diff options
Diffstat (limited to 'source4/cluster/ctdb/brlock_ctdb.c')
| -rw-r--r-- | source4/cluster/ctdb/brlock_ctdb.c | 945 |
1 files changed, 945 insertions, 0 deletions
diff --git a/source4/cluster/ctdb/brlock_ctdb.c b/source4/cluster/ctdb/brlock_ctdb.c new file mode 100644 index 0000000000..1b22c6c727 --- /dev/null +++ b/source4/cluster/ctdb/brlock_ctdb.c @@ -0,0 +1,945 @@ +/* + Unix SMB/CIFS implementation. + + generic byte range locking code - ctdb backend + + Copyright (C) Andrew Tridgell 2006 + + 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/>. +*/ + +#include "includes.h" +#include "system/filesys.h" +#include "lib/tdb/include/tdb.h" +#include "messaging/messaging.h" +#include "lib/messaging/irpc.h" +#include "libcli/libcli.h" +#include "cluster/cluster.h" +#include "ntvfs/ntvfs.h" +#include "ntvfs/common/brlock.h" +#include "include/ctdb.h" + +enum my_functions {FUNC_BRL_LOCK=1, FUNC_BRL_UNLOCK=2, + FUNC_BRL_REMOVE_PENDING=3, FUNC_BRL_LOCKTEST=4, + FUNC_BRL_CLOSE=5}; + +/* + in this module a "DATA_BLOB *file_key" is a blob that uniquely identifies + a file. For a local posix filesystem this will usually be a combination + of the device and inode numbers of the file, but it can be anything + that uniquely idetifies a file for locking purposes, as long + as it is applied consistently. +*/ + +/* this struct is typically attached to tcon */ +struct brl_context { + struct ctdb_context *ctdb; + struct ctdb_db_context *ctdb_db; + struct server_id server; + struct messaging_context *messaging_ctx; +}; + +/* + the lock context contains the elements that define whether one + lock is the same as another lock +*/ +struct lock_context { + struct server_id server; + uint16_t smbpid; + struct brl_context *ctx; +}; + +/* The data in brlock records is an unsorted linear array of these + records. It is unnecessary to store the count as tdb provides the + size of the record */ +struct lock_struct { + struct lock_context context; + struct ntvfs_handle *ntvfs; + uint64_t start; + uint64_t size; + enum brl_type lock_type; + void *notify_ptr; +}; + +/* this struct is attached to on open file handle */ +struct brl_handle { + DATA_BLOB key; + struct ntvfs_handle *ntvfs; + struct lock_struct last_lock; +}; + +#if 0 +static void show_locks(const char *op, struct lock_struct *locks, int count) +{ + int i; + DEBUG(0,("OP: %s\n", op)); + if (locks == NULL) return; + for (i=0;i<count;i++) { + DEBUG(0,("%2d: %4d %4d %d.%d.%d %p %p\n", + i, (int)locks[i].start, (int)locks[i].size, + locks[i].context.server.node, + locks[i].context.server.id, + locks[i].context.smbpid, + locks[i].context.ctx, + locks[i].ntvfs)); + } +} +#endif + +/* + Open up the brlock.tdb database. Close it down using + talloc_free(). We need the messaging_ctx to allow for + pending lock notifications. +*/ +static struct brl_context *brl_ctdb_init(TALLOC_CTX *mem_ctx, struct server_id server, struct loadparm_context *lp_ctx, + struct messaging_context *messaging_ctx) +{ + struct ctdb_context *ctdb = talloc_get_type(cluster_backend_handle(), + struct ctdb_context); + struct brl_context *brl; + + brl = talloc(mem_ctx, struct brl_context); + if (brl == NULL) { + return NULL; + } + + brl->ctdb = ctdb; + brl->ctdb_db = ctdb_db_handle(ctdb, "brlock"); + if (brl->ctdb_db == NULL) { + DEBUG(0,("Failed to get attached ctdb db handle for brlock\n")); + talloc_free(brl); + return NULL; + } + brl->server = server; + brl->messaging_ctx = messaging_ctx; + + return brl; +} + +static struct brl_handle *brl_ctdb_create_handle(TALLOC_CTX *mem_ctx, struct ntvfs_handle *ntvfs, + DATA_BLOB *file_key) +{ + struct brl_handle *brlh; + + brlh = talloc(mem_ctx, struct brl_handle); + if (brlh == NULL) { + return NULL; + } + + brlh->key = *file_key; + brlh->ntvfs = ntvfs; + ZERO_STRUCT(brlh->last_lock); + + return brlh; +} + +/* + see if two locking contexts are equal +*/ +static bool brl_ctdb_same_context(struct lock_context *ctx1, struct lock_context *ctx2) +{ + return (cluster_id_equal(&ctx1->server, &ctx2->server) && + ctx1->smbpid == ctx2->smbpid && + ctx1->ctx == ctx2->ctx); +} + +/* + see if lck1 and lck2 overlap +*/ +static bool brl_ctdb_overlap(struct lock_struct *lck1, + struct lock_struct *lck2) +{ + /* this extra check is not redundent - it copes with locks + that go beyond the end of 64 bit file space */ + if (lck1->size != 0 && + lck1->start == lck2->start && + lck1->size == lck2->size) { + return true; + } + + if (lck1->start >= (lck2->start+lck2->size) || + lck2->start >= (lck1->start+lck1->size)) { + return false; + } + return true; +} + +/* + See if lock2 can be added when lock1 is in place. +*/ +static bool brl_ctdb_conflict(struct lock_struct *lck1, + struct lock_struct *lck2) +{ + /* pending locks don't conflict with anything */ + if (lck1->lock_type >= PENDING_READ_LOCK || + lck2->lock_type >= PENDING_READ_LOCK) { + return false; + } + + if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) { + return false; + } + + if (brl_ctdb_same_context(&lck1->context, &lck2->context) && + lck2->lock_type == READ_LOCK && lck1->ntvfs == lck2->ntvfs) { + return false; + } + + return brl_ctdb_overlap(lck1, lck2); +} + + +/* + Check to see if this lock conflicts, but ignore our own locks on the + same fnum only. +*/ +static bool brl_ctdb_conflict_other(struct lock_struct *lck1, struct lock_struct *lck2) +{ + /* pending locks don't conflict with anything */ + if (lck1->lock_type >= PENDING_READ_LOCK || + lck2->lock_type >= PENDING_READ_LOCK) { + return false; + } + + if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) + return false; + + /* + * note that incoming write calls conflict with existing READ + * locks even if the context is the same. JRA. See LOCKTEST7 + * in smbtorture. + */ + if (brl_ctdb_same_context(&lck1->context, &lck2->context) && + lck1->ntvfs == lck2->ntvfs && + (lck2->lock_type == READ_LOCK || lck1->lock_type == WRITE_LOCK)) { + return false; + } + + return brl_ctdb_overlap(lck1, lck2); +} + + +/* + amazingly enough, w2k3 "remembers" whether the last lock failure + is the same as this one and changes its error code. I wonder if any + app depends on this? +*/ +static NTSTATUS brl_ctdb_lock_failed(struct brl_handle *brlh, struct lock_struct *lock) +{ + /* + * this function is only called for non pending lock! + */ + + /* in SMB2 mode always return NT_STATUS_LOCK_NOT_GRANTED! */ + if (lock->ntvfs->ctx->protocol == PROTOCOL_SMB2) { + return NT_STATUS_LOCK_NOT_GRANTED; + } + + /* + * if the notify_ptr is non NULL, + * it means that we're at the end of a pending lock + * and the real lock is requested after the timeout went by + * In this case we need to remember the last_lock and always + * give FILE_LOCK_CONFLICT + */ + if (lock->notify_ptr) { + brlh->last_lock = *lock; + return NT_STATUS_FILE_LOCK_CONFLICT; + } + + /* + * amazing the little things you learn with a test + * suite. Locks beyond this offset (as a 64 bit + * number!) always generate the conflict error code, + * unless the top bit is set + */ + if (lock->start >= 0xEF000000 && (lock->start >> 63) == 0) { + brlh->last_lock = *lock; + return NT_STATUS_FILE_LOCK_CONFLICT; + } + + /* + * if the current lock matches the last failed lock on the file handle + * and starts at the same offset, then FILE_LOCK_CONFLICT should be returned + */ + if (cluster_id_equal(&lock->context.server, &brlh->last_lock.context.server) && + lock->context.ctx == brlh->last_lock.context.ctx && + lock->ntvfs == brlh->last_lock.ntvfs && + lock->start == brlh->last_lock.start) { + return NT_STATUS_FILE_LOCK_CONFLICT; + } + + brlh->last_lock = *lock; + return NT_STATUS_LOCK_NOT_GRANTED; +} + +struct ctdb_lock_req { + uint16_t smbpid; + uint64_t start; + uint64_t size; + enum brl_type lock_type; + void *notify_ptr; + struct server_id server; + struct brl_context *brl; + struct ntvfs_handle *ntvfs; +}; + +/* + ctdb call handling brl_lock() +*/ +static int brl_ctdb_lock_func(struct ctdb_call_info *call) +{ + struct ctdb_lock_req *req = (struct ctdb_lock_req *)call->call_data->dptr; + TDB_DATA dbuf; + int count=0, i; + struct lock_struct lock, *locks=NULL; + NTSTATUS status = NT_STATUS_OK; + + /* if this is a pending lock, then with the chainlock held we + try to get the real lock. If we succeed then we don't need + to make it pending. This prevents a possible race condition + where the pending lock gets created after the lock that is + preventing the real lock gets removed */ + if (req->lock_type >= PENDING_READ_LOCK) { + enum brl_type lock_type = req->lock_type; + req->lock_type = (req->lock_type==PENDING_READ_LOCK? READ_LOCK : WRITE_LOCK); + if (brl_ctdb_lock_func(call) == 0 && call->status == NT_STATUS_V(NT_STATUS_OK)) { + return 0; + } + req->lock_type = lock_type; + } + + dbuf = call->record_data; + + ZERO_STRUCT(lock); + lock.context.smbpid = req->smbpid; + lock.context.server = req->server; + lock.context.ctx = req->brl; + lock.ntvfs = req->ntvfs; + lock.start = req->start; + lock.size = req->size; + lock.lock_type = req->lock_type; + lock.notify_ptr = req->notify_ptr; + + if (dbuf.dptr) { + /* there are existing locks - make sure they don't conflict */ + locks = (struct lock_struct *)dbuf.dptr; + count = dbuf.dsize / sizeof(*locks); + + for (i=0; i<count; i++) { + if (brl_ctdb_conflict(&locks[i], &lock)) { + status = NT_STATUS_LOCK_NOT_GRANTED; + goto reply; + } + } + } + + call->new_data = talloc(call, TDB_DATA); + if (call->new_data == NULL) { + return CTDB_ERR_NOMEM; + } + + call->new_data->dptr = talloc_size(call, dbuf.dsize + sizeof(lock)); + if (call->new_data->dptr == NULL) { + return CTDB_ERR_NOMEM; + } + memcpy(call->new_data->dptr, locks, dbuf.dsize); + memcpy(call->new_data->dptr+dbuf.dsize, &lock, sizeof(lock)); + call->new_data->dsize = dbuf.dsize + sizeof(lock); + + if (req->lock_type >= PENDING_READ_LOCK) { + status = NT_STATUS_LOCK_NOT_GRANTED; + } + +reply: + call->status = NT_STATUS_V(status); + + return 0; +} + + +/* + Lock a range of bytes. The lock_type can be a PENDING_*_LOCK, in + which case a real lock is first tried, and if that fails then a + pending lock is created. When the pending lock is triggered (by + someone else closing an overlapping lock range) a messaging + notification is sent, identified by the notify_ptr +*/ +static NTSTATUS brl_ctdb_lock(struct brl_context *brl, + struct brl_handle *brlh, + uint16_t smbpid, + uint64_t start, uint64_t size, + enum brl_type lock_type, + void *notify_ptr) +{ + struct ctdb_lock_req req; + struct ctdb_call call; + int ret; + NTSTATUS status; + + call.call_id = FUNC_BRL_LOCK; + call.key.dptr = brlh->key.data; + call.key.dsize = brlh->key.length; + call.call_data.dptr = (uint8_t *)&req; + call.call_data.dsize = sizeof(req); + call.flags = 0; + call.status = 0; + + ZERO_STRUCT(req); + req.smbpid = smbpid; + req.start = start; + req.size = size; + req.lock_type = lock_type; + req.notify_ptr = notify_ptr; + req.server = brl->server; + req.brl = brl; + req.ntvfs = brlh->ntvfs; + + ret = ctdb_call(brl->ctdb_db, &call); + if (ret == -1) { + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + status = NT_STATUS(call.status); + + if (NT_STATUS_EQUAL(status, NT_STATUS_LOCK_NOT_GRANTED)) { + struct lock_struct lock; + lock.context.smbpid = smbpid; + lock.context.server = brl->server; + lock.context.ctx = brl; + lock.ntvfs = brlh->ntvfs; + lock.start = start; + lock.size = size; + lock.lock_type = lock_type; + lock.notify_ptr = notify_ptr; + status = brl_ctdb_lock_failed(brlh, &lock); + } + + return status; +} + +/* + we are removing a lock that might be holding up a pending lock. Scan + for pending locks that cover this range and if we find any then + notify the server that it should retry the lock. In this backend, we + notify by sending the list of locks that need to be notified on back + in the reply_data of the ctdb call. The caller then does the + messaging for us. +*/ +static int brl_ctdb_notify_unlock(struct ctdb_call_info *call, + struct lock_struct *locks, int count, + struct lock_struct *removed_lock) +{ + int i, last_notice; + + /* the last_notice logic is to prevent stampeding on a lock + range. It prevents us sending hundreds of notifies on the + same range of bytes. It doesn't prevent all possible + stampedes, but it does prevent the most common problem */ + last_notice = -1; + + for (i=0;i<count;i++) { + if (locks[i].lock_type >= PENDING_READ_LOCK && + brl_ctdb_overlap(&locks[i], removed_lock)) { + struct lock_struct *nlocks; + int ncount; + + if (last_notice != -1 && brl_ctdb_overlap(&locks[i], &locks[last_notice])) { + continue; + } + if (locks[i].lock_type == PENDING_WRITE_LOCK) { + last_notice = i; + } + if (call->reply_data == NULL) { + call->reply_data = talloc_zero(call, TDB_DATA); + if (call->reply_data == NULL) { + return CTDB_ERR_NOMEM; + } + } + /* add to the list of pending locks to notify caller of */ + ncount = call->reply_data->dsize / sizeof(struct lock_struct); + nlocks = talloc_realloc(call->reply_data, call->reply_data->dptr, + struct lock_struct, ncount + 1); + if (nlocks == NULL) { + return CTDB_ERR_NOMEM; + } + call->reply_data->dptr = (uint8_t *)nlocks; + nlocks[ncount] = locks[i]; + call->reply_data->dsize += sizeof(struct lock_struct); + } + } + + return 0; +} + +/* + send notifications for all pending locks - the file is being closed by this + user +*/ +static int brl_ctdb_notify_all(struct ctdb_call_info *call, + struct lock_struct *locks, int count) +{ + int i; + for (i=0;i<count;i++) { + if (locks->lock_type >= PENDING_READ_LOCK) { + int ret = brl_ctdb_notify_unlock(call, locks, count, &locks[i]); + if (ret != 0) return ret; + } + } + return 0; +} + +/* + send off any messages needed to notify of pending locks that should now retry +*/ +static void brl_ctdb_notify_send(struct brl_context *brl, TDB_DATA *reply_data) +{ + struct lock_struct *locks = (struct lock_struct *)reply_data->dptr; + int i, count = reply_data->dsize / sizeof(struct lock_struct); + for (i=0;i<count;i++) { + messaging_send_ptr(brl->messaging_ctx, locks[i].context.server, + MSG_BRL_RETRY, locks[i].notify_ptr); + } +} + + +struct ctdb_unlock_req { + uint16_t smbpid; + uint64_t start; + uint64_t size; + struct server_id server; + struct brl_context *brl; + struct ntvfs_handle *ntvfs; +}; + +/* + Unlock a range of bytes. +*/ +static int brl_ctdb_unlock_func(struct ctdb_call_info *call) +{ + struct ctdb_unlock_req *req = (struct ctdb_unlock_req *)call->call_data->dptr; + TDB_DATA dbuf; + int count, i; + struct lock_struct *locks, *lock; + struct lock_context context; + NTSTATUS status = NT_STATUS_OK; + + dbuf = call->record_data; + + context.smbpid = req->smbpid; + context.server = req->server; + context.ctx = req->brl; + + /* there are existing locks - find a match */ + locks = (struct lock_struct *)dbuf.dptr; + count = dbuf.dsize / sizeof(*locks); + + for (i=0; i<count; i++) { + lock = &locks[i]; + if (brl_ctdb_same_context(&lock->context, &context) && + lock->ntvfs == req->ntvfs && + lock->start == req->start && + lock->size == req->size && + lock->lock_type == WRITE_LOCK) { + break; + } + } + if (i < count) goto found; + + for (i=0; i<count; i++) { + lock = &locks[i]; + if (brl_ctdb_same_context(&lock->context, &context) && + lock->ntvfs == req->ntvfs && + lock->start == req->start && + lock->size == req->size && + lock->lock_type < PENDING_READ_LOCK) { + break; + } + } + +found: + if (i < count) { + struct lock_struct removed_lock = *lock; + + call->new_data = talloc(call, TDB_DATA); + if (call->new_data == NULL) { + return CTDB_ERR_NOMEM; + } + + call->new_data->dptr = talloc_size(call, dbuf.dsize - sizeof(*lock)); + if (call->new_data->dptr == NULL) { + return CTDB_ERR_NOMEM; + } + call->new_data->dsize = dbuf.dsize - sizeof(*lock); + + memcpy(call->new_data->dptr, locks, i*sizeof(*lock)); + memcpy(call->new_data->dptr+i*sizeof(*lock), locks+i+1, + (count-(i+1))*sizeof(*lock)); + + if (count > 1) { + int ret = brl_ctdb_notify_unlock(call, locks, count, &removed_lock); + if (ret != 0) return ret; + } + } + + if (i == count) { + /* we didn't find it */ + status = NT_STATUS_RANGE_NOT_LOCKED; + } + + call->status = NT_STATUS_V(status); + + return 0; +} + + +/* + Unlock a range of bytes. +*/ +static NTSTATUS brl_ctdb_unlock(struct brl_context *brl, + struct brl_handle *brlh, + uint16_t smbpid, + uint64_t start, uint64_t size) +{ + struct ctdb_call call; + struct ctdb_unlock_req req; + int ret; + + call.call_id = FUNC_BRL_UNLOCK; + call.key.dptr = brlh->key.data; + call.key.dsize = brlh->key.length; + call.call_data.dptr = (uint8_t *)&req; + call.call_data.dsize = sizeof(req); + + ZERO_STRUCT(req); + req.smbpid = smbpid; + req.start = start; + req.size = size; + req.server = brl->server; + req.brl = brl; + req.ntvfs = brlh->ntvfs; + + ret = ctdb_call(brl->ctdb_db, &call); + if (ret == -1) { + DEBUG(0,("ctdb_call failed - %s\n", __location__)); + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + brl_ctdb_notify_send(brl, &call.reply_data); + + return NT_STATUS(call.status); +} + + +struct ctdb_remove_pending_req { + struct server_id server; + void *notify_ptr; +}; + +/* + remove a pending lock. This is called when the caller has either + given up trying to establish a lock or when they have succeeded in + getting it. In either case they no longer need to be notified. +*/ +static int brl_ctdb_remove_pending_func(struct ctdb_call_info *call) +{ + struct ctdb_remove_pending_req *req = (struct ctdb_remove_pending_req *)call->call_data->dptr; + TDB_DATA dbuf; + int count, i; + struct lock_struct *locks; + NTSTATUS status = NT_STATUS_OK; + + dbuf = call->record_data; + + /* there are existing locks - find a match */ + locks = (struct lock_struct *)dbuf.dptr; + count = dbuf.dsize / sizeof(*locks); + + for (i=0; i<count; i++) { + struct lock_struct *lock = &locks[i]; + + if (lock->lock_type >= PENDING_READ_LOCK && + lock->notify_ptr == req->notify_ptr && + cluster_id_equal(&lock->context.server, &req->server)) { + call->new_data = talloc(call, TDB_DATA); + if (call->new_data == NULL) { + return CTDB_ERR_NOMEM; + } + + call->new_data->dptr = talloc_size(call, dbuf.dsize - sizeof(*lock)); + if (call->new_data->dptr == NULL) { + return CTDB_ERR_NOMEM; + } + call->new_data->dsize = dbuf.dsize - sizeof(*lock); + + memcpy(call->new_data->dptr, locks, i*sizeof(*lock)); + memcpy(call->new_data->dptr+i*sizeof(*lock), locks+i+1, + (count-(i+1))*sizeof(*lock)); + break; + } + } + + if (i == count) { + /* we didn't find it */ + status = NT_STATUS_RANGE_NOT_LOCKED; + } + + call->status = NT_STATUS_V(status); + + return 0; +} + +static NTSTATUS brl_ctdb_remove_pending(struct brl_context *brl, + struct brl_handle *brlh, + void *notify_ptr) +{ + struct ctdb_call call; + struct ctdb_remove_pending_req req; + int ret; + + call.call_id = FUNC_BRL_REMOVE_PENDING; + call.key.dptr = brlh->key.data; + call.key.dsize = brlh->key.length; + call.call_data.dptr = (uint8_t *)&req; + call.call_data.dsize = sizeof(req); + + ZERO_STRUCT(req); + req.notify_ptr = notify_ptr; + req.server = brl->server; + + ret = ctdb_call(brl->ctdb_db, &call); + if (ret == -1) { + DEBUG(0,("ctdb_call failed - %s\n", __location__)); + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + return NT_STATUS(call.status); +} + + +struct ctdb_locktest_req { + uint16_t smbpid; + uint64_t start; + uint64_t size; + enum brl_type lock_type; + struct brl_context *brl; + struct server_id server; + struct ntvfs_handle *ntvfs; +}; + +/* + remove a pending lock. This is called when the caller has either + given up trying to establish a lock or when they have succeeded in + getting it. In either case they no longer need to be notified. +*/ +static int brl_ctdb_locktest_func(struct ctdb_call_info *call) +{ + struct ctdb_locktest_req *req = (struct ctdb_locktest_req *)call->call_data->dptr; + TDB_DATA dbuf; + int count, i; + struct lock_struct *locks, lock; + NTSTATUS status = NT_STATUS_OK; + + lock.context.smbpid = req->smbpid; + lock.context.server = req->server; + lock.context.ctx = req->brl; + lock.ntvfs = req->ntvfs; + lock.start = req->start; + lock.size = req->size; + lock.lock_type = req->lock_type; + + dbuf = call->record_data; + + /* there are existing locks - find a match */ + locks = (struct lock_struct *)dbuf.dptr; + count = dbuf.dsize / sizeof(*locks); + + for (i=0; i<count; i++) { + if (brl_ctdb_conflict_other(&locks[i], &lock)) { + status = NT_STATUS_FILE_LOCK_CONFLICT; + break; + } + } + + call->status = NT_STATUS_V(status); + + return 0; +} + +/* + Test if we are allowed to perform IO on a region of an open file +*/ +static NTSTATUS brl_ctdb_locktest(struct brl_context *brl, + struct brl_handle *brlh, + uint16_t smbpid, + uint64_t start, uint64_t size, + enum brl_type lock_type) +{ + struct ctdb_call call; + struct ctdb_locktest_req req; + int ret; + + call.call_id = FUNC_BRL_LOCKTEST; + call.key.dptr = brlh->key.data; + call.key.dsize = brlh->key.length; + call.call_data.dptr = (uint8_t *)&req; + call.call_data.dsize = sizeof(req); + + ZERO_STRUCT(req); + req.smbpid = smbpid; + req.start = start; + req.size = size; + req.lock_type = lock_type; + req.server = brl->server; + req.brl = brl; + req.ntvfs = brlh->ntvfs; + + ret = ctdb_call(brl->ctdb_db, &call); + if (ret == -1) { + DEBUG(0,("ctdb_call failed - %s\n", __location__)); + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + return NT_STATUS(call.status); +} + + +struct ctdb_close_req { + struct brl_context *brl; + struct server_id server; + struct ntvfs_handle *ntvfs; +}; + +/* + remove a pending lock. This is called when the caller has either + given up trying to establish a lock or when they have succeeded in + getting it. In either case they no longer need to be notified. +*/ +static int brl_ctdb_close_func(struct ctdb_call_info *call) +{ + struct ctdb_close_req *req = (struct ctdb_close_req *)call->call_data->dptr; + TDB_DATA dbuf; + int count, dcount=0, i; + struct lock_struct *locks; + NTSTATUS status = NT_STATUS_OK; + + dbuf = call->record_data; + + /* there are existing locks - find a match */ + locks = (struct lock_struct *)dbuf.dptr; + count = dbuf.dsize / sizeof(*locks); + + for (i=0; i<count; i++) { + struct lock_struct *lock = &locks[i]; + + if (lock->context.ctx == req->brl && + cluster_id_equal(&lock->context.server, &req->server) && + lock->ntvfs == req->ntvfs) { + /* found it - delete it */ + if (count > 1 && i < count-1) { + memmove(&locks[i], &locks[i+1], + sizeof(*locks)*((count-1) - i)); + } + count--; + i--; + dcount++; + } + } + + if (dcount > 0) { + call->new_data = talloc(call, TDB_DATA); + if (call->new_data == NULL) { + return CTDB_ERR_NOMEM; + } + + brl_ctdb_notify_all(call, locks, count); + + call->new_data->dptr = talloc_size(call, count*sizeof(struct lock_struct)); + if (call->new_data->dptr == NULL) { + return CTDB_ERR_NOMEM; + } + call->new_data->dsize = count*sizeof(struct lock_struct); + + memcpy(call->new_data->dptr, locks, count*sizeof(struct lock_struct)); + } + + call->status = NT_STATUS_V(status); + + return 0; +} + +/* + Test if we are allowed to perform IO on a region of an open file +*/ +static NTSTATUS brl_ctdb_close(struct brl_context *brl, + struct brl_handle *brlh) +{ + struct ctdb_call call; + struct ctdb_close_req req; + int ret; + + call.call_id = FUNC_BRL_CLOSE; + call.key.dptr = brlh->key.data; + call.key.dsize = brlh->key.length; + call.call_data.dptr = (uint8_t *)&req; + call.call_data.dsize = sizeof(req); + + ZERO_STRUCT(req); + req.brl = brl; + req.server = brl->server; + req.ntvfs = brlh->ntvfs; + + ret = ctdb_call(brl->ctdb_db, &call); + if (ret == -1) { + DEBUG(0,("ctdb_call failed - %s\n", __location__)); + return NT_STATUS_INTERNAL_DB_CORRUPTION; + } + + brl_ctdb_notify_send(brl, &call.reply_data); + + return NT_STATUS(call.status); +} + + +static const struct brlock_ops brlock_tdb_ops = { + .brl_init = brl_ctdb_init, + .brl_create_handle = brl_ctdb_create_handle, + .brl_lock = brl_ctdb_lock, + .brl_unlock = brl_ctdb_unlock, + .brl_remove_pending = brl_ctdb_remove_pending, + .brl_locktest = brl_ctdb_locktest, + .brl_close = brl_ctdb_close +}; + + +void brl_ctdb_init_ops(void) +{ + struct ctdb_context *ctdb = talloc_get_type(cluster_backend_handle(), + struct ctdb_context); + struct ctdb_db_context *ctdb_db; + + brl_set_ops(&brlock_tdb_ops); + + ctdb_db = ctdb_db_handle(ctdb, "brlock"); + if (ctdb_db == NULL) { + DEBUG(0,("Failed to get attached ctdb db handle for brlock\n")); + return; + } + + ctdb_set_call(ctdb_db, brl_ctdb_lock_func, FUNC_BRL_LOCK); + ctdb_set_call(ctdb_db, brl_ctdb_unlock_func, FUNC_BRL_UNLOCK); + ctdb_set_call(ctdb_db, brl_ctdb_remove_pending_func, FUNC_BRL_REMOVE_PENDING); + ctdb_set_call(ctdb_db, brl_ctdb_locktest_func, FUNC_BRL_LOCKTEST); + ctdb_set_call(ctdb_db, brl_ctdb_close_func, FUNC_BRL_CLOSE); +} |