Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/fs/lockd/clntproc.c b/fs/lockd/clntproc.c
new file mode 100644
index 0000000..a440761
--- /dev/null
+++ b/fs/lockd/clntproc.c
@@ -0,0 +1,820 @@
+/*
+ * linux/fs/lockd/clntproc.c
+ *
+ * RPC procedures for the client side NLM implementation
+ *
+ * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/nfs_fs.h>
+#include <linux/utsname.h>
+#include <linux/smp_lock.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/svc.h>
+#include <linux/lockd/lockd.h>
+#include <linux/lockd/sm_inter.h>
+
+#define NLMDBG_FACILITY NLMDBG_CLIENT
+#define NLMCLNT_GRACE_WAIT (5*HZ)
+
+static int nlmclnt_test(struct nlm_rqst *, struct file_lock *);
+static int nlmclnt_lock(struct nlm_rqst *, struct file_lock *);
+static int nlmclnt_unlock(struct nlm_rqst *, struct file_lock *);
+static void nlmclnt_unlock_callback(struct rpc_task *);
+static void nlmclnt_cancel_callback(struct rpc_task *);
+static int nlm_stat_to_errno(u32 stat);
+static void nlmclnt_locks_init_private(struct file_lock *fl, struct nlm_host *host);
+
+/*
+ * Cookie counter for NLM requests
+ */
+static u32 nlm_cookie = 0x1234;
+
+static inline void nlmclnt_next_cookie(struct nlm_cookie *c)
+{
+ memcpy(c->data, &nlm_cookie, 4);
+ memset(c->data+4, 0, 4);
+ c->len=4;
+ nlm_cookie++;
+}
+
+static struct nlm_lockowner *nlm_get_lockowner(struct nlm_lockowner *lockowner)
+{
+ atomic_inc(&lockowner->count);
+ return lockowner;
+}
+
+static void nlm_put_lockowner(struct nlm_lockowner *lockowner)
+{
+ if (!atomic_dec_and_lock(&lockowner->count, &lockowner->host->h_lock))
+ return;
+ list_del(&lockowner->list);
+ spin_unlock(&lockowner->host->h_lock);
+ nlm_release_host(lockowner->host);
+ kfree(lockowner);
+}
+
+static inline int nlm_pidbusy(struct nlm_host *host, uint32_t pid)
+{
+ struct nlm_lockowner *lockowner;
+ list_for_each_entry(lockowner, &host->h_lockowners, list) {
+ if (lockowner->pid == pid)
+ return -EBUSY;
+ }
+ return 0;
+}
+
+static inline uint32_t __nlm_alloc_pid(struct nlm_host *host)
+{
+ uint32_t res;
+ do {
+ res = host->h_pidcount++;
+ } while (nlm_pidbusy(host, res) < 0);
+ return res;
+}
+
+static struct nlm_lockowner *__nlm_find_lockowner(struct nlm_host *host, fl_owner_t owner)
+{
+ struct nlm_lockowner *lockowner;
+ list_for_each_entry(lockowner, &host->h_lockowners, list) {
+ if (lockowner->owner != owner)
+ continue;
+ return nlm_get_lockowner(lockowner);
+ }
+ return NULL;
+}
+
+static struct nlm_lockowner *nlm_find_lockowner(struct nlm_host *host, fl_owner_t owner)
+{
+ struct nlm_lockowner *res, *new = NULL;
+
+ spin_lock(&host->h_lock);
+ res = __nlm_find_lockowner(host, owner);
+ if (res == NULL) {
+ spin_unlock(&host->h_lock);
+ new = (struct nlm_lockowner *)kmalloc(sizeof(*new), GFP_KERNEL);
+ spin_lock(&host->h_lock);
+ res = __nlm_find_lockowner(host, owner);
+ if (res == NULL && new != NULL) {
+ res = new;
+ atomic_set(&new->count, 1);
+ new->owner = owner;
+ new->pid = __nlm_alloc_pid(host);
+ new->host = nlm_get_host(host);
+ list_add(&new->list, &host->h_lockowners);
+ new = NULL;
+ }
+ }
+ spin_unlock(&host->h_lock);
+ if (new != NULL)
+ kfree(new);
+ return res;
+}
+
+/*
+ * Initialize arguments for TEST/LOCK/UNLOCK/CANCEL calls
+ */
+static void nlmclnt_setlockargs(struct nlm_rqst *req, struct file_lock *fl)
+{
+ struct nlm_args *argp = &req->a_args;
+ struct nlm_lock *lock = &argp->lock;
+
+ nlmclnt_next_cookie(&argp->cookie);
+ argp->state = nsm_local_state;
+ memcpy(&lock->fh, NFS_FH(fl->fl_file->f_dentry->d_inode), sizeof(struct nfs_fh));
+ lock->caller = system_utsname.nodename;
+ lock->oh.data = req->a_owner;
+ lock->oh.len = sprintf(req->a_owner, "%d@%s",
+ current->pid, system_utsname.nodename);
+ locks_copy_lock(&lock->fl, fl);
+}
+
+static void nlmclnt_release_lockargs(struct nlm_rqst *req)
+{
+ struct file_lock *fl = &req->a_args.lock.fl;
+
+ if (fl->fl_ops && fl->fl_ops->fl_release_private)
+ fl->fl_ops->fl_release_private(fl);
+}
+
+/*
+ * Initialize arguments for GRANTED call. The nlm_rqst structure
+ * has been cleared already.
+ */
+int
+nlmclnt_setgrantargs(struct nlm_rqst *call, struct nlm_lock *lock)
+{
+ locks_copy_lock(&call->a_args.lock.fl, &lock->fl);
+ memcpy(&call->a_args.lock.fh, &lock->fh, sizeof(call->a_args.lock.fh));
+ call->a_args.lock.caller = system_utsname.nodename;
+ call->a_args.lock.oh.len = lock->oh.len;
+
+ /* set default data area */
+ call->a_args.lock.oh.data = call->a_owner;
+
+ if (lock->oh.len > NLMCLNT_OHSIZE) {
+ void *data = kmalloc(lock->oh.len, GFP_KERNEL);
+ if (!data) {
+ nlmclnt_freegrantargs(call);
+ return 0;
+ }
+ call->a_args.lock.oh.data = (u8 *) data;
+ }
+
+ memcpy(call->a_args.lock.oh.data, lock->oh.data, lock->oh.len);
+ return 1;
+}
+
+void
+nlmclnt_freegrantargs(struct nlm_rqst *call)
+{
+ struct file_lock *fl = &call->a_args.lock.fl;
+ /*
+ * Check whether we allocated memory for the owner.
+ */
+ if (call->a_args.lock.oh.data != (u8 *) call->a_owner) {
+ kfree(call->a_args.lock.oh.data);
+ }
+ if (fl->fl_ops && fl->fl_ops->fl_release_private)
+ fl->fl_ops->fl_release_private(fl);
+}
+
+/*
+ * This is the main entry point for the NLM client.
+ */
+int
+nlmclnt_proc(struct inode *inode, int cmd, struct file_lock *fl)
+{
+ struct nfs_server *nfssrv = NFS_SERVER(inode);
+ struct nlm_host *host;
+ struct nlm_rqst reqst, *call = &reqst;
+ sigset_t oldset;
+ unsigned long flags;
+ int status, proto, vers;
+
+ vers = (NFS_PROTO(inode)->version == 3) ? 4 : 1;
+ if (NFS_PROTO(inode)->version > 3) {
+ printk(KERN_NOTICE "NFSv4 file locking not implemented!\n");
+ return -ENOLCK;
+ }
+
+ /* Retrieve transport protocol from NFS client */
+ proto = NFS_CLIENT(inode)->cl_xprt->prot;
+
+ if (!(host = nlmclnt_lookup_host(NFS_ADDR(inode), proto, vers)))
+ return -ENOLCK;
+
+ /* Create RPC client handle if not there, and copy soft
+ * and intr flags from NFS client. */
+ if (host->h_rpcclnt == NULL) {
+ struct rpc_clnt *clnt;
+
+ /* Bind an rpc client to this host handle (does not
+ * perform a portmapper lookup) */
+ if (!(clnt = nlm_bind_host(host))) {
+ status = -ENOLCK;
+ goto done;
+ }
+ clnt->cl_softrtry = nfssrv->client->cl_softrtry;
+ clnt->cl_intr = nfssrv->client->cl_intr;
+ clnt->cl_chatty = nfssrv->client->cl_chatty;
+ }
+
+ /* Keep the old signal mask */
+ spin_lock_irqsave(¤t->sighand->siglock, flags);
+ oldset = current->blocked;
+
+ /* If we're cleaning up locks because the process is exiting,
+ * perform the RPC call asynchronously. */
+ if ((IS_SETLK(cmd) || IS_SETLKW(cmd))
+ && fl->fl_type == F_UNLCK
+ && (current->flags & PF_EXITING)) {
+ sigfillset(¤t->blocked); /* Mask all signals */
+ recalc_sigpending();
+ spin_unlock_irqrestore(¤t->sighand->siglock, flags);
+
+ call = nlmclnt_alloc_call();
+ if (!call) {
+ status = -ENOMEM;
+ goto out_restore;
+ }
+ call->a_flags = RPC_TASK_ASYNC;
+ } else {
+ spin_unlock_irqrestore(¤t->sighand->siglock, flags);
+ memset(call, 0, sizeof(*call));
+ locks_init_lock(&call->a_args.lock.fl);
+ locks_init_lock(&call->a_res.lock.fl);
+ }
+ call->a_host = host;
+
+ nlmclnt_locks_init_private(fl, host);
+
+ /* Set up the argument struct */
+ nlmclnt_setlockargs(call, fl);
+
+ if (IS_SETLK(cmd) || IS_SETLKW(cmd)) {
+ if (fl->fl_type != F_UNLCK) {
+ call->a_args.block = IS_SETLKW(cmd) ? 1 : 0;
+ status = nlmclnt_lock(call, fl);
+ } else
+ status = nlmclnt_unlock(call, fl);
+ } else if (IS_GETLK(cmd))
+ status = nlmclnt_test(call, fl);
+ else
+ status = -EINVAL;
+
+ out_restore:
+ spin_lock_irqsave(¤t->sighand->siglock, flags);
+ current->blocked = oldset;
+ recalc_sigpending();
+ spin_unlock_irqrestore(¤t->sighand->siglock, flags);
+
+done:
+ dprintk("lockd: clnt proc returns %d\n", status);
+ nlm_release_host(host);
+ return status;
+}
+EXPORT_SYMBOL(nlmclnt_proc);
+
+/*
+ * Allocate an NLM RPC call struct
+ */
+struct nlm_rqst *
+nlmclnt_alloc_call(void)
+{
+ struct nlm_rqst *call;
+
+ while (!signalled()) {
+ call = (struct nlm_rqst *) kmalloc(sizeof(struct nlm_rqst), GFP_KERNEL);
+ if (call) {
+ memset(call, 0, sizeof(*call));
+ locks_init_lock(&call->a_args.lock.fl);
+ locks_init_lock(&call->a_res.lock.fl);
+ return call;
+ }
+ printk("nlmclnt_alloc_call: failed, waiting for memory\n");
+ current->state = TASK_INTERRUPTIBLE;
+ schedule_timeout(5*HZ);
+ }
+ return NULL;
+}
+
+static int nlm_wait_on_grace(wait_queue_head_t *queue)
+{
+ DEFINE_WAIT(wait);
+ int status = -EINTR;
+
+ prepare_to_wait(queue, &wait, TASK_INTERRUPTIBLE);
+ if (!signalled ()) {
+ schedule_timeout(NLMCLNT_GRACE_WAIT);
+ try_to_freeze(PF_FREEZE);
+ if (!signalled ())
+ status = 0;
+ }
+ finish_wait(queue, &wait);
+ return status;
+}
+
+/*
+ * Generic NLM call
+ */
+static int
+nlmclnt_call(struct nlm_rqst *req, u32 proc)
+{
+ struct nlm_host *host = req->a_host;
+ struct rpc_clnt *clnt;
+ struct nlm_args *argp = &req->a_args;
+ struct nlm_res *resp = &req->a_res;
+ struct rpc_message msg = {
+ .rpc_argp = argp,
+ .rpc_resp = resp,
+ };
+ int status;
+
+ dprintk("lockd: call procedure %d on %s\n",
+ (int)proc, host->h_name);
+
+ do {
+ if (host->h_reclaiming && !argp->reclaim)
+ goto in_grace_period;
+
+ /* If we have no RPC client yet, create one. */
+ if ((clnt = nlm_bind_host(host)) == NULL)
+ return -ENOLCK;
+ msg.rpc_proc = &clnt->cl_procinfo[proc];
+
+ /* Perform the RPC call. If an error occurs, try again */
+ if ((status = rpc_call_sync(clnt, &msg, 0)) < 0) {
+ dprintk("lockd: rpc_call returned error %d\n", -status);
+ switch (status) {
+ case -EPROTONOSUPPORT:
+ status = -EINVAL;
+ break;
+ case -ECONNREFUSED:
+ case -ETIMEDOUT:
+ case -ENOTCONN:
+ nlm_rebind_host(host);
+ status = -EAGAIN;
+ break;
+ case -ERESTARTSYS:
+ return signalled () ? -EINTR : status;
+ default:
+ break;
+ }
+ break;
+ } else
+ if (resp->status == NLM_LCK_DENIED_GRACE_PERIOD) {
+ dprintk("lockd: server in grace period\n");
+ if (argp->reclaim) {
+ printk(KERN_WARNING
+ "lockd: spurious grace period reject?!\n");
+ return -ENOLCK;
+ }
+ } else {
+ if (!argp->reclaim) {
+ /* We appear to be out of the grace period */
+ wake_up_all(&host->h_gracewait);
+ }
+ dprintk("lockd: server returns status %d\n", resp->status);
+ return 0; /* Okay, call complete */
+ }
+
+in_grace_period:
+ /*
+ * The server has rebooted and appears to be in the grace
+ * period during which locks are only allowed to be
+ * reclaimed.
+ * We can only back off and try again later.
+ */
+ status = nlm_wait_on_grace(&host->h_gracewait);
+ } while (status == 0);
+
+ return status;
+}
+
+/*
+ * Generic NLM call, async version.
+ */
+int
+nlmsvc_async_call(struct nlm_rqst *req, u32 proc, rpc_action callback)
+{
+ struct nlm_host *host = req->a_host;
+ struct rpc_clnt *clnt;
+ struct rpc_message msg = {
+ .rpc_argp = &req->a_args,
+ .rpc_resp = &req->a_res,
+ };
+ int status;
+
+ dprintk("lockd: call procedure %d on %s (async)\n",
+ (int)proc, host->h_name);
+
+ /* If we have no RPC client yet, create one. */
+ if ((clnt = nlm_bind_host(host)) == NULL)
+ return -ENOLCK;
+ msg.rpc_proc = &clnt->cl_procinfo[proc];
+
+ /* bootstrap and kick off the async RPC call */
+ status = rpc_call_async(clnt, &msg, RPC_TASK_ASYNC, callback, req);
+
+ return status;
+}
+
+static int
+nlmclnt_async_call(struct nlm_rqst *req, u32 proc, rpc_action callback)
+{
+ struct nlm_host *host = req->a_host;
+ struct rpc_clnt *clnt;
+ struct nlm_args *argp = &req->a_args;
+ struct nlm_res *resp = &req->a_res;
+ struct rpc_message msg = {
+ .rpc_argp = argp,
+ .rpc_resp = resp,
+ };
+ int status;
+
+ dprintk("lockd: call procedure %d on %s (async)\n",
+ (int)proc, host->h_name);
+
+ /* If we have no RPC client yet, create one. */
+ if ((clnt = nlm_bind_host(host)) == NULL)
+ return -ENOLCK;
+ msg.rpc_proc = &clnt->cl_procinfo[proc];
+
+ /* Increment host refcount */
+ nlm_get_host(host);
+ /* bootstrap and kick off the async RPC call */
+ status = rpc_call_async(clnt, &msg, RPC_TASK_ASYNC, callback, req);
+ if (status < 0)
+ nlm_release_host(host);
+ return status;
+}
+
+/*
+ * TEST for the presence of a conflicting lock
+ */
+static int
+nlmclnt_test(struct nlm_rqst *req, struct file_lock *fl)
+{
+ int status;
+
+ status = nlmclnt_call(req, NLMPROC_TEST);
+ nlmclnt_release_lockargs(req);
+ if (status < 0)
+ return status;
+
+ status = req->a_res.status;
+ if (status == NLM_LCK_GRANTED) {
+ fl->fl_type = F_UNLCK;
+ } if (status == NLM_LCK_DENIED) {
+ /*
+ * Report the conflicting lock back to the application.
+ */
+ locks_copy_lock(fl, &req->a_res.lock.fl);
+ fl->fl_pid = 0;
+ } else {
+ return nlm_stat_to_errno(req->a_res.status);
+ }
+
+ return 0;
+}
+
+static void nlmclnt_locks_copy_lock(struct file_lock *new, struct file_lock *fl)
+{
+ memcpy(&new->fl_u.nfs_fl, &fl->fl_u.nfs_fl, sizeof(new->fl_u.nfs_fl));
+ nlm_get_lockowner(new->fl_u.nfs_fl.owner);
+}
+
+static void nlmclnt_locks_release_private(struct file_lock *fl)
+{
+ nlm_put_lockowner(fl->fl_u.nfs_fl.owner);
+ fl->fl_ops = NULL;
+}
+
+static struct file_lock_operations nlmclnt_lock_ops = {
+ .fl_copy_lock = nlmclnt_locks_copy_lock,
+ .fl_release_private = nlmclnt_locks_release_private,
+};
+
+static void nlmclnt_locks_init_private(struct file_lock *fl, struct nlm_host *host)
+{
+ BUG_ON(fl->fl_ops != NULL);
+ fl->fl_u.nfs_fl.state = 0;
+ fl->fl_u.nfs_fl.flags = 0;
+ fl->fl_u.nfs_fl.owner = nlm_find_lockowner(host, fl->fl_owner);
+ fl->fl_ops = &nlmclnt_lock_ops;
+}
+
+static void do_vfs_lock(struct file_lock *fl)
+{
+ int res = 0;
+ switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) {
+ case FL_POSIX:
+ res = posix_lock_file_wait(fl->fl_file, fl);
+ break;
+ case FL_FLOCK:
+ res = flock_lock_file_wait(fl->fl_file, fl);
+ break;
+ default:
+ BUG();
+ }
+ if (res < 0)
+ printk(KERN_WARNING "%s: VFS is out of sync with lock manager!\n",
+ __FUNCTION__);
+}
+
+/*
+ * LOCK: Try to create a lock
+ *
+ * Programmer Harassment Alert
+ *
+ * When given a blocking lock request in a sync RPC call, the HPUX lockd
+ * will faithfully return LCK_BLOCKED but never cares to notify us when
+ * the lock could be granted. This way, our local process could hang
+ * around forever waiting for the callback.
+ *
+ * Solution A: Implement busy-waiting
+ * Solution B: Use the async version of the call (NLM_LOCK_{MSG,RES})
+ *
+ * For now I am implementing solution A, because I hate the idea of
+ * re-implementing lockd for a third time in two months. The async
+ * calls shouldn't be too hard to do, however.
+ *
+ * This is one of the lovely things about standards in the NFS area:
+ * they're so soft and squishy you can't really blame HP for doing this.
+ */
+static int
+nlmclnt_lock(struct nlm_rqst *req, struct file_lock *fl)
+{
+ struct nlm_host *host = req->a_host;
+ struct nlm_res *resp = &req->a_res;
+ int status;
+
+ if (!host->h_monitored && nsm_monitor(host) < 0) {
+ printk(KERN_NOTICE "lockd: failed to monitor %s\n",
+ host->h_name);
+ status = -ENOLCK;
+ goto out;
+ }
+
+ do {
+ if ((status = nlmclnt_call(req, NLMPROC_LOCK)) >= 0) {
+ if (resp->status != NLM_LCK_BLOCKED)
+ break;
+ status = nlmclnt_block(host, fl, &resp->status);
+ }
+ if (status < 0)
+ goto out;
+ } while (resp->status == NLM_LCK_BLOCKED && req->a_args.block);
+
+ if (resp->status == NLM_LCK_GRANTED) {
+ fl->fl_u.nfs_fl.state = host->h_state;
+ fl->fl_u.nfs_fl.flags |= NFS_LCK_GRANTED;
+ fl->fl_flags |= FL_SLEEP;
+ do_vfs_lock(fl);
+ }
+ status = nlm_stat_to_errno(resp->status);
+out:
+ nlmclnt_release_lockargs(req);
+ return status;
+}
+
+/*
+ * RECLAIM: Try to reclaim a lock
+ */
+int
+nlmclnt_reclaim(struct nlm_host *host, struct file_lock *fl)
+{
+ struct nlm_rqst reqst, *req;
+ int status;
+
+ req = &reqst;
+ memset(req, 0, sizeof(*req));
+ locks_init_lock(&req->a_args.lock.fl);
+ locks_init_lock(&req->a_res.lock.fl);
+ req->a_host = host;
+ req->a_flags = 0;
+
+ /* Set up the argument struct */
+ nlmclnt_setlockargs(req, fl);
+ req->a_args.reclaim = 1;
+
+ if ((status = nlmclnt_call(req, NLMPROC_LOCK)) >= 0
+ && req->a_res.status == NLM_LCK_GRANTED)
+ return 0;
+
+ printk(KERN_WARNING "lockd: failed to reclaim lock for pid %d "
+ "(errno %d, status %d)\n", fl->fl_pid,
+ status, req->a_res.status);
+
+ /*
+ * FIXME: This is a serious failure. We can
+ *
+ * a. Ignore the problem
+ * b. Send the owning process some signal (Linux doesn't have
+ * SIGLOST, though...)
+ * c. Retry the operation
+ *
+ * Until someone comes up with a simple implementation
+ * for b or c, I'll choose option a.
+ */
+
+ return -ENOLCK;
+}
+
+/*
+ * UNLOCK: remove an existing lock
+ */
+static int
+nlmclnt_unlock(struct nlm_rqst *req, struct file_lock *fl)
+{
+ struct nlm_res *resp = &req->a_res;
+ int status;
+
+ /* Clean the GRANTED flag now so the lock doesn't get
+ * reclaimed while we're stuck in the unlock call. */
+ fl->fl_u.nfs_fl.flags &= ~NFS_LCK_GRANTED;
+
+ if (req->a_flags & RPC_TASK_ASYNC) {
+ status = nlmclnt_async_call(req, NLMPROC_UNLOCK,
+ nlmclnt_unlock_callback);
+ /* Hrmf... Do the unlock early since locks_remove_posix()
+ * really expects us to free the lock synchronously */
+ do_vfs_lock(fl);
+ if (status < 0) {
+ nlmclnt_release_lockargs(req);
+ kfree(req);
+ }
+ return status;
+ }
+
+ status = nlmclnt_call(req, NLMPROC_UNLOCK);
+ nlmclnt_release_lockargs(req);
+ if (status < 0)
+ return status;
+
+ do_vfs_lock(fl);
+ if (resp->status == NLM_LCK_GRANTED)
+ return 0;
+
+ if (resp->status != NLM_LCK_DENIED_NOLOCKS)
+ printk("lockd: unexpected unlock status: %d\n", resp->status);
+
+ /* What to do now? I'm out of my depth... */
+
+ return -ENOLCK;
+}
+
+static void
+nlmclnt_unlock_callback(struct rpc_task *task)
+{
+ struct nlm_rqst *req = (struct nlm_rqst *) task->tk_calldata;
+ int status = req->a_res.status;
+
+ if (RPC_ASSASSINATED(task))
+ goto die;
+
+ if (task->tk_status < 0) {
+ dprintk("lockd: unlock failed (err = %d)\n", -task->tk_status);
+ goto retry_rebind;
+ }
+ if (status == NLM_LCK_DENIED_GRACE_PERIOD) {
+ rpc_delay(task, NLMCLNT_GRACE_WAIT);
+ goto retry_unlock;
+ }
+ if (status != NLM_LCK_GRANTED)
+ printk(KERN_WARNING "lockd: unexpected unlock status: %d\n", status);
+die:
+ nlm_release_host(req->a_host);
+ nlmclnt_release_lockargs(req);
+ kfree(req);
+ return;
+ retry_rebind:
+ nlm_rebind_host(req->a_host);
+ retry_unlock:
+ rpc_restart_call(task);
+}
+
+/*
+ * Cancel a blocked lock request.
+ * We always use an async RPC call for this in order not to hang a
+ * process that has been Ctrl-C'ed.
+ */
+int
+nlmclnt_cancel(struct nlm_host *host, struct file_lock *fl)
+{
+ struct nlm_rqst *req;
+ unsigned long flags;
+ sigset_t oldset;
+ int status;
+
+ /* Block all signals while setting up call */
+ spin_lock_irqsave(¤t->sighand->siglock, flags);
+ oldset = current->blocked;
+ sigfillset(¤t->blocked);
+ recalc_sigpending();
+ spin_unlock_irqrestore(¤t->sighand->siglock, flags);
+
+ req = nlmclnt_alloc_call();
+ if (!req)
+ return -ENOMEM;
+ req->a_host = host;
+ req->a_flags = RPC_TASK_ASYNC;
+
+ nlmclnt_setlockargs(req, fl);
+
+ status = nlmclnt_async_call(req, NLMPROC_CANCEL,
+ nlmclnt_cancel_callback);
+ if (status < 0) {
+ nlmclnt_release_lockargs(req);
+ kfree(req);
+ }
+
+ spin_lock_irqsave(¤t->sighand->siglock, flags);
+ current->blocked = oldset;
+ recalc_sigpending();
+ spin_unlock_irqrestore(¤t->sighand->siglock, flags);
+
+ return status;
+}
+
+static void
+nlmclnt_cancel_callback(struct rpc_task *task)
+{
+ struct nlm_rqst *req = (struct nlm_rqst *) task->tk_calldata;
+
+ if (RPC_ASSASSINATED(task))
+ goto die;
+
+ if (task->tk_status < 0) {
+ dprintk("lockd: CANCEL call error %d, retrying.\n",
+ task->tk_status);
+ goto retry_cancel;
+ }
+
+ dprintk("lockd: cancel status %d (task %d)\n",
+ req->a_res.status, task->tk_pid);
+
+ switch (req->a_res.status) {
+ case NLM_LCK_GRANTED:
+ case NLM_LCK_DENIED_GRACE_PERIOD:
+ /* Everything's good */
+ break;
+ case NLM_LCK_DENIED_NOLOCKS:
+ dprintk("lockd: CANCEL failed (server has no locks)\n");
+ goto retry_cancel;
+ default:
+ printk(KERN_NOTICE "lockd: weird return %d for CANCEL call\n",
+ req->a_res.status);
+ }
+
+die:
+ nlm_release_host(req->a_host);
+ nlmclnt_release_lockargs(req);
+ kfree(req);
+ return;
+
+retry_cancel:
+ nlm_rebind_host(req->a_host);
+ rpc_restart_call(task);
+ rpc_delay(task, 30 * HZ);
+}
+
+/*
+ * Convert an NLM status code to a generic kernel errno
+ */
+static int
+nlm_stat_to_errno(u32 status)
+{
+ switch(status) {
+ case NLM_LCK_GRANTED:
+ return 0;
+ case NLM_LCK_DENIED:
+ return -EAGAIN;
+ case NLM_LCK_DENIED_NOLOCKS:
+ case NLM_LCK_DENIED_GRACE_PERIOD:
+ return -ENOLCK;
+ case NLM_LCK_BLOCKED:
+ printk(KERN_NOTICE "lockd: unexpected status NLM_BLOCKED\n");
+ return -ENOLCK;
+#ifdef CONFIG_LOCKD_V4
+ case NLM_DEADLCK:
+ return -EDEADLK;
+ case NLM_ROFS:
+ return -EROFS;
+ case NLM_STALE_FH:
+ return -ESTALE;
+ case NLM_FBIG:
+ return -EOVERFLOW;
+ case NLM_FAILED:
+ return -ENOLCK;
+#endif
+ }
+ printk(KERN_NOTICE "lockd: unexpected server status %d\n", status);
+ return -ENOLCK;
+}
