linux-stable/drivers/ide/ide-park.c
Mel Gorman 71baba4b92 mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM
__GFP_WAIT was used to signal that the caller was in atomic context and
could not sleep.  Now it is possible to distinguish between true atomic
context and callers that are not willing to sleep.  The latter should
clear __GFP_DIRECT_RECLAIM so kswapd will still wake.  As clearing
__GFP_WAIT behaves differently, there is a risk that people will clear the
wrong flags.  This patch renames __GFP_WAIT to __GFP_RECLAIM to clearly
indicate what it does -- setting it allows all reclaim activity, clearing
them prevents it.

[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00

151 lines
3.5 KiB
C

#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/ide.h>
#include <linux/jiffies.h>
#include <linux/blkdev.h>
DECLARE_WAIT_QUEUE_HEAD(ide_park_wq);
static void issue_park_cmd(ide_drive_t *drive, unsigned long timeout)
{
ide_hwif_t *hwif = drive->hwif;
struct request_queue *q = drive->queue;
struct request *rq;
int rc;
timeout += jiffies;
spin_lock_irq(&hwif->lock);
if (drive->dev_flags & IDE_DFLAG_PARKED) {
int reset_timer = time_before(timeout, drive->sleep);
int start_queue = 0;
drive->sleep = timeout;
wake_up_all(&ide_park_wq);
if (reset_timer && del_timer(&hwif->timer))
start_queue = 1;
spin_unlock_irq(&hwif->lock);
if (start_queue)
blk_run_queue(q);
return;
}
spin_unlock_irq(&hwif->lock);
rq = blk_get_request(q, READ, __GFP_RECLAIM);
rq->cmd[0] = REQ_PARK_HEADS;
rq->cmd_len = 1;
rq->cmd_type = REQ_TYPE_DRV_PRIV;
rq->special = &timeout;
rc = blk_execute_rq(q, NULL, rq, 1);
blk_put_request(rq);
if (rc)
goto out;
/*
* Make sure that *some* command is sent to the drive after the
* timeout has expired, so power management will be reenabled.
*/
rq = blk_get_request(q, READ, GFP_NOWAIT);
if (IS_ERR(rq))
goto out;
rq->cmd[0] = REQ_UNPARK_HEADS;
rq->cmd_len = 1;
rq->cmd_type = REQ_TYPE_DRV_PRIV;
elv_add_request(q, rq, ELEVATOR_INSERT_FRONT);
out:
return;
}
ide_startstop_t ide_do_park_unpark(ide_drive_t *drive, struct request *rq)
{
struct ide_cmd cmd;
struct ide_taskfile *tf = &cmd.tf;
memset(&cmd, 0, sizeof(cmd));
if (rq->cmd[0] == REQ_PARK_HEADS) {
drive->sleep = *(unsigned long *)rq->special;
drive->dev_flags |= IDE_DFLAG_SLEEPING;
tf->command = ATA_CMD_IDLEIMMEDIATE;
tf->feature = 0x44;
tf->lbal = 0x4c;
tf->lbam = 0x4e;
tf->lbah = 0x55;
cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
cmd.valid.in.tf = IDE_VALID_IN_TF | IDE_VALID_DEVICE;
} else /* cmd == REQ_UNPARK_HEADS */
tf->command = ATA_CMD_CHK_POWER;
cmd.tf_flags |= IDE_TFLAG_CUSTOM_HANDLER;
cmd.protocol = ATA_PROT_NODATA;
cmd.rq = rq;
return do_rw_taskfile(drive, &cmd);
}
ssize_t ide_park_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
ide_drive_t *drive = to_ide_device(dev);
ide_hwif_t *hwif = drive->hwif;
unsigned long now;
unsigned int msecs;
if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
return -EOPNOTSUPP;
spin_lock_irq(&hwif->lock);
now = jiffies;
if (drive->dev_flags & IDE_DFLAG_PARKED &&
time_after(drive->sleep, now))
msecs = jiffies_to_msecs(drive->sleep - now);
else
msecs = 0;
spin_unlock_irq(&hwif->lock);
return snprintf(buf, 20, "%u\n", msecs);
}
ssize_t ide_park_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t len)
{
#define MAX_PARK_TIMEOUT 30000
ide_drive_t *drive = to_ide_device(dev);
long int input;
int rc;
rc = kstrtol(buf, 10, &input);
if (rc)
return rc;
if (input < -2)
return -EINVAL;
if (input > MAX_PARK_TIMEOUT) {
input = MAX_PARK_TIMEOUT;
rc = -EOVERFLOW;
}
mutex_lock(&ide_setting_mtx);
if (input >= 0) {
if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
rc = -EOPNOTSUPP;
else if (input || drive->dev_flags & IDE_DFLAG_PARKED)
issue_park_cmd(drive, msecs_to_jiffies(input));
} else {
if (drive->media == ide_disk)
switch (input) {
case -1:
drive->dev_flags &= ~IDE_DFLAG_NO_UNLOAD;
break;
case -2:
drive->dev_flags |= IDE_DFLAG_NO_UNLOAD;
break;
}
else
rc = -EOPNOTSUPP;
}
mutex_unlock(&ide_setting_mtx);
return rc ? rc : len;
}