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samba-mirror/source3/smbd/oplock.c

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/*
Unix SMB/CIFS implementation.
oplock processing
Copyright (C) Andrew Tridgell 1992-1998
Copyright (C) Jeremy Allison 1998 - 2001
Copyright (C) Volker Lendecke 2005
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/>.
*/
#define DBGC_CLASS DBGC_LOCKING
#include "includes.h"
/* Current number of oplocks we have outstanding. */
static int32 exclusive_oplocks_open = 0;
static int32 level_II_oplocks_open = 0;
bool global_client_failed_oplock_break = False;
extern uint32 global_client_caps;
static struct kernel_oplocks *koplocks;
/****************************************************************************
Get the number of current exclusive oplocks.
****************************************************************************/
int32 get_number_of_exclusive_open_oplocks(void)
{
return exclusive_oplocks_open;
}
/****************************************************************************
Return True if an oplock message is pending.
****************************************************************************/
bool oplock_message_waiting(fd_set *fds)
{
if (koplocks && koplocks->msg_waiting(fds)) {
return True;
}
return False;
}
/****************************************************************************
Find out if there are any kernel oplock messages waiting and process them
if so. pfds is the fd_set from the main select loop (which contains any
kernel oplock fd if that's what the system uses (IRIX). If may be NULL if
we're calling this in a shutting down state.
****************************************************************************/
void process_kernel_oplocks(struct messaging_context *msg_ctx, fd_set *pfds)
{
/*
* We need to check for kernel oplocks before going into the select
* here, as the EINTR generated by the linux kernel oplock may have
* already been eaten. JRA.
*/
if (!koplocks) {
return;
}
while (koplocks->msg_waiting(pfds)) {
files_struct *fsp;
char msg[MSG_SMB_KERNEL_BREAK_SIZE];
fsp = koplocks->receive_message(pfds);
if (fsp == NULL) {
DEBUG(3, ("Kernel oplock message announced, but none "
"received\n"));
return;
}
/* Put the kernel break info into the message. */
push_file_id_16(msg, &fsp->file_id);
SIVAL(msg,16,fsp->fh->gen_id);
/* Don't need to be root here as we're only ever
sending to ourselves. */
messaging_send_buf(msg_ctx, procid_self(),
MSG_SMB_KERNEL_BREAK,
(uint8 *)&msg, MSG_SMB_KERNEL_BREAK_SIZE);
}
}
/****************************************************************************
Attempt to set an oplock on a file. Always succeeds if kernel oplocks are
disabled (just sets flags). Returns True if oplock set.
****************************************************************************/
bool set_file_oplock(files_struct *fsp, int oplock_type)
{
if ((fsp->oplock_type != NO_OPLOCK) &&
(fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
koplocks &&
!koplocks->set_oplock(fsp, oplock_type)) {
return False;
}
fsp->oplock_type = oplock_type;
fsp->sent_oplock_break = NO_BREAK_SENT;
if (oplock_type == LEVEL_II_OPLOCK) {
level_II_oplocks_open++;
} else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
exclusive_oplocks_open++;
}
DEBUG(5,("set_file_oplock: granted oplock on file %s, %s/%lu, "
"tv_sec = %x, tv_usec = %x\n",
fsp->fsp_name, file_id_string_tos(&fsp->file_id),
fsp->fh->gen_id, (int)fsp->open_time.tv_sec,
(int)fsp->open_time.tv_usec ));
return True;
}
/****************************************************************************
Attempt to release an oplock on a file. Decrements oplock count.
****************************************************************************/
void release_file_oplock(files_struct *fsp)
{
if ((fsp->oplock_type != NO_OPLOCK) &&
(fsp->oplock_type != FAKE_LEVEL_II_OPLOCK) &&
koplocks) {
koplocks->release_oplock(fsp);
}
if (fsp->oplock_type == LEVEL_II_OPLOCK) {
level_II_oplocks_open--;
} else if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
exclusive_oplocks_open--;
}
SMB_ASSERT(exclusive_oplocks_open>=0);
SMB_ASSERT(level_II_oplocks_open>=0);
if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
/* This doesn't matter for close. */
fsp->oplock_type = FAKE_LEVEL_II_OPLOCK;
} else {
fsp->oplock_type = NO_OPLOCK;
}
fsp->sent_oplock_break = NO_BREAK_SENT;
flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
TALLOC_FREE(fsp->oplock_timeout);
}
/****************************************************************************
Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
****************************************************************************/
static void downgrade_file_oplock(files_struct *fsp)
{
if (koplocks) {
koplocks->release_oplock(fsp);
}
fsp->oplock_type = LEVEL_II_OPLOCK;
exclusive_oplocks_open--;
level_II_oplocks_open++;
fsp->sent_oplock_break = NO_BREAK_SENT;
}
/****************************************************************************
Remove a file oplock. Copes with level II and exclusive.
Locks then unlocks the share mode lock. Client can decide to go directly
to none even if a "break-to-level II" was sent.
****************************************************************************/
bool remove_oplock(files_struct *fsp)
{
bool ret;
struct share_mode_lock *lck;
/* Remove the oplock flag from the sharemode. */
lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
NULL);
if (lck == NULL) {
DEBUG(0,("remove_oplock: failed to lock share entry for "
"file %s\n", fsp->fsp_name ));
return False;
}
ret = remove_share_oplock(lck, fsp);
if (!ret) {
DEBUG(0,("remove_oplock: failed to remove share oplock for "
"file %s fnum %d, %s\n",
fsp->fsp_name, fsp->fnum, file_id_string_tos(&fsp->file_id)));
}
release_file_oplock(fsp);
TALLOC_FREE(lck);
return ret;
}
/*
* Deal with a reply when a break-to-level II was sent.
*/
bool downgrade_oplock(files_struct *fsp)
{
bool ret;
struct share_mode_lock *lck;
lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
NULL);
if (lck == NULL) {
DEBUG(0,("downgrade_oplock: failed to lock share entry for "
"file %s\n", fsp->fsp_name ));
return False;
}
ret = downgrade_share_oplock(lck, fsp);
if (!ret) {
DEBUG(0,("downgrade_oplock: failed to downgrade share oplock "
"for file %s fnum %d, file_id %s\n",
fsp->fsp_name, fsp->fnum, file_id_string_tos(&fsp->file_id)));
}
downgrade_file_oplock(fsp);
TALLOC_FREE(lck);
return ret;
}
/****************************************************************************
Return the fd (if any) used for receiving oplock notifications.
****************************************************************************/
int oplock_notify_fd(void)
{
if (koplocks) {
return koplocks->notification_fd;
}
return -1;
}
/****************************************************************************
Set up an oplock break message.
****************************************************************************/
static char *new_break_smb_message(TALLOC_CTX *mem_ctx,
files_struct *fsp, uint8 cmd)
{
char *result = TALLOC_ARRAY(mem_ctx, char, smb_size + 8*2 + 0);
if (result == NULL) {
DEBUG(0, ("talloc failed\n"));
return NULL;
}
memset(result,'\0',smb_size);
srv_set_message(result,8,0,true);
SCVAL(result,smb_com,SMBlockingX);
SSVAL(result,smb_tid,fsp->conn->cnum);
SSVAL(result,smb_pid,0xFFFF);
SSVAL(result,smb_uid,0);
SSVAL(result,smb_mid,0xFFFF);
SCVAL(result,smb_vwv0,0xFF);
SSVAL(result,smb_vwv2,fsp->fnum);
SCVAL(result,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
SCVAL(result,smb_vwv3+1,cmd);
return result;
}
/****************************************************************************
Function to do the waiting before sending a local break.
****************************************************************************/
static void wait_before_sending_break(void)
{
long wait_time = (long)lp_oplock_break_wait_time();
if (wait_time) {
smb_msleep(wait_time);
}
}
/****************************************************************************
Ensure that we have a valid oplock.
****************************************************************************/
static files_struct *initial_break_processing(struct file_id id, unsigned long file_id)
{
files_struct *fsp = NULL;
if( DEBUGLVL( 3 ) ) {
dbgtext( "initial_break_processing: called for %s/%u\n",
file_id_string_tos(&id), (int)file_id);
dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
exclusive_oplocks_open, level_II_oplocks_open );
}
/*
* We need to search the file open table for the
* entry containing this dev and inode, and ensure
* we have an oplock on it.
*/
fsp = file_find_dif(id, file_id);
if(fsp == NULL) {
/* The file could have been closed in the meantime - return success. */
if( DEBUGLVL( 3 ) ) {
dbgtext( "initial_break_processing: cannot find open file with " );
dbgtext( "file_id %s gen_id = %lu", file_id_string_tos(&id), file_id);
dbgtext( "allowing break to succeed.\n" );
}
return NULL;
}
/* Ensure we have an oplock on the file */
/*
* There is a potential race condition in that an oplock could
* have been broken due to another udp request, and yet there are
* still oplock break messages being sent in the udp message
* queue for this file. So return true if we don't have an oplock,
* as we may have just freed it.
*/
if(fsp->oplock_type == NO_OPLOCK) {
if( DEBUGLVL( 3 ) ) {
dbgtext( "initial_break_processing: file %s ", fsp->fsp_name );
dbgtext( "(file_id = %s gen_id = %lu) has no oplock.\n",
file_id_string_tos(&id), fsp->fh->gen_id );
dbgtext( "Allowing break to succeed regardless.\n" );
}
return NULL;
}
return fsp;
}
static void oplock_timeout_handler(struct event_context *ctx,
struct timed_event *te,
struct timeval now,
void *private_data)
{
files_struct *fsp = (files_struct *)private_data;
/* Remove the timed event handler. */
TALLOC_FREE(fsp->oplock_timeout);
DEBUG(0, ("Oplock break failed for file %s -- replying anyway\n", fsp->fsp_name));
global_client_failed_oplock_break = True;
remove_oplock(fsp);
reply_to_oplock_break_requests(fsp);
}
/*******************************************************************
Add a timeout handler waiting for the client reply.
*******************************************************************/
static void add_oplock_timeout_handler(files_struct *fsp)
{
if (fsp->oplock_timeout != NULL) {
DEBUG(0, ("Logic problem -- have an oplock event hanging "
"around\n"));
}
fsp->oplock_timeout =
event_add_timed(smbd_event_context(), NULL,
timeval_current_ofs(OPLOCK_BREAK_TIMEOUT, 0),
oplock_timeout_handler, fsp);
if (fsp->oplock_timeout == NULL) {
DEBUG(0, ("Could not add oplock timeout handler\n"));
}
}
/*******************************************************************
This handles the case of a write triggering a break to none
message on a level2 oplock.
When we get this message we may be in any of three states :
NO_OPLOCK, LEVEL_II, FAKE_LEVEL2. We only send a message to
the client for LEVEL2.
*******************************************************************/
static void process_oplock_async_level2_break_message(struct messaging_context *msg_ctx,
void *private_data,
uint32_t msg_type,
struct server_id src,
DATA_BLOB *data)
{
struct share_mode_entry msg;
files_struct *fsp;
char *break_msg;
bool sign_state;
if (data->data == NULL) {
DEBUG(0, ("Got NULL buffer\n"));
return;
}
if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
return;
}
/* De-linearize incoming message. */
message_to_share_mode_entry(&msg, (char *)data->data);
DEBUG(10, ("Got oplock async level 2 break message from pid %d: %s/%lu\n",
(int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id));
fsp = initial_break_processing(msg.id, msg.share_file_id);
if (fsp == NULL) {
/* We hit a race here. Break messages are sent, and before we
* get to process this message, we have closed the file.
* No need to reply as this is an async message. */
DEBUG(3, ("process_oplock_async_level2_break_message: Did not find fsp, ignoring\n"));
return;
}
if (fsp->oplock_type == NO_OPLOCK) {
/* We already got a "break to none" message and we've handled it.
* just ignore. */
DEBUG(3, ("process_oplock_async_level2_break_message: already broken to none, ignoring.\n"));
return;
}
if (fsp->oplock_type == FAKE_LEVEL_II_OPLOCK) {
/* Don't tell the client, just downgrade. */
DEBUG(3, ("process_oplock_async_level2_break_message: downgrading fake level 2 oplock.\n"));
remove_oplock(fsp);
return;
}
/* Ensure we're really at level2 state. */
SMB_ASSERT(fsp->oplock_type == LEVEL_II_OPLOCK);
DEBUG(10,("process_oplock_async_level2_break_message: sending break to "
"none message for fid %d, file %s\n",
fsp->fnum,
fsp->fsp_name));
/* Now send a break to none message to our client. */
break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
if (break_msg == NULL) {
exit_server("Could not talloc break_msg\n");
}
/* Need to wait before sending a break message if we sent ourselves this message. */
if (procid_to_pid(&src) == sys_getpid()) {
wait_before_sending_break();
}
/* Save the server smb signing state. */
sign_state = srv_oplock_set_signing(False);
show_msg(break_msg);
if (!srv_send_smb(smbd_server_fd(),
break_msg,
IS_CONN_ENCRYPTED(fsp->conn))) {
exit_server_cleanly("oplock_break: srv_send_smb failed.");
}
/* Restore the sign state to what it was. */
srv_oplock_set_signing(sign_state);
TALLOC_FREE(break_msg);
/* Async level2 request, don't send a reply, just remove the oplock. */
remove_oplock(fsp);
}
/*******************************************************************
This handles the generic oplock break message from another smbd.
*******************************************************************/
static void process_oplock_break_message(struct messaging_context *msg_ctx,
void *private_data,
uint32_t msg_type,
struct server_id src,
DATA_BLOB *data)
{
struct share_mode_entry msg;
files_struct *fsp;
char *break_msg;
bool break_to_level2 = False;
bool sign_state;
if (data->data == NULL) {
DEBUG(0, ("Got NULL buffer\n"));
return;
}
if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
return;
}
/* De-linearize incoming message. */
message_to_share_mode_entry(&msg, (char *)data->data);
DEBUG(10, ("Got oplock break message from pid %d: %s/%lu\n",
(int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id));
fsp = initial_break_processing(msg.id, msg.share_file_id);
if (fsp == NULL) {
/* a We hit race here. Break messages are sent, and before we
* get to process this message, we have closed the file. Reply
* with 'ok, oplock broken' */
DEBUG(3, ("Did not find fsp\n"));
/* We just send the same message back. */
messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
(uint8 *)data->data,
MSG_SMB_SHARE_MODE_ENTRY_SIZE);
return;
}
if (fsp->sent_oplock_break != NO_BREAK_SENT) {
/* Remember we have to inform the requesting PID when the
* client replies */
msg.pid = src;
ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
&fsp->pending_break_messages,
&fsp->num_pending_break_messages);
return;
}
if (EXCLUSIVE_OPLOCK_TYPE(msg.op_type) &&
!EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
DEBUG(3, ("Already downgraded oplock on %s: %s\n",
file_id_string_tos(&fsp->file_id),
fsp->fsp_name));
/* We just send the same message back. */
messaging_send_buf(msg_ctx, src, MSG_SMB_BREAK_RESPONSE,
(uint8 *)data->data,
MSG_SMB_SHARE_MODE_ENTRY_SIZE);
return;
}
if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
!(msg.op_type & FORCE_OPLOCK_BREAK_TO_NONE) &&
!koplocks && /* NOTE: we force levelII off for kernel oplocks -
* this will change when it is supported */
lp_level2_oplocks(SNUM(fsp->conn))) {
break_to_level2 = True;
}
break_msg = new_break_smb_message(NULL, fsp, break_to_level2 ?
OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
if (break_msg == NULL) {
exit_server("Could not talloc break_msg\n");
}
/* Need to wait before sending a break message if we sent ourselves this message. */
if (procid_to_pid(&src) == sys_getpid()) {
wait_before_sending_break();
}
/* Save the server smb signing state. */
sign_state = srv_oplock_set_signing(False);
show_msg(break_msg);
if (!srv_send_smb(smbd_server_fd(),
break_msg,
IS_CONN_ENCRYPTED(fsp->conn))) {
exit_server_cleanly("oplock_break: srv_send_smb failed.");
}
/* Restore the sign state to what it was. */
srv_oplock_set_signing(sign_state);
TALLOC_FREE(break_msg);
fsp->sent_oplock_break = break_to_level2 ? LEVEL_II_BREAK_SENT:BREAK_TO_NONE_SENT;
msg.pid = src;
ADD_TO_ARRAY(NULL, struct share_mode_entry, msg,
&fsp->pending_break_messages,
&fsp->num_pending_break_messages);
add_oplock_timeout_handler(fsp);
}
/*******************************************************************
This handles the kernel oplock break message.
*******************************************************************/
static void process_kernel_oplock_break(struct messaging_context *msg_ctx,
void *private_data,
uint32_t msg_type,
struct server_id src,
DATA_BLOB *data)
{
struct file_id id;
unsigned long file_id;
files_struct *fsp;
char *break_msg;
bool sign_state;
if (data->data == NULL) {
DEBUG(0, ("Got NULL buffer\n"));
return;
}
if (data->length != MSG_SMB_KERNEL_BREAK_SIZE) {
DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
return;
}
/* Pull the data from the message. */
pull_file_id_16((char *)data->data, &id);
file_id = (unsigned long)IVAL(data->data, 16);
DEBUG(10, ("Got kernel oplock break message from pid %d: %s/%u\n",
(int)procid_to_pid(&src), file_id_string_tos(&id),
(unsigned int)file_id));
fsp = initial_break_processing(id, file_id);
if (fsp == NULL) {
DEBUG(3, ("Got a kernel oplock break message for a file "
"I don't know about\n"));
return;
}
if (fsp->sent_oplock_break != NO_BREAK_SENT) {
/* This is ok, kernel oplocks come in completely async */
DEBUG(3, ("Got a kernel oplock request while waiting for a "
"break reply\n"));
return;
}
break_msg = new_break_smb_message(NULL, fsp, OPLOCKLEVEL_NONE);
if (break_msg == NULL) {
exit_server("Could not talloc break_msg\n");
}
/* Save the server smb signing state. */
sign_state = srv_oplock_set_signing(False);
show_msg(break_msg);
if (!srv_send_smb(smbd_server_fd(),
break_msg,
IS_CONN_ENCRYPTED(fsp->conn))) {
exit_server_cleanly("oplock_break: srv_send_smb failed.");
}
/* Restore the sign state to what it was. */
srv_oplock_set_signing(sign_state);
TALLOC_FREE(break_msg);
fsp->sent_oplock_break = BREAK_TO_NONE_SENT;
add_oplock_timeout_handler(fsp);
}
void reply_to_oplock_break_requests(files_struct *fsp)
{
int i;
for (i=0; i<fsp->num_pending_break_messages; i++) {
struct share_mode_entry *e = &fsp->pending_break_messages[i];
char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
share_mode_entry_to_message(msg, e);
messaging_send_buf(smbd_messaging_context(), e->pid,
MSG_SMB_BREAK_RESPONSE,
(uint8 *)msg,
MSG_SMB_SHARE_MODE_ENTRY_SIZE);
}
SAFE_FREE(fsp->pending_break_messages);
fsp->num_pending_break_messages = 0;
if (fsp->oplock_timeout != NULL) {
/* Remove the timed event handler. */
TALLOC_FREE(fsp->oplock_timeout);
fsp->oplock_timeout = NULL;
}
return;
}
static void process_oplock_break_response(struct messaging_context *msg_ctx,
void *private_data,
uint32_t msg_type,
struct server_id src,
DATA_BLOB *data)
{
struct share_mode_entry msg;
if (data->data == NULL) {
DEBUG(0, ("Got NULL buffer\n"));
return;
}
if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
DEBUG(0, ("Got invalid msg len %u\n",
(unsigned int)data->length));
return;
}
/* De-linearize incoming message. */
message_to_share_mode_entry(&msg, (char *)data->data);
DEBUG(10, ("Got oplock break response from pid %d: %s/%lu mid %u\n",
(int)procid_to_pid(&src), file_id_string_tos(&msg.id), msg.share_file_id,
(unsigned int)msg.op_mid));
/* Here's the hack from open.c, store the mid in the 'port' field */
schedule_deferred_open_smb_message(msg.op_mid);
}
static void process_open_retry_message(struct messaging_context *msg_ctx,
void *private_data,
uint32_t msg_type,
struct server_id src,
DATA_BLOB *data)
{
struct share_mode_entry msg;
if (data->data == NULL) {
DEBUG(0, ("Got NULL buffer\n"));
return;
}
if (data->length != MSG_SMB_SHARE_MODE_ENTRY_SIZE) {
DEBUG(0, ("Got invalid msg len %d\n", (int)data->length));
return;
}
/* De-linearize incoming message. */
message_to_share_mode_entry(&msg, (char *)data->data);
DEBUG(10, ("Got open retry msg from pid %d: %s mid %u\n",
(int)procid_to_pid(&src), file_id_string_tos(&msg.id),
(unsigned int)msg.op_mid));
schedule_deferred_open_smb_message(msg.op_mid);
}
/****************************************************************************
This function is called on any file modification or lock request. If a file
is level 2 oplocked then it must tell all other level 2 holders to break to
none.
****************************************************************************/
void release_level_2_oplocks_on_change(files_struct *fsp)
{
int i;
struct share_mode_lock *lck;
/*
* If this file is level II oplocked then we need
* to grab the shared memory lock and inform all
* other files with a level II lock that they need
* to flush their read caches. We keep the lock over
* the shared memory area whilst doing this.
*/
if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
return;
lck = get_share_mode_lock(talloc_tos(), fsp->file_id, NULL, NULL,
NULL);
if (lck == NULL) {
DEBUG(0,("release_level_2_oplocks_on_change: failed to lock "
"share mode entry for file %s.\n", fsp->fsp_name ));
return;
}
DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
lck->num_share_modes ));
for(i = 0; i < lck->num_share_modes; i++) {
struct share_mode_entry *share_entry = &lck->share_modes[i];
char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];
if (!is_valid_share_mode_entry(share_entry)) {
continue;
}
/*
* As there could have been multiple writes waiting at the
* lock_share_entry gate we may not be the first to
* enter. Hence the state of the op_types in the share mode
* entries may be partly NO_OPLOCK and partly LEVEL_II or FAKE_LEVEL_II
* oplock. It will do no harm to re-send break messages to
* those smbd's that are still waiting their turn to remove
* their LEVEL_II state, and also no harm to ignore existing
* NO_OPLOCK states. JRA.
*/
DEBUG(10,("release_level_2_oplocks_on_change: "
"share_entry[%i]->op_type == %d\n",
i, share_entry->op_type ));
if (share_entry->op_type == NO_OPLOCK) {
continue;
}
/* Paranoia .... */
if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
DEBUG(0,("release_level_2_oplocks_on_change: PANIC. "
"share mode entry %d is an exlusive "
"oplock !\n", i ));
TALLOC_FREE(lck);
abort();
}
share_mode_entry_to_message(msg, share_entry);
/*
* Deal with a race condition when breaking level2
* oplocks. Don't send all the messages and release
* the lock, this allows someone else to come in and
* get a level2 lock before any of the messages are
* processed, and thus miss getting a break message.
* Ensure at least one entry (the one we're breaking)
* is processed immediately under the lock and becomes
* set as NO_OPLOCK to stop any waiter getting a level2.
* Bugid #5980.
*/
if (procid_is_me(&share_entry->pid)) {
DATA_BLOB blob = data_blob_const(msg,
MSG_SMB_SHARE_MODE_ENTRY_SIZE);
process_oplock_async_level2_break_message(smbd_messaging_context(),
NULL,
MSG_SMB_ASYNC_LEVEL2_BREAK,
share_entry->pid,
&blob);
} else {
messaging_send_buf(smbd_messaging_context(),
share_entry->pid,
MSG_SMB_ASYNC_LEVEL2_BREAK,
(uint8 *)msg,
MSG_SMB_SHARE_MODE_ENTRY_SIZE);
}
}
/* We let the message receivers handle removing the oplock state
in the share mode lock db. */
TALLOC_FREE(lck);
}
/****************************************************************************
Linearize a share mode entry struct to an internal oplock break message.
****************************************************************************/
void share_mode_entry_to_message(char *msg, const struct share_mode_entry *e)
{
SIVAL(msg,0,(uint32)e->pid.pid);
SSVAL(msg,4,e->op_mid);
SSVAL(msg,6,e->op_type);
SIVAL(msg,8,e->access_mask);
SIVAL(msg,12,e->share_access);
SIVAL(msg,16,e->private_options);
SIVAL(msg,20,(uint32)e->time.tv_sec);
SIVAL(msg,24,(uint32)e->time.tv_usec);
push_file_id_16(msg+28, &e->id);
SIVAL(msg,44,e->share_file_id);
SIVAL(msg,48,e->uid);
SSVAL(msg,52,e->flags);
#ifdef CLUSTER_SUPPORT
SIVAL(msg,54,e->pid.vnn);
#endif
}
/****************************************************************************
De-linearize an internal oplock break message to a share mode entry struct.
****************************************************************************/
void message_to_share_mode_entry(struct share_mode_entry *e, char *msg)
{
e->pid.pid = (pid_t)IVAL(msg,0);
e->op_mid = SVAL(msg,4);
e->op_type = SVAL(msg,6);
e->access_mask = IVAL(msg,8);
e->share_access = IVAL(msg,12);
e->private_options = IVAL(msg,16);
e->time.tv_sec = (time_t)IVAL(msg,20);
e->time.tv_usec = (int)IVAL(msg,24);
pull_file_id_16(msg+28, &e->id);
e->share_file_id = (unsigned long)IVAL(msg,44);
e->uid = (uint32)IVAL(msg,48);
e->flags = (uint16)SVAL(msg,52);
#ifdef CLUSTER_SUPPORT
e->pid.vnn = IVAL(msg,54);
#endif
}
/****************************************************************************
Setup oplocks for this process.
****************************************************************************/
bool init_oplocks(struct messaging_context *msg_ctx)
{
DEBUG(3,("init_oplocks: initializing messages.\n"));
messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_REQUEST,
process_oplock_break_message);
messaging_register(msg_ctx, NULL, MSG_SMB_ASYNC_LEVEL2_BREAK,
process_oplock_async_level2_break_message);
messaging_register(msg_ctx, NULL, MSG_SMB_BREAK_RESPONSE,
process_oplock_break_response);
messaging_register(msg_ctx, NULL, MSG_SMB_KERNEL_BREAK,
process_kernel_oplock_break);
messaging_register(msg_ctx, NULL, MSG_SMB_OPEN_RETRY,
process_open_retry_message);
if (lp_kernel_oplocks()) {
#if HAVE_KERNEL_OPLOCKS_IRIX
koplocks = irix_init_kernel_oplocks();
#elif HAVE_KERNEL_OPLOCKS_LINUX
koplocks = linux_init_kernel_oplocks();
#endif
}
return True;
}