diff options
Diffstat (limited to 'source4/ntvfs/sysdep/sys_lease_linux.c')
| -rw-r--r-- | source4/ntvfs/sysdep/sys_lease_linux.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/source4/ntvfs/sysdep/sys_lease_linux.c b/source4/ntvfs/sysdep/sys_lease_linux.c new file mode 100644 index 0000000..54c0007 --- /dev/null +++ b/source4/ntvfs/sysdep/sys_lease_linux.c @@ -0,0 +1,215 @@ +/* + Unix SMB/CIFS implementation. + + Copyright (C) Stefan Metzmacher 2008 + + 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 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +/* + lease (oplock) implementation using fcntl F_SETLEASE on linux +*/ + +#include "includes.h" +#include <tevent.h> +#include "system/filesys.h" +#include "ntvfs/sysdep/sys_lease.h" +#include "ntvfs/ntvfs.h" +#include "librpc/gen_ndr/ndr_opendb.h" +#include "../lib/util/dlinklist.h" +#include "cluster/cluster.h" + +NTSTATUS sys_lease_linux_init(TALLOC_CTX *); + +#define LINUX_LEASE_RT_SIGNAL (SIGRTMIN+1) + +struct linux_lease_pending { + struct linux_lease_pending *prev, *next; + struct sys_lease_context *ctx; + struct opendb_entry e; +}; + +/* the global linked list of pending leases */ +static struct linux_lease_pending *leases; + +static void linux_lease_signal_handler(struct tevent_context *ev_ctx, + struct tevent_signal *se, + int signum, int count, + void *_info, void *private_data) +{ + struct sys_lease_context *ctx = talloc_get_type(private_data, + struct sys_lease_context); + siginfo_t *info = (siginfo_t *)_info; + struct linux_lease_pending *c; + int got_fd = info->si_fd; + + for (c = leases; c; c = c->next) { + int *fd = (int *)c->e.fd; + + if (got_fd == *fd) { + break; + } + } + + if (!c) { + return; + } + + ctx->break_send(ctx->msg_ctx, &c->e, OPLOCK_BREAK_TO_NONE); +} + +static int linux_lease_pending_destructor(struct linux_lease_pending *p) +{ + int ret; + int *fd = (int *)p->e.fd; + + DLIST_REMOVE(leases, p); + + if (*fd == -1) { + return 0; + } + + ret = fcntl(*fd, F_SETLEASE, F_UNLCK); + if (ret == -1) { + DEBUG(0,("%s: failed to remove oplock: %s\n", + __FUNCTION__, strerror(errno))); + } + + return 0; +} + +static NTSTATUS linux_lease_init(struct sys_lease_context *ctx) +{ + struct tevent_signal *se; + + se = tevent_add_signal(ctx->event_ctx, ctx, + LINUX_LEASE_RT_SIGNAL, SA_SIGINFO, + linux_lease_signal_handler, ctx); + NT_STATUS_HAVE_NO_MEMORY(se); + + return NT_STATUS_OK; +} + +static NTSTATUS linux_lease_setup(struct sys_lease_context *ctx, + struct opendb_entry *e) +{ + int ret; + int *fd = (int *)e->fd; + struct linux_lease_pending *p; + + if (e->oplock_level == OPLOCK_NONE) { + e->fd = NULL; + return NT_STATUS_OK; + } else if (e->oplock_level == OPLOCK_LEVEL_II) { + /* + * the linux kernel doesn't support level2 oplocks + * so fix up the granted oplock level + */ + e->oplock_level = OPLOCK_NONE; + e->allow_level_II_oplock = false; + e->fd = NULL; + return NT_STATUS_OK; + } + + p = talloc(ctx, struct linux_lease_pending); + NT_STATUS_HAVE_NO_MEMORY(p); + + p->ctx = ctx; + p->e = *e; + + ret = fcntl(*fd, F_SETSIG, LINUX_LEASE_RT_SIGNAL); + if (ret == -1) { + talloc_free(p); + return map_nt_error_from_unix_common(errno); + } + + ret = fcntl(*fd, F_SETLEASE, F_WRLCK); + if (ret == -1) { + talloc_free(p); + return map_nt_error_from_unix_common(errno); + } + + DLIST_ADD(leases, p); + + talloc_set_destructor(p, linux_lease_pending_destructor); + + return NT_STATUS_OK; +} + +static NTSTATUS linux_lease_remove(struct sys_lease_context *ctx, + struct opendb_entry *e); + +static NTSTATUS linux_lease_update(struct sys_lease_context *ctx, + struct opendb_entry *e) +{ + struct linux_lease_pending *c; + + for (c = leases; c; c = c->next) { + if (c->e.fd == e->fd) { + break; + } + } + + if (!c) { + return NT_STATUS_OBJECT_NAME_NOT_FOUND; + } + + /* + * set the fd pointer to NULL so that the caller + * will not call the remove function as the oplock + * is already removed + */ + e->fd = NULL; + + talloc_free(c); + + return NT_STATUS_OK; +} + +static NTSTATUS linux_lease_remove(struct sys_lease_context *ctx, + struct opendb_entry *e) +{ + struct linux_lease_pending *c; + + for (c = leases; c; c = c->next) { + if (c->e.fd == e->fd) { + break; + } + } + + if (!c) { + return NT_STATUS_OBJECT_NAME_NOT_FOUND; + } + + talloc_free(c); + + return NT_STATUS_OK; +} + +static struct sys_lease_ops linux_lease_ops = { + .name = "linux", + .init = linux_lease_init, + .setup = linux_lease_setup, + .update = linux_lease_update, + .remove = linux_lease_remove +}; + +/* + initialise the linux lease module + */ +NTSTATUS sys_lease_linux_init(TALLOC_CTX *ctx) +{ + /* register ourselves as a system lease module */ + return sys_lease_register(ctx, &linux_lease_ops); +} |