[PATCH 24/24] afs: Probe multiple fileservers simultaneously

From: David Howells
Date: Fri Oct 19 2018 - 21:13:38 EST

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@xxxxxxxxxx>
---

fs/afs/Makefile | 4 -
fs/afs/addr_list.c | 40 ++++--
fs/afs/cmservice.c | 129 +++++++++++++++------
fs/afs/fs_probe.c | 270 ++++++++++++++++++++++++++++++++++++++++++++
fs/afs/fsclient.c | 27 +++-
fs/afs/internal.h | 98 +++++++++++++---
fs/afs/proc.c | 6 -
fs/afs/rotate.c | 174 ++++++++++++++++++----------
fs/afs/rxrpc.c | 44 ++++---
fs/afs/server.c | 109 +-----------------
fs/afs/server_list.c | 6 -
fs/afs/vl_list.c | 6 +
fs/afs/vl_probe.c | 273 ++++++++++++++++++++++++++++++++++++++++++++
fs/afs/vl_rotate.c | 159 +++++++++++++++++---------
fs/afs/vlclient.c | 35 +++---
fs/afs/volume.c | 16 ---
include/trace/events/afs.h | 4 -
17 files changed, 1050 insertions(+), 350 deletions(-)
create mode 100644 fs/afs/fs_probe.c
create mode 100644 fs/afs/vl_probe.c

diff --git a/fs/afs/Makefile b/fs/afs/Makefile
index cc942b790cff..0738e2bf5193 100644
--- a/fs/afs/Makefile
+++ b/fs/afs/Makefile
@@ -17,6 +17,7 @@ kafs-y := \
file.o \
flock.o \
fsclient.o \
+ fs_probe.o \
inode.o \
main.o \
misc.o \
@@ -29,8 +30,9 @@ kafs-y := \
super.o \
netdevices.o \
vlclient.o \
- vl_rotate.o \
vl_list.o \
+ vl_probe.o \
+ vl_rotate.o \
volume.o \
write.o \
xattr.o \
diff --git a/fs/afs/addr_list.c b/fs/afs/addr_list.c
index 1536d1d21c33..967db336d11a 100644
--- a/fs/afs/addr_list.c
+++ b/fs/afs/addr_list.c
@@ -303,6 +303,8 @@ void afs_merge_fs_addr4(struct afs_addr_list *alist, __be32 xdr, u16 port)
sizeof(alist->addrs[0]) * (alist->nr_addrs - i));

srx = &alist->addrs[i];
+ srx->srx_family = AF_RXRPC;
+ srx->transport_type = SOCK_DGRAM;
srx->transport_len = sizeof(srx->transport.sin);
srx->transport.sin.sin_family = AF_INET;
srx->transport.sin.sin_port = htons(port);
@@ -341,6 +343,8 @@ void afs_merge_fs_addr6(struct afs_addr_list *alist, __be32 *xdr, u16 port)
sizeof(alist->addrs[0]) * (alist->nr_addrs - i));

srx = &alist->addrs[i];
+ srx->srx_family = AF_RXRPC;
+ srx->transport_type = SOCK_DGRAM;
srx->transport_len = sizeof(srx->transport.sin6);
srx->transport.sin6.sin6_family = AF_INET6;
srx->transport.sin6.sin6_port = htons(port);
@@ -353,23 +357,32 @@ void afs_merge_fs_addr6(struct afs_addr_list *alist, __be32 *xdr, u16 port)
*/
bool afs_iterate_addresses(struct afs_addr_cursor *ac)
{
- _enter("%hu+%hd", ac->start, (short)ac->index);
+ unsigned long set, failed;
+ int index;

if (!ac->alist)
return false;

+ set = ac->alist->responded;
+ failed = ac->alist->failed;
+ _enter("%lx-%lx-%lx,%d", set, failed, ac->tried, ac->index);
+
ac->nr_iterations++;

- if (ac->begun) {
- ac->index++;
- if (ac->index == ac->alist->nr_addrs)
- ac->index = 0;
+ set &= ~(failed | ac->tried);

- if (ac->index == ac->start)
- return false;
- }
+ if (!set)
+ return false;
+
+ index = READ_ONCE(ac->alist->preferred);
+ if (test_bit(index, &set))
+ goto selected;
+
+ index = __ffs(set);

- ac->begun = true;
+selected:
+ ac->index = index;
+ set_bit(index, &ac->tried);
ac->responded = false;
return true;
}
@@ -383,12 +396,13 @@ int afs_end_cursor(struct afs_addr_cursor *ac)

alist = ac->alist;
if (alist) {
- if (ac->responded && ac->index != ac->start)
- WRITE_ONCE(alist->index, ac->index);
+ if (ac->responded &&
+ ac->index != alist->preferred &&
+ test_bit(ac->alist->preferred, &ac->tried))
+ WRITE_ONCE(alist->preferred, ac->index);
afs_put_addrlist(alist);
+ ac->alist = NULL;
}

- ac->alist = NULL;
- ac->begun = false;
return ac->error;
}
diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c
index 8cf8d10daa6c..8ee5972893ed 100644
--- a/fs/afs/cmservice.c
+++ b/fs/afs/cmservice.c
@@ -122,6 +122,8 @@ bool afs_cm_incoming_call(struct afs_call *call)
{
_enter("{%u, CB.OP %u}", call->service_id, call->operation_ID);

+ call->epoch = rxrpc_kernel_get_epoch(call->net->socket, call->rxcall);
+
switch (call->operation_ID) {
case CBCallBack:
call->type = &afs_SRXCBCallBack;
@@ -151,6 +153,91 @@ bool afs_cm_incoming_call(struct afs_call *call)
}
}

+/*
+ * Record a probe to the cache manager from a server.
+ */
+static int afs_record_cm_probe(struct afs_call *call, struct afs_server *server)
+{
+ _enter("");
+
+ if (test_bit(AFS_SERVER_FL_HAVE_EPOCH, &server->flags) &&
+ !test_bit(AFS_SERVER_FL_PROBING, &server->flags)) {
+ if (server->cm_epoch == call->epoch)
+ return 0;
+
+ if (!server->probe.said_rebooted) {
+ pr_notice("kAFS: FS rebooted %pU\n", &server->uuid);
+ server->probe.said_rebooted = true;
+ }
+ }
+
+ spin_lock(&server->probe_lock);
+
+ if (!test_bit(AFS_SERVER_FL_HAVE_EPOCH, &server->flags)) {
+ server->cm_epoch = call->epoch;
+ server->probe.cm_epoch = call->epoch;
+ goto out;
+ }
+
+ if (server->probe.cm_probed &&
+ call->epoch != server->probe.cm_epoch &&
+ !server->probe.said_inconsistent) {
+ pr_notice("kAFS: FS endpoints inconsistent %pU\n",
+ &server->uuid);
+ server->probe.said_inconsistent = true;
+ }
+
+ if (!server->probe.cm_probed || call->epoch == server->cm_epoch)
+ server->probe.cm_epoch = server->cm_epoch;
+
+out:
+ server->probe.cm_probed = true;
+ spin_unlock(&server->probe_lock);
+ return 0;
+}
+
+/*
+ * Find the server record by peer address and record a probe to the cache
+ * manager from a server.
+ */
+static int afs_find_cm_server_by_peer(struct afs_call *call)
+{
+ struct sockaddr_rxrpc srx;
+ struct afs_server *server;
+
+ rxrpc_kernel_get_peer(call->net->socket, call->rxcall, &srx);
+
+ server = afs_find_server(call->net, &srx);
+ if (!server) {
+ trace_afs_cm_no_server(call, &srx);
+ return 0;
+ }
+
+ call->cm_server = server;
+ return afs_record_cm_probe(call, server);
+}
+
+/*
+ * Find the server record by server UUID and record a probe to the cache
+ * manager from a server.
+ */
+static int afs_find_cm_server_by_uuid(struct afs_call *call,
+ struct afs_uuid *uuid)
+{
+ struct afs_server *server;
+
+ rcu_read_lock();
+ server = afs_find_server_by_uuid(call->net, call->request);
+ rcu_read_unlock();
+ if (!server) {
+ trace_afs_cm_no_server_u(call, call->request);
+ return 0;
+ }
+
+ call->cm_server = server;
+ return afs_record_cm_probe(call, server);
+}
+
/*
* Clean up a cache manager call.
*/
@@ -187,7 +274,6 @@ static void SRXAFSCB_CallBack(struct work_struct *work)
static int afs_deliver_cb_callback(struct afs_call *call)
{
struct afs_callback_break *cb;
- struct sockaddr_rxrpc srx;
__be32 *bp;
int ret, loop;

@@ -276,12 +362,7 @@ static int afs_deliver_cb_callback(struct afs_call *call)

/* we'll need the file server record as that tells us which set of
* vnodes to operate upon */
- rxrpc_kernel_get_peer(call->net->socket, call->rxcall, &srx);
- call->cm_server = afs_find_server(call->net, &srx);
- if (!call->cm_server)
- trace_afs_cm_no_server(call, &srx);
-
- return afs_queue_call_work(call);
+ return afs_find_cm_server_by_peer(call);
}

/*
@@ -305,13 +386,10 @@ static void SRXAFSCB_InitCallBackState(struct work_struct *work)
*/
static int afs_deliver_cb_init_call_back_state(struct afs_call *call)
{
- struct sockaddr_rxrpc srx;
int ret;

_enter("");

- rxrpc_kernel_get_peer(call->net->socket, call->rxcall, &srx);
-
afs_extract_discard(call, 0);
ret = afs_extract_data(call, false);
if (ret < 0)
@@ -319,11 +397,7 @@ static int afs_deliver_cb_init_call_back_state(struct afs_call *call)

/* we'll need the file server record as that tells us which set of
* vnodes to operate upon */
- call->cm_server = afs_find_server(call->net, &srx);
- if (!call->cm_server)
- trace_afs_cm_no_server(call, &srx);
-
- return afs_queue_call_work(call);
+ return afs_find_cm_server_by_peer(call);
}

/*
@@ -384,13 +458,7 @@ static int afs_deliver_cb_init_call_back_state3(struct afs_call *call)

/* we'll need the file server record as that tells us which set of
* vnodes to operate upon */
- rcu_read_lock();
- call->cm_server = afs_find_server_by_uuid(call->net, call->request);
- rcu_read_unlock();
- if (!call->cm_server)
- trace_afs_cm_no_server_u(call, call->request);
-
- return afs_queue_call_work(call);
+ return afs_find_cm_server_by_uuid(call, call->request);
}

/*
@@ -422,8 +490,7 @@ static int afs_deliver_cb_probe(struct afs_call *call)

if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
return afs_io_error(call, afs_io_error_cm_reply);
-
- return afs_queue_call_work(call);
+ return afs_find_cm_server_by_peer(call);
}

/*
@@ -503,8 +570,7 @@ static int afs_deliver_cb_probe_uuid(struct afs_call *call)

if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
return afs_io_error(call, afs_io_error_cm_reply);
-
- return afs_queue_call_work(call);
+ return afs_find_cm_server_by_uuid(call, call->request);
}

/*
@@ -586,8 +652,7 @@ static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)

if (!afs_check_call_state(call, AFS_CALL_SV_REPLYING))
return afs_io_error(call, afs_io_error_cm_reply);
-
- return afs_queue_call_work(call);
+ return afs_find_cm_server_by_peer(call);
}

/*
@@ -596,7 +661,6 @@ static int afs_deliver_cb_tell_me_about_yourself(struct afs_call *call)
static int afs_deliver_yfs_cb_callback(struct afs_call *call)
{
struct afs_callback_break *cb;
- struct sockaddr_rxrpc srx;
struct yfs_xdr_YFSFid *bp;
size_t size;
int ret, loop;
@@ -664,10 +728,5 @@ static int afs_deliver_yfs_cb_callback(struct afs_call *call)
/* We'll need the file server record as that tells us which set of
* vnodes to operate upon.
*/
- rxrpc_kernel_get_peer(call->net->socket, call->rxcall, &srx);
- call->cm_server = afs_find_server(call->net, &srx);
- if (!call->cm_server)
- trace_afs_cm_no_server(call, &srx);
-
- return afs_queue_call_work(call);
+ return afs_find_cm_server_by_peer(call);
}
diff --git a/fs/afs/fs_probe.c b/fs/afs/fs_probe.c
new file mode 100644
index 000000000000..d049cb459742
--- /dev/null
+++ b/fs/afs/fs_probe.c
@@ -0,0 +1,270 @@
+/* AFS fileserver probing
+ *
+ * Copyright (C) 2018 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@xxxxxxxxxx)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include "afs_fs.h"
+#include "internal.h"
+#include "protocol_yfs.h"
+
+static bool afs_fs_probe_done(struct afs_server *server)
+{
+ if (!atomic_dec_and_test(&server->probe_outstanding))
+ return false;
+
+ wake_up_var(&server->probe_outstanding);
+ clear_bit_unlock(AFS_SERVER_FL_PROBING, &server->flags);
+ wake_up_bit(&server->flags, AFS_SERVER_FL_PROBING);
+ return true;
+}
+
+/*
+ * Process the result of probing a fileserver. This is called after successful
+ * or failed delivery of an FS.GetCapabilities operation.
+ */
+void afs_fileserver_probe_result(struct afs_call *call)
+{
+ struct afs_addr_list *alist = call->alist;
+ struct afs_server *server = call->reply[0];
+ unsigned int server_index = (long)call->reply[1];
+ unsigned int index = call->addr_ix;
+ unsigned int rtt = UINT_MAX;
+ bool have_result = false;
+ u64 _rtt;
+ int ret = call->error;
+
+ _enter("%pU,%u", &server->uuid, index);
+
+ spin_lock(&server->probe_lock);
+
+ switch (ret) {
+ case 0:
+ server->probe.error = 0;
+ goto responded;
+ case -ECONNABORTED:
+ if (!server->probe.responded) {
+ server->probe.abort_code = call->abort_code;
+ server->probe.error = ret;
+ }
+ goto responded;
+ case -ENOMEM:
+ case -ENONET:
+ server->probe.local_failure = true;
+ afs_io_error(call, afs_io_error_fs_probe_fail);
+ goto out;
+ case -ECONNRESET: /* Responded, but call expired. */
+ case -ENETUNREACH:
+ case -EHOSTUNREACH:
+ case -ECONNREFUSED:
+ case -ETIMEDOUT:
+ case -ETIME:
+ default:
+ clear_bit(index, &alist->responded);
+ set_bit(index, &alist->failed);
+ if (!server->probe.responded &&
+ (server->probe.error == 0 ||
+ server->probe.error == -ETIMEDOUT ||
+ server->probe.error == -ETIME))
+ server->probe.error = ret;
+ afs_io_error(call, afs_io_error_fs_probe_fail);
+ goto out;
+ }
+
+responded:
+ set_bit(index, &alist->responded);
+ clear_bit(index, &alist->failed);
+
+ if (call->service_id == YFS_FS_SERVICE) {
+ server->probe.is_yfs = true;
+ set_bit(AFS_SERVER_FL_IS_YFS, &server->flags);
+ alist->addrs[index].srx_service = call->service_id;
+ } else {
+ server->probe.not_yfs = true;
+ if (!server->probe.is_yfs) {
+ clear_bit(AFS_SERVER_FL_IS_YFS, &server->flags);
+ alist->addrs[index].srx_service = call->service_id;
+ }
+ }
+
+ /* Get the RTT and scale it to fit into a 32-bit value that represents
+ * over a minute of time so that we can access it with one instruction
+ * on a 32-bit system.
+ */
+ _rtt = rxrpc_kernel_get_rtt(call->net->socket, call->rxcall);
+ _rtt /= 64;
+ rtt = (_rtt > UINT_MAX) ? UINT_MAX : _rtt;
+ if (rtt < server->probe.rtt) {
+ server->probe.rtt = rtt;
+ alist->preferred = index;
+ have_result = true;
+ }
+
+ smp_wmb(); /* Set rtt before responded. */
+ server->probe.responded = true;
+ set_bit(AFS_SERVER_FL_PROBED, &server->flags);
+out:
+ spin_unlock(&server->probe_lock);
+
+ _debug("probe [%u][%u] %pISpc rtt=%u ret=%d",
+ server_index, index, &alist->addrs[index].transport,
+ (unsigned int)rtt, ret);
+
+ have_result |= afs_fs_probe_done(server);
+ if (have_result) {
+ server->probe.have_result = true;
+ wake_up_var(&server->probe.have_result);
+ wake_up_all(&server->probe_wq);
+ }
+}
+
+/*
+ * Probe all of a fileserver's addresses to find out the best route and to
+ * query its capabilities.
+ */
+static int afs_do_probe_fileserver(struct afs_net *net,
+ struct afs_server *server,
+ struct key *key,
+ unsigned int server_index)
+{
+ struct afs_addr_cursor ac = {
+ .index = 0,
+ };
+ int ret;
+
+ _enter("%pU", &server->uuid);
+
+ read_lock(&server->fs_lock);
+ ac.alist = rcu_dereference_protected(server->addresses,
+ lockdep_is_held(&server->fs_lock));
+ read_unlock(&server->fs_lock);
+
+ atomic_set(&server->probe_outstanding, ac.alist->nr_addrs);
+ memset(&server->probe, 0, sizeof(server->probe));
+ server->probe.rtt = UINT_MAX;
+
+ for (ac.index = 0; ac.index < ac.alist->nr_addrs; ac.index++) {
+ ret = afs_fs_get_capabilities(net, server, &ac, key, server_index,
+ true);
+ if (ret != -EINPROGRESS) {
+ afs_fs_probe_done(server);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Send off probes to all unprobed servers.
+ */
+int afs_probe_fileservers(struct afs_net *net, struct key *key,
+ struct afs_server_list *list)
+{
+ struct afs_server *server;
+ int i, ret;
+
+ for (i = 0; i < list->nr_servers; i++) {
+ server = list->servers[i].server;
+ if (test_bit(AFS_SERVER_FL_PROBED, &server->flags))
+ continue;
+
+ if (!test_and_set_bit_lock(AFS_SERVER_FL_PROBING, &server->flags)) {
+ ret = afs_do_probe_fileserver(net, server, key, i);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Wait for the first as-yet untried fileserver to respond.
+ */
+int afs_wait_for_fs_probes(struct afs_server_list *slist, unsigned long untried)
+{
+ struct wait_queue_entry *waits;
+ struct afs_server *server;
+ unsigned int rtt = UINT_MAX;
+ bool have_responders = false;
+ int pref = -1, i;
+
+ _enter("%u,%lx", slist->nr_servers, untried);
+
+ /* Only wait for servers that have a probe outstanding. */
+ for (i = 0; i < slist->nr_servers; i++) {
+ if (test_bit(i, &untried)) {
+ server = slist->servers[i].server;
+ if (!test_bit(AFS_SERVER_FL_PROBING, &server->flags))
+ __clear_bit(i, &untried);
+ if (server->probe.responded)
+ have_responders = true;
+ }
+ }
+ if (have_responders || !untried)
+ return 0;
+
+ waits = kmalloc(array_size(slist->nr_servers, sizeof(*waits)), GFP_KERNEL);
+ if (!waits)
+ return -ENOMEM;
+
+ for (i = 0; i < slist->nr_servers; i++) {
+ if (test_bit(i, &untried)) {
+ server = slist->servers[i].server;
+ init_waitqueue_entry(&waits[i], current);
+ add_wait_queue(&server->probe_wq, &waits[i]);
+ }
+ }
+
+ for (;;) {
+ bool still_probing = false;
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ for (i = 0; i < slist->nr_servers; i++) {
+ if (test_bit(i, &untried)) {
+ server = slist->servers[i].server;
+ if (server->probe.responded)
+ goto stop;
+ if (test_bit(AFS_SERVER_FL_PROBING, &server->flags))
+ still_probing = true;
+ }
+ }
+
+ if (!still_probing || unlikely(signal_pending(current)))
+ goto stop;
+ schedule();
+ }
+
+stop:
+ set_current_state(TASK_RUNNING);
+
+ for (i = 0; i < slist->nr_servers; i++) {
+ if (test_bit(i, &untried)) {
+ server = slist->servers[i].server;
+ if (server->probe.responded &&
+ server->probe.rtt < rtt) {
+ pref = i;
+ rtt = server->probe.rtt;
+ }
+
+ remove_wait_queue(&server->probe_wq, &waits[i]);
+ }
+ }
+
+ kfree(waits);
+
+ if (pref == -1 && signal_pending(current))
+ return -ERESTARTSYS;
+
+ if (pref >= 0)
+ slist->preferred = pref;
+ return 0;
+}
diff --git a/fs/afs/fsclient.c b/fs/afs/fsclient.c
index 7c75a1813321..ca08c83168f5 100644
--- a/fs/afs/fsclient.c
+++ b/fs/afs/fsclient.c
@@ -2006,7 +2006,6 @@ int afs_fs_give_up_all_callbacks(struct afs_net *net,
*/
static int afs_deliver_fs_get_capabilities(struct afs_call *call)
{
- struct afs_server *server = call->reply[0];
u32 count;
int ret;

@@ -2042,15 +2041,18 @@ static int afs_deliver_fs_get_capabilities(struct afs_call *call)
break;
}

- if (call->service_id == YFS_FS_SERVICE)
- set_bit(AFS_SERVER_FL_IS_YFS, &server->flags);
- else
- clear_bit(AFS_SERVER_FL_IS_YFS, &server->flags);
-
_leave(" = 0 [done]");
return 0;
}

+static void afs_destroy_fs_get_capabilities(struct afs_call *call)
+{
+ struct afs_server *server = call->reply[0];
+
+ afs_put_server(call->net, server);
+ afs_flat_call_destructor(call);
+}
+
/*
* FS.GetCapabilities operation type
*/
@@ -2058,7 +2060,8 @@ static const struct afs_call_type afs_RXFSGetCapabilities = {
.name = "FS.GetCapabilities",
.op = afs_FS_GetCapabilities,
.deliver = afs_deliver_fs_get_capabilities,
- .destructor = afs_flat_call_destructor,
+ .done = afs_fileserver_probe_result,
+ .destructor = afs_destroy_fs_get_capabilities,
};

/*
@@ -2068,7 +2071,9 @@ static const struct afs_call_type afs_RXFSGetCapabilities = {
int afs_fs_get_capabilities(struct afs_net *net,
struct afs_server *server,
struct afs_addr_cursor *ac,
- struct key *key)
+ struct key *key,
+ unsigned int server_index,
+ bool async)
{
struct afs_call *call;
__be32 *bp;
@@ -2080,8 +2085,10 @@ int afs_fs_get_capabilities(struct afs_net *net,
return -ENOMEM;

call->key = key;
- call->reply[0] = server;
+ call->reply[0] = afs_get_server(server);
+ call->reply[1] = (void *)(long)server_index;
call->upgrade = true;
+ call->want_reply_time = true;

/* marshall the parameters */
bp = call->request;
@@ -2089,7 +2096,7 @@ int afs_fs_get_capabilities(struct afs_net *net,

/* Can't take a ref on server */
trace_afs_make_fs_call(call, NULL);
- return afs_make_call(ac, call, GFP_NOFS, false);
+ return afs_make_call(ac, call, GFP_NOFS, async);
}

/*
diff --git a/fs/afs/internal.h b/fs/afs/internal.h
index b60d15212975..5da3b09b7518 100644
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -76,12 +76,13 @@ struct afs_addr_list {
u32 version; /* Version */
unsigned char max_addrs;
unsigned char nr_addrs;
- unsigned char index; /* Address currently in use */
+ unsigned char preferred; /* Preferred address */
unsigned char nr_ipv4; /* Number of IPv4 addresses */
enum dns_record_source source:8;
enum dns_lookup_status status:8;
unsigned long probed; /* Mask of servers that have been probed */
- unsigned long yfs; /* Mask of servers that are YFS */
+ unsigned long failed; /* Mask of addrs that failed locally/ICMP */
+ unsigned long responded; /* Mask of addrs that responded */
struct sockaddr_rxrpc addrs[];
#define AFS_MAX_ADDRESSES ((unsigned int)(sizeof(unsigned long) * 8))
};
@@ -91,6 +92,7 @@ struct afs_addr_list {
*/
struct afs_call {
const struct afs_call_type *type; /* type of call */
+ struct afs_addr_list *alist; /* Address is alist[addr_ix] */
wait_queue_head_t waitq; /* processes awaiting completion */
struct work_struct async_work; /* async I/O processor */
struct work_struct work; /* actual work processor */
@@ -116,6 +118,7 @@ struct afs_call {
spinlock_t state_lock;
int error; /* error code */
u32 abort_code; /* Remote abort ID or 0 */
+ u32 epoch;
unsigned request_size; /* size of request data */
unsigned reply_max; /* maximum size of reply */
unsigned first_offset; /* offset into mapping[first] */
@@ -125,13 +128,14 @@ struct afs_call {
unsigned count2; /* count used in unmarshalling */
};
unsigned char unmarshall; /* unmarshalling phase */
+ unsigned char addr_ix; /* Address in ->alist */
bool incoming; /* T if incoming call */
bool send_pages; /* T if data from mapping should be sent */
bool need_attention; /* T if RxRPC poked us */
bool async; /* T if asynchronous */
bool ret_reply0; /* T if should return reply[0] on success */
bool upgrade; /* T to request service upgrade */
- bool want_reply_time; /* T if want reply_time */
+ bool want_reply_time; /* T if want reply_time */
u16 service_id; /* Actual service ID (after upgrade) */
unsigned int debug_id; /* Trace ID */
u32 operation_ID; /* operation ID for an incoming call */
@@ -162,6 +166,9 @@ struct afs_call_type {

/* Work function */
void (*work)(struct work_struct *work);
+
+ /* Call done function (gets called immediately on success or failure) */
+ void (*done)(struct afs_call *call);
};

/*
@@ -376,10 +383,27 @@ struct afs_vlserver {
unsigned long flags;
#define AFS_VLSERVER_FL_PROBED 0 /* The VL server has been probed */
#define AFS_VLSERVER_FL_PROBING 1 /* VL server is being probed */
+#define AFS_VLSERVER_FL_IS_YFS 2 /* Server is YFS not AFS */
rwlock_t lock; /* Lock on addresses */
atomic_t usage;
- u16 name_len; /* Length of name */
+
+ /* Probe state */
+ wait_queue_head_t probe_wq;
+ atomic_t probe_outstanding;
+ spinlock_t probe_lock;
+ struct {
+ unsigned int rtt; /* RTT as ktime/64 */
+ u32 abort_code;
+ short error;
+ bool have_result;
+ bool responded:1;
+ bool is_yfs:1;
+ bool not_yfs:1;
+ bool local_failure:1;
+ } probe;
+
u16 port;
+ u16 name_len; /* Length of name */
char name[]; /* Server name, case-flattened */
};

@@ -399,6 +423,7 @@ struct afs_vlserver_list {
atomic_t usage;
u8 nr_servers;
u8 index; /* Server currently in use */
+ u8 preferred; /* Preferred server */
enum dns_record_source source:8;
enum dns_lookup_status status:8;
rwlock_t lock;
@@ -461,8 +486,10 @@ struct afs_server {
#define AFS_SERVER_FL_MAY_HAVE_CB 8 /* May have callbacks on this fileserver */
#define AFS_SERVER_FL_IS_YFS 9 /* Server is YFS not AFS */
#define AFS_SERVER_FL_NO_RM2 10 /* Fileserver doesn't support YFS.RemoveFile2 */
+#define AFS_SERVER_FL_HAVE_EPOCH 11 /* ->epoch is valid */
atomic_t usage;
u32 addr_version; /* Address list version */
+ u32 cm_epoch; /* Server RxRPC epoch */

/* file service access */
rwlock_t fs_lock; /* access lock */
@@ -471,6 +498,26 @@ struct afs_server {
struct hlist_head cb_volumes; /* List of volume interests on this server */
unsigned cb_s_break; /* Break-everything counter. */
rwlock_t cb_break_lock; /* Volume finding lock */
+
+ /* Probe state */
+ wait_queue_head_t probe_wq;
+ atomic_t probe_outstanding;
+ spinlock_t probe_lock;
+ struct {
+ unsigned int rtt; /* RTT as ktime/64 */
+ u32 abort_code;
+ u32 cm_epoch;
+ short error;
+ bool have_result;
+ bool responded:1;
+ bool is_yfs:1;
+ bool not_yfs:1;
+ bool local_failure:1;
+ bool no_epoch:1;
+ bool cm_probed:1;
+ bool said_rebooted:1;
+ bool said_inconsistent:1;
+ } probe;
};

/*
@@ -505,8 +552,8 @@ struct afs_server_entry {

struct afs_server_list {
refcount_t usage;
- unsigned short nr_servers;
- unsigned short index; /* Server currently in use */
+ unsigned char nr_servers;
+ unsigned char preferred; /* Preferred server */
unsigned short vnovol_mask; /* Servers to be skipped due to VNOVOL */
unsigned int seq; /* Set to ->servers_seq when installed */
rwlock_t lock;
@@ -653,13 +700,12 @@ struct afs_interface {
*/
struct afs_addr_cursor {
struct afs_addr_list *alist; /* Current address list (pins ref) */
- u32 abort_code;
- unsigned short start; /* Starting point in alist->addrs[] */
- unsigned short index; /* Wrapping offset from start to current addr */
- short error;
- bool begun; /* T if we've begun iteration */
+ unsigned long tried; /* Tried addresses */
+ signed char index; /* Current address */
bool responded; /* T if the current address responded */
unsigned short nr_iterations; /* Number of address iterations */
+ short error;
+ u32 abort_code;
};

/*
@@ -669,9 +715,10 @@ struct afs_vl_cursor {
struct afs_addr_cursor ac;
struct afs_cell *cell; /* The cell we're querying */
struct afs_vlserver_list *server_list; /* Current server list (pins ref) */
+ struct afs_vlserver *server; /* Server on which this resides */
struct key *key; /* Key for the server */
- unsigned char start; /* Initial index in server list */
- unsigned char index; /* Number of servers tried beyond start */
+ unsigned long untried; /* Bitmask of untried servers */
+ short index; /* Current server */
short error;
unsigned short flags;
#define AFS_VL_CURSOR_STOP 0x0001 /* Set to cease iteration */
@@ -689,10 +736,10 @@ struct afs_fs_cursor {
struct afs_server_list *server_list; /* Current server list (pins ref) */
struct afs_cb_interest *cbi; /* Server on which this resides (pins ref) */
struct key *key; /* Key for the server */
+ unsigned long untried; /* Bitmask of untried servers */
unsigned int cb_break; /* cb_break + cb_s_break before the call */
unsigned int cb_break_2; /* cb_break + cb_s_break (2nd vnode) */
- unsigned char start; /* Initial index in server list */
- unsigned char index; /* Number of servers tried beyond start */
+ short index; /* Current server */
short error;
unsigned short flags;
#define AFS_FS_CURSOR_STOP 0x0001 /* Set to cease iteration */
@@ -888,7 +935,7 @@ extern int afs_fs_release_lock(struct afs_fs_cursor *);
extern int afs_fs_give_up_all_callbacks(struct afs_net *, struct afs_server *,
struct afs_addr_cursor *, struct key *);
extern int afs_fs_get_capabilities(struct afs_net *, struct afs_server *,
- struct afs_addr_cursor *, struct key *);
+ struct afs_addr_cursor *, struct key *, unsigned int, bool);
extern int afs_fs_inline_bulk_status(struct afs_fs_cursor *, struct afs_net *,
struct afs_fid *, struct afs_file_status *,
struct afs_callback *, unsigned int,
@@ -897,6 +944,13 @@ extern int afs_fs_fetch_status(struct afs_fs_cursor *, struct afs_net *,
struct afs_fid *, struct afs_file_status *,
struct afs_callback *, struct afs_volsync *);

+/*
+ * fs_probe.c
+ */
+extern void afs_fileserver_probe_result(struct afs_call *);
+extern int afs_probe_fileservers(struct afs_net *, struct key *, struct afs_server_list *);
+extern int afs_wait_for_fs_probes(struct afs_server_list *, unsigned long);
+
/*
* inode.c
*/
@@ -1013,7 +1067,6 @@ extern int __net_init afs_open_socket(struct afs_net *);
extern void __net_exit afs_close_socket(struct afs_net *);
extern void afs_charge_preallocation(struct work_struct *);
extern void afs_put_call(struct afs_call *);
-extern int afs_queue_call_work(struct afs_call *);
extern long afs_make_call(struct afs_addr_cursor *, struct afs_call *, gfp_t, bool);
extern struct afs_call *afs_alloc_flat_call(struct afs_net *,
const struct afs_call_type *,
@@ -1130,7 +1183,6 @@ extern void afs_put_server(struct afs_net *, struct afs_server *);
extern void afs_manage_servers(struct work_struct *);
extern void afs_servers_timer(struct timer_list *);
extern void __net_exit afs_purge_servers(struct afs_net *);
-extern bool afs_probe_fileserver(struct afs_fs_cursor *);
extern bool afs_check_server_record(struct afs_fs_cursor *, struct afs_server *);

/*
@@ -1160,9 +1212,17 @@ extern void afs_fs_exit(void);
extern struct afs_vldb_entry *afs_vl_get_entry_by_name_u(struct afs_vl_cursor *,
const char *, int);
extern struct afs_addr_list *afs_vl_get_addrs_u(struct afs_vl_cursor *, const uuid_t *);
-extern int afs_vl_get_capabilities(struct afs_net *, struct afs_addr_cursor *, struct key *);
+extern int afs_vl_get_capabilities(struct afs_net *, struct afs_addr_cursor *, struct key *,
+ struct afs_vlserver *, unsigned int, bool);
extern struct afs_addr_list *afs_yfsvl_get_endpoints(struct afs_vl_cursor *, const uuid_t *);

+/*
+ * vl_probe.c
+ */
+extern void afs_vlserver_probe_result(struct afs_call *);
+extern int afs_send_vl_probes(struct afs_net *, struct key *, struct afs_vlserver_list *);
+extern int afs_wait_for_vl_probes(struct afs_vlserver_list *, unsigned long);
+
/*
* vl_rotate.c
*/
diff --git a/fs/afs/proc.c b/fs/afs/proc.c
index d887f822f4eb..be2ee3bbd0a9 100644
--- a/fs/afs/proc.c
+++ b/fs/afs/proc.c
@@ -312,7 +312,7 @@ static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
if (alist) {
for (i = 0; i < alist->nr_addrs; i++)
seq_printf(m, " %c %pISpc\n",
- alist->index == i ? '>' : '-',
+ alist->preferred == i ? '>' : '-',
&alist->addrs[i].transport);
}
return 0;
@@ -391,11 +391,11 @@ static int afs_proc_servers_show(struct seq_file *m, void *v)
&server->uuid,
atomic_read(&server->usage),
&alist->addrs[0].transport,
- alist->index == 0 ? "*" : "");
+ alist->preferred == 0 ? "*" : "");
for (i = 1; i < alist->nr_addrs; i++)
seq_printf(m, " %pISpc%s\n",
&alist->addrs[i].transport,
- alist->index == i ? "*" : "");
+ alist->preferred == i ? "*" : "");
return 0;
}

diff --git a/fs/afs/rotate.c b/fs/afs/rotate.c
index 7c4487781637..00504254c1c2 100644
--- a/fs/afs/rotate.c
+++ b/fs/afs/rotate.c
@@ -18,14 +18,6 @@
#include "internal.h"
#include "afs_fs.h"

-/*
- * Initialise a filesystem server cursor for iterating over FS servers.
- */
-static void afs_init_fs_cursor(struct afs_fs_cursor *fc, struct afs_vnode *vnode)
-{
- memset(fc, 0, sizeof(*fc));
-}
-
/*
* Begin an operation on the fileserver.
*
@@ -35,7 +27,7 @@ static void afs_init_fs_cursor(struct afs_fs_cursor *fc, struct afs_vnode *vnode
bool afs_begin_vnode_operation(struct afs_fs_cursor *fc, struct afs_vnode *vnode,
struct key *key)
{
- afs_init_fs_cursor(fc, vnode);
+ memset(fc, 0, sizeof(*fc));
fc->vnode = vnode;
fc->key = key;
fc->ac.error = SHRT_MAX;
@@ -66,12 +58,15 @@ static bool afs_start_fs_iteration(struct afs_fs_cursor *fc,
fc->server_list = afs_get_serverlist(vnode->volume->servers);
read_unlock(&vnode->volume->servers_lock);

+ fc->untried = (1UL << fc->server_list->nr_servers) - 1;
+ fc->index = READ_ONCE(fc->server_list->preferred);
+
cbi = vnode->cb_interest;
if (cbi) {
/* See if the vnode's preferred record is still available */
for (i = 0; i < fc->server_list->nr_servers; i++) {
if (fc->server_list->servers[i].cb_interest == cbi) {
- fc->start = i;
+ fc->index = i;
goto found_interest;
}
}
@@ -95,12 +90,9 @@ static bool afs_start_fs_iteration(struct afs_fs_cursor *fc,

afs_put_cb_interest(afs_v2net(vnode), cbi);
cbi = NULL;
- } else {
- fc->start = READ_ONCE(fc->server_list->index);
}

found_interest:
- fc->index = fc->start;
return true;
}

@@ -144,11 +136,12 @@ bool afs_select_fileserver(struct afs_fs_cursor *fc)
struct afs_addr_list *alist;
struct afs_server *server;
struct afs_vnode *vnode = fc->vnode;
- int error = fc->ac.error;
+ u32 rtt, abort_code;
+ int error = fc->ac.error, i;

- _enter("%u/%u,%u/%u,%d,%d",
- fc->index, fc->start,
- fc->ac.index, fc->ac.start,
+ _enter("%lx[%d],%lx[%d],%d,%d",
+ fc->untried, fc->index,
+ fc->ac.tried, fc->ac.index,
error, fc->ac.abort_code);

if (fc->flags & AFS_FS_CURSOR_STOP) {
@@ -345,8 +338,50 @@ bool afs_select_fileserver(struct afs_fs_cursor *fc)
if (!afs_start_fs_iteration(fc, vnode))
goto failed;

-use_server:
- _debug("use");
+ _debug("__ VOL %llx __", vnode->volume->vid);
+ error = afs_probe_fileservers(afs_v2net(vnode), fc->key, fc->server_list);
+ if (error < 0)
+ goto failed_set_error;
+
+pick_server:
+ _debug("pick [%lx]", fc->untried);
+
+ error = afs_wait_for_fs_probes(fc->server_list, fc->untried);
+ if (error < 0)
+ goto failed_set_error;
+
+ /* Pick the untried server with the lowest RTT. If we have outstanding
+ * callbacks, we stick with the server we're already using if we can.
+ */
+ if (fc->cbi) {
+ _debug("cbi %u", fc->index);
+ if (test_bit(fc->index, &fc->untried))
+ goto selected_server;
+ afs_put_cb_interest(afs_v2net(vnode), fc->cbi);
+ fc->cbi = NULL;
+ _debug("nocbi");
+ }
+
+ fc->index = -1;
+ rtt = U32_MAX;
+ for (i = 0; i < fc->server_list->nr_servers; i++) {
+ struct afs_server *s = fc->server_list->servers[i].server;
+
+ if (!test_bit(i, &fc->untried) || !s->probe.responded)
+ continue;
+ if (s->probe.rtt < rtt) {
+ fc->index = i;
+ rtt = s->probe.rtt;
+ }
+ }
+
+ if (fc->index == -1)
+ goto no_more_servers;
+
+selected_server:
+ _debug("use %d", fc->index);
+ __clear_bit(fc->index, &fc->untried);
+
/* We're starting on a different fileserver from the list. We need to
* check it, create a callback intercept, find its address list and
* probe its capabilities before we use it.
@@ -379,60 +414,81 @@ bool afs_select_fileserver(struct afs_fs_cursor *fc)

memset(&fc->ac, 0, sizeof(fc->ac));

- /* Probe the current fileserver if we haven't done so yet. */
- if (!test_bit(AFS_SERVER_FL_PROBED, &server->flags)) {
- fc->ac.alist = afs_get_addrlist(alist);
-
- if (!afs_probe_fileserver(fc)) {
- switch (fc->ac.error) {
- case -ENOMEM:
- case -ERESTARTSYS:
- case -EINTR:
- goto failed;
- default:
- goto next_server;
- }
- }
- }
-
if (!fc->ac.alist)
fc->ac.alist = alist;
else
afs_put_addrlist(alist);

- fc->ac.start = READ_ONCE(alist->index);
- fc->ac.index = fc->ac.start;
+ fc->ac.index = -1;

iterate_address:
ASSERT(fc->ac.alist);
- _debug("iterate %d/%d", fc->ac.index, fc->ac.alist->nr_addrs);
/* Iterate over the current server's address list to try and find an
* address on which it will respond to us.
*/
if (!afs_iterate_addresses(&fc->ac))
goto next_server;

+ _debug("address [%u] %u/%u", fc->index, fc->ac.index, fc->ac.alist->nr_addrs);
+
_leave(" = t");
return true;

next_server:
_debug("next");
afs_end_cursor(&fc->ac);
- afs_put_cb_interest(afs_v2net(vnode), fc->cbi);
- fc->cbi = NULL;
- fc->index++;
- if (fc->index >= fc->server_list->nr_servers)
- fc->index = 0;
- if (fc->index != fc->start)
- goto use_server;
+ goto pick_server;

+no_more_servers:
/* That's all the servers poked to no good effect. Try again if some
* of them were busy.
*/
if (fc->flags & AFS_FS_CURSOR_VBUSY)
goto restart_from_beginning;

- goto failed;
+ abort_code = 0;
+ error = -EDESTADDRREQ;
+ for (i = 0; i < fc->server_list->nr_servers; i++) {
+ struct afs_server *s = fc->server_list->servers[i].server;
+ int probe_error = READ_ONCE(s->probe.error);
+
+ switch (probe_error) {
+ case 0:
+ continue;
+ default:
+ if (error == -ETIMEDOUT ||
+ error == -ETIME)
+ continue;
+ case -ETIMEDOUT:
+ case -ETIME:
+ if (error == -ENOMEM ||
+ error == -ENONET)
+ continue;
+ case -ENOMEM:
+ case -ENONET:
+ if (error == -ENETUNREACH)
+ continue;
+ case -ENETUNREACH:
+ if (error == -EHOSTUNREACH)
+ continue;
+ case -EHOSTUNREACH:
+ if (error == -ECONNREFUSED)
+ continue;
+ case -ECONNREFUSED:
+ if (error == -ECONNRESET)
+ continue;
+ case -ECONNRESET: /* Responded, but call expired. */
+ if (error == -ECONNABORTED)
+ continue;
+ case -ECONNABORTED:
+ abort_code = s->probe.abort_code;
+ error = probe_error;
+ continue;
+ }
+ }
+
+ if (error == -ECONNABORTED)
+ error = afs_abort_to_error(abort_code);

failed_set_error:
fc->error = error;
@@ -480,8 +536,7 @@ bool afs_select_current_fileserver(struct afs_fs_cursor *fc)

memset(&fc->ac, 0, sizeof(fc->ac));
fc->ac.alist = alist;
- fc->ac.start = READ_ONCE(alist->index);
- fc->ac.index = fc->ac.start;
+ fc->ac.index = -1;
goto iterate_address;

case 0:
@@ -538,13 +593,13 @@ static void afs_dump_edestaddrreq(const struct afs_fs_cursor *fc)
pr_notice("EDESTADDR occurred\n");
pr_notice("FC: cbb=%x cbb2=%x fl=%hx err=%hd\n",
fc->cb_break, fc->cb_break_2, fc->flags, fc->error);
- pr_notice("FC: st=%u ix=%u ni=%u\n",
- fc->start, fc->index, fc->nr_iterations);
+ pr_notice("FC: ut=%lx ix=%d ni=%u\n",
+ fc->untried, fc->index, fc->nr_iterations);

if (fc->server_list) {
const struct afs_server_list *sl = fc->server_list;
- pr_notice("FC: SL nr=%u ix=%u vnov=%hx\n",
- sl->nr_servers, sl->index, sl->vnovol_mask);
+ pr_notice("FC: SL nr=%u pr=%u vnov=%hx\n",
+ sl->nr_servers, sl->preferred, sl->vnovol_mask);
for (i = 0; i < sl->nr_servers; i++) {
const struct afs_server *s = sl->servers[i].server;
pr_notice("FC: server fl=%lx av=%u %pU\n",
@@ -552,22 +607,21 @@ static void afs_dump_edestaddrreq(const struct afs_fs_cursor *fc)
if (s->addresses) {
const struct afs_addr_list *a =
rcu_dereference(s->addresses);
- pr_notice("FC: - av=%u nr=%u/%u/%u ax=%u\n",
+ pr_notice("FC: - av=%u nr=%u/%u/%u pr=%u\n",
a->version,
a->nr_ipv4, a->nr_addrs, a->max_addrs,
- a->index);
- pr_notice("FC: - pr=%lx yf=%lx\n",
- a->probed, a->yfs);
+ a->preferred);
+ pr_notice("FC: - pr=%lx R=%lx F=%lx\n",
+ a->probed, a->responded, a->failed);
if (a == fc->ac.alist)
pr_notice("FC: - current\n");
}
}
}

- pr_notice("AC: as=%u ax=%u ac=%d er=%d b=%u r=%u ni=%u\n",
- fc->ac.start, fc->ac.index, fc->ac.abort_code, fc->ac.error,
- fc->ac.begun, fc->ac.responded, fc->ac.nr_iterations);
-
+ pr_notice("AC: t=%lx ax=%u ac=%d er=%d r=%u ni=%u\n",
+ fc->ac.tried, fc->ac.index, fc->ac.abort_code, fc->ac.error,
+ fc->ac.responded, fc->ac.nr_iterations);
rcu_read_unlock();
}

diff --git a/fs/afs/rxrpc.c b/fs/afs/rxrpc.c
index 42e1ea7372e9..59970886690f 100644
--- a/fs/afs/rxrpc.c
+++ b/fs/afs/rxrpc.c
@@ -43,7 +43,6 @@ int afs_open_socket(struct afs_net *net)
struct sockaddr_rxrpc srx;
struct socket *socket;
unsigned int min_level;
- u16 service_upgrade[2];
int ret;

_enter("");
@@ -82,13 +81,12 @@ int afs_open_socket(struct afs_net *net)
if (ret < 0)
goto error_2;

- service_upgrade[0] = CM_SERVICE;
- service_upgrade[1] = YFS_CM_SERVICE;
- ret = kernel_setsockopt(socket, SOL_RXRPC, RXRPC_UPGRADEABLE_SERVICE,
- (void *)service_upgrade, sizeof(service_upgrade));
- if (ret < 0)
- goto error_2;
-
+ /* Ideally, we'd turn on service upgrade here, but we can't because
+ * OpenAFS is buggy and leaks the userStatus field from packet to
+ * packet and between FS packets and CB packets - so if we try to do an
+ * upgrade on an FS packet, OpenAFS will leak that into the CB packet
+ * it sends back to us.
+ */

rxrpc_kernel_new_call_notification(socket, afs_rx_new_call,
afs_rx_discard_new_call);
@@ -192,6 +190,7 @@ void afs_put_call(struct afs_call *call)

afs_put_server(call->net, call->cm_server);
afs_put_cb_interest(call->net, call->cbi);
+ afs_put_addrlist(call->alist);
kfree(call->request);

trace_afs_call(call, afs_call_trace_free, 0, o,
@@ -205,21 +204,22 @@ void afs_put_call(struct afs_call *call)
}

/*
- * Queue the call for actual work. Returns 0 unconditionally for convenience.
+ * Queue the call for actual work.
*/
-int afs_queue_call_work(struct afs_call *call)
+static void afs_queue_call_work(struct afs_call *call)
{
- int u = atomic_inc_return(&call->usage);
+ if (call->type->work) {
+ int u = atomic_inc_return(&call->usage);

- trace_afs_call(call, afs_call_trace_work, u,
- atomic_read(&call->net->nr_outstanding_calls),
- __builtin_return_address(0));
+ trace_afs_call(call, afs_call_trace_work, u,
+ atomic_read(&call->net->nr_outstanding_calls),
+ __builtin_return_address(0));

- INIT_WORK(&call->work, call->type->work);
+ INIT_WORK(&call->work, call->type->work);

- if (!queue_work(afs_wq, &call->work))
- afs_put_call(call);
- return 0;
+ if (!queue_work(afs_wq, &call->work))
+ afs_put_call(call);
+ }
}

/*
@@ -376,6 +376,8 @@ long afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call,
atomic_read(&call->net->nr_outstanding_calls));

call->async = async;
+ call->addr_ix = ac->index;
+ call->alist = afs_get_addrlist(ac->alist);

/* Work out the length we're going to transmit. This is awkward for
* calls such as FS.StoreData where there's an extra injection of data
@@ -407,6 +409,7 @@ long afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call,
call->debug_id);
if (IS_ERR(rxcall)) {
ret = PTR_ERR(rxcall);
+ call->error = ret;
goto error_kill_call;
}

@@ -458,6 +461,8 @@ long afs_make_call(struct afs_addr_cursor *ac, struct afs_call *call,
call->error = ret;
trace_afs_call_done(call);
error_kill_call:
+ if (call->type->done)
+ call->type->done(call);
afs_put_call(call);
ac->error = ret;
_leave(" = %d", ret);
@@ -509,6 +514,7 @@ static void afs_deliver_to_call(struct afs_call *call)
state = READ_ONCE(call->state);
switch (ret) {
case 0:
+ afs_queue_call_work(call);
if (state == AFS_CALL_CL_PROC_REPLY) {
if (call->cbi)
set_bit(AFS_SERVER_FL_MAY_HAVE_CB,
@@ -546,6 +552,8 @@ static void afs_deliver_to_call(struct afs_call *call)
}

done:
+ if (call->type->done)
+ call->type->done(call);
if (state == AFS_CALL_COMPLETE && call->incoming)
afs_put_call(call);
out:
diff --git a/fs/afs/server.c b/fs/afs/server.c
index 7c1be8b4dc9a..642afa2e9783 100644
--- a/fs/afs/server.c
+++ b/fs/afs/server.c
@@ -231,6 +231,8 @@ static struct afs_server *afs_alloc_server(struct afs_net *net,
rwlock_init(&server->fs_lock);
INIT_HLIST_HEAD(&server->cb_volumes);
rwlock_init(&server->cb_break_lock);
+ init_waitqueue_head(&server->probe_wq);
+ spin_lock_init(&server->probe_lock);

afs_inc_servers_outstanding(net);
_leave(" = %p", server);
@@ -254,7 +256,7 @@ static struct afs_addr_list *afs_vl_lookup_addrs(struct afs_cell *cell,
ret = -ERESTARTSYS;
if (afs_begin_vlserver_operation(&vc, cell, key)) {
while (afs_select_vlserver(&vc)) {
- if (test_bit(vc.ac.index, &vc.ac.alist->yfs))
+ if (test_bit(AFS_VLSERVER_FL_IS_YFS, &vc.server->flags))
alist = afs_yfsvl_get_endpoints(&vc, uuid);
else
alist = afs_vl_get_addrs_u(&vc, uuid);
@@ -365,8 +367,7 @@ static void afs_destroy_server(struct afs_net *net, struct afs_server *server)
struct afs_addr_list *alist = rcu_access_pointer(server->addresses);
struct afs_addr_cursor ac = {
.alist = alist,
- .start = alist->index,
- .index = 0,
+ .index = alist->preferred,
.error = 0,
};
_enter("%p", server);
@@ -374,6 +375,9 @@ static void afs_destroy_server(struct afs_net *net, struct afs_server *server)
if (test_bit(AFS_SERVER_FL_MAY_HAVE_CB, &server->flags))
afs_fs_give_up_all_callbacks(net, server, &ac, NULL);

+ wait_var_event(&server->probe_outstanding,
+ atomic_read(&server->probe_outstanding) == 0);
+
call_rcu(&server->rcu, afs_server_rcu);
afs_dec_servers_outstanding(net);
}
@@ -506,105 +510,6 @@ void afs_purge_servers(struct afs_net *net)
_leave("");
}

-/*
- * Probe a fileserver to find its capabilities.
- *
- * TODO: Try service upgrade.
- */
-static bool afs_do_probe_fileserver(struct afs_fs_cursor *fc)
-{
- int i;
-
- _enter("");
-
- fc->ac.start = READ_ONCE(fc->ac.alist->index);
- fc->ac.index = fc->ac.start;
- fc->ac.error = 0;
- fc->ac.begun = false;
-
- while (afs_iterate_addresses(&fc->ac)) {
- afs_fs_get_capabilities(afs_v2net(fc->vnode), fc->cbi->server,
- &fc->ac, fc->key);
- switch (fc->ac.error) {
- case 0:
- if (test_bit(AFS_SERVER_FL_IS_YFS, &fc->cbi->server->flags)) {
- for (i = 0; i < fc->ac.alist->nr_addrs; i++)
- fc->ac.alist->addrs[i].srx_service =
- YFS_FS_SERVICE;
- }
- afs_end_cursor(&fc->ac);
- set_bit(AFS_SERVER_FL_PROBED, &fc->cbi->server->flags);
- return true;
- case -ECONNABORTED:
- fc->ac.error = afs_abort_to_error(fc->ac.abort_code);
- goto error;
- case -ENOMEM:
- case -ENONET:
- goto error;
- case -ENETUNREACH:
- case -EHOSTUNREACH:
- case -ECONNREFUSED:
- case -ETIMEDOUT:
- case -ETIME:
- break;
- default:
- fc->ac.error = afs_io_error(NULL, afs_io_error_fs_probe_fail);
- goto error;
- }
- }
-
-error:
- afs_end_cursor(&fc->ac);
- return false;
-}
-
-/*
- * If we haven't already, try probing the fileserver to get its capabilities.
- * We try not to instigate parallel probes, but it's possible that the parallel
- * probes will fail due to authentication failure when ours would succeed.
- *
- * TODO: Try sending an anonymous probe if an authenticated probe fails.
- */
-bool afs_probe_fileserver(struct afs_fs_cursor *fc)
-{
- bool success;
- int ret, retries = 0;
-
- _enter("");
-
-retry:
- if (test_bit(AFS_SERVER_FL_PROBED, &fc->cbi->server->flags)) {
- _leave(" = t");
- return true;
- }
-
- if (!test_and_set_bit_lock(AFS_SERVER_FL_PROBING, &fc->cbi->server->flags)) {
- success = afs_do_probe_fileserver(fc);
- clear_bit_unlock(AFS_SERVER_FL_PROBING, &fc->cbi->server->flags);
- wake_up_bit(&fc->cbi->server->flags, AFS_SERVER_FL_PROBING);
- _leave(" = t");
- return success;
- }
-
- _debug("wait");
- ret = wait_on_bit(&fc->cbi->server->flags, AFS_SERVER_FL_PROBING,
- TASK_INTERRUPTIBLE);
- if (ret == -ERESTARTSYS) {
- fc->ac.error = ret;
- _leave(" = f [%d]", ret);
- return false;
- }
-
- retries++;
- if (retries == 4) {
- fc->ac.error = -ESTALE;
- _leave(" = f [stale]");
- return false;
- }
- _debug("retry");
- goto retry;
-}
-
/*
* Get an update for a server's address list.
*/
diff --git a/fs/afs/server_list.c b/fs/afs/server_list.c
index 8a5760aa5832..95d0761cdb34 100644
--- a/fs/afs/server_list.c
+++ b/fs/afs/server_list.c
@@ -118,11 +118,11 @@ bool afs_annotate_server_list(struct afs_server_list *new,
return false;

changed:
- /* Maintain the same current server as before if possible. */
- cur = old->servers[old->index].server;
+ /* Maintain the same preferred server as before if possible. */
+ cur = old->servers[old->preferred].server;
for (j = 0; j < new->nr_servers; j++) {
if (new->servers[j].server == cur) {
- new->index = j;
+ new->preferred = j;
break;
}
}
diff --git a/fs/afs/vl_list.c b/fs/afs/vl_list.c
index c1e316ba105a..b4f1a84519b9 100644
--- a/fs/afs/vl_list.c
+++ b/fs/afs/vl_list.c
@@ -23,6 +23,8 @@ struct afs_vlserver *afs_alloc_vlserver(const char *name, size_t name_len,
if (vlserver) {
atomic_set(&vlserver->usage, 1);
rwlock_init(&vlserver->lock);
+ init_waitqueue_head(&vlserver->probe_wq);
+ spin_lock_init(&vlserver->probe_lock);
vlserver->name_len = name_len;
vlserver->port = port;
memcpy(vlserver->name, name, name_len);
@@ -141,7 +143,7 @@ static struct afs_addr_list *afs_extract_vl_addrs(const u8 **_b, const u8 *end,

/* Start with IPv6 if available. */
if (alist->nr_ipv4 < alist->nr_addrs)
- alist->index = alist->nr_ipv4;
+ alist->preferred = alist->nr_ipv4;

*_b = b;
return alist;
@@ -307,6 +309,8 @@ struct afs_vlserver_list *afs_extract_vlserver_list(struct afs_cell *cell,
(vllist->nr_servers - j) * sizeof(struct afs_vlserver_entry));
}

+ clear_bit(AFS_VLSERVER_FL_PROBED, &server->flags);
+
vllist->servers[j].priority = bs.priority;
vllist->servers[j].weight = bs.weight;
vllist->servers[j].server = server;
diff --git a/fs/afs/vl_probe.c b/fs/afs/vl_probe.c
new file mode 100644
index 000000000000..c0f616bd70cb
--- /dev/null
+++ b/fs/afs/vl_probe.c
@@ -0,0 +1,273 @@
+/* AFS vlserver probing
+ *
+ * Copyright (C) 2018 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@xxxxxxxxxx)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include "afs_fs.h"
+#include "internal.h"
+#include "protocol_yfs.h"
+
+static bool afs_vl_probe_done(struct afs_vlserver *server)
+{
+ if (!atomic_dec_and_test(&server->probe_outstanding))
+ return false;
+
+ wake_up_var(&server->probe_outstanding);
+ clear_bit_unlock(AFS_VLSERVER_FL_PROBING, &server->flags);
+ wake_up_bit(&server->flags, AFS_VLSERVER_FL_PROBING);
+ return true;
+}
+
+/*
+ * Process the result of probing a vlserver. This is called after successful
+ * or failed delivery of an VL.GetCapabilities operation.
+ */
+void afs_vlserver_probe_result(struct afs_call *call)
+{
+ struct afs_addr_list *alist = call->alist;
+ struct afs_vlserver *server = call->reply[0];
+ unsigned int server_index = (long)call->reply[1];
+ unsigned int index = call->addr_ix;
+ unsigned int rtt = UINT_MAX;
+ bool have_result = false;
+ u64 _rtt;
+ int ret = call->error;
+
+ _enter("%s,%u,%u,%d,%d", server->name, server_index, index, ret, call->abort_code);
+
+ spin_lock(&server->probe_lock);
+
+ switch (ret) {
+ case 0:
+ server->probe.error = 0;
+ goto responded;
+ case -ECONNABORTED:
+ if (!server->probe.responded) {
+ server->probe.abort_code = call->abort_code;
+ server->probe.error = ret;
+ }
+ goto responded;
+ case -ENOMEM:
+ case -ENONET:
+ server->probe.local_failure = true;
+ afs_io_error(call, afs_io_error_vl_probe_fail);
+ goto out;
+ case -ECONNRESET: /* Responded, but call expired. */
+ case -ENETUNREACH:
+ case -EHOSTUNREACH:
+ case -ECONNREFUSED:
+ case -ETIMEDOUT:
+ case -ETIME:
+ default:
+ clear_bit(index, &alist->responded);
+ set_bit(index, &alist->failed);
+ if (!server->probe.responded &&
+ (server->probe.error == 0 ||
+ server->probe.error == -ETIMEDOUT ||
+ server->probe.error == -ETIME))
+ server->probe.error = ret;
+ afs_io_error(call, afs_io_error_vl_probe_fail);
+ goto out;
+ }
+
+responded:
+ set_bit(index, &alist->responded);
+ clear_bit(index, &alist->failed);
+
+ if (call->service_id == YFS_VL_SERVICE) {
+ server->probe.is_yfs = true;
+ set_bit(AFS_VLSERVER_FL_IS_YFS, &server->flags);
+ alist->addrs[index].srx_service = call->service_id;
+ } else {
+ server->probe.not_yfs = true;
+ if (!server->probe.is_yfs) {
+ clear_bit(AFS_VLSERVER_FL_IS_YFS, &server->flags);
+ alist->addrs[index].srx_service = call->service_id;
+ }
+ }
+
+ /* Get the RTT and scale it to fit into a 32-bit value that represents
+ * over a minute of time so that we can access it with one instruction
+ * on a 32-bit system.
+ */
+ _rtt = rxrpc_kernel_get_rtt(call->net->socket, call->rxcall);
+ _rtt /= 64;
+ rtt = (_rtt > UINT_MAX) ? UINT_MAX : _rtt;
+ if (rtt < server->probe.rtt) {
+ server->probe.rtt = rtt;
+ alist->preferred = index;
+ have_result = true;
+ }
+
+ smp_wmb(); /* Set rtt before responded. */
+ server->probe.responded = true;
+ set_bit(AFS_VLSERVER_FL_PROBED, &server->flags);
+out:
+ spin_unlock(&server->probe_lock);
+
+ _debug("probe [%u][%u] %pISpc rtt=%u ret=%d",
+ server_index, index, &alist->addrs[index].transport,
+ (unsigned int)rtt, ret);
+
+ have_result |= afs_vl_probe_done(server);
+ if (have_result) {
+ server->probe.have_result = true;
+ wake_up_var(&server->probe.have_result);
+ wake_up_all(&server->probe_wq);
+ }
+}
+
+/*
+ * Probe all of a vlserver's addresses to find out the best route and to
+ * query its capabilities.
+ */
+static int afs_do_probe_vlserver(struct afs_net *net,
+ struct afs_vlserver *server,
+ struct key *key,
+ unsigned int server_index)
+{
+ struct afs_addr_cursor ac = {
+ .index = 0,
+ };
+ int ret;
+
+ _enter("%s", server->name);
+
+ read_lock(&server->lock);
+ ac.alist = rcu_dereference_protected(server->addresses,
+ lockdep_is_held(&server->lock));
+ read_unlock(&server->lock);
+
+ atomic_set(&server->probe_outstanding, ac.alist->nr_addrs);
+ memset(&server->probe, 0, sizeof(server->probe));
+ server->probe.rtt = UINT_MAX;
+
+ for (ac.index = 0; ac.index < ac.alist->nr_addrs; ac.index++) {
+ ret = afs_vl_get_capabilities(net, &ac, key, server,
+ server_index, true);
+ if (ret != -EINPROGRESS) {
+ afs_vl_probe_done(server);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Send off probes to all unprobed servers.
+ */
+int afs_send_vl_probes(struct afs_net *net, struct key *key,
+ struct afs_vlserver_list *vllist)
+{
+ struct afs_vlserver *server;
+ int i, ret;
+
+ for (i = 0; i < vllist->nr_servers; i++) {
+ server = vllist->servers[i].server;
+ if (test_bit(AFS_VLSERVER_FL_PROBED, &server->flags))
+ continue;
+
+ if (!test_and_set_bit_lock(AFS_VLSERVER_FL_PROBING, &server->flags)) {
+ ret = afs_do_probe_vlserver(net, server, key, i);
+ if (ret)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Wait for the first as-yet untried server to respond.
+ */
+int afs_wait_for_vl_probes(struct afs_vlserver_list *vllist,
+ unsigned long untried)
+{
+ struct wait_queue_entry *waits;
+ struct afs_vlserver *server;
+ unsigned int rtt = UINT_MAX;
+ bool have_responders = false;
+ int pref = -1, i;
+
+ _enter("%u,%lx", vllist->nr_servers, untried);
+
+ /* Only wait for servers that have a probe outstanding. */
+ for (i = 0; i < vllist->nr_servers; i++) {
+ if (test_bit(i, &untried)) {
+ server = vllist->servers[i].server;
+ if (!test_bit(AFS_VLSERVER_FL_PROBING, &server->flags))
+ __clear_bit(i, &untried);
+ if (server->probe.responded)
+ have_responders = true;
+ }
+ }
+ if (have_responders || !untried)
+ return 0;
+
+ waits = kmalloc(array_size(vllist->nr_servers, sizeof(*waits)), GFP_KERNEL);
+ if (!waits)
+ return -ENOMEM;
+
+ for (i = 0; i < vllist->nr_servers; i++) {
+ if (test_bit(i, &untried)) {
+ server = vllist->servers[i].server;
+ init_waitqueue_entry(&waits[i], current);
+ add_wait_queue(&server->probe_wq, &waits[i]);
+ }
+ }
+
+ for (;;) {
+ bool still_probing = false;
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ for (i = 0; i < vllist->nr_servers; i++) {
+ if (test_bit(i, &untried)) {
+ server = vllist->servers[i].server;
+ if (server->probe.responded)
+ goto stop;
+ if (test_bit(AFS_VLSERVER_FL_PROBING, &server->flags))
+ still_probing = true;
+ }
+ }
+
+ if (!still_probing || unlikely(signal_pending(current)))
+ goto stop;
+ schedule();
+ }
+
+stop:
+ set_current_state(TASK_RUNNING);
+
+ for (i = 0; i < vllist->nr_servers; i++) {
+ if (test_bit(i, &untried)) {
+ server = vllist->servers[i].server;
+ if (server->probe.responded &&
+ server->probe.rtt < rtt) {
+ pref = i;
+ rtt = server->probe.rtt;
+ }
+
+ remove_wait_queue(&server->probe_wq, &waits[i]);
+ }
+ }
+
+ kfree(waits);
+
+ if (pref == -1 && signal_pending(current))
+ return -ERESTARTSYS;
+
+ if (pref >= 0)
+ vllist->preferred = pref;
+
+ _leave(" = 0 [%u]", pref);
+ return 0;
+}
diff --git a/fs/afs/vl_rotate.c b/fs/afs/vl_rotate.c
index ead6dedbb561..b64a284b99d2 100644
--- a/fs/afs/vl_rotate.c
+++ b/fs/afs/vl_rotate.c
@@ -58,8 +58,8 @@ static bool afs_start_vl_iteration(struct afs_vl_cursor *vc)
if (!vc->server_list || !vc->server_list->nr_servers)
return false;

- vc->start = READ_ONCE(vc->server_list->index);
- vc->index = vc->start;
+ vc->untried = (1UL << vc->server_list->nr_servers) - 1;
+ vc->index = -1;
return true;
}

@@ -71,11 +71,12 @@ bool afs_select_vlserver(struct afs_vl_cursor *vc)
{
struct afs_addr_list *alist;
struct afs_vlserver *vlserver;
- int error = vc->ac.error;
+ u32 rtt;
+ int error = vc->ac.error, abort_code, i;

- _enter("%u/%u,%u/%u,%d,%d",
- vc->index, vc->start,
- vc->ac.index, vc->ac.start,
+ _enter("%lx[%d],%lx[%d],%d,%d",
+ vc->untried, vc->index,
+ vc->ac.tried, vc->ac.index,
error, vc->ac.abort_code);

if (vc->flags & AFS_VL_CURSOR_STOP) {
@@ -145,23 +146,52 @@ bool afs_select_vlserver(struct afs_vl_cursor *vc)
start:
_debug("start");

- /* TODO: Consider checking the VL server list */
-
if (!afs_start_vl_iteration(vc))
goto failed;

-use_server:
- _debug("use");
+ error = afs_send_vl_probes(vc->cell->net, vc->key, vc->server_list);
+ if (error < 0)
+ goto failed_set_error;
+
+pick_server:
+ _debug("pick [%lx]", vc->untried);
+
+ error = afs_wait_for_vl_probes(vc->server_list, vc->untried);
+ if (error < 0)
+ goto failed_set_error;
+
+ /* Pick the untried server with the lowest RTT. */
+ vc->index = vc->server_list->preferred;
+ if (test_bit(vc->index, &vc->untried))
+ goto selected_server;
+
+ vc->index = -1;
+ rtt = U32_MAX;
+ for (i = 0; i < vc->server_list->nr_servers; i++) {
+ struct afs_vlserver *s = vc->server_list->servers[i].server;
+
+ if (!test_bit(i, &vc->untried) || !s->probe.responded)
+ continue;
+ if (s->probe.rtt < rtt) {
+ vc->index = i;
+ rtt = s->probe.rtt;
+ }
+ }
+
+ if (vc->index == -1)
+ goto no_more_servers;
+
+selected_server:
+ _debug("use %d", vc->index);
+ __clear_bit(vc->index, &vc->untried);
+
/* We're starting on a different vlserver from the list. We need to
* check it, find its address list and probe its capabilities before we
* use it.
*/
ASSERTCMP(vc->ac.alist, ==, NULL);
vlserver = vc->server_list->servers[vc->index].server;
-
- // TODO: Check the vlserver occasionally
- //if (!afs_check_vlserver_record(vc, vlserver))
- // goto failed;
+ vc->server = vlserver;

_debug("USING VLSERVER: %s", vlserver->name);

@@ -173,62 +203,84 @@ bool afs_select_vlserver(struct afs_vl_cursor *vc)

memset(&vc->ac, 0, sizeof(vc->ac));

- /* Probe the current vlserver if we haven't done so yet. */
-#if 0 // TODO
- if (!test_bit(AFS_VLSERVER_FL_PROBED, &vlserver->flags)) {
- vc->ac.alist = afs_get_addrlist(alist);
-
- if (!afs_probe_vlserver(vc)) {
- error = vc->ac.error;
- switch (error) {
- case -ENOMEM:
- case -ERESTARTSYS:
- case -EINTR:
- goto failed_set_error;
- default:
- goto next_server;
- }
- }
- }
-#endif
-
if (!vc->ac.alist)
vc->ac.alist = alist;
else
afs_put_addrlist(alist);

- vc->ac.start = READ_ONCE(alist->index);
- vc->ac.index = vc->ac.start;
+ vc->ac.index = -1;

iterate_address:
ASSERT(vc->ac.alist);
- _debug("iterate %d/%d", vc->ac.index, vc->ac.alist->nr_addrs);
/* Iterate over the current server's address list to try and find an
* address on which it will respond to us.
*/
if (!afs_iterate_addresses(&vc->ac))
goto next_server;

+ _debug("VL address %d/%d", vc->ac.index, vc->ac.alist->nr_addrs);
+
_leave(" = t %pISpc", &vc->ac.alist->addrs[vc->ac.index].transport);
return true;

next_server:
_debug("next");
afs_end_cursor(&vc->ac);
- vc->index++;
- if (vc->index >= vc->server_list->nr_servers)
- vc->index = 0;
- if (vc->index != vc->start)
- goto use_server;
+ goto pick_server;

+no_more_servers:
/* That's all the servers poked to no good effect. Try again if some
* of them were busy.
*/
if (vc->flags & AFS_VL_CURSOR_RETRY)
goto restart_from_beginning;

- goto failed;
+ abort_code = 0;
+ error = -EDESTADDRREQ;
+ for (i = 0; i < vc->server_list->nr_servers; i++) {
+ struct afs_vlserver *s = vc->server_list->servers[i].server;
+ int probe_error = READ_ONCE(s->probe.error);
+
+ switch (probe_error) {
+ case 0:
+ continue;
+ default:
+ if (error == -ETIMEDOUT ||
+ error == -ETIME)
+ continue;
+ case -ETIMEDOUT:
+ case -ETIME:
+ if (error == -ENOMEM ||
+ error == -ENONET)
+ continue;
+ case -ENOMEM:
+ case -ENONET:
+ if (error == -ENETUNREACH)
+ continue;
+ case -ENETUNREACH:
+ if (error == -EHOSTUNREACH)
+ continue;
+ case -EHOSTUNREACH:
+ if (error == -ECONNREFUSED)
+ continue;
+ case -ECONNREFUSED:
+ if (error == -ECONNRESET)
+ continue;
+ case -ECONNRESET: /* Responded, but call expired. */
+ if (error == -ECONNABORTED)
+ continue;
+ case -ECONNABORTED:
+ abort_code = s->probe.abort_code;
+ error = probe_error;
+ continue;
+ }
+ }
+
+ if (error == -ECONNABORTED)
+ error = afs_abort_to_error(abort_code);

+failed_set_error:
+ vc->error = error;
failed:
vc->flags |= AFS_VL_CURSOR_STOP;
afs_end_cursor(&vc->ac);
@@ -250,8 +302,8 @@ static void afs_vl_dump_edestaddrreq(const struct afs_vl_cursor *vc)

rcu_read_lock();
pr_notice("EDESTADDR occurred\n");
- pr_notice("VC: st=%u ix=%u ni=%hu fl=%hx err=%hd\n",
- vc->start, vc->index, vc->nr_iterations, vc->flags, vc->error);
+ pr_notice("VC: ut=%lx ix=%u ni=%hu fl=%hx err=%hd\n",
+ vc->untried, vc->index, vc->nr_iterations, vc->flags, vc->error);

if (vc->server_list) {
const struct afs_vlserver_list *sl = vc->server_list;
@@ -259,26 +311,25 @@ static void afs_vl_dump_edestaddrreq(const struct afs_vl_cursor *vc)
sl->nr_servers, sl->index);
for (i = 0; i < sl->nr_servers; i++) {
const struct afs_vlserver *s = sl->servers[i].server;
- pr_notice("VC: server fl=%lx %s+%hu\n",
- s->flags, s->name, s->port);
+ pr_notice("VC: server %s+%hu fl=%lx E=%hd\n",
+ s->name, s->port, s->flags, s->probe.error);
if (s->addresses) {
const struct afs_addr_list *a =
rcu_dereference(s->addresses);
- pr_notice("VC: - av=%u nr=%u/%u/%u ax=%u\n",
- a->version,
+ pr_notice("VC: - nr=%u/%u/%u pf=%u\n",
a->nr_ipv4, a->nr_addrs, a->max_addrs,
- a->index);
- pr_notice("VC: - pr=%lx yf=%lx\n",
- a->probed, a->yfs);
+ a->preferred);
+ pr_notice("VC: - pr=%lx R=%lx F=%lx\n",
+ a->probed, a->responded, a->failed);
if (a == vc->ac.alist)
pr_notice("VC: - current\n");
}
}
}

- pr_notice("AC: as=%u ax=%u ac=%d er=%d b=%u r=%u ni=%hu\n",
- vc->ac.start, vc->ac.index, vc->ac.abort_code, vc->ac.error,
- vc->ac.begun, vc->ac.responded, vc->ac.nr_iterations);
+ pr_notice("AC: t=%lx ax=%u ac=%d er=%d r=%u ni=%u\n",
+ vc->ac.tried, vc->ac.index, vc->ac.abort_code, vc->ac.error,
+ vc->ac.responded, vc->ac.nr_iterations);
rcu_read_unlock();
}

diff --git a/fs/afs/vlclient.c b/fs/afs/vlclient.c
index 3127ab9b5521..c3d9e5a5f67e 100644
--- a/fs/afs/vlclient.c
+++ b/fs/afs/vlclient.c
@@ -348,12 +348,18 @@ static int afs_deliver_vl_get_capabilities(struct afs_call *call)
break;
}

- call->reply[0] = (void *)(unsigned long)call->service_id;
-
_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
*/
@@ -361,7 +367,8 @@ static const struct afs_call_type afs_RXVLGetCapabilities = {
.name = "VL.GetCapabilities",
.op = afs_VL_GetCapabilities,
.deliver = afs_deliver_vl_get_capabilities,
- .destructor = afs_flat_call_destructor,
+ .done = afs_vlserver_probe_result,
+ .destructor = afs_destroy_vl_get_capabilities,
};

/*
@@ -371,8 +378,12 @@ static const struct afs_call_type afs_RXVLGetCapabilities = {
* 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)
+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;
@@ -384,9 +395,10 @@ int afs_vl_get_capabilities(struct afs_net *net, struct afs_addr_cursor *ac,
return -ENOMEM;

call->key = key;
- call->upgrade = true; /* Let's see if this is a YFS server */
- call->reply[0] = (void *)VLGETCAPABILITIES;
- call->ret_reply0 = true;
+ 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;
@@ -394,7 +406,7 @@ int afs_vl_get_capabilities(struct afs_net *net, struct afs_addr_cursor *ac,

/* Can't take a ref on server */
trace_afs_make_vl_call(call);
- return afs_make_call(ac, call, GFP_KERNEL, false);
+ return afs_make_call(ac, call, GFP_KERNEL, async);
}

/*
@@ -591,11 +603,6 @@ static int afs_deliver_yfsvl_get_endpoints(struct afs_call *call)
}

alist = call->reply[0];
-
- /* Start with IPv6 if available. */
- if (alist->nr_ipv4 < alist->nr_addrs)
- alist->index = alist->nr_ipv4;
-
_leave(" = 0 [done]");
return 0;
}
diff --git a/fs/afs/volume.c b/fs/afs/volume.c
index 7527c081726e..00975ed3640f 100644
--- a/fs/afs/volume.c
+++ b/fs/afs/volume.c
@@ -82,22 +82,6 @@ static struct afs_vldb_entry *afs_vl_lookup_vldb(struct afs_cell *cell,
return ERR_PTR(-ERESTARTSYS);

while (afs_select_vlserver(&vc)) {
- if (!test_bit(vc.ac.index, &vc.ac.alist->probed)) {
- ret = afs_vl_get_capabilities(cell->net, &vc.ac, key);
- switch (ret) {
- case VL_SERVICE:
- clear_bit(vc.ac.index, &vc.ac.alist->yfs);
- set_bit(vc.ac.index, &vc.ac.alist->probed);
- vc.ac.alist->addrs[vc.ac.index].srx_service = ret;
- break;
- case YFS_VL_SERVICE:
- set_bit(vc.ac.index, &vc.ac.alist->yfs);
- set_bit(vc.ac.index, &vc.ac.alist->probed);
- vc.ac.alist->addrs[vc.ac.index].srx_service = ret;
- break;
- }
- }
-
vldb = afs_vl_get_entry_by_name_u(&vc, volname, volnamesz);
}

diff --git a/include/trace/events/afs.h b/include/trace/events/afs.h
index ed155042236b..33d291888ba9 100644
--- a/include/trace/events/afs.h
+++ b/include/trace/events/afs.h
@@ -137,6 +137,7 @@ enum afs_io_error {
afs_io_error_extract,
afs_io_error_fs_probe_fail,
afs_io_error_vl_lookup_fail,
+ afs_io_error_vl_probe_fail,
};

enum afs_file_error {
@@ -261,7 +262,8 @@ enum afs_file_error {
EM(afs_io_error_cm_reply, "CM_REPLY") \
EM(afs_io_error_extract, "EXTRACT") \
EM(afs_io_error_fs_probe_fail, "FS_PROBE_FAIL") \
- E_(afs_io_error_vl_lookup_fail, "VL_LOOKUP_FAIL")
+ EM(afs_io_error_vl_lookup_fail, "VL_LOOKUP_FAIL") \
+ E_(afs_io_error_vl_probe_fail, "VL_PROBE_FAIL")

#define afs_file_errors \
EM(afs_file_error_dir_bad_magic, "DIR_BAD_MAGIC") \