mirror of
https://github.com/FEX-Emu/linux.git
synced 2024-12-24 02:18:54 +00:00
1da177e4c3
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!
570 lines
13 KiB
C
570 lines
13 KiB
C
/* cell.c: AFS cell and server record 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/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 "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 DEFINE_RWLOCK(afs_cells_lock);
|
|
static DECLARE_RWSEM(afs_cells_sem); /* add/remove serialisation */
|
|
static struct afs_cell *afs_cell_root;
|
|
|
|
#ifdef AFS_CACHING_SUPPORT
|
|
static cachefs_match_val_t afs_cell_cache_match(void *target,
|
|
const void *entry);
|
|
static void afs_cell_cache_update(void *source, void *entry);
|
|
|
|
struct cachefs_index_def afs_cache_cell_index_def = {
|
|
.name = "cell_ix",
|
|
.data_size = sizeof(struct afs_cache_cell),
|
|
.keys[0] = { CACHEFS_INDEX_KEYS_ASCIIZ, 64 },
|
|
.match = afs_cell_cache_match,
|
|
.update = afs_cell_cache_update,
|
|
};
|
|
#endif
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* create a cell record
|
|
* - "name" is the name of the cell
|
|
* - "vllist" is a colon separated list of IP addresses in "a.b.c.d" format
|
|
*/
|
|
int afs_cell_create(const char *name, char *vllist, struct afs_cell **_cell)
|
|
{
|
|
struct afs_cell *cell;
|
|
char *next;
|
|
int ret;
|
|
|
|
_enter("%s", name);
|
|
|
|
BUG_ON(!name); /* TODO: want to look up "this cell" in the cache */
|
|
|
|
/* allocate and initialise a cell record */
|
|
cell = kmalloc(sizeof(struct afs_cell) + strlen(name) + 1, GFP_KERNEL);
|
|
if (!cell) {
|
|
_leave(" = -ENOMEM");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
down_write(&afs_cells_sem);
|
|
|
|
memset(cell, 0, sizeof(struct afs_cell));
|
|
atomic_set(&cell->usage, 0);
|
|
|
|
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);
|
|
|
|
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);
|
|
|
|
/* fill in the VL server list from the rest of the string */
|
|
ret = -EINVAL;
|
|
do {
|
|
unsigned a, b, c, d;
|
|
|
|
next = strchr(vllist, ':');
|
|
if (next)
|
|
*next++ = 0;
|
|
|
|
if (sscanf(vllist, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
|
|
goto badaddr;
|
|
|
|
if (a > 255 || b > 255 || c > 255 || d > 255)
|
|
goto badaddr;
|
|
|
|
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(vllist = next, vllist);
|
|
|
|
/* add a proc dir 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);
|
|
#endif
|
|
|
|
/* add to the cell lists */
|
|
write_lock(&afs_cells_lock);
|
|
list_add_tail(&cell->link, &afs_cells);
|
|
write_unlock(&afs_cells_lock);
|
|
|
|
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;
|
|
|
|
badaddr:
|
|
printk(KERN_ERR "kAFS: bad VL server IP address: '%s'\n", vllist);
|
|
error:
|
|
up_write(&afs_cells_sem);
|
|
kfree(cell);
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
} /* end afs_cell_create() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* initialise the cell database from module parameters
|
|
*/
|
|
int afs_cell_init(char *rootcell)
|
|
{
|
|
struct afs_cell *old_root, *new_root;
|
|
char *cp;
|
|
int ret;
|
|
|
|
_enter("");
|
|
|
|
if (!rootcell) {
|
|
/* module is loaded with no parameters, or built statically.
|
|
* - in the future we might initialize cell DB here.
|
|
*/
|
|
_leave(" = 0 (but 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);
|
|
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;
|
|
}
|
|
|
|
/* as afs_put_cell() takes locks by itself, we have to do
|
|
* a little gymnastics to be race-free.
|
|
*/
|
|
afs_get_cell(new_root);
|
|
|
|
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);
|
|
}
|
|
afs_cell_root = new_root;
|
|
write_unlock(&afs_cells_lock);
|
|
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
|
|
} /* end afs_cell_init() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* lookup a cell record
|
|
*/
|
|
int afs_cell_lookup(const char *name, unsigned namesz, struct afs_cell **_cell)
|
|
{
|
|
struct afs_cell *cell;
|
|
int ret;
|
|
|
|
_enter("\"%*.*s\",", namesz, namesz, name ? name : "");
|
|
|
|
*_cell = NULL;
|
|
|
|
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;
|
|
found:
|
|
|
|
read_unlock(&afs_cells_lock);
|
|
|
|
if (cell)
|
|
ret = 0;
|
|
}
|
|
else {
|
|
read_lock(&afs_cells_lock);
|
|
|
|
cell = afs_cell_root;
|
|
if (!cell) {
|
|
/* this should not happen unless user tries to mount
|
|
* when root cell is not set. Return an impossibly
|
|
* bizzare errno to alert the user. Things like
|
|
* ENOENT might be "more appropriate" but they happen
|
|
* for other reasons.
|
|
*/
|
|
ret = -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() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* try and get a cell record
|
|
*/
|
|
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() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* destroy a cell record
|
|
*/
|
|
void afs_put_cell(struct afs_cell *cell)
|
|
{
|
|
if (!cell)
|
|
return;
|
|
|
|
_enter("%p{%d,%s}", cell, atomic_read(&cell->usage), cell->name);
|
|
|
|
/* sanity check */
|
|
BUG_ON(atomic_read(&cell->usage) <= 0);
|
|
|
|
/* to prevent a race, the decrement and the dequeue must be effectively
|
|
* atomic */
|
|
write_lock(&afs_cells_lock);
|
|
|
|
if (likely(!atomic_dec_and_test(&cell->usage))) {
|
|
write_unlock(&afs_cells_lock);
|
|
_leave("");
|
|
return;
|
|
}
|
|
|
|
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));
|
|
|
|
_leave(" [unused]");
|
|
} /* end afs_put_cell() */
|
|
|
|
/*****************************************************************************/
|
|
/*
|
|
* destroy a cell record
|
|
*/
|
|
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);
|
|
|
|
/* sanity check */
|
|
BUG_ON(atomic_read(&cell->usage) != 0);
|
|
|
|
list_del_init(&cell->link);
|
|
|
|
write_unlock(&afs_cells_lock);
|
|
|
|
down_write(&afs_cells_sem);
|
|
|
|
afs_proc_cell_remove(cell);
|
|
|
|
down_write(&afs_proc_cells_sem);
|
|
list_del_init(&cell->proc_link);
|
|
up_write(&afs_proc_cells_sem);
|
|
|
|
#ifdef AFS_CACHING_SUPPORT
|
|
cachefs_relinquish_cookie(cell->cache, 0);
|
|
#endif
|
|
|
|
up_write(&afs_cells_sem);
|
|
|
|
BUG_ON(!list_empty(&cell->sv_list));
|
|
BUG_ON(!list_empty(&cell->sv_graveyard));
|
|
BUG_ON(!list_empty(&cell->vl_list));
|
|
BUG_ON(!list_empty(&cell->vl_graveyard));
|
|
|
|
/* finish cleaning up the cell */
|
|
kfree(cell);
|
|
|
|
_leave(" [destroyed]");
|
|
} /* 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);
|
|
|
|
while (!list_empty(&afs_cells)) {
|
|
cell = NULL;
|
|
|
|
/* remove the next cell from the front of the list */
|
|
write_lock(&afs_cells_lock);
|
|
|
|
if (!list_empty(&afs_cells)) {
|
|
cell = list_entry(afs_cells.next,
|
|
struct afs_cell, link);
|
|
list_del_init(&cell->link);
|
|
}
|
|
|
|
write_unlock(&afs_cells_lock);
|
|
|
|
if (cell) {
|
|
_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);
|
|
}
|
|
}
|
|
|
|
_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
|