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| author | Tejun Heo <htejun@gmail.com> | 2008-01-26 20:13:10 +0100 |
|---|---|---|
| committer | Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> | 2008-01-26 20:13:10 +0100 |
| commit | 35cf2b94d0ecb7034cfa05dd725721538bbb83fc (patch) | |
| tree | 6c3681f06b078626aeeb8de1e28bbdd458f95c70 | |
| parent | 63c4467805c9b23231d8bc9b61305b2013f9fea2 (diff) | |
| download | kernel_samsung_smdk4412-35cf2b94d0ecb7034cfa05dd725721538bbb83fc.zip kernel_samsung_smdk4412-35cf2b94d0ecb7034cfa05dd725721538bbb83fc.tar.gz kernel_samsung_smdk4412-35cf2b94d0ecb7034cfa05dd725721538bbb83fc.tar.bz2 | |
ide: fix ->io_32bit race in ide_taskfile_ioctl()
In ide_taskfile_ioctl(), there was a race condition involving
drive->io_32bit. It was cleared and restored during ioctl
requests but there was no synchronization with other requests.
So, other requests could execute with the altered ->io_32bit
setting or updated drive->io_32bit could be overwritten by
ide_taskfile_ioctl().
This patch adds IDE_TFLAG_IO_16BIT flag to indicate to
ide_pio_datablock() that 16-bit I/O is needed regardless of
drive->io_32bit settting.
Bart:
- ported it over recent IDE changes
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
| -rw-r--r-- | drivers/ide/ide-taskfile.c | 17 | ||||
| -rw-r--r-- | include/linux/ide.h | 2 |
2 files changed, 14 insertions, 5 deletions
diff --git a/drivers/ide/ide-taskfile.c b/drivers/ide/ide-taskfile.c index 3ecafab..b72a9ae 100644 --- a/drivers/ide/ide-taskfile.c +++ b/drivers/ide/ide-taskfile.c @@ -346,9 +346,18 @@ static void ide_pio_multi(ide_drive_t *drive, unsigned int write) static void ide_pio_datablock(ide_drive_t *drive, struct request *rq, unsigned int write) { + u8 saved_io_32bit = drive->io_32bit; + if (rq->bio) /* fs request */ rq->errors = 0; + if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { + ide_task_t *task = rq->special; + + if (task->tf_flags & IDE_TFLAG_IO_16BIT) + drive->io_32bit = 0; + } + touch_softlockup_watchdog(); switch (drive->hwif->data_phase) { @@ -360,6 +369,8 @@ static void ide_pio_datablock(ide_drive_t *drive, struct request *rq, ide_pio_sector(drive, write); break; } + + drive->io_32bit = saved_io_32bit; } static ide_startstop_t task_error(ide_drive_t *drive, struct request *rq, @@ -555,7 +566,6 @@ int ide_taskfile_ioctl (ide_drive_t *drive, unsigned int cmd, unsigned long arg) unsigned int taskin = 0; unsigned int taskout = 0; u16 nsect = 0; - u8 io_32bit = drive->io_32bit; char __user *buf = (char __user *)arg; // printk("IDE Taskfile ...\n"); @@ -608,7 +618,7 @@ int ide_taskfile_ioctl (ide_drive_t *drive, unsigned int cmd, unsigned long arg) args.data_phase = req_task->data_phase; - args.tf_flags = IDE_TFLAG_OUT_DEVICE; + args.tf_flags = IDE_TFLAG_IO_16BIT | IDE_TFLAG_OUT_DEVICE; if (drive->addressing == 1) args.tf_flags |= IDE_TFLAG_LBA48; @@ -646,7 +656,6 @@ int ide_taskfile_ioctl (ide_drive_t *drive, unsigned int cmd, unsigned long arg) if (req_task->in_flags.b.data) args.tf_flags |= IDE_TFLAG_IN_DATA; - drive->io_32bit = 0; switch(req_task->data_phase) { case TASKFILE_MULTI_OUT: if (!drive->mult_count) { @@ -742,8 +751,6 @@ abort: // printk("IDE Taskfile ioctl ended. rc = %i\n", err); - drive->io_32bit = io_32bit; - return err; } #endif diff --git a/include/linux/ide.h b/include/linux/ide.h index f94cf03..c1a8b8b 100644 --- a/include/linux/ide.h +++ b/include/linux/ide.h @@ -931,6 +931,8 @@ enum { IDE_TFLAG_IN_TF = IDE_TFLAG_IN_NSECT | IDE_TFLAG_IN_LBA, IDE_TFLAG_IN_DEVICE = (1 << 29), + /* force 16-bit I/O operations */ + IDE_TFLAG_IO_16BIT = (1 << 30), }; struct ide_taskfile { |