/*
Unix SMB/CIFS implementation.
byte range locking code
Updated to handle range splits/merges.
Copyright (C) Andrew Tridgell 1992-2000
Copyright (C) Jeremy Allison 1992-2000
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 .
*/
/* This module implements a tdb based byte range locking service,
replacing the fcntl() based byte range locking previously
used. This allows us to provide the same semantics as NT */
#include "includes.h"
#include "system/filesys.h"
#include "locking/proto.h"
#include "smbd/globals.h"
#include "dbwrap.h"
#include "serverid.h"
#include "messages.h"
#undef DBGC_CLASS
#define DBGC_CLASS DBGC_LOCKING
#define ZERO_ZERO 0
/* The open brlock.tdb database. */
static struct db_context *brlock_db;
/****************************************************************************
Debug info at level 10 for lock struct.
****************************************************************************/
static void print_lock_struct(unsigned int i, struct lock_struct *pls)
{
DEBUG(10,("[%u]: smblctx = %llu, tid = %u, pid = %s, ",
i,
(unsigned long long)pls->context.smblctx,
(unsigned int)pls->context.tid,
procid_str(talloc_tos(), &pls->context.pid) ));
DEBUG(10,("start = %.0f, size = %.0f, fnum = %d, %s %s\n",
(double)pls->start,
(double)pls->size,
pls->fnum,
lock_type_name(pls->lock_type),
lock_flav_name(pls->lock_flav) ));
}
/****************************************************************************
See if two locking contexts are equal.
****************************************************************************/
bool brl_same_context(const struct lock_context *ctx1,
const struct lock_context *ctx2)
{
return (procid_equal(&ctx1->pid, &ctx2->pid) &&
(ctx1->smblctx == ctx2->smblctx) &&
(ctx1->tid == ctx2->tid));
}
/****************************************************************************
See if lck1 and lck2 overlap.
****************************************************************************/
static bool brl_overlap(const struct lock_struct *lck1,
const struct lock_struct *lck2)
{
/* XXX Remove for Win7 compatibility. */
/* 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_conflict(const struct lock_struct *lck1,
const struct lock_struct *lck2)
{
/* Ignore PENDING locks. */
if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
return False;
/* Read locks never conflict. */
if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) {
return False;
}
/* A READ lock can stack on top of a WRITE lock if they have the same
* context & fnum. */
if (lck1->lock_type == WRITE_LOCK && lck2->lock_type == READ_LOCK &&
brl_same_context(&lck1->context, &lck2->context) &&
lck1->fnum == lck2->fnum) {
return False;
}
return brl_overlap(lck1, lck2);
}
/****************************************************************************
See if lock2 can be added when lock1 is in place - when both locks are POSIX
flavour. POSIX locks ignore fnum - they only care about dev/ino which we
know already match.
****************************************************************************/
static bool brl_conflict_posix(const struct lock_struct *lck1,
const struct lock_struct *lck2)
{
#if defined(DEVELOPER)
SMB_ASSERT(lck1->lock_flav == POSIX_LOCK);
SMB_ASSERT(lck2->lock_flav == POSIX_LOCK);
#endif
/* Ignore PENDING locks. */
if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
return False;
/* Read locks never conflict. */
if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) {
return False;
}
/* Locks on the same context con't conflict. Ignore fnum. */
if (brl_same_context(&lck1->context, &lck2->context)) {
return False;
}
/* One is read, the other write, or the context is different,
do they overlap ? */
return brl_overlap(lck1, lck2);
}
#if ZERO_ZERO
static bool brl_conflict1(const struct lock_struct *lck1,
const struct lock_struct *lck2)
{
if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
return False;
if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK) {
return False;
}
if (brl_same_context(&lck1->context, &lck2->context) &&
lck2->lock_type == READ_LOCK && lck1->fnum == lck2->fnum) {
return False;
}
if (lck2->start == 0 && lck2->size == 0 && lck1->size != 0) {
return True;
}
if (lck1->start >= (lck2->start + lck2->size) ||
lck2->start >= (lck1->start + lck1->size)) {
return False;
}
return True;
}
#endif
/****************************************************************************
Check to see if this lock conflicts, but ignore our own locks on the
same fnum only. This is the read/write lock check code path.
This is never used in the POSIX lock case.
****************************************************************************/
static bool brl_conflict_other(const struct lock_struct *lck1, const struct lock_struct *lck2)
{
if (IS_PENDING_LOCK(lck1->lock_type) || IS_PENDING_LOCK(lck2->lock_type))
return False;
if (lck1->lock_type == READ_LOCK && lck2->lock_type == READ_LOCK)
return False;
/* POSIX flavour locks never conflict here - this is only called
in the read/write path. */
if (lck1->lock_flav == POSIX_LOCK && lck2->lock_flav == POSIX_LOCK)
return False;
/*
* Incoming WRITE locks conflict with existing READ locks even
* if the context is the same. JRA. See LOCKTEST7 in smbtorture.
*/
if (!(lck2->lock_type == WRITE_LOCK && lck1->lock_type == READ_LOCK)) {
if (brl_same_context(&lck1->context, &lck2->context) &&
lck1->fnum == lck2->fnum)
return False;
}
return brl_overlap(lck1, lck2);
}
/****************************************************************************
Check if an unlock overlaps a pending lock.
****************************************************************************/
static bool brl_pending_overlap(const struct lock_struct *lock, const struct lock_struct *pend_lock)
{
if ((lock->start <= pend_lock->start) && (lock->start + lock->size > pend_lock->start))
return True;
if ((lock->start >= pend_lock->start) && (lock->start <= pend_lock->start + pend_lock->size))
return True;
return False;
}
/****************************************************************************
Amazingly enough, w2k3 "remembers" whether the last lock failure on a fnum
is the same as this one and changes its error code. I wonder if any
app depends on this ?
****************************************************************************/
NTSTATUS brl_lock_failed(files_struct *fsp, const struct lock_struct *lock, bool blocking_lock)
{
if (lock->start >= 0xEF000000 && (lock->start >> 63) == 0) {
/* 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 (!blocking_lock) {
fsp->last_lock_failure = *lock;
}
return NT_STATUS_FILE_LOCK_CONFLICT;
}
if (procid_equal(&lock->context.pid, &fsp->last_lock_failure.context.pid) &&
lock->context.tid == fsp->last_lock_failure.context.tid &&
lock->fnum == fsp->last_lock_failure.fnum &&
lock->start == fsp->last_lock_failure.start) {
return NT_STATUS_FILE_LOCK_CONFLICT;
}
if (!blocking_lock) {
fsp->last_lock_failure = *lock;
}
return NT_STATUS_LOCK_NOT_GRANTED;
}
/****************************************************************************
Open up the brlock.tdb database.
****************************************************************************/
void brl_init(bool read_only)
{
int tdb_flags;
if (brlock_db) {
return;
}
tdb_flags = TDB_DEFAULT|TDB_VOLATILE|TDB_CLEAR_IF_FIRST|TDB_INCOMPATIBLE_HASH;
if (!lp_clustering()) {
/*
* We can't use the SEQNUM trick to cache brlock
* entries in the clustering case because ctdb seqnum
* propagation has a delay.
*/
tdb_flags |= TDB_SEQNUM;
}
brlock_db = db_open(NULL, lock_path("brlock.tdb"),
lp_open_files_db_hash_size(), tdb_flags,
read_only?O_RDONLY:(O_RDWR|O_CREAT), 0644 );
if (!brlock_db) {
DEBUG(0,("Failed to open byte range locking database %s\n",
lock_path("brlock.tdb")));
return;
}
}
/****************************************************************************
Close down the brlock.tdb database.
****************************************************************************/
void brl_shutdown(void)
{
TALLOC_FREE(brlock_db);
}
#if ZERO_ZERO
/****************************************************************************
Compare two locks for sorting.
****************************************************************************/
static int lock_compare(const struct lock_struct *lck1,
const struct lock_struct *lck2)
{
if (lck1->start != lck2->start) {
return (lck1->start - lck2->start);
}
if (lck2->size != lck1->size) {
return ((int)lck1->size - (int)lck2->size);
}
return 0;
}
#endif
/****************************************************************************
Lock a range of bytes - Windows lock semantics.
****************************************************************************/
NTSTATUS brl_lock_windows_default(struct byte_range_lock *br_lck,
struct lock_struct *plock, bool blocking_lock)
{
unsigned int i;
files_struct *fsp = br_lck->fsp;
struct lock_struct *locks = br_lck->lock_data;
NTSTATUS status;
SMB_ASSERT(plock->lock_type != UNLOCK_LOCK);
if ((plock->start + plock->size - 1 < plock->start) &&
plock->size != 0) {
return NT_STATUS_INVALID_LOCK_RANGE;
}
for (i=0; i < br_lck->num_locks; i++) {
/* Do any Windows or POSIX locks conflict ? */
if (brl_conflict(&locks[i], plock)) {
/* Remember who blocked us. */
plock->context.smblctx = locks[i].context.smblctx;
return brl_lock_failed(fsp,plock,blocking_lock);
}
#if ZERO_ZERO
if (plock->start == 0 && plock->size == 0 &&
locks[i].size == 0) {
break;
}
#endif
}
if (!IS_PENDING_LOCK(plock->lock_type)) {
contend_level2_oplocks_begin(fsp, LEVEL2_CONTEND_WINDOWS_BRL);
}
/* We can get the Windows lock, now see if it needs to
be mapped into a lower level POSIX one, and if so can
we get it ? */
if (!IS_PENDING_LOCK(plock->lock_type) && lp_posix_locking(fsp->conn->params)) {
int errno_ret;
if (!set_posix_lock_windows_flavour(fsp,
plock->start,
plock->size,
plock->lock_type,
&plock->context,
locks,
br_lck->num_locks,
&errno_ret)) {
/* We don't know who blocked us. */
plock->context.smblctx = 0xFFFFFFFFFFFFFFFFLL;
if (errno_ret == EACCES || errno_ret == EAGAIN) {
status = NT_STATUS_FILE_LOCK_CONFLICT;
goto fail;
} else {
status = map_nt_error_from_unix(errno);
goto fail;
}
}
}
/* no conflicts - add it to the list of locks */
locks = (struct lock_struct *)SMB_REALLOC(locks, (br_lck->num_locks + 1) * sizeof(*locks));
if (!locks) {
status = NT_STATUS_NO_MEMORY;
goto fail;
}
memcpy(&locks[br_lck->num_locks], plock, sizeof(struct lock_struct));
br_lck->num_locks += 1;
br_lck->lock_data = locks;
br_lck->modified = True;
return NT_STATUS_OK;
fail:
if (!IS_PENDING_LOCK(plock->lock_type)) {
contend_level2_oplocks_end(fsp, LEVEL2_CONTEND_WINDOWS_BRL);
}
return status;
}
/****************************************************************************
Cope with POSIX range splits and merges.
****************************************************************************/
static unsigned int brlock_posix_split_merge(struct lock_struct *lck_arr, /* Output array. */
struct lock_struct *ex, /* existing lock. */
struct lock_struct *plock) /* proposed lock. */
{
bool lock_types_differ = (ex->lock_type != plock->lock_type);
/* We can't merge non-conflicting locks on different context - ignore fnum. */
if (!brl_same_context(&ex->context, &plock->context)) {
/* Just copy. */
memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
return 1;
}
/* We now know we have the same context. */
/* Did we overlap ? */
/*********************************************
+---------+
| ex |
+---------+
+-------+
| plock |
+-------+
OR....
+---------+
| ex |
+---------+
**********************************************/
if ( (ex->start > (plock->start + plock->size)) ||
(plock->start > (ex->start + ex->size))) {
/* No overlap with this lock - copy existing. */
memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
return 1;
}
/*********************************************
+---------------------------+
| ex |
+---------------------------+
+---------------------------+
| plock | -> replace with plock.
+---------------------------+
OR
+---------------+
| ex |
+---------------+
+---------------------------+
| plock | -> replace with plock.
+---------------------------+
**********************************************/
if ( (ex->start >= plock->start) &&
(ex->start + ex->size <= plock->start + plock->size) ) {
/* Replace - discard existing lock. */
return 0;
}
/*********************************************
Adjacent after.
+-------+
| ex |
+-------+
+---------------+
| plock |
+---------------+
BECOMES....
+---------------+-------+
| plock | ex | - different lock types.
+---------------+-------+
OR.... (merge)
+-----------------------+
| plock | - same lock type.
+-----------------------+
**********************************************/
if (plock->start + plock->size == ex->start) {
/* If the lock types are the same, we merge, if different, we
add the remainder of the old lock. */
if (lock_types_differ) {
/* Add existing. */
memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
return 1;
} else {
/* Merge - adjust incoming lock as we may have more
* merging to come. */
plock->size += ex->size;
return 0;
}
}
/*********************************************
Adjacent before.
+-------+
| ex |
+-------+
+---------------+
| plock |
+---------------+
BECOMES....
+-------+---------------+
| ex | plock | - different lock types
+-------+---------------+
OR.... (merge)
+-----------------------+
| plock | - same lock type.
+-----------------------+
**********************************************/
if (ex->start + ex->size == plock->start) {
/* If the lock types are the same, we merge, if different, we
add the existing lock. */
if (lock_types_differ) {
memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
return 1;
} else {
/* Merge - adjust incoming lock as we may have more
* merging to come. */
plock->start = ex->start;
plock->size += ex->size;
return 0;
}
}
/*********************************************
Overlap after.
+-----------------------+
| ex |
+-----------------------+
+---------------+
| plock |
+---------------+
OR
+----------------+
| ex |
+----------------+
+---------------+
| plock |
+---------------+
BECOMES....
+---------------+-------+
| plock | ex | - different lock types.
+---------------+-------+
OR.... (merge)
+-----------------------+
| plock | - same lock type.
+-----------------------+
**********************************************/
if ( (ex->start >= plock->start) &&
(ex->start <= plock->start + plock->size) &&
(ex->start + ex->size > plock->start + plock->size) ) {
/* If the lock types are the same, we merge, if different, we
add the remainder of the old lock. */
if (lock_types_differ) {
/* Add remaining existing. */
memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
/* Adjust existing start and size. */
lck_arr[0].start = plock->start + plock->size;
lck_arr[0].size = (ex->start + ex->size) - (plock->start + plock->size);
return 1;
} else {
/* Merge - adjust incoming lock as we may have more
* merging to come. */
plock->size += (ex->start + ex->size) - (plock->start + plock->size);
return 0;
}
}
/*********************************************
Overlap before.
+-----------------------+
| ex |
+-----------------------+
+---------------+
| plock |
+---------------+
OR
+-------------+
| ex |
+-------------+
+---------------+
| plock |
+---------------+
BECOMES....
+-------+---------------+
| ex | plock | - different lock types
+-------+---------------+
OR.... (merge)
+-----------------------+
| plock | - same lock type.
+-----------------------+
**********************************************/
if ( (ex->start < plock->start) &&
(ex->start + ex->size >= plock->start) &&
(ex->start + ex->size <= plock->start + plock->size) ) {
/* If the lock types are the same, we merge, if different, we
add the truncated old lock. */
if (lock_types_differ) {
memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
/* Adjust existing size. */
lck_arr[0].size = plock->start - ex->start;
return 1;
} else {
/* Merge - adjust incoming lock as we may have more
* merging to come. MUST ADJUST plock SIZE FIRST ! */
plock->size += (plock->start - ex->start);
plock->start = ex->start;
return 0;
}
}
/*********************************************
Complete overlap.
+---------------------------+
| ex |
+---------------------------+
+---------+
| plock |
+---------+
BECOMES.....
+-------+---------+---------+
| ex | plock | ex | - different lock types.
+-------+---------+---------+
OR
+---------------------------+
| plock | - same lock type.
+---------------------------+
**********************************************/
if ( (ex->start < plock->start) && (ex->start + ex->size > plock->start + plock->size) ) {
if (lock_types_differ) {
/* We have to split ex into two locks here. */
memcpy(&lck_arr[0], ex, sizeof(struct lock_struct));
memcpy(&lck_arr[1], ex, sizeof(struct lock_struct));
/* Adjust first existing size. */
lck_arr[0].size = plock->start - ex->start;
/* Adjust second existing start and size. */
lck_arr[1].start = plock->start + plock->size;
lck_arr[1].size = (ex->start + ex->size) - (plock->start + plock->size);
return 2;
} else {
/* Just eat the existing locks, merge them into plock. */
plock->start = ex->start;
plock->size = ex->size;
return 0;
}
}
/* Never get here. */
smb_panic("brlock_posix_split_merge");
/* Notreached. */
/* Keep some compilers happy. */
return 0;
}
/****************************************************************************
Lock a range of bytes - POSIX lock semantics.
We must cope with range splits and merges.
****************************************************************************/
static NTSTATUS brl_lock_posix(struct messaging_context *msg_ctx,
struct byte_range_lock *br_lck,
struct lock_struct *plock)
{
unsigned int i, count, posix_count;
struct lock_struct *locks = br_lck->lock_data;
struct lock_struct *tp;
bool signal_pending_read = False;
bool break_oplocks = false;
NTSTATUS status;
/* No zero-zero locks for POSIX. */
if (plock->start == 0 && plock->size == 0) {
return NT_STATUS_INVALID_PARAMETER;
}
/* Don't allow 64-bit lock wrap. */
if (plock->start + plock->size - 1 < plock->start) {
return NT_STATUS_INVALID_PARAMETER;
}
/* The worst case scenario here is we have to split an
existing POSIX lock range into two, and add our lock,
so we need at most 2 more entries. */
tp = SMB_MALLOC_ARRAY(struct lock_struct, (br_lck->num_locks + 2));
if (!tp) {
return NT_STATUS_NO_MEMORY;
}
count = posix_count = 0;
for (i=0; i < br_lck->num_locks; i++) {
struct lock_struct *curr_lock = &locks[i];
/* If we have a pending read lock, a lock downgrade should
trigger a lock re-evaluation. */
if (curr_lock->lock_type == PENDING_READ_LOCK &&
brl_pending_overlap(plock, curr_lock)) {
signal_pending_read = True;
}
if (curr_lock->lock_flav == WINDOWS_LOCK) {
/* Do any Windows flavour locks conflict ? */
if (brl_conflict(curr_lock, plock)) {
/* No games with error messages. */
SAFE_FREE(tp);
/* Remember who blocked us. */
plock->context.smblctx = curr_lock->context.smblctx;
return NT_STATUS_FILE_LOCK_CONFLICT;
}
/* Just copy the Windows lock into the new array. */
memcpy(&tp[count], curr_lock, sizeof(struct lock_struct));
count++;
} else {
unsigned int tmp_count = 0;
/* POSIX conflict semantics are different. */
if (brl_conflict_posix(curr_lock, plock)) {
/* Can't block ourselves with POSIX locks. */
/* No games with error messages. */
SAFE_FREE(tp);
/* Remember who blocked us. */
plock->context.smblctx = curr_lock->context.smblctx;
return NT_STATUS_FILE_LOCK_CONFLICT;
}
/* Work out overlaps. */
tmp_count += brlock_posix_split_merge(&tp[count], curr_lock, plock);
posix_count += tmp_count;
count += tmp_count;
}
}
/*
* Break oplocks while we hold a brl. Since lock() and unlock() calls
* are not symetric with POSIX semantics, we cannot guarantee our
* contend_level2_oplocks_begin/end calls will be acquired and
* released one-for-one as with Windows semantics. Therefore we only
* call contend_level2_oplocks_begin if this is the first POSIX brl on
* the file.
*/
break_oplocks = (!IS_PENDING_LOCK(plock->lock_type) &&
posix_count == 0);
if (break_oplocks) {
contend_level2_oplocks_begin(br_lck->fsp,
LEVEL2_CONTEND_POSIX_BRL);
}
/* Try and add the lock in order, sorted by lock start. */
for (i=0; i < count; i++) {
struct lock_struct *curr_lock = &tp[i];
if (curr_lock->start <= plock->start) {
continue;
}
}
if (i < count) {
memmove(&tp[i+1], &tp[i],
(count - i)*sizeof(struct lock_struct));
}
memcpy(&tp[i], plock, sizeof(struct lock_struct));
count++;
/* We can get the POSIX lock, now see if it needs to
be mapped into a lower level POSIX one, and if so can
we get it ? */
if (!IS_PENDING_LOCK(plock->lock_type) && lp_posix_locking(br_lck->fsp->conn->params)) {
int errno_ret;
/* The lower layer just needs to attempt to
get the system POSIX lock. We've weeded out
any conflicts above. */
if (!set_posix_lock_posix_flavour(br_lck->fsp,
plock->start,
plock->size,
plock->lock_type,
&errno_ret)) {
/* We don't know who blocked us. */
plock->context.smblctx = 0xFFFFFFFFFFFFFFFFLL;
if (errno_ret == EACCES || errno_ret == EAGAIN) {
SAFE_FREE(tp);
status = NT_STATUS_FILE_LOCK_CONFLICT;
goto fail;
} else {
SAFE_FREE(tp);
status = map_nt_error_from_unix(errno);
goto fail;
}
}
}
/* If we didn't use all the allocated size,
* Realloc so we don't leak entries per lock call. */
if (count < br_lck->num_locks + 2) {
tp = (struct lock_struct *)SMB_REALLOC(tp, count * sizeof(*locks));
if (!tp) {
status = NT_STATUS_NO_MEMORY;
goto fail;
}
}
br_lck->num_locks = count;
SAFE_FREE(br_lck->lock_data);
br_lck->lock_data = tp;
locks = tp;
br_lck->modified = True;
/* A successful downgrade from write to read lock can trigger a lock
re-evalutation where waiting readers can now proceed. */
if (signal_pending_read) {
/* Send unlock messages to any pending read waiters that overlap. */
for (i=0; i < br_lck->num_locks; i++) {
struct lock_struct *pend_lock = &locks[i];
/* Ignore non-pending locks. */
if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
continue;
}
if (pend_lock->lock_type == PENDING_READ_LOCK &&
brl_pending_overlap(plock, pend_lock)) {
DEBUG(10,("brl_lock_posix: sending unlock message to pid %s\n",
procid_str_static(&pend_lock->context.pid )));
messaging_send(msg_ctx, pend_lock->context.pid,
MSG_SMB_UNLOCK, &data_blob_null);
}
}
}
return NT_STATUS_OK;
fail:
if (break_oplocks) {
contend_level2_oplocks_end(br_lck->fsp,
LEVEL2_CONTEND_POSIX_BRL);
}
return status;
}
NTSTATUS smb_vfs_call_brl_lock_windows(struct vfs_handle_struct *handle,
struct byte_range_lock *br_lck,
struct lock_struct *plock,
bool blocking_lock,
struct blocking_lock_record *blr)
{
VFS_FIND(brl_lock_windows);
return handle->fns->brl_lock_windows(handle, br_lck, plock,
blocking_lock, blr);
}
/****************************************************************************
Lock a range of bytes.
****************************************************************************/
NTSTATUS brl_lock(struct messaging_context *msg_ctx,
struct byte_range_lock *br_lck,
uint64_t smblctx,
struct server_id pid,
br_off start,
br_off size,
enum brl_type lock_type,
enum brl_flavour lock_flav,
bool blocking_lock,
uint64_t *psmblctx,
struct blocking_lock_record *blr)
{
NTSTATUS ret;
struct lock_struct lock;
#if !ZERO_ZERO
if (start == 0 && size == 0) {
DEBUG(0,("client sent 0/0 lock - please report this\n"));
}
#endif
#ifdef DEVELOPER
/* Quieten valgrind on test. */
memset(&lock, '\0', sizeof(lock));
#endif
lock.context.smblctx = smblctx;
lock.context.pid = pid;
lock.context.tid = br_lck->fsp->conn->cnum;
lock.start = start;
lock.size = size;
lock.fnum = br_lck->fsp->fnum;
lock.lock_type = lock_type;
lock.lock_flav = lock_flav;
if (lock_flav == WINDOWS_LOCK) {
ret = SMB_VFS_BRL_LOCK_WINDOWS(br_lck->fsp->conn, br_lck,
&lock, blocking_lock, blr);
} else {
ret = brl_lock_posix(msg_ctx, br_lck, &lock);
}
#if ZERO_ZERO
/* sort the lock list */
TYPESAFE_QSORT(br_lck->lock_data, (size_t)br_lck->num_locks, lock_compare);
#endif
/* If we're returning an error, return who blocked us. */
if (!NT_STATUS_IS_OK(ret) && psmblctx) {
*psmblctx = lock.context.smblctx;
}
return ret;
}
/****************************************************************************
Unlock a range of bytes - Windows semantics.
****************************************************************************/
bool brl_unlock_windows_default(struct messaging_context *msg_ctx,
struct byte_range_lock *br_lck,
const struct lock_struct *plock)
{
unsigned int i, j;
struct lock_struct *locks = br_lck->lock_data;
enum brl_type deleted_lock_type = READ_LOCK; /* shut the compiler up.... */
SMB_ASSERT(plock->lock_type == UNLOCK_LOCK);
#if ZERO_ZERO
/* Delete write locks by preference... The lock list
is sorted in the zero zero case. */
for (i = 0; i < br_lck->num_locks; i++) {
struct lock_struct *lock = &locks[i];
if (lock->lock_type == WRITE_LOCK &&
brl_same_context(&lock->context, &plock->context) &&
lock->fnum == plock->fnum &&
lock->lock_flav == WINDOWS_LOCK &&
lock->start == plock->start &&
lock->size == plock->size) {
/* found it - delete it */
deleted_lock_type = lock->lock_type;
break;
}
}
if (i != br_lck->num_locks) {
/* We found it - don't search again. */
goto unlock_continue;
}
#endif
for (i = 0; i < br_lck->num_locks; i++) {
struct lock_struct *lock = &locks[i];
if (IS_PENDING_LOCK(lock->lock_type)) {
continue;
}
/* Only remove our own locks that match in start, size, and flavour. */
if (brl_same_context(&lock->context, &plock->context) &&
lock->fnum == plock->fnum &&
lock->lock_flav == WINDOWS_LOCK &&
lock->start == plock->start &&
lock->size == plock->size ) {
deleted_lock_type = lock->lock_type;
break;
}
}
if (i == br_lck->num_locks) {
/* we didn't find it */
return False;
}
#if ZERO_ZERO
unlock_continue:
#endif
/* Actually delete the lock. */
if (i < br_lck->num_locks - 1) {
memmove(&locks[i], &locks[i+1],
sizeof(*locks)*((br_lck->num_locks-1) - i));
}
br_lck->num_locks -= 1;
br_lck->modified = True;
/* Unlock the underlying POSIX regions. */
if(lp_posix_locking(br_lck->fsp->conn->params)) {
release_posix_lock_windows_flavour(br_lck->fsp,
plock->start,
plock->size,
deleted_lock_type,
&plock->context,
locks,
br_lck->num_locks);
}
/* Send unlock messages to any pending waiters that overlap. */
for (j=0; j < br_lck->num_locks; j++) {
struct lock_struct *pend_lock = &locks[j];
/* Ignore non-pending locks. */
if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
continue;
}
/* We could send specific lock info here... */
if (brl_pending_overlap(plock, pend_lock)) {
DEBUG(10,("brl_unlock: sending unlock message to pid %s\n",
procid_str_static(&pend_lock->context.pid )));
messaging_send(msg_ctx, pend_lock->context.pid,
MSG_SMB_UNLOCK, &data_blob_null);
}
}
contend_level2_oplocks_end(br_lck->fsp, LEVEL2_CONTEND_WINDOWS_BRL);
return True;
}
/****************************************************************************
Unlock a range of bytes - POSIX semantics.
****************************************************************************/
static bool brl_unlock_posix(struct messaging_context *msg_ctx,
struct byte_range_lock *br_lck,
struct lock_struct *plock)
{
unsigned int i, j, count;
struct lock_struct *tp;
struct lock_struct *locks = br_lck->lock_data;
bool overlap_found = False;
/* No zero-zero locks for POSIX. */
if (plock->start == 0 && plock->size == 0) {
return False;
}
/* Don't allow 64-bit lock wrap. */
if (plock->start + plock->size < plock->start ||
plock->start + plock->size < plock->size) {
DEBUG(10,("brl_unlock_posix: lock wrap\n"));
return False;
}
/* The worst case scenario here is we have to split an
existing POSIX lock range into two, so we need at most
1 more entry. */
tp = SMB_MALLOC_ARRAY(struct lock_struct, (br_lck->num_locks + 1));
if (!tp) {
DEBUG(10,("brl_unlock_posix: malloc fail\n"));
return False;
}
count = 0;
for (i = 0; i < br_lck->num_locks; i++) {
struct lock_struct *lock = &locks[i];
unsigned int tmp_count;
/* Only remove our own locks - ignore fnum. */
if (IS_PENDING_LOCK(lock->lock_type) ||
!brl_same_context(&lock->context, &plock->context)) {
memcpy(&tp[count], lock, sizeof(struct lock_struct));
count++;
continue;
}
if (lock->lock_flav == WINDOWS_LOCK) {
/* Do any Windows flavour locks conflict ? */
if (brl_conflict(lock, plock)) {
SAFE_FREE(tp);
return false;
}
/* Just copy the Windows lock into the new array. */
memcpy(&tp[count], lock, sizeof(struct lock_struct));
count++;
continue;
}
/* Work out overlaps. */
tmp_count = brlock_posix_split_merge(&tp[count], lock, plock);
if (tmp_count == 0) {
/* plock overlapped the existing lock completely,
or replaced it. Don't copy the existing lock. */
overlap_found = true;
} else if (tmp_count == 1) {
/* Either no overlap, (simple copy of existing lock) or
* an overlap of an existing lock. */
/* If the lock changed size, we had an overlap. */
if (tp[count].size != lock->size) {
overlap_found = true;
}
count += tmp_count;
} else if (tmp_count == 2) {
/* We split a lock range in two. */
overlap_found = true;
count += tmp_count;
/* Optimisation... */
/* We know we're finished here as we can't overlap any
more POSIX locks. Copy the rest of the lock array. */
if (i < br_lck->num_locks - 1) {
memcpy(&tp[count], &locks[i+1],
sizeof(*locks)*((br_lck->num_locks-1) - i));
count += ((br_lck->num_locks-1) - i);
}
break;
}
}
if (!overlap_found) {
/* Just ignore - no change. */
SAFE_FREE(tp);
DEBUG(10,("brl_unlock_posix: No overlap - unlocked.\n"));
return True;
}
/* Unlock any POSIX regions. */
if(lp_posix_locking(br_lck->fsp->conn->params)) {
release_posix_lock_posix_flavour(br_lck->fsp,
plock->start,
plock->size,
&plock->context,
tp,
count);
}
/* Realloc so we don't leak entries per unlock call. */
if (count) {
tp = (struct lock_struct *)SMB_REALLOC(tp, count * sizeof(*locks));
if (!tp) {
DEBUG(10,("brl_unlock_posix: realloc fail\n"));
return False;
}
} else {
/* We deleted the last lock. */
SAFE_FREE(tp);
tp = NULL;
}
contend_level2_oplocks_end(br_lck->fsp,
LEVEL2_CONTEND_POSIX_BRL);
br_lck->num_locks = count;
SAFE_FREE(br_lck->lock_data);
locks = tp;
br_lck->lock_data = tp;
br_lck->modified = True;
/* Send unlock messages to any pending waiters that overlap. */
for (j=0; j < br_lck->num_locks; j++) {
struct lock_struct *pend_lock = &locks[j];
/* Ignore non-pending locks. */
if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
continue;
}
/* We could send specific lock info here... */
if (brl_pending_overlap(plock, pend_lock)) {
DEBUG(10,("brl_unlock: sending unlock message to pid %s\n",
procid_str_static(&pend_lock->context.pid )));
messaging_send(msg_ctx, pend_lock->context.pid,
MSG_SMB_UNLOCK, &data_blob_null);
}
}
return True;
}
bool smb_vfs_call_brl_unlock_windows(struct vfs_handle_struct *handle,
struct messaging_context *msg_ctx,
struct byte_range_lock *br_lck,
const struct lock_struct *plock)
{
VFS_FIND(brl_unlock_windows);
return handle->fns->brl_unlock_windows(handle, msg_ctx, br_lck, plock);
}
/****************************************************************************
Unlock a range of bytes.
****************************************************************************/
bool brl_unlock(struct messaging_context *msg_ctx,
struct byte_range_lock *br_lck,
uint64_t smblctx,
struct server_id pid,
br_off start,
br_off size,
enum brl_flavour lock_flav)
{
struct lock_struct lock;
lock.context.smblctx = smblctx;
lock.context.pid = pid;
lock.context.tid = br_lck->fsp->conn->cnum;
lock.start = start;
lock.size = size;
lock.fnum = br_lck->fsp->fnum;
lock.lock_type = UNLOCK_LOCK;
lock.lock_flav = lock_flav;
if (lock_flav == WINDOWS_LOCK) {
return SMB_VFS_BRL_UNLOCK_WINDOWS(br_lck->fsp->conn, msg_ctx,
br_lck, &lock);
} else {
return brl_unlock_posix(msg_ctx, br_lck, &lock);
}
}
/****************************************************************************
Test if we could add a lock if we wanted to.
Returns True if the region required is currently unlocked, False if locked.
****************************************************************************/
bool brl_locktest(struct byte_range_lock *br_lck,
uint64_t smblctx,
struct server_id pid,
br_off start,
br_off size,
enum brl_type lock_type,
enum brl_flavour lock_flav)
{
bool ret = True;
unsigned int i;
struct lock_struct lock;
const struct lock_struct *locks = br_lck->lock_data;
files_struct *fsp = br_lck->fsp;
lock.context.smblctx = smblctx;
lock.context.pid = pid;
lock.context.tid = br_lck->fsp->conn->cnum;
lock.start = start;
lock.size = size;
lock.fnum = fsp->fnum;
lock.lock_type = lock_type;
lock.lock_flav = lock_flav;
/* Make sure existing locks don't conflict */
for (i=0; i < br_lck->num_locks; i++) {
/*
* Our own locks don't conflict.
*/
if (brl_conflict_other(&locks[i], &lock)) {
return False;
}
}
/*
* There is no lock held by an SMB daemon, check to
* see if there is a POSIX lock from a UNIX or NFS process.
* This only conflicts with Windows locks, not POSIX locks.
*/
if(lp_posix_locking(fsp->conn->params) && (lock_flav == WINDOWS_LOCK)) {
ret = is_posix_locked(fsp, &start, &size, &lock_type, WINDOWS_LOCK);
DEBUG(10,("brl_locktest: posix start=%.0f len=%.0f %s for fnum %d file %s\n",
(double)start, (double)size, ret ? "locked" : "unlocked",
fsp->fnum, fsp_str_dbg(fsp)));
/* We need to return the inverse of is_posix_locked. */
ret = !ret;
}
/* no conflicts - we could have added it */
return ret;
}
/****************************************************************************
Query for existing locks.
****************************************************************************/
NTSTATUS brl_lockquery(struct byte_range_lock *br_lck,
uint64_t *psmblctx,
struct server_id pid,
br_off *pstart,
br_off *psize,
enum brl_type *plock_type,
enum brl_flavour lock_flav)
{
unsigned int i;
struct lock_struct lock;
const struct lock_struct *locks = br_lck->lock_data;
files_struct *fsp = br_lck->fsp;
lock.context.smblctx = *psmblctx;
lock.context.pid = pid;
lock.context.tid = br_lck->fsp->conn->cnum;
lock.start = *pstart;
lock.size = *psize;
lock.fnum = fsp->fnum;
lock.lock_type = *plock_type;
lock.lock_flav = lock_flav;
/* Make sure existing locks don't conflict */
for (i=0; i < br_lck->num_locks; i++) {
const struct lock_struct *exlock = &locks[i];
bool conflict = False;
if (exlock->lock_flav == WINDOWS_LOCK) {
conflict = brl_conflict(exlock, &lock);
} else {
conflict = brl_conflict_posix(exlock, &lock);
}
if (conflict) {
*psmblctx = exlock->context.smblctx;
*pstart = exlock->start;
*psize = exlock->size;
*plock_type = exlock->lock_type;
return NT_STATUS_LOCK_NOT_GRANTED;
}
}
/*
* There is no lock held by an SMB daemon, check to
* see if there is a POSIX lock from a UNIX or NFS process.
*/
if(lp_posix_locking(fsp->conn->params)) {
bool ret = is_posix_locked(fsp, pstart, psize, plock_type, POSIX_LOCK);
DEBUG(10,("brl_lockquery: posix start=%.0f len=%.0f %s for fnum %d file %s\n",
(double)*pstart, (double)*psize, ret ? "locked" : "unlocked",
fsp->fnum, fsp_str_dbg(fsp)));
if (ret) {
/* Hmmm. No clue what to set smblctx to - use -1. */
*psmblctx = 0xFFFFFFFFFFFFFFFFLL;
return NT_STATUS_LOCK_NOT_GRANTED;
}
}
return NT_STATUS_OK;
}
bool smb_vfs_call_brl_cancel_windows(struct vfs_handle_struct *handle,
struct byte_range_lock *br_lck,
struct lock_struct *plock,
struct blocking_lock_record *blr)
{
VFS_FIND(brl_cancel_windows);
return handle->fns->brl_cancel_windows(handle, br_lck, plock, blr);
}
/****************************************************************************
Remove a particular pending lock.
****************************************************************************/
bool brl_lock_cancel(struct byte_range_lock *br_lck,
uint64_t smblctx,
struct server_id pid,
br_off start,
br_off size,
enum brl_flavour lock_flav,
struct blocking_lock_record *blr)
{
bool ret;
struct lock_struct lock;
lock.context.smblctx = smblctx;
lock.context.pid = pid;
lock.context.tid = br_lck->fsp->conn->cnum;
lock.start = start;
lock.size = size;
lock.fnum = br_lck->fsp->fnum;
lock.lock_flav = lock_flav;
/* lock.lock_type doesn't matter */
if (lock_flav == WINDOWS_LOCK) {
ret = SMB_VFS_BRL_CANCEL_WINDOWS(br_lck->fsp->conn, br_lck,
&lock, blr);
} else {
ret = brl_lock_cancel_default(br_lck, &lock);
}
return ret;
}
bool brl_lock_cancel_default(struct byte_range_lock *br_lck,
struct lock_struct *plock)
{
unsigned int i;
struct lock_struct *locks = br_lck->lock_data;
SMB_ASSERT(plock);
for (i = 0; i < br_lck->num_locks; i++) {
struct lock_struct *lock = &locks[i];
/* For pending locks we *always* care about the fnum. */
if (brl_same_context(&lock->context, &plock->context) &&
lock->fnum == plock->fnum &&
IS_PENDING_LOCK(lock->lock_type) &&
lock->lock_flav == plock->lock_flav &&
lock->start == plock->start &&
lock->size == plock->size) {
break;
}
}
if (i == br_lck->num_locks) {
/* Didn't find it. */
return False;
}
if (i < br_lck->num_locks - 1) {
/* Found this particular pending lock - delete it */
memmove(&locks[i], &locks[i+1],
sizeof(*locks)*((br_lck->num_locks-1) - i));
}
br_lck->num_locks -= 1;
br_lck->modified = True;
return True;
}
/****************************************************************************
Remove any locks associated with a open file.
We return True if this process owns any other Windows locks on this
fd and so we should not immediately close the fd.
****************************************************************************/
void brl_close_fnum(struct messaging_context *msg_ctx,
struct byte_range_lock *br_lck)
{
files_struct *fsp = br_lck->fsp;
uint16 tid = fsp->conn->cnum;
int fnum = fsp->fnum;
unsigned int i, j, dcount=0;
int num_deleted_windows_locks = 0;
struct lock_struct *locks = br_lck->lock_data;
struct server_id pid = sconn_server_id(fsp->conn->sconn);
bool unlock_individually = False;
bool posix_level2_contention_ended = false;
if(lp_posix_locking(fsp->conn->params)) {
/* Check if there are any Windows locks associated with this dev/ino
pair that are not this fnum. If so we need to call unlock on each
one in order to release the system POSIX locks correctly. */
for (i=0; i < br_lck->num_locks; i++) {
struct lock_struct *lock = &locks[i];
if (!procid_equal(&lock->context.pid, &pid)) {
continue;
}
if (lock->lock_type != READ_LOCK && lock->lock_type != WRITE_LOCK) {
continue; /* Ignore pending. */
}
if (lock->context.tid != tid || lock->fnum != fnum) {
unlock_individually = True;
break;
}
}
if (unlock_individually) {
struct lock_struct *locks_copy;
unsigned int num_locks_copy;
/* Copy the current lock array. */
if (br_lck->num_locks) {
locks_copy = (struct lock_struct *)TALLOC_MEMDUP(br_lck, locks, br_lck->num_locks * sizeof(struct lock_struct));
if (!locks_copy) {
smb_panic("brl_close_fnum: talloc failed");
}
} else {
locks_copy = NULL;
}
num_locks_copy = br_lck->num_locks;
for (i=0; i < num_locks_copy; i++) {
struct lock_struct *lock = &locks_copy[i];
if (lock->context.tid == tid && procid_equal(&lock->context.pid, &pid) &&
(lock->fnum == fnum)) {
brl_unlock(msg_ctx,
br_lck,
lock->context.smblctx,
pid,
lock->start,
lock->size,
lock->lock_flav);
}
}
return;
}
}
/* We can bulk delete - any POSIX locks will be removed when the fd closes. */
/* Remove any existing locks for this fnum (or any fnum if they're POSIX). */
for (i=0; i < br_lck->num_locks; i++) {
struct lock_struct *lock = &locks[i];
bool del_this_lock = False;
if (lock->context.tid == tid && procid_equal(&lock->context.pid, &pid)) {
if ((lock->lock_flav == WINDOWS_LOCK) && (lock->fnum == fnum)) {
del_this_lock = True;
num_deleted_windows_locks++;
contend_level2_oplocks_end(br_lck->fsp,
LEVEL2_CONTEND_WINDOWS_BRL);
} else if (lock->lock_flav == POSIX_LOCK) {
del_this_lock = True;
/* Only end level2 contention once for posix */
if (!posix_level2_contention_ended) {
posix_level2_contention_ended = true;
contend_level2_oplocks_end(br_lck->fsp,
LEVEL2_CONTEND_POSIX_BRL);
}
}
}
if (del_this_lock) {
/* Send unlock messages to any pending waiters that overlap. */
for (j=0; j < br_lck->num_locks; j++) {
struct lock_struct *pend_lock = &locks[j];
/* Ignore our own or non-pending locks. */
if (!IS_PENDING_LOCK(pend_lock->lock_type)) {
continue;
}
/* Optimisation - don't send to this fnum as we're
closing it. */
if (pend_lock->context.tid == tid &&
procid_equal(&pend_lock->context.pid, &pid) &&
pend_lock->fnum == fnum) {
continue;
}
/* We could send specific lock info here... */
if (brl_pending_overlap(lock, pend_lock)) {
messaging_send(msg_ctx, pend_lock->context.pid,
MSG_SMB_UNLOCK, &data_blob_null);
}
}
/* found it - delete it */
if (br_lck->num_locks > 1 && i < br_lck->num_locks - 1) {
memmove(&locks[i], &locks[i+1],
sizeof(*locks)*((br_lck->num_locks-1) - i));
}
br_lck->num_locks--;
br_lck->modified = True;
i--;
dcount++;
}
}
if(lp_posix_locking(fsp->conn->params) && num_deleted_windows_locks) {
/* Reduce the Windows lock POSIX reference count on this dev/ino pair. */
reduce_windows_lock_ref_count(fsp, num_deleted_windows_locks);
}
}
/****************************************************************************
Ensure this set of lock entries is valid.
****************************************************************************/
static bool validate_lock_entries(unsigned int *pnum_entries, struct lock_struct **pplocks)
{
unsigned int i;
unsigned int num_valid_entries = 0;
struct lock_struct *locks = *pplocks;
for (i = 0; i < *pnum_entries; i++) {
struct lock_struct *lock_data = &locks[i];
if (!serverid_exists(&lock_data->context.pid)) {
/* This process no longer exists - mark this
entry as invalid by zeroing it. */
ZERO_STRUCTP(lock_data);
} else {
num_valid_entries++;
}
}
if (num_valid_entries != *pnum_entries) {
struct lock_struct *new_lock_data = NULL;
if (num_valid_entries) {
new_lock_data = SMB_MALLOC_ARRAY(struct lock_struct, num_valid_entries);
if (!new_lock_data) {
DEBUG(3, ("malloc fail\n"));
return False;
}
num_valid_entries = 0;
for (i = 0; i < *pnum_entries; i++) {
struct lock_struct *lock_data = &locks[i];
if (lock_data->context.smblctx &&
lock_data->context.tid) {
/* Valid (nonzero) entry - copy it. */
memcpy(&new_lock_data[num_valid_entries],
lock_data, sizeof(struct lock_struct));
num_valid_entries++;
}
}
}
SAFE_FREE(*pplocks);
*pplocks = new_lock_data;
*pnum_entries = num_valid_entries;
}
return True;
}
struct brl_forall_cb {
void (*fn)(struct file_id id, struct server_id pid,
enum brl_type lock_type,
enum brl_flavour lock_flav,
br_off start, br_off size,
void *private_data);
void *private_data;
};
/****************************************************************************
Traverse the whole database with this function, calling traverse_callback
on each lock.
****************************************************************************/
static int traverse_fn(struct db_record *rec, void *state)
{
struct brl_forall_cb *cb = (struct brl_forall_cb *)state;
struct lock_struct *locks;
struct file_id *key;
unsigned int i;
unsigned int num_locks = 0;
unsigned int orig_num_locks = 0;
/* In a traverse function we must make a copy of
dbuf before modifying it. */
locks = (struct lock_struct *)memdup(rec->value.dptr,
rec->value.dsize);
if (!locks) {
return -1; /* Terminate traversal. */
}
key = (struct file_id *)rec->key.dptr;
orig_num_locks = num_locks = rec->value.dsize/sizeof(*locks);
/* Ensure the lock db is clean of entries from invalid processes. */
if (!validate_lock_entries(&num_locks, &locks)) {
SAFE_FREE(locks);
return -1; /* Terminate traversal */
}
if (orig_num_locks != num_locks) {
if (num_locks) {
TDB_DATA data;
data.dptr = (uint8_t *)locks;
data.dsize = num_locks*sizeof(struct lock_struct);
rec->store(rec, data, TDB_REPLACE);
} else {
rec->delete_rec(rec);
}
}
if (cb->fn) {
for ( i=0; ifn(*key,
locks[i].context.pid,
locks[i].lock_type,
locks[i].lock_flav,
locks[i].start,
locks[i].size,
cb->private_data);
}
}
SAFE_FREE(locks);
return 0;
}
/*******************************************************************
Call the specified function on each lock in the database.
********************************************************************/
int brl_forall(void (*fn)(struct file_id id, struct server_id pid,
enum brl_type lock_type,
enum brl_flavour lock_flav,
br_off start, br_off size,
void *private_data),
void *private_data)
{
struct brl_forall_cb cb;
if (!brlock_db) {
return 0;
}
cb.fn = fn;
cb.private_data = private_data;
return brlock_db->traverse(brlock_db, traverse_fn, &cb);
}
/*******************************************************************
Store a potentially modified set of byte range lock data back into
the database.
Unlock the record.
********************************************************************/
static void byte_range_lock_flush(struct byte_range_lock *br_lck)
{
if (br_lck->read_only) {
SMB_ASSERT(!br_lck->modified);
}
if (!br_lck->modified) {
goto done;
}
if (br_lck->num_locks == 0) {
/* No locks - delete this entry. */
NTSTATUS status = br_lck->record->delete_rec(br_lck->record);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(0, ("delete_rec returned %s\n",
nt_errstr(status)));
smb_panic("Could not delete byte range lock entry");
}
} else {
TDB_DATA data;
NTSTATUS status;
data.dptr = (uint8 *)br_lck->lock_data;
data.dsize = br_lck->num_locks * sizeof(struct lock_struct);
status = br_lck->record->store(br_lck->record, data,
TDB_REPLACE);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(0, ("store returned %s\n", nt_errstr(status)));
smb_panic("Could not store byte range mode entry");
}
}
done:
br_lck->read_only = true;
br_lck->modified = false;
TALLOC_FREE(br_lck->record);
}
static int byte_range_lock_destructor(struct byte_range_lock *br_lck)
{
byte_range_lock_flush(br_lck);
SAFE_FREE(br_lck->lock_data);
return 0;
}
/*******************************************************************
Fetch a set of byte range lock data from the database.
Leave the record locked.
TALLOC_FREE(brl) will release the lock in the destructor.
********************************************************************/
static struct byte_range_lock *brl_get_locks_internal(TALLOC_CTX *mem_ctx,
files_struct *fsp, bool read_only)
{
TDB_DATA key, data;
struct byte_range_lock *br_lck = TALLOC_P(mem_ctx, struct byte_range_lock);
bool do_read_only = read_only;
if (br_lck == NULL) {
return NULL;
}
br_lck->fsp = fsp;
br_lck->num_locks = 0;
br_lck->modified = False;
br_lck->key = fsp->file_id;
key.dptr = (uint8 *)&br_lck->key;
key.dsize = sizeof(struct file_id);
if (!fsp->lockdb_clean) {
/* We must be read/write to clean
the dead entries. */
do_read_only = false;
}
if (do_read_only) {
if (brlock_db->fetch(brlock_db, br_lck, key, &data) == -1) {
DEBUG(3, ("Could not fetch byte range lock record\n"));
TALLOC_FREE(br_lck);
return NULL;
}
br_lck->record = NULL;
} else {
br_lck->record = brlock_db->fetch_locked(brlock_db, br_lck, key);
if (br_lck->record == NULL) {
DEBUG(3, ("Could not lock byte range lock entry\n"));
TALLOC_FREE(br_lck);
return NULL;
}
data = br_lck->record->value;
}
br_lck->read_only = do_read_only;
br_lck->lock_data = NULL;
talloc_set_destructor(br_lck, byte_range_lock_destructor);
br_lck->num_locks = data.dsize / sizeof(struct lock_struct);
if (br_lck->num_locks != 0) {
br_lck->lock_data = SMB_MALLOC_ARRAY(struct lock_struct,
br_lck->num_locks);
if (br_lck->lock_data == NULL) {
DEBUG(0, ("malloc failed\n"));
TALLOC_FREE(br_lck);
return NULL;
}
memcpy(br_lck->lock_data, data.dptr, data.dsize);
}
if (!fsp->lockdb_clean) {
int orig_num_locks = br_lck->num_locks;
/* This is the first time we've accessed this. */
/* Go through and ensure all entries exist - remove any that don't. */
/* Makes the lockdb self cleaning at low cost. */
if (!validate_lock_entries(&br_lck->num_locks,
&br_lck->lock_data)) {
SAFE_FREE(br_lck->lock_data);
TALLOC_FREE(br_lck);
return NULL;
}
/* Ensure invalid locks are cleaned up in the destructor. */
if (orig_num_locks != br_lck->num_locks) {
br_lck->modified = True;
}
/* Mark the lockdb as "clean" as seen from this open file. */
fsp->lockdb_clean = True;
}
if (DEBUGLEVEL >= 10) {
unsigned int i;
struct lock_struct *locks = br_lck->lock_data;
DEBUG(10,("brl_get_locks_internal: %u current locks on file_id %s\n",
br_lck->num_locks,
file_id_string_tos(&fsp->file_id)));
for( i = 0; i < br_lck->num_locks; i++) {
print_lock_struct(i, &locks[i]);
}
}
if (do_read_only != read_only) {
/*
* this stores the record and gets rid of
* the write lock that is needed for a cleanup
*/
byte_range_lock_flush(br_lck);
}
return br_lck;
}
struct byte_range_lock *brl_get_locks(TALLOC_CTX *mem_ctx,
files_struct *fsp)
{
return brl_get_locks_internal(mem_ctx, fsp, False);
}
struct byte_range_lock *brl_get_locks_readonly(files_struct *fsp)
{
struct byte_range_lock *br_lock;
if (lp_clustering()) {
return brl_get_locks_internal(talloc_tos(), fsp, true);
}
if ((fsp->brlock_rec != NULL)
&& (brlock_db->get_seqnum(brlock_db) == fsp->brlock_seqnum)) {
return fsp->brlock_rec;
}
TALLOC_FREE(fsp->brlock_rec);
br_lock = brl_get_locks_internal(talloc_tos(), fsp, true);
if (br_lock == NULL) {
return NULL;
}
fsp->brlock_seqnum = brlock_db->get_seqnum(brlock_db);
fsp->brlock_rec = talloc_move(fsp, &br_lock);
return fsp->brlock_rec;
}
struct brl_revalidate_state {
ssize_t array_size;
uint32 num_pids;
struct server_id *pids;
};
/*
* Collect PIDs of all processes with pending entries
*/
static void brl_revalidate_collect(struct file_id id, struct server_id pid,
enum brl_type lock_type,
enum brl_flavour lock_flav,
br_off start, br_off size,
void *private_data)
{
struct brl_revalidate_state *state =
(struct brl_revalidate_state *)private_data;
if (!IS_PENDING_LOCK(lock_type)) {
return;
}
add_to_large_array(state, sizeof(pid), (void *)&pid,
&state->pids, &state->num_pids,
&state->array_size);
}
/*
* qsort callback to sort the processes
*/
static int compare_procids(const void *p1, const void *p2)
{
const struct server_id *i1 = (struct server_id *)p1;
const struct server_id *i2 = (struct server_id *)p2;
if (i1->pid < i2->pid) return -1;
if (i2->pid > i2->pid) return 1;
return 0;
}
/*
* Send a MSG_SMB_UNLOCK message to all processes with pending byte range
* locks so that they retry. Mainly used in the cluster code after a node has
* died.
*
* Done in two steps to avoid double-sends: First we collect all entries in an
* array, then qsort that array and only send to non-dupes.
*/
static void brl_revalidate(struct messaging_context *msg_ctx,
void *private_data,
uint32_t msg_type,
struct server_id server_id,
DATA_BLOB *data)
{
struct brl_revalidate_state *state;
uint32 i;
struct server_id last_pid;
if (!(state = TALLOC_ZERO_P(NULL, struct brl_revalidate_state))) {
DEBUG(0, ("talloc failed\n"));
return;
}
brl_forall(brl_revalidate_collect, state);
if (state->array_size == -1) {
DEBUG(0, ("talloc failed\n"));
goto done;
}
if (state->num_pids == 0) {
goto done;
}
TYPESAFE_QSORT(state->pids, state->num_pids, compare_procids);
ZERO_STRUCT(last_pid);
for (i=0; inum_pids; i++) {
if (procid_equal(&last_pid, &state->pids[i])) {
/*
* We've seen that one already
*/
continue;
}
messaging_send(msg_ctx, state->pids[i], MSG_SMB_UNLOCK,
&data_blob_null);
last_pid = state->pids[i];
}
done:
TALLOC_FREE(state);
return;
}
void brl_register_msgs(struct messaging_context *msg_ctx)
{
messaging_register(msg_ctx, NULL, MSG_SMB_BRL_VALIDATE,
brl_revalidate);
}