linux/fs/smbfs/smbiod.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

344 lines
7.5 KiB
C

/*
* smbiod.c
*
* Copyright (C) 2000, Charles Loep / Corel Corp.
* Copyright (C) 2001, Urban Widmark
*/
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/file.h>
#include <linux/dcache.h>
#include <linux/module.h>
#include <linux/net.h>
#include <linux/kthread.h>
#include <net/ip.h>
#include <linux/smb_fs.h>
#include <linux/smbno.h>
#include <linux/smb_mount.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include "smb_debug.h"
#include "request.h"
#include "proto.h"
enum smbiod_state {
SMBIOD_DEAD,
SMBIOD_STARTING,
SMBIOD_RUNNING,
};
static enum smbiod_state smbiod_state = SMBIOD_DEAD;
static struct task_struct *smbiod_thread;
static DECLARE_WAIT_QUEUE_HEAD(smbiod_wait);
static LIST_HEAD(smb_servers);
static DEFINE_SPINLOCK(servers_lock);
#define SMBIOD_DATA_READY (1<<0)
static unsigned long smbiod_flags;
static int smbiod(void *);
static int smbiod_start(void);
/*
* called when there's work for us to do
*/
void smbiod_wake_up(void)
{
if (smbiod_state == SMBIOD_DEAD)
return;
set_bit(SMBIOD_DATA_READY, &smbiod_flags);
wake_up_interruptible(&smbiod_wait);
}
/*
* start smbiod if none is running
*/
static int smbiod_start(void)
{
struct task_struct *tsk;
int err = 0;
if (smbiod_state != SMBIOD_DEAD)
return 0;
smbiod_state = SMBIOD_STARTING;
__module_get(THIS_MODULE);
spin_unlock(&servers_lock);
tsk = kthread_run(smbiod, NULL, "smbiod");
if (IS_ERR(tsk)) {
err = PTR_ERR(tsk);
module_put(THIS_MODULE);
}
spin_lock(&servers_lock);
if (err < 0) {
smbiod_state = SMBIOD_DEAD;
smbiod_thread = NULL;
} else {
smbiod_state = SMBIOD_RUNNING;
smbiod_thread = tsk;
}
return err;
}
/*
* register a server & start smbiod if necessary
*/
int smbiod_register_server(struct smb_sb_info *server)
{
int ret;
spin_lock(&servers_lock);
list_add(&server->entry, &smb_servers);
VERBOSE("%p\n", server);
ret = smbiod_start();
spin_unlock(&servers_lock);
return ret;
}
/*
* Unregister a server
* Must be called with the server lock held.
*/
void smbiod_unregister_server(struct smb_sb_info *server)
{
spin_lock(&servers_lock);
list_del_init(&server->entry);
VERBOSE("%p\n", server);
spin_unlock(&servers_lock);
smbiod_wake_up();
smbiod_flush(server);
}
void smbiod_flush(struct smb_sb_info *server)
{
struct list_head *tmp, *n;
struct smb_request *req;
list_for_each_safe(tmp, n, &server->xmitq) {
req = list_entry(tmp, struct smb_request, rq_queue);
req->rq_errno = -EIO;
list_del_init(&req->rq_queue);
smb_rput(req);
wake_up_interruptible(&req->rq_wait);
}
list_for_each_safe(tmp, n, &server->recvq) {
req = list_entry(tmp, struct smb_request, rq_queue);
req->rq_errno = -EIO;
list_del_init(&req->rq_queue);
smb_rput(req);
wake_up_interruptible(&req->rq_wait);
}
}
/*
* Wake up smbmount and make it reconnect to the server.
* This must be called with the server locked.
*
* FIXME: add smbconnect version to this
*/
int smbiod_retry(struct smb_sb_info *server)
{
struct list_head *head;
struct smb_request *req;
struct pid *pid = get_pid(server->conn_pid);
int result = 0;
VERBOSE("state: %d\n", server->state);
if (server->state == CONN_VALID || server->state == CONN_RETRYING)
goto out;
smb_invalidate_inodes(server);
/*
* Some requests are meaningless after a retry, so we abort them.
* One example are all requests using 'fileid' since the files are
* closed on retry.
*/
head = server->xmitq.next;
while (head != &server->xmitq) {
req = list_entry(head, struct smb_request, rq_queue);
head = head->next;
req->rq_bytes_sent = 0;
if (req->rq_flags & SMB_REQ_NORETRY) {
VERBOSE("aborting request %p on xmitq\n", req);
req->rq_errno = -EIO;
list_del_init(&req->rq_queue);
smb_rput(req);
wake_up_interruptible(&req->rq_wait);
}
}
/*
* FIXME: test the code for retrying request we already sent
*/
head = server->recvq.next;
while (head != &server->recvq) {
req = list_entry(head, struct smb_request, rq_queue);
head = head->next;
#if 0
if (req->rq_flags & SMB_REQ_RETRY) {
/* must move the request to the xmitq */
VERBOSE("retrying request %p on recvq\n", req);
list_move(&req->rq_queue, &server->xmitq);
continue;
}
#endif
VERBOSE("aborting request %p on recvq\n", req);
/* req->rq_rcls = ???; */ /* FIXME: set smb error code too? */
req->rq_errno = -EIO;
list_del_init(&req->rq_queue);
smb_rput(req);
wake_up_interruptible(&req->rq_wait);
}
smb_close_socket(server);
if (!pid) {
/* FIXME: this is fatal, umount? */
printk(KERN_ERR "smb_retry: no connection process\n");
server->state = CONN_RETRIED;
goto out;
}
/*
* Change state so that only one retry per server will be started.
*/
server->state = CONN_RETRYING;
/*
* Note: use the "priv" flag, as a user process may need to reconnect.
*/
result = kill_pid(pid, SIGUSR1, 1);
if (result) {
/* FIXME: this is most likely fatal, umount? */
printk(KERN_ERR "smb_retry: signal failed [%d]\n", result);
goto out;
}
VERBOSE("signalled pid %d\n", pid_nr(pid));
/* FIXME: The retried requests should perhaps get a "time boost". */
out:
put_pid(pid);
return result;
}
/*
* Currently handles lockingX packets.
*/
static void smbiod_handle_request(struct smb_sb_info *server)
{
PARANOIA("smbiod got a request ... and we don't implement oplocks!\n");
server->rstate = SMB_RECV_DROP;
}
/*
* Do some IO for one server.
*/
static void smbiod_doio(struct smb_sb_info *server)
{
int result;
int maxwork = 7;
if (server->state != CONN_VALID)
goto out;
do {
result = smb_request_recv(server);
if (result < 0) {
server->state = CONN_INVALID;
smbiod_retry(server);
goto out; /* reconnecting is slow */
} else if (server->rstate == SMB_RECV_REQUEST)
smbiod_handle_request(server);
} while (result > 0 && maxwork-- > 0);
/*
* If there is more to read then we want to be sure to wake up again.
*/
if (server->state != CONN_VALID)
goto out;
if (smb_recv_available(server) > 0)
set_bit(SMBIOD_DATA_READY, &smbiod_flags);
do {
result = smb_request_send_server(server);
if (result < 0) {
server->state = CONN_INVALID;
smbiod_retry(server);
goto out; /* reconnecting is slow */
}
} while (result > 0);
/*
* If the last request was not sent out we want to wake up again.
*/
if (!list_empty(&server->xmitq))
set_bit(SMBIOD_DATA_READY, &smbiod_flags);
out:
return;
}
/*
* smbiod kernel thread
*/
static int smbiod(void *unused)
{
VERBOSE("SMB Kernel thread starting (%d) ...\n", current->pid);
for (;;) {
struct smb_sb_info *server;
struct list_head *pos, *n;
/* FIXME: Use poll? */
wait_event_interruptible(smbiod_wait,
test_bit(SMBIOD_DATA_READY, &smbiod_flags));
if (signal_pending(current)) {
spin_lock(&servers_lock);
smbiod_state = SMBIOD_DEAD;
spin_unlock(&servers_lock);
break;
}
clear_bit(SMBIOD_DATA_READY, &smbiod_flags);
spin_lock(&servers_lock);
if (list_empty(&smb_servers)) {
smbiod_state = SMBIOD_DEAD;
spin_unlock(&servers_lock);
break;
}
list_for_each_safe(pos, n, &smb_servers) {
server = list_entry(pos, struct smb_sb_info, entry);
VERBOSE("checking server %p\n", server);
if (server->state == CONN_VALID) {
spin_unlock(&servers_lock);
smb_lock_server(server);
smbiod_doio(server);
smb_unlock_server(server);
spin_lock(&servers_lock);
}
}
spin_unlock(&servers_lock);
}
VERBOSE("SMB Kernel thread exiting (%d) ...\n", current->pid);
module_put_and_exit(0);
}