summaryrefslogtreecommitdiffstats
path: root/fs/afs/cmservice.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/afs/cmservice.c')
-rw-r--r--fs/afs/cmservice.c652
1 files changed, 652 insertions, 0 deletions
diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c
new file mode 100644
index 0000000..0a57fd7
--- /dev/null
+++ b/fs/afs/cmservice.c
@@ -0,0 +1,652 @@
+/* cmservice.c: AFS Cache Manager Service
+ *
+ * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/completion.h>
+#include "server.h"
+#include "cell.h"
+#include "transport.h"
+#include <rxrpc/rxrpc.h>
+#include <rxrpc/transport.h>
+#include <rxrpc/connection.h>
+#include <rxrpc/call.h>
+#include "cmservice.h"
+#include "internal.h"
+
+static unsigned afscm_usage; /* AFS cache manager usage count */
+static struct rw_semaphore afscm_sem; /* AFS cache manager start/stop semaphore */
+
+static int afscm_new_call(struct rxrpc_call *call);
+static void afscm_attention(struct rxrpc_call *call);
+static void afscm_error(struct rxrpc_call *call);
+static void afscm_aemap(struct rxrpc_call *call);
+
+static void _SRXAFSCM_CallBack(struct rxrpc_call *call);
+static void _SRXAFSCM_InitCallBackState(struct rxrpc_call *call);
+static void _SRXAFSCM_Probe(struct rxrpc_call *call);
+
+typedef void (*_SRXAFSCM_xxxx_t)(struct rxrpc_call *call);
+
+static const struct rxrpc_operation AFSCM_ops[] = {
+ {
+ .id = 204,
+ .asize = RXRPC_APP_MARK_EOF,
+ .name = "CallBack",
+ .user = _SRXAFSCM_CallBack,
+ },
+ {
+ .id = 205,
+ .asize = RXRPC_APP_MARK_EOF,
+ .name = "InitCallBackState",
+ .user = _SRXAFSCM_InitCallBackState,
+ },
+ {
+ .id = 206,
+ .asize = RXRPC_APP_MARK_EOF,
+ .name = "Probe",
+ .user = _SRXAFSCM_Probe,
+ },
+#if 0
+ {
+ .id = 207,
+ .asize = RXRPC_APP_MARK_EOF,
+ .name = "GetLock",
+ .user = _SRXAFSCM_GetLock,
+ },
+ {
+ .id = 208,
+ .asize = RXRPC_APP_MARK_EOF,
+ .name = "GetCE",
+ .user = _SRXAFSCM_GetCE,
+ },
+ {
+ .id = 209,
+ .asize = RXRPC_APP_MARK_EOF,
+ .name = "GetXStatsVersion",
+ .user = _SRXAFSCM_GetXStatsVersion,
+ },
+ {
+ .id = 210,
+ .asize = RXRPC_APP_MARK_EOF,
+ .name = "GetXStats",
+ .user = _SRXAFSCM_GetXStats,
+ }
+#endif
+};
+
+static struct rxrpc_service AFSCM_service = {
+ .name = "AFS/CM",
+ .owner = THIS_MODULE,
+ .link = LIST_HEAD_INIT(AFSCM_service.link),
+ .new_call = afscm_new_call,
+ .service_id = 1,
+ .attn_func = afscm_attention,
+ .error_func = afscm_error,
+ .aemap_func = afscm_aemap,
+ .ops_begin = &AFSCM_ops[0],
+ .ops_end = &AFSCM_ops[sizeof(AFSCM_ops) / sizeof(AFSCM_ops[0])],
+};
+
+static DECLARE_COMPLETION(kafscmd_alive);
+static DECLARE_COMPLETION(kafscmd_dead);
+static DECLARE_WAIT_QUEUE_HEAD(kafscmd_sleepq);
+static LIST_HEAD(kafscmd_attention_list);
+static LIST_HEAD(afscm_calls);
+static DEFINE_SPINLOCK(afscm_calls_lock);
+static DEFINE_SPINLOCK(kafscmd_attention_lock);
+static int kafscmd_die;
+
+/*****************************************************************************/
+/*
+ * AFS Cache Manager kernel thread
+ */
+static int kafscmd(void *arg)
+{
+ DECLARE_WAITQUEUE(myself, current);
+
+ struct rxrpc_call *call;
+ _SRXAFSCM_xxxx_t func;
+ int die;
+
+ printk("kAFS: Started kafscmd %d\n", current->pid);
+
+ daemonize("kafscmd");
+
+ complete(&kafscmd_alive);
+
+ /* loop around looking for things to attend to */
+ do {
+ if (list_empty(&kafscmd_attention_list)) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ add_wait_queue(&kafscmd_sleepq, &myself);
+
+ for (;;) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (!list_empty(&kafscmd_attention_list) ||
+ signal_pending(current) ||
+ kafscmd_die)
+ break;
+
+ schedule();
+ }
+
+ remove_wait_queue(&kafscmd_sleepq, &myself);
+ set_current_state(TASK_RUNNING);
+ }
+
+ die = kafscmd_die;
+
+ /* dequeue the next call requiring attention */
+ call = NULL;
+ spin_lock(&kafscmd_attention_lock);
+
+ if (!list_empty(&kafscmd_attention_list)) {
+ call = list_entry(kafscmd_attention_list.next,
+ struct rxrpc_call,
+ app_attn_link);
+ list_del_init(&call->app_attn_link);
+ die = 0;
+ }
+
+ spin_unlock(&kafscmd_attention_lock);
+
+ if (call) {
+ /* act upon it */
+ _debug("@@@ Begin Attend Call %p", call);
+
+ func = call->app_user;
+ if (func)
+ func(call);
+
+ rxrpc_put_call(call);
+
+ _debug("@@@ End Attend Call %p", call);
+ }
+
+ } while(!die);
+
+ /* and that's all */
+ complete_and_exit(&kafscmd_dead, 0);
+
+} /* end kafscmd() */
+
+/*****************************************************************************/
+/*
+ * handle a call coming in to the cache manager
+ * - if I want to keep the call, I must increment its usage count
+ * - the return value will be negated and passed back in an abort packet if
+ * non-zero
+ * - serialised by virtue of there only being one krxiod
+ */
+static int afscm_new_call(struct rxrpc_call *call)
+{
+ _enter("%p{cid=%u u=%d}",
+ call, ntohl(call->call_id), atomic_read(&call->usage));
+
+ rxrpc_get_call(call);
+
+ /* add to my current call list */
+ spin_lock(&afscm_calls_lock);
+ list_add(&call->app_link,&afscm_calls);
+ spin_unlock(&afscm_calls_lock);
+
+ _leave(" = 0");
+ return 0;
+
+} /* end afscm_new_call() */
+
+/*****************************************************************************/
+/*
+ * queue on the kafscmd queue for attention
+ */
+static void afscm_attention(struct rxrpc_call *call)
+{
+ _enter("%p{cid=%u u=%d}",
+ call, ntohl(call->call_id), atomic_read(&call->usage));
+
+ spin_lock(&kafscmd_attention_lock);
+
+ if (list_empty(&call->app_attn_link)) {
+ list_add_tail(&call->app_attn_link, &kafscmd_attention_list);
+ rxrpc_get_call(call);
+ }
+
+ spin_unlock(&kafscmd_attention_lock);
+
+ wake_up(&kafscmd_sleepq);
+
+ _leave(" {u=%d}", atomic_read(&call->usage));
+} /* end afscm_attention() */
+
+/*****************************************************************************/
+/*
+ * handle my call being aborted
+ * - clean up, dequeue and put my ref to the call
+ */
+static void afscm_error(struct rxrpc_call *call)
+{
+ int removed;
+
+ _enter("%p{est=%s ac=%u er=%d}",
+ call,
+ rxrpc_call_error_states[call->app_err_state],
+ call->app_abort_code,
+ call->app_errno);
+
+ spin_lock(&kafscmd_attention_lock);
+
+ if (list_empty(&call->app_attn_link)) {
+ list_add_tail(&call->app_attn_link, &kafscmd_attention_list);
+ rxrpc_get_call(call);
+ }
+
+ spin_unlock(&kafscmd_attention_lock);
+
+ removed = 0;
+ spin_lock(&afscm_calls_lock);
+ if (!list_empty(&call->app_link)) {
+ list_del_init(&call->app_link);
+ removed = 1;
+ }
+ spin_unlock(&afscm_calls_lock);
+
+ if (removed)
+ rxrpc_put_call(call);
+
+ wake_up(&kafscmd_sleepq);
+
+ _leave("");
+} /* end afscm_error() */
+
+/*****************************************************************************/
+/*
+ * map afs abort codes to/from Linux error codes
+ * - called with call->lock held
+ */
+static void afscm_aemap(struct rxrpc_call *call)
+{
+ switch (call->app_err_state) {
+ case RXRPC_ESTATE_LOCAL_ABORT:
+ call->app_abort_code = -call->app_errno;
+ break;
+ case RXRPC_ESTATE_PEER_ABORT:
+ call->app_errno = -ECONNABORTED;
+ break;
+ default:
+ break;
+ }
+} /* end afscm_aemap() */
+
+/*****************************************************************************/
+/*
+ * start the cache manager service if not already started
+ */
+int afscm_start(void)
+{
+ int ret;
+
+ down_write(&afscm_sem);
+ if (!afscm_usage) {
+ ret = kernel_thread(kafscmd, NULL, 0);
+ if (ret < 0)
+ goto out;
+
+ wait_for_completion(&kafscmd_alive);
+
+ ret = rxrpc_add_service(afs_transport, &AFSCM_service);
+ if (ret < 0)
+ goto kill;
+
+ afs_kafstimod_add_timer(&afs_mntpt_expiry_timer,
+ afs_mntpt_expiry_timeout * HZ);
+ }
+
+ afscm_usage++;
+ up_write(&afscm_sem);
+
+ return 0;
+
+ kill:
+ kafscmd_die = 1;
+ wake_up(&kafscmd_sleepq);
+ wait_for_completion(&kafscmd_dead);
+
+ out:
+ up_write(&afscm_sem);
+ return ret;
+
+} /* end afscm_start() */
+
+/*****************************************************************************/
+/*
+ * stop the cache manager service
+ */
+void afscm_stop(void)
+{
+ struct rxrpc_call *call;
+
+ down_write(&afscm_sem);
+
+ BUG_ON(afscm_usage == 0);
+ afscm_usage--;
+
+ if (afscm_usage == 0) {
+ /* don't want more incoming calls */
+ rxrpc_del_service(afs_transport, &AFSCM_service);
+
+ /* abort any calls I've still got open (the afscm_error() will
+ * dequeue them) */
+ spin_lock(&afscm_calls_lock);
+ while (!list_empty(&afscm_calls)) {
+ call = list_entry(afscm_calls.next,
+ struct rxrpc_call,
+ app_link);
+
+ list_del_init(&call->app_link);
+ rxrpc_get_call(call);
+ spin_unlock(&afscm_calls_lock);
+
+ rxrpc_call_abort(call, -ESRCH); /* abort, dequeue and
+ * put */
+
+ _debug("nuking active call %08x.%d",
+ ntohl(call->conn->conn_id),
+ ntohl(call->call_id));
+ rxrpc_put_call(call);
+ rxrpc_put_call(call);
+
+ spin_lock(&afscm_calls_lock);
+ }
+ spin_unlock(&afscm_calls_lock);
+
+ /* get rid of my daemon */
+ kafscmd_die = 1;
+ wake_up(&kafscmd_sleepq);
+ wait_for_completion(&kafscmd_dead);
+
+ /* dispose of any calls waiting for attention */
+ spin_lock(&kafscmd_attention_lock);
+ while (!list_empty(&kafscmd_attention_list)) {
+ call = list_entry(kafscmd_attention_list.next,
+ struct rxrpc_call,
+ app_attn_link);
+
+ list_del_init(&call->app_attn_link);
+ spin_unlock(&kafscmd_attention_lock);
+
+ rxrpc_put_call(call);
+
+ spin_lock(&kafscmd_attention_lock);
+ }
+ spin_unlock(&kafscmd_attention_lock);
+
+ afs_kafstimod_del_timer(&afs_mntpt_expiry_timer);
+ }
+
+ up_write(&afscm_sem);
+
+} /* end afscm_stop() */
+
+/*****************************************************************************/
+/*
+ * handle the fileserver breaking a set of callbacks
+ */
+static void _SRXAFSCM_CallBack(struct rxrpc_call *call)
+{
+ struct afs_server *server;
+ size_t count, qty, tmp;
+ int ret = 0, removed;
+
+ _enter("%p{acs=%s}", call, rxrpc_call_states[call->app_call_state]);
+
+ server = afs_server_get_from_peer(call->conn->peer);
+
+ switch (call->app_call_state) {
+ /* we've received the last packet
+ * - drain all the data from the call and send the reply
+ */
+ case RXRPC_CSTATE_SRVR_GOT_ARGS:
+ ret = -EBADMSG;
+ qty = call->app_ready_qty;
+ if (qty < 8 || qty > 50 * (6 * 4) + 8)
+ break;
+
+ {
+ struct afs_callback *cb, *pcb;
+ int loop;
+ __be32 *fp, *bp;
+
+ fp = rxrpc_call_alloc_scratch(call, qty);
+
+ /* drag the entire argument block out to the scratch
+ * space */
+ ret = rxrpc_call_read_data(call, fp, qty, 0);
+ if (ret < 0)
+ break;
+
+ /* and unmarshall the parameter block */
+ ret = -EBADMSG;
+ count = ntohl(*fp++);
+ if (count>AFSCBMAX ||
+ (count * (3 * 4) + 8 != qty &&
+ count * (6 * 4) + 8 != qty))
+ break;
+
+ bp = fp + count*3;
+ tmp = ntohl(*bp++);
+ if (tmp > 0 && tmp != count)
+ break;
+ if (tmp == 0)
+ bp = NULL;
+
+ pcb = cb = rxrpc_call_alloc_scratch_s(
+ call, struct afs_callback);
+
+ for (loop = count - 1; loop >= 0; loop--) {
+ pcb->fid.vid = ntohl(*fp++);
+ pcb->fid.vnode = ntohl(*fp++);
+ pcb->fid.unique = ntohl(*fp++);
+ if (bp) {
+ pcb->version = ntohl(*bp++);
+ pcb->expiry = ntohl(*bp++);
+ pcb->type = ntohl(*bp++);
+ }
+ else {
+ pcb->version = 0;
+ pcb->expiry = 0;
+ pcb->type = AFSCM_CB_UNTYPED;
+ }
+ pcb++;
+ }
+
+ /* invoke the actual service routine */
+ ret = SRXAFSCM_CallBack(server, count, cb);
+ if (ret < 0)
+ break;
+ }
+
+ /* send the reply */
+ ret = rxrpc_call_write_data(call, 0, NULL, RXRPC_LAST_PACKET,
+ GFP_KERNEL, 0, &count);
+ if (ret < 0)
+ break;
+ break;
+
+ /* operation complete */
+ case RXRPC_CSTATE_COMPLETE:
+ call->app_user = NULL;
+ removed = 0;
+ spin_lock(&afscm_calls_lock);
+ if (!list_empty(&call->app_link)) {
+ list_del_init(&call->app_link);
+ removed = 1;
+ }
+ spin_unlock(&afscm_calls_lock);
+
+ if (removed)
+ rxrpc_put_call(call);
+ break;
+
+ /* operation terminated on error */
+ case RXRPC_CSTATE_ERROR:
+ call->app_user = NULL;
+ break;
+
+ default:
+ break;
+ }
+
+ if (ret < 0)
+ rxrpc_call_abort(call, ret);
+
+ afs_put_server(server);
+
+ _leave(" = %d", ret);
+
+} /* end _SRXAFSCM_CallBack() */
+
+/*****************************************************************************/
+/*
+ * handle the fileserver asking us to initialise our callback state
+ */
+static void _SRXAFSCM_InitCallBackState(struct rxrpc_call *call)
+{
+ struct afs_server *server;
+ size_t count;
+ int ret = 0, removed;
+
+ _enter("%p{acs=%s}", call, rxrpc_call_states[call->app_call_state]);
+
+ server = afs_server_get_from_peer(call->conn->peer);
+
+ switch (call->app_call_state) {
+ /* we've received the last packet - drain all the data from the
+ * call */
+ case RXRPC_CSTATE_SRVR_GOT_ARGS:
+ /* shouldn't be any args */
+ ret = -EBADMSG;
+ break;
+
+ /* send the reply when asked for it */
+ case RXRPC_CSTATE_SRVR_SND_REPLY:
+ /* invoke the actual service routine */
+ ret = SRXAFSCM_InitCallBackState(server);
+ if (ret < 0)
+ break;
+
+ ret = rxrpc_call_write_data(call, 0, NULL, RXRPC_LAST_PACKET,
+ GFP_KERNEL, 0, &count);
+ if (ret < 0)
+ break;
+ break;
+
+ /* operation complete */
+ case RXRPC_CSTATE_COMPLETE:
+ call->app_user = NULL;
+ removed = 0;
+ spin_lock(&afscm_calls_lock);
+ if (!list_empty(&call->app_link)) {
+ list_del_init(&call->app_link);
+ removed = 1;
+ }
+ spin_unlock(&afscm_calls_lock);
+
+ if (removed)
+ rxrpc_put_call(call);
+ break;
+
+ /* operation terminated on error */
+ case RXRPC_CSTATE_ERROR:
+ call->app_user = NULL;
+ break;
+
+ default:
+ break;
+ }
+
+ if (ret < 0)
+ rxrpc_call_abort(call, ret);
+
+ afs_put_server(server);
+
+ _leave(" = %d", ret);
+
+} /* end _SRXAFSCM_InitCallBackState() */
+
+/*****************************************************************************/
+/*
+ * handle a probe from a fileserver
+ */
+static void _SRXAFSCM_Probe(struct rxrpc_call *call)
+{
+ struct afs_server *server;
+ size_t count;
+ int ret = 0, removed;
+
+ _enter("%p{acs=%s}", call, rxrpc_call_states[call->app_call_state]);
+
+ server = afs_server_get_from_peer(call->conn->peer);
+
+ switch (call->app_call_state) {
+ /* we've received the last packet - drain all the data from the
+ * call */
+ case RXRPC_CSTATE_SRVR_GOT_ARGS:
+ /* shouldn't be any args */
+ ret = -EBADMSG;
+ break;
+
+ /* send the reply when asked for it */
+ case RXRPC_CSTATE_SRVR_SND_REPLY:
+ /* invoke the actual service routine */
+ ret = SRXAFSCM_Probe(server);
+ if (ret < 0)
+ break;
+
+ ret = rxrpc_call_write_data(call, 0, NULL, RXRPC_LAST_PACKET,
+ GFP_KERNEL, 0, &count);
+ if (ret < 0)
+ break;
+ break;
+
+ /* operation complete */
+ case RXRPC_CSTATE_COMPLETE:
+ call->app_user = NULL;
+ removed = 0;
+ spin_lock(&afscm_calls_lock);
+ if (!list_empty(&call->app_link)) {
+ list_del_init(&call->app_link);
+ removed = 1;
+ }
+ spin_unlock(&afscm_calls_lock);
+
+ if (removed)
+ rxrpc_put_call(call);
+ break;
+
+ /* operation terminated on error */
+ case RXRPC_CSTATE_ERROR:
+ call->app_user = NULL;
+ break;
+
+ default:
+ break;
+ }
+
+ if (ret < 0)
+ rxrpc_call_abort(call, ret);
+
+ afs_put_server(server);
+
+ _leave(" = %d", ret);
+
+} /* end _SRXAFSCM_Probe() */
OpenPOWER on IntegriCloud