kernel-ark/fs/afs/vlocation.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

955 lines
25 KiB
C

/* vlocation.c: volume location management
*
* Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#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
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_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
/*****************************************************************************/
/*
* 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,
struct afs_cache_vlocation *vldb)
{
struct afs_server *server = NULL;
struct afs_cell *cell = vlocation->cell;
int count, ret;
_enter("%s,%*.*s,%u", cell->name, namesz, namesz, name, namesz);
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;
}
/* attempt to access the VL server */
ret = afs_rxvl_get_entry_by_name(server, name, namesz, vldb);
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;
goto rotate;
}
/* rotate the server records upon lookup failure */
rotate:
cell->vl_curr_svix++;
cell->vl_curr_svix %= cell->vl_naddrs;
}
out:
_leave(" = %d", ret);
return ret;
} /* end afs_vlocation_access_vl_by_name() */
/*****************************************************************************/
/*
* 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,
afs_volid_t volid,
afs_voltype_t voltype,
struct afs_cache_vlocation *vldb)
{
struct afs_server *server = NULL;
struct afs_cell *cell = vlocation->cell;
int count, ret;
_enter("%s,%x,%d,", cell->name, volid, voltype);
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;
}
/* attempt to access the VL server */
ret = afs_rxvl_get_entry_by_id(server, volid, voltype, vldb);
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;
goto rotate;
}
/* rotate the server records upon lookup failure */
rotate:
cell->vl_curr_svix++;
cell->vl_curr_svix %= cell->vl_naddrs;
}
out:
_leave(" = %d", ret);
return ret;
} /* end afs_vlocation_access_vl_by_id() */
/*****************************************************************************/
/*
* 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
*/
int afs_vlocation_lookup(struct afs_cell *cell,
const char *name,
unsigned namesz,
struct afs_vlocation **_vlocation)
{
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 = kmalloc(sizeof(struct afs_vlocation), GFP_KERNEL);
if (!vlocation)
return -ENOMEM;
memset(vlocation, 0, sizeof(struct afs_vlocation));
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;
}
goto found_on_vlserver;
found_in_graveyard:
/* found in the graveyard - resurrect */
_debug("found in graveyard");
atomic_inc(&vlocation->usage);
list_del(&vlocation->link);
list_add_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);
active:
active = 1;
#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]
);
_debug("Vids: %08x %08x %08x",
vlocation->vldb.vid[0],
vlocation->vldb.vid[1],
vlocation->vldb.vid[2]);
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;
}
ret = afs_vlocation_access_vl_by_id(vlocation, 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;
/* pulled from local cache into memory */
case 0:
goto found_on_vlserver;
/* 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);
/* TODO: make existing record unavailable */
goto error;
}
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]);
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);
memcpy(&vlocation->vldb, &vldb, sizeof(vlocation->vldb));
afs_kafstimod_add_timer(&vlocation->upd_timer, 10 * HZ);
#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);
#endif
afs_put_cell(vlocation->cell);
kfree(vlocation);
}
}
_leave(" = %d", ret);
return ret;
} /* end afs_vlocation_lookup() */
/*****************************************************************************/
/*
* finish using a volume location record
* - caller must have cell->vol_sem write-locked
*/
static void __afs_put_vlocation(struct afs_vlocation *vlocation)
{
struct afs_cell *cell;
if (!vlocation)
return;
_enter("%s", vlocation->vldb.name);
cell = vlocation->cell;
/* sanity check */
BUG_ON(atomic_read(&vlocation->usage) <= 0);
spin_lock(&cell->vl_gylock);
if (likely(!atomic_dec_and_test(&vlocation->usage))) {
spin_unlock(&cell->vl_gylock);
_leave("");
return;
}
/* move to graveyard queue */
list_del(&vlocation->link);
list_add_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]");
} /* end __afs_put_vlocation() */
/*****************************************************************************/
/*
* finish using a volume location record
*/
void afs_put_vlocation(struct afs_vlocation *vlocation)
{
if (vlocation) {
struct afs_cell *cell = vlocation->cell;
down_write(&cell->vl_sem);
__afs_put_vlocation(vlocation);
up_write(&cell->vl_sem);
}
} /* end afs_put_vlocation() */
/*****************************************************************************/
/*
* timeout vlocation record
* - removes from the cell's graveyard if the usage count is zero
*/
void afs_vlocation_do_timeout(struct afs_vlocation *vlocation)
{
struct afs_cell *cell;
_enter("%s", vlocation->vldb.name);
cell = vlocation->cell;
BUG_ON(atomic_read(&vlocation->usage) < 0);
/* 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 (!vlocation) {
_leave("");
return; /* resurrected */
}
/* we can now destroy it properly */
#ifdef AFS_CACHING_SUPPORT
cachefs_relinquish_cookie(vlocation->cache, 0);
#endif
afs_put_cell(cell);
kfree(vlocation);
_leave(" [destroyed]");
} /* end afs_vlocation_do_timeout() */
/*****************************************************************************/
/*
* 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;
_enter("%s{ufs=%u ucs=%u}",
vlocation->vldb.name,
vlocation->upd_first_svix,
vlocation->upd_curr_svix);
/* 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;
}
/* contact the chosen server */
ret = afs_server_lookup(
vlocation->cell,
&vlocation->cell->vl_addrs[vlocation->upd_curr_svix],
&vlocation->upd_op.server);
switch (ret) {
case 0:
break;
case -ENOMEM:
case -ENONET:
default:
_leave(" = %d", ret);
return ret;
}
/* 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;
}
_leave(" = %d", ret);
return ret;
} /* end afs_vlocation_update_begin() */
/*****************************************************************************/
/*
* abandon updating a VL record
* - does not restart the update timer
*/
static void afs_vlocation_update_abandon(struct afs_vlocation *vlocation,
afs_vlocation_upd_t state,
int ret)
{
_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;
spin_lock(&afs_vlocation_update_lock);
afs_vlocation_update = NULL;
vlocation->upd_state = state;
/* TODO: start updating next VL record on pending list */
spin_unlock(&afs_vlocation_update_lock);
_leave("");
} /* end afs_vlocation_update_abandon() */
/*****************************************************************************/
/*
* handle periodic update timeouts and busy retry timeouts
* - called from kafstimod
*/
static void afs_vlocation_update_timer(struct afs_timer *timer)
{
struct afs_vlocation *vlocation =
list_entry(timer, struct afs_vlocation, upd_timer);
int ret;
_enter("%s", vlocation->vldb.name);
/* only update if not in the graveyard (defend against putting too) */
spin_lock(&vlocation->cell->vl_gylock);
if (!atomic_read(&vlocation->usage))
goto out_unlock1;
spin_lock(&afs_vlocation_update_lock);
/* 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);
}
else {
afs_get_vlocation(vlocation);
afs_vlocation_update = vlocation;
vlocation->upd_state = AFS_VLUPD_INPROGRESS;
}
goto out_unlock2;
}
/* 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;
}
/* 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);
}
_leave("");
return;
out_unlock2:
spin_unlock(&afs_vlocation_update_lock);
out_unlock1:
spin_unlock(&vlocation->cell->vl_gylock);
_leave("");
return;
} /* end afs_vlocation_update_timer() */
/*****************************************************************************/
/*
* attend to an update operation upon which an event happened
* - called in kafsasyncd context
*/
static void afs_vlocation_update_attend(struct afs_async_op *op)
{
struct afs_cache_vlocation vldb;
struct afs_vlocation *vlocation =
list_entry(op, struct afs_vlocation, upd_op);
unsigned tmp;
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;
tmp = vlocation->cell->vl_naddrs;
if (tmp == 0)
goto abandon;
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;
/* move to the next server */
if (vlocation->upd_curr_svix != vlocation->upd_first_svix) {
afs_vlocation_update_begin(vlocation);
_leave(" [next]");
return;
}
/* 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]");
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]");
} /* end afs_vlocation_update_attend() */
/*****************************************************************************/
/*
* 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);
afs_put_server(op->server);
op->server = NULL;
afs_put_vlocation(vlocation);
_leave("");
} /* end afs_vlocation_update_discard() */
/*****************************************************************************/
/*
* 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;
}
/* need to update cache if cached info differs */
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;
}
_leave(" = UPDATE");
return CACHEFS_MATCH_SUCCESS_UPDATE;
}
else {
_leave(" = SUCCESS");
return CACHEFS_MATCH_SUCCESS;
}
}
_leave(" = FAILED");
return CACHEFS_MATCH_FAILED;
} /* end afs_vlocation_cache_match() */
#endif
/*****************************************************************************/
/*
* 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("");
*vldb = vlocation->vldb;
} /* end afs_vlocation_cache_update() */
#endif