Import 2.3.26pre2

[davej-history.git] / fs / lockd / svcproc.c

/*
 * linux/fs/lockd/svcproc.c
 *
 * Lockd server procedures. We don't implement the NLM_*_RES 
 * procedures because we don't use the async procedures.
 *
 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/types.h>
#include <linux/sched.h>
#include <linux/malloc.h>
#include <linux/in.h>
#include <linux/sunrpc/svc.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfsd/nfsd.h>
#include <linux/lockd/lockd.h>
#include <linux/lockd/share.h>
#include <linux/lockd/sm_inter.h>


#define NLMDBG_FACILITY         NLMDBG_CLIENT

static u32      nlmsvc_callback(struct svc_rqst *, u32, struct nlm_res *);
static void     nlmsvc_callback_exit(struct rpc_task *);

/*
 * Obtain client and file from arguments
 */
static u32
nlmsvc_retrieve_args(struct svc_rqst *rqstp, struct nlm_args *argp,
                        struct nlm_host **hostp, struct nlm_file **filp)
{
        struct nlm_host         *host = NULL;
        struct nlm_file         *file = NULL;
        struct nlm_lock         *lock = &argp->lock;
        u32                     error;

        /* nfsd callbacks must have been installed for this procedure */
        if (!nlmsvc_ops)
                return nlm_lck_denied_nolocks;

        /* Obtain handle for client host */
        if (rqstp->rq_client == NULL) {
                printk(KERN_NOTICE
                        "lockd: unauthenticated request from (%08lx:%d)\n",
                        ntohl(rqstp->rq_addr.sin_addr.s_addr),
                        ntohs(rqstp->rq_addr.sin_port));
                return nlm_lck_denied_nolocks;
        }

        /* Obtain host handle */
        if (!(host = nlmsvc_lookup_host(rqstp))
         || (argp->monitor && !host->h_monitored && nsm_monitor(host) < 0))
                goto no_locks;
        *hostp = host;

        /* Obtain file pointer. Not used by FREE_ALL call. */
        if (filp != NULL) {
                if ((error = nlm_lookup_file(rqstp, &file, &lock->fh)) != 0)
                        goto no_locks;
                *filp = file;

                /* Set up the missing parts of the file_lock structure */
                lock->fl.fl_file  = &file->f_file;
                lock->fl.fl_owner = (fl_owner_t) host;
        }

        return 0;

no_locks:
        if (host)
                nlm_release_host(host);
        return nlm_lck_denied_nolocks;
}

/*
 * NULL: Test for presence of service
 */
static int
nlmsvc_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
{
        dprintk("lockd: NULL          called\n");
        return rpc_success;
}

/*
 * TEST: Check for conflicting lock
 */
static int
nlmsvc_proc_test(struct svc_rqst *rqstp, struct nlm_args *argp,
                                         struct nlm_res  *resp)
{
        struct nlm_host *host;
        struct nlm_file *file;

        dprintk("lockd: TEST          called\n");
        resp->cookie = argp->cookie;

        /* Don't accept test requests during grace period */
        if (nlmsvc_grace_period) {
                resp->status = nlm_lck_denied_grace_period;
                return rpc_success;
        }

        /* Obtain client and file */
        if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
                return rpc_success;

        /* Now check for conflicting locks */
        resp->status = nlmsvc_testlock(file, &argp->lock, &resp->lock);

        dprintk("lockd: TEST          status %ld\n", ntohl(resp->status));
        nlm_release_host(host);
        nlm_release_file(file);
        return rpc_success;
}

static int
nlmsvc_proc_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
                                         struct nlm_res  *resp)
{
        struct nlm_host *host;
        struct nlm_file *file;

        dprintk("lockd: LOCK          called\n");

        resp->cookie = argp->cookie;

        /* Don't accept new lock requests during grace period */
        if (nlmsvc_grace_period && !argp->reclaim) {
                resp->status = nlm_lck_denied_grace_period;
                return rpc_success;
        }

        /* Obtain client and file */
        if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
                return rpc_success;

#if 0
        /* If supplied state doesn't match current state, we assume it's
         * an old request that time-warped somehow. Any error return would
         * do in this case because it's irrelevant anyway.
         *
         * NB: We don't retrieve the remote host's state yet.
         */
        if (host->h_nsmstate && host->h_nsmstate != argp->state) {
                resp->status = nlm_lck_denied_nolocks;
        } else
#endif

        /* Now try to lock the file */
        resp->status = nlmsvc_lock(rqstp, file, &argp->lock,
                                        argp->block, &argp->cookie);

        dprintk("lockd: LOCK          status %ld\n", ntohl(resp->status));
        nlm_release_host(host);
        nlm_release_file(file);
        return rpc_success;
}

static int
nlmsvc_proc_cancel(struct svc_rqst *rqstp, struct nlm_args *argp,
                                           struct nlm_res  *resp)
{
        struct nlm_host *host;
        struct nlm_file *file;

        dprintk("lockd: CANCEL        called\n");

        resp->cookie = argp->cookie;

        /* Don't accept requests during grace period */
        if (nlmsvc_grace_period) {
                resp->status = nlm_lck_denied_grace_period;
                return rpc_success;
        }

        /* Obtain client and file */
        if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
                return rpc_success;

        /* Try to cancel request. */
        resp->status = nlmsvc_cancel_blocked(file, &argp->lock);

        dprintk("lockd: CANCEL        status %ld\n", ntohl(resp->status));
        nlm_release_host(host);
        nlm_release_file(file);
        return rpc_success;
}

/*
 * UNLOCK: release a lock
 */
static int
nlmsvc_proc_unlock(struct svc_rqst *rqstp, struct nlm_args *argp,
                                           struct nlm_res  *resp)
{
        struct nlm_host *host;
        struct nlm_file *file;

        dprintk("lockd: UNLOCK        called\n");

        resp->cookie = argp->cookie;

        /* Don't accept new lock requests during grace period */
        if (nlmsvc_grace_period) {
                resp->status = nlm_lck_denied_grace_period;
                return rpc_success;
        }

        /* Obtain client and file */
        if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
                return rpc_success;

        /* Now try to remove the lock */
        resp->status = nlmsvc_unlock(file, &argp->lock);

        dprintk("lockd: UNLOCK        status %ld\n", ntohl(resp->status));
        nlm_release_host(host);
        nlm_release_file(file);
        return rpc_success;
}

/*
 * GRANTED: A server calls us to tell that a process' lock request
 * was granted
 */
static int
nlmsvc_proc_granted(struct svc_rqst *rqstp, struct nlm_args *argp,
                                            struct nlm_res  *resp)
{
        resp->cookie = argp->cookie;

        dprintk("lockd: GRANTED       called\n");
        resp->status = nlmclnt_grant(&argp->lock);
        dprintk("lockd: GRANTED       status %ld\n", ntohl(resp->status));
        return rpc_success;
}

/*
 * `Async' versions of the above service routines. They aren't really,
 * because we send the callback before the reply proper. I hope this
 * doesn't break any clients.
 */
static int
nlmsvc_proc_test_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
                                             void            *resp)
{
        struct nlm_res  res;
        u32             stat;

        dprintk("lockd: TEST_MSG      called\n");

        if ((stat = nlmsvc_proc_test(rqstp, argp, &res)) == 0)
                stat = nlmsvc_callback(rqstp, NLMPROC_TEST_RES, &res);
        return stat;
}

static int
nlmsvc_proc_lock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
                                             void            *resp)
{
        struct nlm_res  res;
        u32             stat;

        dprintk("lockd: LOCK_MSG      called\n");

        if ((stat = nlmsvc_proc_lock(rqstp, argp, &res)) == 0)
                stat = nlmsvc_callback(rqstp, NLMPROC_LOCK_RES, &res);
        return stat;
}

static int
nlmsvc_proc_cancel_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
                                               void            *resp)
{
        struct nlm_res  res;
        u32             stat;

        dprintk("lockd: CANCEL_MSG    called\n");

        if ((stat = nlmsvc_proc_cancel(rqstp, argp, &res)) == 0)
                stat = nlmsvc_callback(rqstp, NLMPROC_CANCEL_RES, &res);
        return stat;
}

static int
nlmsvc_proc_unlock_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
                                               void            *resp)
{
        struct nlm_res  res;
        u32             stat;

        dprintk("lockd: UNLOCK_MSG    called\n");

        if ((stat = nlmsvc_proc_unlock(rqstp, argp, &res)) == 0)
                stat = nlmsvc_callback(rqstp, NLMPROC_UNLOCK_RES, &res);
        return stat;
}

static int
nlmsvc_proc_granted_msg(struct svc_rqst *rqstp, struct nlm_args *argp,
                                                void            *resp)
{
        struct nlm_res  res;
        u32             stat;

        dprintk("lockd: GRANTED_MSG   called\n");

        if ((stat = nlmsvc_proc_granted(rqstp, argp, &res)) == 0)
                stat = nlmsvc_callback(rqstp, NLMPROC_GRANTED_RES, &res);
        return stat;
}

/*
 * SHARE: create a DOS share or alter existing share.
 */
static int
nlmsvc_proc_share(struct svc_rqst *rqstp, struct nlm_args *argp,
                                          struct nlm_res  *resp)
{
        struct nlm_host *host;
        struct nlm_file *file;

        dprintk("lockd: SHARE         called\n");

        resp->cookie = argp->cookie;

        /* Don't accept new lock requests during grace period */
        if (nlmsvc_grace_period && !argp->reclaim) {
                resp->status = nlm_lck_denied_grace_period;
                return rpc_success;
        }

        /* Obtain client and file */
        if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
                return rpc_success;

        /* Now try to create the share */
        resp->status = nlmsvc_share_file(host, file, argp);

        dprintk("lockd: SHARE         status %ld\n", ntohl(resp->status));
        nlm_release_host(host);
        nlm_release_file(file);
        return rpc_success;
}

/*
 * UNSHARE: Release a DOS share.
 */
static int
nlmsvc_proc_unshare(struct svc_rqst *rqstp, struct nlm_args *argp,
                                            struct nlm_res  *resp)
{
        struct nlm_host *host;
        struct nlm_file *file;

        dprintk("lockd: UNSHARE       called\n");

        resp->cookie = argp->cookie;

        /* Don't accept requests during grace period */
        if (nlmsvc_grace_period) {
                resp->status = nlm_lck_denied_grace_period;
                return rpc_success;
        }

        /* Obtain client and file */
        if ((resp->status = nlmsvc_retrieve_args(rqstp, argp, &host, &file)))
                return rpc_success;

        /* Now try to lock the file */
        resp->status = nlmsvc_unshare_file(host, file, argp);

        dprintk("lockd: UNSHARE       status %ld\n", ntohl(resp->status));
        nlm_release_host(host);
        nlm_release_file(file);
        return rpc_success;
}

/*
 * NM_LOCK: Create an unmonitored lock
 */
static int
nlmsvc_proc_nm_lock(struct svc_rqst *rqstp, struct nlm_args *argp,
                                            struct nlm_res  *resp)
{
        dprintk("lockd: NM_LOCK       called\n");

        argp->monitor = 0;              /* just clean the monitor flag */
        return nlmsvc_proc_lock(rqstp, argp, resp);
}

/*
 * FREE_ALL: Release all locks and shares held by client
 */
static int
nlmsvc_proc_free_all(struct svc_rqst *rqstp, struct nlm_args *argp,
                                             void            *resp)
{
        struct nlm_host *host;

        /* Obtain client */
        if (nlmsvc_retrieve_args(rqstp, argp, &host, NULL))
                return rpc_success;

        nlmsvc_free_host_resources(host);
        nlm_release_host(host);
        return rpc_success;
}

/*
 * SM_NOTIFY: private callback from statd (not part of official NLM proto)
 */
static int
nlmsvc_proc_sm_notify(struct svc_rqst *rqstp, struct nlm_reboot *argp,
                                              void              *resp)
{
        struct sockaddr_in      saddr = rqstp->rq_addr;
        struct nlm_host         *host;

        dprintk("lockd: SM_NOTIFY     called\n");
        if (saddr.sin_addr.s_addr != htonl(INADDR_LOOPBACK)
         || ntohs(saddr.sin_port) >= 1024) {
                printk(KERN_WARNING
                        "lockd: rejected NSM callback from %08lx:%d\n",
                        ntohl(rqstp->rq_addr.sin_addr.s_addr),
                        ntohs(rqstp->rq_addr.sin_port));
                return rpc_system_err;
        }

        /* Obtain the host pointer for this NFS server and try to
         * reclaim all locks we hold on this server.
         */
        saddr.sin_addr.s_addr = argp->addr;     
        if ((host = nlm_lookup_host(NULL, &saddr, IPPROTO_UDP, 1)) != NULL) {
                nlmclnt_recovery(host, argp->state);
                nlm_release_host(host);
        }

        /* If we run on an NFS server, delete all locks held by the client */
        if (nlmsvc_ops != NULL) {
                struct svc_client       *clnt;
                saddr.sin_addr.s_addr = argp->addr;     
                if ((clnt = nlmsvc_ops->exp_getclient(&saddr)) != NULL 
                 && (host = nlm_lookup_host(clnt, &saddr, 0, 0)) != NULL) {
                        nlmsvc_free_host_resources(host);
                }
                nlm_release_host(host);
        }

        return rpc_success;
}

/*
 * This is the generic lockd callback for async RPC calls
 */
static u32
nlmsvc_callback(struct svc_rqst *rqstp, u32 proc, struct nlm_res *resp)
{
        struct nlm_host *host;
        struct nlm_rqst *call;

        if (!(call = nlmclnt_alloc_call()))
                return rpc_system_err;

        host = nlmclnt_lookup_host(&rqstp->rq_addr,
                                rqstp->rq_prot, rqstp->rq_vers);
        if (!host) {
                kfree(call);
                return rpc_system_err;
        }

        call->a_flags = RPC_TASK_ASYNC;
        call->a_host  = host;
        memcpy(&call->a_args, resp, sizeof(*resp));

        if (nlmclnt_async_call(call, proc, nlmsvc_callback_exit) < 0)
                return rpc_system_err;

        return rpc_success;
}

static void
nlmsvc_callback_exit(struct rpc_task *task)
{
        struct nlm_rqst *call = (struct nlm_rqst *) task->tk_calldata;

        if (task->tk_status < 0) {
                dprintk("lockd: %4d callback failed (errno = %d)\n",
                                        task->tk_pid, -task->tk_status);
        }
        nlm_release_host(call->a_host);
        rpc_release_task(task);
        kfree(call);
}

/*
 * NLM Server procedures.
 */

#define nlmsvc_encode_norep     nlmsvc_encode_void
#define nlmsvc_decode_norep     nlmsvc_decode_void
#define nlmsvc_decode_testres   nlmsvc_decode_void
#define nlmsvc_decode_lockres   nlmsvc_decode_void
#define nlmsvc_decode_unlockres nlmsvc_decode_void
#define nlmsvc_decode_cancelres nlmsvc_decode_void
#define nlmsvc_decode_grantedres        nlmsvc_decode_void

#define nlmsvc_proc_none        nlmsvc_proc_null
#define nlmsvc_proc_test_res    nlmsvc_proc_null
#define nlmsvc_proc_lock_res    nlmsvc_proc_null
#define nlmsvc_proc_cancel_res  nlmsvc_proc_null
#define nlmsvc_proc_unlock_res  nlmsvc_proc_null
#define nlmsvc_proc_granted_res nlmsvc_proc_null

struct nlm_void                 { int dummy; };

#define PROC(name, xargt, xrest, argt, rest)    \
 { (svc_procfunc) nlmsvc_proc_##name,   \
   (kxdrproc_t) nlmsvc_decode_##xargt,  \
   (kxdrproc_t) nlmsvc_encode_##xrest,  \
   NULL,                                \
   sizeof(struct nlm_##argt),           \
   sizeof(struct nlm_##rest),           \
   0,                                   \
   0                                    \
 }
struct svc_procedure            nlmsvc_procedures[] = {
  PROC(null,            void,           void,           void,   void),
  PROC(test,            testargs,       testres,        args,   res),
  PROC(lock,            lockargs,       res,            args,   res),
  PROC(cancel,          cancargs,       res,            args,   res),
  PROC(unlock,          unlockargs,     res,            args,   res),
  PROC(granted,         testargs,       res,            args,   res),
  PROC(test_msg,        testargs,       norep,          args,   void),
  PROC(lock_msg,        lockargs,       norep,          args,   void),
  PROC(cancel_msg,      cancargs,       norep,          args,   void),
  PROC(unlock_msg,      unlockargs,     norep,          args,   void),
  PROC(granted_msg,     testargs,       norep,          args,   void),
  PROC(test_res,        testres,        norep,          res,    void),
  PROC(lock_res,        lockres,        norep,          res,    void),
  PROC(cancel_res,      cancelres,      norep,          res,    void),
  PROC(unlock_res,      unlockres,      norep,          res,    void),
  PROC(granted_res,     grantedres,     norep,          res,    void),
  PROC(none,            void,           void,           void,   void),
  PROC(none,            void,           void,           void,   void),
  PROC(none,            void,           void,           void,   void),
  PROC(none,            void,           void,           void,   void),
  PROC(share,           shareargs,      shareres,       args,   res),
  PROC(unshare,         shareargs,      shareres,       args,   res),
  PROC(nm_lock,         lockargs,       res,            args,   res),
  PROC(free_all,        notify,         void,           args,   void),

  /* statd callback */
  PROC(sm_notify,       reboot,         void,           reboot, void),
};