocation =
- list_entry(op, struct afs_vlocation, upd_op);
- unsigned tmp;
+ struct afs_vlocation *vl, *xvl;
+ time_t now;
+ long timeout;
int ret;
- _enter("%s", vlocation->vldb.name);
-
- ret = afs_rxvl_get_entry_by_id_async2(op, &vldb);
- switch (ret) {
- case -EAGAIN:
- _leave(" [unfinished]");
- return;
-
- case 0:
- _debug("END VL UPDATE: %d\n", ret);
- vlocation->valid = 1;
-
- _debug("Done VL Lookup: %02x { %08x(%x) %08x(%x) %08x(%x) }",
- vldb.vidmask,
- ntohl(vldb.servers[0].s_addr), vldb.srvtmask[0],
- ntohl(vldb.servers[1].s_addr), vldb.srvtmask[1],
- ntohl(vldb.servers[2].s_addr), vldb.srvtmask[2]
- );
-
- _debug("Vids: %08x %08x %08x",
- vldb.vid[0], vldb.vid[1], vldb.vid[2]);
-
- afs_vlocation_update_abandon(vlocation, AFS_VLUPD_SLEEP, 0);
-
- down_write(&vlocation->cell->vl_sem);
-
- /* actually update the cache */
- if (strncmp(vldb.name, vlocation->vldb.name,
- sizeof(vlocation->vldb.name)) != 0)
- printk("kAFS: name of volume '%s'"
- " changed to '%s' on server\n",
- vlocation->vldb.name, vldb.name);
-
- memcpy(&vlocation->vldb, &vldb, sizeof(vlocation->vldb));
-
-#if 0
- /* TODO update volume entry in local cache */
-#endif
-
- up_write(&vlocation->cell->vl_sem);
-
- if (ret < 0)
- printk("kAFS: failed to update local cache: %d\n", ret);
-
- afs_kafstimod_add_timer(&vlocation->upd_timer,
- AFS_VLDB_TIMEOUT);
- afs_put_vlocation(vlocation);
- _leave(" [found]");
- return;
-
- case -ENOMEDIUM:
- vlocation->upd_rej_cnt++;
- goto try_next;
-
- /* the server is locked - retry in a very short while */
- case -EBUSY:
- vlocation->upd_busy_cnt++;
- if (vlocation->upd_busy_cnt > 3)
- goto try_next; /* too many retries */
-
- afs_vlocation_update_abandon(vlocation,
- AFS_VLUPD_BUSYSLEEP, 0);
- afs_kafstimod_add_timer(&vlocation->upd_timer, HZ / 2);
- afs_put_vlocation(vlocation);
- _leave(" [busy]");
- return;
-
- case -ENETUNREACH:
- case -EHOSTUNREACH:
- case -ECONNREFUSED:
- case -EREMOTEIO:
- /* record bad vlserver info in the cell too
- * - TODO: use down_write_trylock() if available
- */
- if (vlocation->upd_curr_svix == vlocation->cell->vl_curr_svix)
- vlocation->cell->vl_curr_svix =
- vlocation->cell->vl_curr_svix %
- vlocation->cell->vl_naddrs;
-
- case -EBADRQC:
- case -EINVAL:
- case -EACCES:
- case -EBADMSG:
- goto try_next;
-
- default:
- goto abandon;
- }
-
- /* try contacting the next server */
-try_next:
- vlocation->upd_busy_cnt = 0;
-
- /* discard the server record */
- afs_put_server(vlocation->upd_op.server);
- vlocation->upd_op.server = NULL;
+ _enter("");
- tmp = vlocation->cell->vl_naddrs;
- if (tmp == 0)
- goto abandon;
+ now = get_seconds();
- vlocation->upd_curr_svix++;
- if (vlocation->upd_curr_svix >= tmp)
- vlocation->upd_curr_svix = 0;
- if (vlocation->upd_first_svix >= tmp)
- vlocation->upd_first_svix = tmp - 1;
+ /* find a record to update */
+ spin_lock(&afs_vlocation_updates_lock);
+ for (;;) {
+ if (list_empty(&afs_vlocation_updates)) {
+ spin_unlock(&afs_vlocation_updates_lock);
+ _leave(" [nothing]");
+ return;
+ }
- /* move to the next server */
- if (vlocation->upd_curr_svix != vlocation->upd_first_svix) {
- afs_vlocation_update_begin(vlocation);
- _leave(" [next]");
- return;
+ vl = list_entry(afs_vlocation_updates.next,
+ struct afs_vlocation, update);
+ if (atomic_read(&vl->usage) > 0)
+ break;
+ list_del_init(&vl->update);
}
- /* run out of servers to try - was the volume rejected? */
- if (vlocation->upd_rej_cnt > 0) {
- printk("kAFS: Active volume no longer valid '%s'\n",
- vlocation->vldb.name);
- vlocation->valid = 0;
- afs_vlocation_update_abandon(vlocation, AFS_VLUPD_SLEEP, 0);
- afs_kafstimod_add_timer(&vlocation->upd_timer,
- AFS_VLDB_TIMEOUT);
- afs_put_vlocation(vlocation);
- _leave(" [invalidated]");
+ timeout = vl->update_at - now;
+ if (timeout > 0) {
+ queue_delayed_work(afs_vlocation_update_worker,
+ &afs_vlocation_update, timeout * HZ);
+ spin_unlock(&afs_vlocation_updates_lock);
+ _leave(" [nothing]");
return;
}
- /* abandon the update */
-abandon:
- afs_vlocation_update_abandon(vlocation, AFS_VLUPD_SLEEP, ret);
- afs_kafstimod_add_timer(&vlocation->upd_timer, HZ * 10);
- afs_put_vlocation(vlocation);
- _leave(" [abandoned]");
-}
+ list_del_init(&vl->update);
+ atomic_inc(&vl->usage);
+ spin_unlock(&afs_vlocation_updates_lock);
-/*
- * deal with an update operation being discarded
- * - called in kafsasyncd context when it's dying due to rmmod
- * - the call has already been aborted and put()'d
- */
-static void afs_vlocation_update_discard(struct afs_async_op *op)
-{
- struct afs_vlocation *vlocation =
- list_entry(op, struct afs_vlocation, upd_op);
-
- _enter("%s", vlocation->vldb.name);
+ /* we can now perform the update */
+ _debug("update %s", vl->vldb.name);
+ vl->state = AFS_VL_UPDATING;
+ vl->upd_rej_cnt = 0;
+ vl->upd_busy_cnt = 0;
- afs_put_server(op->server);
- op->server = NULL;
-
- afs_put_vlocation(vlocation);
+ ret = afs_vlocation_update_record(vl, &vldb);
+ switch (ret) {
+ case 0:
+ afs_vlocation_apply_update(vl, &vldb);
+ vl->state = AFS_VL_VALID;
+ break;
+ case -ENOMEDIUM:
+ vl->state = AFS_VL_VOLUME_DELETED;
+ break;
+ default:
+ vl->state = AFS_VL_UNCERTAIN;
+ break;
+ }
- _leave("");
-}
+ /* and then reschedule */
+ _debug("reschedule");
+ vl->update_at = get_seconds() + afs_vlocation_update_timeout;
-/*
- * match a VLDB record stored in the cache
- * - may also load target from entry
- */
-#ifdef AFS_CACHING_SUPPORT
-static cachefs_match_val_t afs_vlocation_cache_match(void *target,
- const void *entry)
-{
- const struct afs_cache_vlocation *vldb = entry;
- struct afs_vlocation *vlocation = target;
-
- _enter("{%s},{%s}", vlocation->vldb.name, vldb->name);
-
- if (strncmp(vlocation->vldb.name, vldb->name, sizeof(vldb->name)) == 0
- ) {
- if (!vlocation->valid ||
- vlocation->vldb.rtime == vldb->rtime
- ) {
- vlocation->vldb = *vldb;
- vlocation->valid = 1;
- _leave(" = SUCCESS [c->m]");
- return CACHEFS_MATCH_SUCCESS;
- } else if (memcmp(&vlocation->vldb, vldb, sizeof(*vldb)) != 0) {
- /* delete if VIDs for this name differ */
- if (memcmp(&vlocation->vldb.vid,
- &vldb->vid,
- sizeof(vldb->vid)) != 0) {
- _leave(" = DELETE");
- return CACHEFS_MATCH_SUCCESS_DELETE;
- }
+ spin_lock(&afs_vlocation_updates_lock);
- _leave(" = UPDATE");
- return CACHEFS_MATCH_SUCCESS_UPDATE;
- } else {
- _leave(" = SUCCESS");
- return CACHEFS_MATCH_SUCCESS;
- }
+ if (!list_empty(&afs_vlocation_updates)) {
+ /* next update in 10 minutes, but wait at least 1 second more
+ * than the newest record already queued so that we don't spam
+ * the VL server suddenly with lots of requests
+ */
+ xvl = list_entry(afs_vlocation_updates.prev,
+ struct afs_vlocation, update);
+ if (vl->update_at <= xvl->update_at)
+ vl->update_at = xvl->update_at + 1;
+ xvl = list_entry(afs_vlocation_updates.next,
+ struct afs_vlocation, update);
+ timeout = xvl->update_at - now;
+ if (timeout < 0)
+ timeout = 0;
+ } else {
+ timeout = afs_vlocation_update_timeout;
}
- _leave(" = FAILED");
- return CACHEFS_MATCH_FAILED;
-}
-#endif
+ ASSERT(list_empty(&vl->update));
-/*
- * update a VLDB record stored in the cache
- */
-#ifdef AFS_CACHING_SUPPORT
-static void afs_vlocation_cache_update(void *source, void *entry)
-{
- struct afs_cache_vlocation *vldb = entry;
- struct afs_vlocation *vlocation = source;
-
- _enter("");
+ list_add_tail(&vl->update, &afs_vlocation_updates);
- *vldb = vlocation->vldb;
+ _debug("timeout %ld", timeout);
+ queue_delayed_work(afs_vlocation_update_worker,
+ &afs_vlocation_update, timeout * HZ);
+ spin_unlock(&afs_vlocation_updates_lock);
+ afs_put_vlocation(vl);
}
-#endif