linux/drivers/scsi/scsi_tgt_if.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  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

400 lines
9.1 KiB
C

/*
* SCSI target kernel/user interface functions
*
* Copyright (C) 2005 FUJITA Tomonori <tomof@acm.org>
* Copyright (C) 2005 Mike Christie <michaelc@cs.wisc.edu>
*
* 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 2 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, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include <linux/miscdevice.h>
#include <linux/gfp.h>
#include <linux/file.h>
#include <linux/smp_lock.h>
#include <net/tcp.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_tgt.h>
#include <scsi/scsi_tgt_if.h>
#include <asm/cacheflush.h>
#include "scsi_tgt_priv.h"
#if TGT_RING_SIZE < PAGE_SIZE
# define TGT_RING_SIZE PAGE_SIZE
#endif
#define TGT_RING_PAGES (TGT_RING_SIZE >> PAGE_SHIFT)
#define TGT_EVENT_PER_PAGE (PAGE_SIZE / sizeof(struct tgt_event))
#define TGT_MAX_EVENTS (TGT_EVENT_PER_PAGE * TGT_RING_PAGES)
struct tgt_ring {
u32 tr_idx;
unsigned long tr_pages[TGT_RING_PAGES];
spinlock_t tr_lock;
};
/* tx_ring : kernel->user, rx_ring : user->kernel */
static struct tgt_ring tx_ring, rx_ring;
static DECLARE_WAIT_QUEUE_HEAD(tgt_poll_wait);
static inline void tgt_ring_idx_inc(struct tgt_ring *ring)
{
if (ring->tr_idx == TGT_MAX_EVENTS - 1)
ring->tr_idx = 0;
else
ring->tr_idx++;
}
static struct tgt_event *tgt_head_event(struct tgt_ring *ring, u32 idx)
{
u32 pidx, off;
pidx = idx / TGT_EVENT_PER_PAGE;
off = idx % TGT_EVENT_PER_PAGE;
return (struct tgt_event *)
(ring->tr_pages[pidx] + sizeof(struct tgt_event) * off);
}
static int tgt_uspace_send_event(u32 type, struct tgt_event *p)
{
struct tgt_event *ev;
struct tgt_ring *ring = &tx_ring;
unsigned long flags;
int err = 0;
spin_lock_irqsave(&ring->tr_lock, flags);
ev = tgt_head_event(ring, ring->tr_idx);
if (!ev->hdr.status)
tgt_ring_idx_inc(ring);
else
err = -BUSY;
spin_unlock_irqrestore(&ring->tr_lock, flags);
if (err)
return err;
memcpy(ev, p, sizeof(*ev));
ev->hdr.type = type;
mb();
ev->hdr.status = 1;
flush_dcache_page(virt_to_page(ev));
wake_up_interruptible(&tgt_poll_wait);
return 0;
}
int scsi_tgt_uspace_send_cmd(struct scsi_cmnd *cmd, u64 itn_id,
struct scsi_lun *lun, u64 tag)
{
struct Scsi_Host *shost = scsi_tgt_cmd_to_host(cmd);
struct tgt_event ev;
int err;
memset(&ev, 0, sizeof(ev));
ev.p.cmd_req.host_no = shost->host_no;
ev.p.cmd_req.itn_id = itn_id;
ev.p.cmd_req.data_len = scsi_bufflen(cmd);
memcpy(ev.p.cmd_req.scb, cmd->cmnd, sizeof(ev.p.cmd_req.scb));
memcpy(ev.p.cmd_req.lun, lun, sizeof(ev.p.cmd_req.lun));
ev.p.cmd_req.attribute = cmd->tag;
ev.p.cmd_req.tag = tag;
dprintk("%p %d %u %x %llx\n", cmd, shost->host_no,
ev.p.cmd_req.data_len, cmd->tag,
(unsigned long long) ev.p.cmd_req.tag);
err = tgt_uspace_send_event(TGT_KEVENT_CMD_REQ, &ev);
if (err)
eprintk("tx buf is full, could not send\n");
return err;
}
int scsi_tgt_uspace_send_status(struct scsi_cmnd *cmd, u64 itn_id, u64 tag)
{
struct Scsi_Host *shost = scsi_tgt_cmd_to_host(cmd);
struct tgt_event ev;
int err;
memset(&ev, 0, sizeof(ev));
ev.p.cmd_done.host_no = shost->host_no;
ev.p.cmd_done.itn_id = itn_id;
ev.p.cmd_done.tag = tag;
ev.p.cmd_done.result = cmd->result;
dprintk("%p %d %llu %u %x\n", cmd, shost->host_no,
(unsigned long long) ev.p.cmd_req.tag,
ev.p.cmd_req.data_len, cmd->tag);
err = tgt_uspace_send_event(TGT_KEVENT_CMD_DONE, &ev);
if (err)
eprintk("tx buf is full, could not send\n");
return err;
}
int scsi_tgt_uspace_send_tsk_mgmt(int host_no, u64 itn_id, int function,
u64 tag, struct scsi_lun *scsilun, void *data)
{
struct tgt_event ev;
int err;
memset(&ev, 0, sizeof(ev));
ev.p.tsk_mgmt_req.host_no = host_no;
ev.p.tsk_mgmt_req.itn_id = itn_id;
ev.p.tsk_mgmt_req.function = function;
ev.p.tsk_mgmt_req.tag = tag;
memcpy(ev.p.tsk_mgmt_req.lun, scsilun, sizeof(ev.p.tsk_mgmt_req.lun));
ev.p.tsk_mgmt_req.mid = (u64) (unsigned long) data;
dprintk("%d %x %llx %llx\n", host_no, function, (unsigned long long) tag,
(unsigned long long) ev.p.tsk_mgmt_req.mid);
err = tgt_uspace_send_event(TGT_KEVENT_TSK_MGMT_REQ, &ev);
if (err)
eprintk("tx buf is full, could not send\n");
return err;
}
int scsi_tgt_uspace_send_it_nexus_request(int host_no, u64 itn_id,
int function, char *initiator_id)
{
struct tgt_event ev;
int err;
memset(&ev, 0, sizeof(ev));
ev.p.it_nexus_req.host_no = host_no;
ev.p.it_nexus_req.function = function;
ev.p.it_nexus_req.itn_id = itn_id;
if (initiator_id)
strncpy(ev.p.it_nexus_req.initiator_id, initiator_id,
sizeof(ev.p.it_nexus_req.initiator_id));
dprintk("%d %x %llx\n", host_no, function, (unsigned long long)itn_id);
err = tgt_uspace_send_event(TGT_KEVENT_IT_NEXUS_REQ, &ev);
if (err)
eprintk("tx buf is full, could not send\n");
return err;
}
static int event_recv_msg(struct tgt_event *ev)
{
int err = 0;
switch (ev->hdr.type) {
case TGT_UEVENT_CMD_RSP:
err = scsi_tgt_kspace_exec(ev->p.cmd_rsp.host_no,
ev->p.cmd_rsp.itn_id,
ev->p.cmd_rsp.result,
ev->p.cmd_rsp.tag,
ev->p.cmd_rsp.uaddr,
ev->p.cmd_rsp.len,
ev->p.cmd_rsp.sense_uaddr,
ev->p.cmd_rsp.sense_len,
ev->p.cmd_rsp.rw);
break;
case TGT_UEVENT_TSK_MGMT_RSP:
err = scsi_tgt_kspace_tsk_mgmt(ev->p.tsk_mgmt_rsp.host_no,
ev->p.tsk_mgmt_rsp.itn_id,
ev->p.tsk_mgmt_rsp.mid,
ev->p.tsk_mgmt_rsp.result);
break;
case TGT_UEVENT_IT_NEXUS_RSP:
err = scsi_tgt_kspace_it_nexus_rsp(ev->p.it_nexus_rsp.host_no,
ev->p.it_nexus_rsp.itn_id,
ev->p.it_nexus_rsp.result);
break;
default:
eprintk("unknown type %d\n", ev->hdr.type);
err = -EINVAL;
}
return err;
}
static ssize_t tgt_write(struct file *file, const char __user * buffer,
size_t count, loff_t * ppos)
{
struct tgt_event *ev;
struct tgt_ring *ring = &rx_ring;
while (1) {
ev = tgt_head_event(ring, ring->tr_idx);
/* do we need this? */
flush_dcache_page(virt_to_page(ev));
if (!ev->hdr.status)
break;
tgt_ring_idx_inc(ring);
event_recv_msg(ev);
ev->hdr.status = 0;
};
return count;
}
static unsigned int tgt_poll(struct file * file, struct poll_table_struct *wait)
{
struct tgt_event *ev;
struct tgt_ring *ring = &tx_ring;
unsigned long flags;
unsigned int mask = 0;
u32 idx;
poll_wait(file, &tgt_poll_wait, wait);
spin_lock_irqsave(&ring->tr_lock, flags);
idx = ring->tr_idx ? ring->tr_idx - 1 : TGT_MAX_EVENTS - 1;
ev = tgt_head_event(ring, idx);
if (ev->hdr.status)
mask |= POLLIN | POLLRDNORM;
spin_unlock_irqrestore(&ring->tr_lock, flags);
return mask;
}
static int uspace_ring_map(struct vm_area_struct *vma, unsigned long addr,
struct tgt_ring *ring)
{
int i, err;
for (i = 0; i < TGT_RING_PAGES; i++) {
struct page *page = virt_to_page(ring->tr_pages[i]);
err = vm_insert_page(vma, addr, page);
if (err)
return err;
addr += PAGE_SIZE;
}
return 0;
}
static int tgt_mmap(struct file *filp, struct vm_area_struct *vma)
{
unsigned long addr;
int err;
if (vma->vm_pgoff)
return -EINVAL;
if (vma->vm_end - vma->vm_start != TGT_RING_SIZE * 2) {
eprintk("mmap size must be %lu, not %lu \n",
TGT_RING_SIZE * 2, vma->vm_end - vma->vm_start);
return -EINVAL;
}
addr = vma->vm_start;
err = uspace_ring_map(vma, addr, &tx_ring);
if (err)
return err;
err = uspace_ring_map(vma, addr + TGT_RING_SIZE, &rx_ring);
return err;
}
static int tgt_open(struct inode *inode, struct file *file)
{
tx_ring.tr_idx = rx_ring.tr_idx = 0;
cycle_kernel_lock();
return 0;
}
static const struct file_operations tgt_fops = {
.owner = THIS_MODULE,
.open = tgt_open,
.poll = tgt_poll,
.write = tgt_write,
.mmap = tgt_mmap,
};
static struct miscdevice tgt_miscdev = {
.minor = MISC_DYNAMIC_MINOR,
.name = "tgt",
.fops = &tgt_fops,
};
static void tgt_ring_exit(struct tgt_ring *ring)
{
int i;
for (i = 0; i < TGT_RING_PAGES; i++)
free_page(ring->tr_pages[i]);
}
static int tgt_ring_init(struct tgt_ring *ring)
{
int i;
spin_lock_init(&ring->tr_lock);
for (i = 0; i < TGT_RING_PAGES; i++) {
ring->tr_pages[i] = get_zeroed_page(GFP_KERNEL);
if (!ring->tr_pages[i]) {
eprintk("out of memory\n");
return -ENOMEM;
}
}
return 0;
}
void scsi_tgt_if_exit(void)
{
tgt_ring_exit(&tx_ring);
tgt_ring_exit(&rx_ring);
misc_deregister(&tgt_miscdev);
}
int scsi_tgt_if_init(void)
{
int err;
err = tgt_ring_init(&tx_ring);
if (err)
return err;
err = tgt_ring_init(&rx_ring);
if (err)
goto free_tx_ring;
err = misc_register(&tgt_miscdev);
if (err)
goto free_rx_ring;
return 0;
free_rx_ring:
tgt_ring_exit(&rx_ring);
free_tx_ring:
tgt_ring_exit(&tx_ring);
return err;
}