[mirror_ubuntu-artful-kernel.git] / fs / afs / volume.c

/* AFS volume management
 *
 * 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
 * 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 <linux/sched.h>
#include "internal.h"

static const char *afs_voltypes[] = { "R/W", "R/O", "BAK" };

/*
 * lookup a volume by name
 * - this 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
 *	"%[cell:]volume.readonly"	R/O volume
 *	"#[cell:]volume.readonly"	R/O volume
 *	"%[cell:]volume.backup"		Backup volume
 *	"#[cell:]volume.backup"		Backup volume
 *
 * The cell name is optional, and defaults to the current cell.
 *
 * See "The Rules of Mount Point Traversal" in Chapter 5 of the AFS SysAdmin
 * Guide
 * - Rule 1: Explicit type suffix forces access of that type or nothing
 *           (no suffix, then use Rule 2 & 3)
 * - Rule 2: If parent volume is R/O, then mount R/O volume by preference, R/W
 *           if not available
 * - 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_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;
	}

	/* make the final decision on the type we want */
	ret = -ENOMEDIUM;
	if (params->force && !(vlocation->vldb.vidmask & (1 << params->type)))
		goto error;

	srvtmask = 0;
	for (loop = 0; loop < vlocation->vldb.nservers; loop++)
		srvtmask |= vlocation->vldb.srvtmask[loop];

	if (params->force) {
		if (!(srvtmask & (1 << params->type)))
			goto error;
	} else if (srvtmask & AFS_VOL_VTM_RO) {
		params->type = AFSVL_ROVOL;
	} else if (srvtmask & AFS_VOL_VTM_RW) {
		params->type = AFSVL_RWVOL;
	} else {
		goto error;
	}

	down_write(&params->cell->vl_sem);

	/* 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;
	}

	/* create a new volume record */
	_debug("creating new volume record");

	ret = -ENOMEM;
	volume = kzalloc(sizeof(struct afs_volume), GFP_KERNEL);
	if (!volume)
		goto error_up;

	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];

	volume->bdi.ra_pages	= VM_MAX_READAHEAD*1024/PAGE_SIZE; 
	ret = bdi_setup_and_register(&volume->bdi, "afs");
	if (ret)
		goto error_bdi;

	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;
			}

			volume->servers[volume->nservers] = server;
			volume->nservers++;
		}
	}

	/* attach the cache and volume location */
#ifdef CONFIG_AFS_FSCACHE
	volume->cache = fscache_acquire_cookie(vlocation->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:
	bdi_destroy(&volume->bdi);
error_bdi:
	up_write(&params->cell->vl_sem);

	for (loop = volume->nservers - 1; loop >= 0; loop--)
		afs_put_server(volume->servers[loop]);

	kfree(volume);
	goto error;
}

/*
 * destroy a volume record
 */
void afs_put_volume(struct afs_volume *volume)
{
	struct afs_vlocation *vlocation;
	int loop;

	if (!volume)
		return;

	_enter("%p", volume);

	ASSERTCMP(atomic_read(&volume->usage), >, 0);

	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);
#endif
	afs_put_vlocation(vlocation);

	for (loop = volume->nservers - 1; loop >= 0; loop--)
		afs_put_server(volume->servers[loop]);

	bdi_destroy(&volume->bdi);
	kfree(volume);

	_leave(" [destroyed]");
}

/*
 * pick a server to use to try accessing this volume
 * - returns with an elevated usage count on the server chosen
 */
struct afs_server *afs_volume_pick_fileserver(struct afs_vnode *vnode)
{
	struct afs_volume *volume = vnode->volume;
	struct afs_server *server;
	int ret, state, loop;

	_enter("%s", volume->vlocation->vldb.name);

	/* 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;
	}

	down_read(&volume->server_sem);

	/* 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);
	}

	/* basically, just search the list for the first live server and use
	 * that */
	ret = 0;
	for (loop = 0; loop < volume->nservers; loop++) {
		server = volume->servers[loop];
		state = server->fs_state;

		_debug("consider %d [%d]", loop, state);

		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;

		case -ENETUNREACH:
			if (ret == 0)
				ret = state;
			break;

		case -EHOSTUNREACH:
			if (ret == 0 ||
			    ret == -ENETUNREACH)
				ret = state;
			break;

		case -ECONNREFUSED:
			if (ret == 0 ||
			    ret == -ENETUNREACH ||
			    ret == -EHOSTUNREACH)
				ret = state;
			break;

		default:
		case -EREMOTEIO:
			if (ret == 0 ||
			    ret == -ENETUNREACH ||
			    ret == -EHOSTUNREACH ||
			    ret == -ECONNREFUSED)
				ret = state;
			break;
		}
	}

	/* no available servers
	 * - TODO: handle the no active servers case better
	 */
	up_read(&volume->server_sem);
	_leave(" = %d", ret);
	return ERR_PTR(ret);
}

/*
 * 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;
	}

	/* 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;
}
Commit	Line	Data
ec26815a	1	/* AFS volume management
1da177e4	2	*
08e0e7c8	3	* Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
1da177e4 LT	4	* Written by David Howells (dhowells@redhat.com)
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*/
	11
	12	#include <linux/kernel.h>
	13	#include <linux/module.h>
	14	#include <linux/init.h>
	15	#include <linux/slab.h>
	16	#include <linux/fs.h>
	17	#include <linux/pagemap.h>
e8edc6e0	18	#include <linux/sched.h>
1da177e4 LT	19	#include "internal.h"
1da177e4 LT	20
1da177e4	21	static const char *afs_voltypes[] = { "R/W", "R/O", "BAK" };
1da177e4	22
1da177e4 LT	23	/*
	24	* lookup a volume by name
	25	* - this can be one of the following:
	26	* "%[cell:]volume[.]" R/W volume
	27	* "#[cell:]volume[.]" R/O or R/W volume (rwparent=0),
	28	* or R/W (rwparent=1) volume
	29	* "%[cell:]volume.readonly" R/O volume
	30	* "#[cell:]volume.readonly" R/O volume
	31	* "%[cell:]volume.backup" Backup volume
	32	* "#[cell:]volume.backup" Backup volume
	33	*
	34	* The cell name is optional, and defaults to the current cell.
	35	*
	36	* See "The Rules of Mount Point Traversal" in Chapter 5 of the AFS SysAdmin
	37	* Guide
	38	* - Rule 1: Explicit type suffix forces access of that type or nothing
	39	* (no suffix, then use Rule 2 & 3)
	40	* - Rule 2: If parent volume is R/O, then mount R/O volume by preference, R/W
	41	* if not available
	42	* - Rule 3: If parent volume is R/W, then only mount R/W volume unless
	43	* explicitly told otherwise
	44	*/
00d3b7a4	45	struct afs_volume afs_volume_lookup(struct afs_mount_params params)
1da177e4 LT	46	{
	47	struct afs_vlocation *vlocation = NULL;
	48	struct afs_volume *volume = NULL;
08e0e7c8	49	struct afs_server *server = NULL;
1da177e4	50	char srvtmask;
00d3b7a4	51	int ret, loop;
1da177e4	52
00d3b7a4 DH	53	_enter("{%.s,%d}",
00d3b7a4 DH	54	params->volnamesz, params->volnamesz, params->volname, params->rwpath);
1da177e4 LT	55
1da177e4 LT	56	/* lookup the volume location record */
00d3b7a4 DH	57	vlocation = afs_vlocation_lookup(params->cell, params->key,
00d3b7a4 DH	58	params->volname, params->volnamesz);
08e0e7c8 DH	59	if (IS_ERR(vlocation)) {
	60	ret = PTR_ERR(vlocation);
	61	vlocation = NULL;
1da177e4	62	goto error;
08e0e7c8	63	}
1da177e4 LT	64
	65	/* make the final decision on the type we want */
	66	ret = -ENOMEDIUM;
00d3b7a4	67	if (params->force && !(vlocation->vldb.vidmask & (1 << params->type)))
1da177e4 LT	68	goto error;
	69
	70	srvtmask = 0;
	71	for (loop = 0; loop < vlocation->vldb.nservers; loop++)
	72	srvtmask \|= vlocation->vldb.srvtmask[loop];
	73
00d3b7a4 DH	74	if (params->force) {
00d3b7a4 DH	75	if (!(srvtmask & (1 << params->type)))
1da177e4	76	goto error;
ec26815a	77	} else if (srvtmask & AFS_VOL_VTM_RO) {
00d3b7a4	78	params->type = AFSVL_ROVOL;
ec26815a	79	} else if (srvtmask & AFS_VOL_VTM_RW) {
00d3b7a4	80	params->type = AFSVL_RWVOL;
ec26815a	81	} else {
1da177e4 LT	82	goto error;
	83	}
	84
00d3b7a4	85	down_write(&params->cell->vl_sem);
1da177e4 LT	86
1da177e4 LT	87	/* is the volume already active? */
00d3b7a4	88	if (vlocation->vols[params->type]) {
1da177e4	89	/* yes - re-use it */
00d3b7a4	90	volume = vlocation->vols[params->type];
1da177e4 LT	91	afs_get_volume(volume);
	92	goto success;
	93	}
	94
	95	/* create a new volume record */
	96	_debug("creating new volume record");
	97
	98	ret = -ENOMEM;
f8314dc6	99	volume = kzalloc(sizeof(struct afs_volume), GFP_KERNEL);
1da177e4 LT	100	if (!volume)
	101	goto error_up;
	102
1da177e4	103	atomic_set(&volume->usage, 1);
00d3b7a4 DH	104	volume->type = params->type;
	105	volume->type_force = params->force;
	106	volume->cell = params->cell;
	107	volume->vid = vlocation->vldb.vid[params->type];
1da177e4	108
91b467e0	109	volume->bdi.ra_pages = VM_MAX_READAHEAD*1024/PAGE_SIZE;
b4caecd4	110	ret = bdi_setup_and_register(&volume->bdi, "afs");
e1da0222 JA	111	if (ret)
	112	goto error_bdi;
	113
1da177e4 LT	114	init_rwsem(&volume->server_sem);
	115
	116	/* look up all the applicable server records */
	117	for (loop = 0; loop < 8; loop++) {
	118	if (vlocation->vldb.srvtmask[loop] & (1 << volume->type)) {
08e0e7c8 DH	119	server = afs_lookup_server(
	120	volume->cell, &vlocation->vldb.servers[loop]);
	121	if (IS_ERR(server)) {
	122	ret = PTR_ERR(server);
1da177e4	123	goto error_discard;
08e0e7c8	124	}
1da177e4	125
08e0e7c8	126	volume->servers[volume->nservers] = server;
1da177e4 LT	127	volume->nservers++;
	128	}
	129	}
	130
	131	/* attach the cache and volume location */
9b3f26c9 DH	132	#ifdef CONFIG_AFS_FSCACHE
	133	volume->cache = fscache_acquire_cookie(vlocation->cache,
	134	&afs_volume_cache_index_def,
94d30ae9	135	volume, true);
1da177e4	136	#endif
1da177e4 LT	137	afs_get_vlocation(vlocation);
	138	volume->vlocation = vlocation;
	139
00d3b7a4	140	vlocation->vols[volume->type] = volume;
1da177e4	141
ec26815a	142	success:
1da177e4 LT	143	_debug("kAFS selected %s volume %08x",
1da177e4 LT	144	afs_voltypes[volume->type], volume->vid);
00d3b7a4	145	up_write(&params->cell->vl_sem);
08e0e7c8	146	afs_put_vlocation(vlocation);
08e0e7c8 DH	147	_leave(" = %p", volume);
08e0e7c8 DH	148	return volume;
1da177e4 LT	149
1da177e4 LT	150	/* clean up */
ec26815a	151	error_up:
00d3b7a4	152	up_write(&params->cell->vl_sem);
ec26815a	153	error:
1da177e4	154	afs_put_vlocation(vlocation);
08e0e7c8 DH	155	_leave(" = %d", ret);
08e0e7c8 DH	156	return ERR_PTR(ret);
1da177e4	157
ec26815a	158	error_discard:
e1da0222 JA	159	bdi_destroy(&volume->bdi);
e1da0222 JA	160	error_bdi:
00d3b7a4	161	up_write(&params->cell->vl_sem);
1da177e4 LT	162
	163	for (loop = volume->nservers - 1; loop >= 0; loop--)
	164	afs_put_server(volume->servers[loop]);
	165
	166	kfree(volume);
	167	goto error;
ec26815a	168	}
1da177e4	169
1da177e4 LT	170	/*
	171	* destroy a volume record
	172	*/
	173	void afs_put_volume(struct afs_volume *volume)
	174	{
	175	struct afs_vlocation *vlocation;
	176	int loop;
	177
	178	if (!volume)
	179	return;
	180
	181	_enter("%p", volume);
	182
08e0e7c8	183	ASSERTCMP(atomic_read(&volume->usage), >, 0);
1da177e4	184
08e0e7c8	185	vlocation = volume->vlocation;
1da177e4 LT	186
	187	/* to prevent a race, the decrement and the dequeue must be effectively
	188	* atomic */
	189	down_write(&vlocation->cell->vl_sem);
	190
	191	if (likely(!atomic_dec_and_test(&volume->usage))) {
	192	up_write(&vlocation->cell->vl_sem);
	193	_leave("");
	194	return;
	195	}
	196
	197	vlocation->vols[volume->type] = NULL;
	198
	199	up_write(&vlocation->cell->vl_sem);
	200
	201	/* finish cleaning up the volume */
9b3f26c9 DH	202	#ifdef CONFIG_AFS_FSCACHE
9b3f26c9 DH	203	fscache_relinquish_cookie(volume->cache, 0);
1da177e4 LT	204	#endif
	205	afs_put_vlocation(vlocation);
	206
	207	for (loop = volume->nservers - 1; loop >= 0; loop--)
	208	afs_put_server(volume->servers[loop]);
	209
e1da0222	210	bdi_destroy(&volume->bdi);
1da177e4 LT	211	kfree(volume);
	212
	213	_leave(" [destroyed]");
ec26815a	214	}
1da177e4	215
1da177e4 LT	216	/*
	217	* pick a server to use to try accessing this volume
	218	* - returns with an elevated usage count on the server chosen
	219	*/
08e0e7c8	220	struct afs_server afs_volume_pick_fileserver(struct afs_vnode vnode)
1da177e4	221	{
08e0e7c8	222	struct afs_volume *volume = vnode->volume;
1da177e4 LT	223	struct afs_server *server;
	224	int ret, state, loop;
	225
	226	_enter("%s", volume->vlocation->vldb.name);
	227
08e0e7c8 DH	228	/* stick with the server we're already using if we can */
	229	if (vnode->server && vnode->server->fs_state == 0) {
	230	afs_get_server(vnode->server);
	231	_leave(" = %p [current]", vnode->server);
	232	return vnode->server;
	233	}
	234
1da177e4 LT	235	down_read(&volume->server_sem);
	236
	237	/* handle the no-server case */
	238	if (volume->nservers == 0) {
	239	ret = volume->rjservers ? -ENOMEDIUM : -ESTALE;
	240	up_read(&volume->server_sem);
	241	_leave(" = %d [no servers]", ret);
08e0e7c8	242	return ERR_PTR(ret);
1da177e4 LT	243	}
	244
	245	/* basically, just search the list for the first live server and use
	246	* that */
	247	ret = 0;
	248	for (loop = 0; loop < volume->nservers; loop++) {
	249	server = volume->servers[loop];
	250	state = server->fs_state;
	251
08e0e7c8 DH	252	_debug("consider %d [%d]", loop, state);
08e0e7c8 DH	253
1da177e4 LT	254	switch (state) {
	255	/* found an apparently healthy server */
	256	case 0:
	257	afs_get_server(server);
	258	up_read(&volume->server_sem);
08e0e7c8 DH	259	_leave(" = %p (picked %08x)",
	260	server, ntohl(server->addr.s_addr));
	261	return server;
1da177e4 LT	262
	263	case -ENETUNREACH:
	264	if (ret == 0)
	265	ret = state;
	266	break;
	267
	268	case -EHOSTUNREACH:
	269	if (ret == 0 \|\|
	270	ret == -ENETUNREACH)
	271	ret = state;
	272	break;
	273
	274	case -ECONNREFUSED:
	275	if (ret == 0 \|\|
	276	ret == -ENETUNREACH \|\|
	277	ret == -EHOSTUNREACH)
	278	ret = state;
	279	break;
	280
	281	default:
	282	case -EREMOTEIO:
	283	if (ret == 0 \|\|
	284	ret == -ENETUNREACH \|\|
	285	ret == -EHOSTUNREACH \|\|
	286	ret == -ECONNREFUSED)
	287	ret = state;
	288	break;
	289	}
	290	}
	291
	292	/* no available servers
	293	* - TODO: handle the no active servers case better
	294	*/
	295	up_read(&volume->server_sem);
	296	_leave(" = %d", ret);
08e0e7c8	297	return ERR_PTR(ret);
ec26815a	298	}
1da177e4	299
1da177e4 LT	300	/*
	301	* release a server after use
	302	* - releases the ref on the server struct that was acquired by picking
	303	* - records result of using a particular server to access a volume
	304	* - return 0 to try again, 1 if okay or to issue error
260a9803	305	* - the caller must release the server struct if result was 0
1da177e4	306	*/
08e0e7c8	307	int afs_volume_release_fileserver(struct afs_vnode *vnode,
1da177e4 LT	308	struct afs_server *server,
	309	int result)
	310	{
08e0e7c8	311	struct afs_volume *volume = vnode->volume;
1da177e4 LT	312	unsigned loop;
	313
	314	_enter("%s,%08x,%d",
	315	volume->vlocation->vldb.name, ntohl(server->addr.s_addr),
	316	result);
	317
	318	switch (result) {
	319	/* success */
	320	case 0:
	321	server->fs_act_jif = jiffies;
08e0e7c8	322	server->fs_state = 0;
260a9803 DH	323	_leave("");
260a9803 DH	324	return 1;
1da177e4 LT	325
	326	/* the fileserver denied all knowledge of the volume */
	327	case -ENOMEDIUM:
	328	server->fs_act_jif = jiffies;
	329	down_write(&volume->server_sem);
	330
08e0e7c8	331	/* firstly, find where the server is in the active list (if it
1da177e4 LT	332	* is) */
	333	for (loop = 0; loop < volume->nservers; loop++)
	334	if (volume->servers[loop] == server)
	335	goto present;
	336
	337	/* no longer there - may have been discarded by another op */
	338	goto try_next_server_upw;
	339
	340	present:
	341	volume->nservers--;
	342	memmove(&volume->servers[loop],
	343	&volume->servers[loop + 1],
	344	sizeof(volume->servers[loop]) *
	345	(volume->nservers - loop));
	346	volume->servers[volume->nservers] = NULL;
	347	afs_put_server(server);
	348	volume->rjservers++;
	349
	350	if (volume->nservers > 0)
	351	/* another server might acknowledge its existence */
	352	goto try_next_server_upw;
	353
	354	/* handle the case where all the fileservers have rejected the
	355	* volume
	356	* - TODO: try asking the fileservers for volume information
	357	* - TODO: contact the VL server again to see if the volume is
	358	* no longer registered
	359	*/
	360	up_write(&volume->server_sem);
	361	afs_put_server(server);
	362	_leave(" [completely rejected]");
	363	return 1;
	364
	365	/* problem reaching the server */
	366	case -ENETUNREACH:
	367	case -EHOSTUNREACH:
	368	case -ECONNREFUSED:
08e0e7c8	369	case -ETIME:
1da177e4 LT	370	case -ETIMEDOUT:
	371	case -EREMOTEIO:
	372	/* mark the server as dead
	373	* TODO: vary dead timeout depending on error
	374	*/
	375	spin_lock(&server->fs_lock);
	376	if (!server->fs_state) {
	377	server->fs_dead_jif = jiffies + HZ * 10;
	378	server->fs_state = result;
	379	printk("kAFS: SERVER DEAD state=%d\n", result);
	380	}
	381	spin_unlock(&server->fs_lock);
	382	goto try_next_server;
	383
	384	/* miscellaneous error */
	385	default:
	386	server->fs_act_jif = jiffies;
	387	case -ENOMEM:
	388	case -ENONET:
260a9803 DH	389	/* tell the caller to accept the result */
	390	afs_put_server(server);
	391	_leave(" [local failure]");
	392	return 1;
1da177e4 LT	393	}
1da177e4 LT	394
1da177e4	395	/* tell the caller to loop around and try the next server */
ec26815a	396	try_next_server_upw:
1da177e4	397	up_write(&volume->server_sem);
ec26815a	398	try_next_server:
1da177e4 LT	399	afs_put_server(server);
	400	_leave(" [try next server]");
	401	return 0;
ec26815a	402	}