diff options
Diffstat (limited to 'fs/afs/cmservice.c')
-rw-r--r-- | fs/afs/cmservice.c | 652 |
1 files changed, 652 insertions, 0 deletions
diff --git a/fs/afs/cmservice.c b/fs/afs/cmservice.c new file mode 100644 index 00000000000..0a57fd7c726 --- /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() */ |