linux/fs/afs/vlclient.c
David Howells 3bf0fb6f33 afs: Probe multiple fileservers simultaneously
Send probes to all the unprobed fileservers in a fileserver list on all
addresses simultaneously in an attempt to find out the fastest route whilst
not getting stuck for 20s on any server or address that we don't get a
reply from.

This alleviates the problem whereby attempting to access a new server can
take a long time because the rotation algorithm ends up rotating through
all servers and addresses until it finds one that responds.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:41:09 +01:00

652 lines
16 KiB
C

/* AFS Volume Location Service client
*
* 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/gfp.h>
#include <linux/init.h>
#include <linux/sched.h>
#include "afs_fs.h"
#include "internal.h"
/*
* Deliver reply data to a VL.GetEntryByNameU call.
*/
static int afs_deliver_vl_get_entry_by_name_u(struct afs_call *call)
{
struct afs_uvldbentry__xdr *uvldb;
struct afs_vldb_entry *entry;
bool new_only = false;
u32 tmp, nr_servers, vlflags;
int i, ret;
_enter("");
ret = afs_transfer_reply(call);
if (ret < 0)
return ret;
/* unmarshall the reply once we've received all of it */
uvldb = call->buffer;
entry = call->reply[0];
nr_servers = ntohl(uvldb->nServers);
if (nr_servers > AFS_NMAXNSERVERS)
nr_servers = AFS_NMAXNSERVERS;
for (i = 0; i < ARRAY_SIZE(uvldb->name) - 1; i++)
entry->name[i] = (u8)ntohl(uvldb->name[i]);
entry->name[i] = 0;
entry->name_len = strlen(entry->name);
/* If there is a new replication site that we can use, ignore all the
* sites that aren't marked as new.
*/
for (i = 0; i < nr_servers; i++) {
tmp = ntohl(uvldb->serverFlags[i]);
if (!(tmp & AFS_VLSF_DONTUSE) &&
(tmp & AFS_VLSF_NEWREPSITE))
new_only = true;
}
vlflags = ntohl(uvldb->flags);
for (i = 0; i < nr_servers; i++) {
struct afs_uuid__xdr *xdr;
struct afs_uuid *uuid;
int j;
tmp = ntohl(uvldb->serverFlags[i]);
if (tmp & AFS_VLSF_DONTUSE ||
(new_only && !(tmp & AFS_VLSF_NEWREPSITE)))
continue;
if (tmp & AFS_VLSF_RWVOL) {
entry->fs_mask[i] |= AFS_VOL_VTM_RW;
if (vlflags & AFS_VLF_BACKEXISTS)
entry->fs_mask[i] |= AFS_VOL_VTM_BAK;
}
if (tmp & AFS_VLSF_ROVOL)
entry->fs_mask[i] |= AFS_VOL_VTM_RO;
if (!entry->fs_mask[i])
continue;
xdr = &uvldb->serverNumber[i];
uuid = (struct afs_uuid *)&entry->fs_server[i];
uuid->time_low = xdr->time_low;
uuid->time_mid = htons(ntohl(xdr->time_mid));
uuid->time_hi_and_version = htons(ntohl(xdr->time_hi_and_version));
uuid->clock_seq_hi_and_reserved = (u8)ntohl(xdr->clock_seq_hi_and_reserved);
uuid->clock_seq_low = (u8)ntohl(xdr->clock_seq_low);
for (j = 0; j < 6; j++)
uuid->node[j] = (u8)ntohl(xdr->node[j]);
entry->nr_servers++;
}
for (i = 0; i < AFS_MAXTYPES; i++)
entry->vid[i] = ntohl(uvldb->volumeId[i]);
if (vlflags & AFS_VLF_RWEXISTS)
__set_bit(AFS_VLDB_HAS_RW, &entry->flags);
if (vlflags & AFS_VLF_ROEXISTS)
__set_bit(AFS_VLDB_HAS_RO, &entry->flags);
if (vlflags & AFS_VLF_BACKEXISTS)
__set_bit(AFS_VLDB_HAS_BAK, &entry->flags);
if (!(vlflags & (AFS_VLF_RWEXISTS | AFS_VLF_ROEXISTS | AFS_VLF_BACKEXISTS))) {
entry->error = -ENOMEDIUM;
__set_bit(AFS_VLDB_QUERY_ERROR, &entry->flags);
}
__set_bit(AFS_VLDB_QUERY_VALID, &entry->flags);
_leave(" = 0 [done]");
return 0;
}
static void afs_destroy_vl_get_entry_by_name_u(struct afs_call *call)
{
kfree(call->reply[0]);
afs_flat_call_destructor(call);
}
/*
* VL.GetEntryByNameU operation type.
*/
static const struct afs_call_type afs_RXVLGetEntryByNameU = {
.name = "VL.GetEntryByNameU",
.op = afs_VL_GetEntryByNameU,
.deliver = afs_deliver_vl_get_entry_by_name_u,
.destructor = afs_destroy_vl_get_entry_by_name_u,
};
/*
* Dispatch a get volume entry by name or ID operation (uuid variant). If the
* volname is a decimal number then it's a volume ID not a volume name.
*/
struct afs_vldb_entry *afs_vl_get_entry_by_name_u(struct afs_vl_cursor *vc,
const char *volname,
int volnamesz)
{
struct afs_vldb_entry *entry;
struct afs_call *call;
struct afs_net *net = vc->cell->net;
size_t reqsz, padsz;
__be32 *bp;
_enter("");
padsz = (4 - (volnamesz & 3)) & 3;
reqsz = 8 + volnamesz + padsz;
entry = kzalloc(sizeof(struct afs_vldb_entry), GFP_KERNEL);
if (!entry)
return ERR_PTR(-ENOMEM);
call = afs_alloc_flat_call(net, &afs_RXVLGetEntryByNameU, reqsz,
sizeof(struct afs_uvldbentry__xdr));
if (!call) {
kfree(entry);
return ERR_PTR(-ENOMEM);
}
call->key = vc->key;
call->reply[0] = entry;
call->ret_reply0 = true;
/* Marshall the parameters */
bp = call->request;
*bp++ = htonl(VLGETENTRYBYNAMEU);
*bp++ = htonl(volnamesz);
memcpy(bp, volname, volnamesz);
if (padsz > 0)
memset((void *)bp + volnamesz, 0, padsz);
trace_afs_make_vl_call(call);
return (struct afs_vldb_entry *)afs_make_call(&vc->ac, call, GFP_KERNEL, false);
}
/*
* Deliver reply data to a VL.GetAddrsU call.
*
* GetAddrsU(IN ListAddrByAttributes *inaddr,
* OUT afsUUID *uuidp1,
* OUT uint32_t *uniquifier,
* OUT uint32_t *nentries,
* OUT bulkaddrs *blkaddrs);
*/
static int afs_deliver_vl_get_addrs_u(struct afs_call *call)
{
struct afs_addr_list *alist;
__be32 *bp;
u32 uniquifier, nentries, count;
int i, ret;
_enter("{%u,%zu/%u}",
call->unmarshall, iov_iter_count(call->_iter), call->count);
switch (call->unmarshall) {
case 0:
afs_extract_to_buf(call,
sizeof(struct afs_uuid__xdr) + 3 * sizeof(__be32));
call->unmarshall++;
/* Extract the returned uuid, uniquifier, nentries and blkaddrs size */
case 1:
ret = afs_extract_data(call, true);
if (ret < 0)
return ret;
bp = call->buffer + sizeof(struct afs_uuid__xdr);
uniquifier = ntohl(*bp++);
nentries = ntohl(*bp++);
count = ntohl(*bp);
nentries = min(nentries, count);
alist = afs_alloc_addrlist(nentries, FS_SERVICE, AFS_FS_PORT);
if (!alist)
return -ENOMEM;
alist->version = uniquifier;
call->reply[0] = alist;
call->count = count;
call->count2 = nentries;
call->unmarshall++;
more_entries:
count = min(call->count, 4U);
afs_extract_to_buf(call, count * sizeof(__be32));
/* Extract entries */
case 2:
ret = afs_extract_data(call, call->count > 4);
if (ret < 0)
return ret;
alist = call->reply[0];
bp = call->buffer;
count = min(call->count, 4U);
for (i = 0; i < count; i++)
if (alist->nr_addrs < call->count2)
afs_merge_fs_addr4(alist, *bp++, AFS_FS_PORT);
call->count -= count;
if (call->count > 0)
goto more_entries;
call->unmarshall++;
break;
}
_leave(" = 0 [done]");
return 0;
}
static void afs_vl_get_addrs_u_destructor(struct afs_call *call)
{
afs_put_server(call->net, (struct afs_server *)call->reply[0]);
kfree(call->reply[1]);
return afs_flat_call_destructor(call);
}
/*
* VL.GetAddrsU operation type.
*/
static const struct afs_call_type afs_RXVLGetAddrsU = {
.name = "VL.GetAddrsU",
.op = afs_VL_GetAddrsU,
.deliver = afs_deliver_vl_get_addrs_u,
.destructor = afs_vl_get_addrs_u_destructor,
};
/*
* Dispatch an operation to get the addresses for a server, where the server is
* nominated by UUID.
*/
struct afs_addr_list *afs_vl_get_addrs_u(struct afs_vl_cursor *vc,
const uuid_t *uuid)
{
struct afs_ListAddrByAttributes__xdr *r;
const struct afs_uuid *u = (const struct afs_uuid *)uuid;
struct afs_call *call;
struct afs_net *net = vc->cell->net;
__be32 *bp;
int i;
_enter("");
call = afs_alloc_flat_call(net, &afs_RXVLGetAddrsU,
sizeof(__be32) + sizeof(struct afs_ListAddrByAttributes__xdr),
sizeof(struct afs_uuid__xdr) + 3 * sizeof(__be32));
if (!call)
return ERR_PTR(-ENOMEM);
call->key = vc->key;
call->reply[0] = NULL;
call->ret_reply0 = true;
/* Marshall the parameters */
bp = call->request;
*bp++ = htonl(VLGETADDRSU);
r = (struct afs_ListAddrByAttributes__xdr *)bp;
r->Mask = htonl(AFS_VLADDR_UUID);
r->ipaddr = 0;
r->index = 0;
r->spare = 0;
r->uuid.time_low = u->time_low;
r->uuid.time_mid = htonl(ntohs(u->time_mid));
r->uuid.time_hi_and_version = htonl(ntohs(u->time_hi_and_version));
r->uuid.clock_seq_hi_and_reserved = htonl(u->clock_seq_hi_and_reserved);
r->uuid.clock_seq_low = htonl(u->clock_seq_low);
for (i = 0; i < 6; i++)
r->uuid.node[i] = htonl(u->node[i]);
trace_afs_make_vl_call(call);
return (struct afs_addr_list *)afs_make_call(&vc->ac, call, GFP_KERNEL, false);
}
/*
* Deliver reply data to an VL.GetCapabilities operation.
*/
static int afs_deliver_vl_get_capabilities(struct afs_call *call)
{
u32 count;
int ret;
_enter("{%u,%zu/%u}",
call->unmarshall, iov_iter_count(call->_iter), call->count);
switch (call->unmarshall) {
case 0:
afs_extract_to_tmp(call);
call->unmarshall++;
/* Extract the capabilities word count */
case 1:
ret = afs_extract_data(call, true);
if (ret < 0)
return ret;
count = ntohl(call->tmp);
call->count = count;
call->count2 = count;
call->unmarshall++;
afs_extract_discard(call, count * sizeof(__be32));
/* Extract capabilities words */
case 2:
ret = afs_extract_data(call, false);
if (ret < 0)
return ret;
/* TODO: Examine capabilities */
call->unmarshall++;
break;
}
_leave(" = 0 [done]");
return 0;
}
static void afs_destroy_vl_get_capabilities(struct afs_call *call)
{
struct afs_vlserver *server = call->reply[0];
afs_put_vlserver(call->net, server);
afs_flat_call_destructor(call);
}
/*
* VL.GetCapabilities operation type
*/
static const struct afs_call_type afs_RXVLGetCapabilities = {
.name = "VL.GetCapabilities",
.op = afs_VL_GetCapabilities,
.deliver = afs_deliver_vl_get_capabilities,
.done = afs_vlserver_probe_result,
.destructor = afs_destroy_vl_get_capabilities,
};
/*
* Probe a volume server for the capabilities that it supports. This can
* return up to 196 words.
*
* We use this to probe for service upgrade to determine what the server at the
* other end supports.
*/
int afs_vl_get_capabilities(struct afs_net *net,
struct afs_addr_cursor *ac,
struct key *key,
struct afs_vlserver *server,
unsigned int server_index,
bool async)
{
struct afs_call *call;
__be32 *bp;
_enter("");
call = afs_alloc_flat_call(net, &afs_RXVLGetCapabilities, 1 * 4, 16 * 4);
if (!call)
return -ENOMEM;
call->key = key;
call->reply[0] = afs_get_vlserver(server);
call->reply[1] = (void *)(long)server_index;
call->upgrade = true;
call->want_reply_time = true;
/* marshall the parameters */
bp = call->request;
*bp++ = htonl(VLGETCAPABILITIES);
/* Can't take a ref on server */
trace_afs_make_vl_call(call);
return afs_make_call(ac, call, GFP_KERNEL, async);
}
/*
* Deliver reply data to a YFSVL.GetEndpoints call.
*
* GetEndpoints(IN yfsServerAttributes *attr,
* OUT opr_uuid *uuid,
* OUT afs_int32 *uniquifier,
* OUT endpoints *fsEndpoints,
* OUT endpoints *volEndpoints)
*/
static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
{
struct afs_addr_list *alist;
__be32 *bp;
u32 uniquifier, size;
int ret;
_enter("{%u,%zu,%u}",
call->unmarshall, iov_iter_count(call->_iter), call->count2);
switch (call->unmarshall) {
case 0:
afs_extract_to_buf(call, sizeof(uuid_t) + 3 * sizeof(__be32));
call->unmarshall = 1;
/* Extract the returned uuid, uniquifier, fsEndpoints count and
* either the first fsEndpoint type or the volEndpoints
* count if there are no fsEndpoints. */
case 1:
ret = afs_extract_data(call, true);
if (ret < 0)
return ret;
bp = call->buffer + sizeof(uuid_t);
uniquifier = ntohl(*bp++);
call->count = ntohl(*bp++);
call->count2 = ntohl(*bp); /* Type or next count */
if (call->count > YFS_MAXENDPOINTS)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_fsendpt_num);
alist = afs_alloc_addrlist(call->count, FS_SERVICE, AFS_FS_PORT);
if (!alist)
return -ENOMEM;
alist->version = uniquifier;
call->reply[0] = alist;
if (call->count == 0)
goto extract_volendpoints;
next_fsendpoint:
switch (call->count2) {
case YFS_ENDPOINT_IPV4:
size = sizeof(__be32) * (1 + 1 + 1);
break;
case YFS_ENDPOINT_IPV6:
size = sizeof(__be32) * (1 + 4 + 1);
break;
default:
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_fsendpt_type);
}
size += sizeof(__be32);
afs_extract_to_buf(call, size);
call->unmarshall = 2;
/* Extract fsEndpoints[] entries */
case 2:
ret = afs_extract_data(call, true);
if (ret < 0)
return ret;
alist = call->reply[0];
bp = call->buffer;
switch (call->count2) {
case YFS_ENDPOINT_IPV4:
if (ntohl(bp[0]) != sizeof(__be32) * 2)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_fsendpt4_len);
afs_merge_fs_addr4(alist, bp[1], ntohl(bp[2]));
bp += 3;
break;
case YFS_ENDPOINT_IPV6:
if (ntohl(bp[0]) != sizeof(__be32) * 5)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_fsendpt6_len);
afs_merge_fs_addr6(alist, bp + 1, ntohl(bp[5]));
bp += 6;
break;
default:
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_fsendpt_type);
}
/* Got either the type of the next entry or the count of
* volEndpoints if no more fsEndpoints.
*/
call->count2 = ntohl(*bp++);
call->count--;
if (call->count > 0)
goto next_fsendpoint;
extract_volendpoints:
/* Extract the list of volEndpoints. */
call->count = call->count2;
if (!call->count)
goto end;
if (call->count > YFS_MAXENDPOINTS)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_vlendpt_type);
afs_extract_to_buf(call, 1 * sizeof(__be32));
call->unmarshall = 3;
/* Extract the type of volEndpoints[0]. Normally we would
* extract the type of the next endpoint when we extract the
* data of the current one, but this is the first...
*/
case 3:
ret = afs_extract_data(call, true);
if (ret < 0)
return ret;
bp = call->buffer;
next_volendpoint:
call->count2 = ntohl(*bp++);
switch (call->count2) {
case YFS_ENDPOINT_IPV4:
size = sizeof(__be32) * (1 + 1 + 1);
break;
case YFS_ENDPOINT_IPV6:
size = sizeof(__be32) * (1 + 4 + 1);
break;
default:
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_vlendpt_type);
}
if (call->count > 1)
size += sizeof(__be32); /* Get next type too */
afs_extract_to_buf(call, size);
call->unmarshall = 4;
/* Extract volEndpoints[] entries */
case 4:
ret = afs_extract_data(call, true);
if (ret < 0)
return ret;
bp = call->buffer;
switch (call->count2) {
case YFS_ENDPOINT_IPV4:
if (ntohl(bp[0]) != sizeof(__be32) * 2)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_vlendpt4_len);
bp += 3;
break;
case YFS_ENDPOINT_IPV6:
if (ntohl(bp[0]) != sizeof(__be32) * 5)
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_vlendpt6_len);
bp += 6;
break;
default:
return afs_protocol_error(call, -EBADMSG,
afs_eproto_yvl_vlendpt_type);
}
/* Got either the type of the next entry or the count of
* volEndpoints if no more fsEndpoints.
*/
call->count--;
if (call->count > 0)
goto next_volendpoint;
end:
afs_extract_discard(call, 0);
call->unmarshall = 5;
/* Done */
case 5:
ret = afs_extract_data(call, false);
if (ret < 0)
return ret;
call->unmarshall = 6;
case 6:
break;
}
alist = call->reply[0];
_leave(" = 0 [done]");
return 0;
}
/*
* YFSVL.GetEndpoints operation type.
*/
static const struct afs_call_type afs_YFSVLGetEndpoints = {
.name = "YFSVL.GetEndpoints",
.op = afs_YFSVL_GetEndpoints,
.deliver = afs_deliver_yfsvl_get_endpoints,
.destructor = afs_vl_get_addrs_u_destructor,
};
/*
* Dispatch an operation to get the addresses for a server, where the server is
* nominated by UUID.
*/
struct afs_addr_list *afs_yfsvl_get_endpoints(struct afs_vl_cursor *vc,
const uuid_t *uuid)
{
struct afs_call *call;
struct afs_net *net = vc->cell->net;
__be32 *bp;
_enter("");
call = afs_alloc_flat_call(net, &afs_YFSVLGetEndpoints,
sizeof(__be32) * 2 + sizeof(*uuid),
sizeof(struct in6_addr) + sizeof(__be32) * 3);
if (!call)
return ERR_PTR(-ENOMEM);
call->key = vc->key;
call->reply[0] = NULL;
call->ret_reply0 = true;
/* Marshall the parameters */
bp = call->request;
*bp++ = htonl(YVLGETENDPOINTS);
*bp++ = htonl(YFS_SERVER_UUID);
memcpy(bp, uuid, sizeof(*uuid)); /* Type opr_uuid */
trace_afs_make_vl_call(call);
return (struct afs_addr_list *)afs_make_call(&vc->ac, call, GFP_KERNEL, false);
}