From: Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx> Subject: [PATCH] ide: allow ide_dev_read_id() to be called from the IRQ context * Un-static __ide_wait_stat(). * Allow ide_dev_read_id() helper to be called from the IRQ context by adding irq_ctx flag and using mdelay()/__ide_wait_stat() when needed. * Switch ide_driveid_update() to set irq_ctx flag. This change is needed for the consecutive patch which fixes races in handling of user-space SET XFER commands but for improved bisectability and clarity it is better to do it in a separate patch. Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@xxxxxxxxx> --- I'm not completely happy with this version of patch since I originally intended to unify ide_busy_sleep() with __ide_wait_stat() first.. drivers/ide/ide-iops.c | 6 +++--- drivers/ide/ide-probe.c | 31 +++++++++++++++++++++---------- include/linux/ide.h | 3 ++- 3 files changed, 26 insertions(+), 14 deletions(-) Index: b/drivers/ide/ide-iops.c =================================================================== --- a/drivers/ide/ide-iops.c +++ b/drivers/ide/ide-iops.c @@ -102,8 +102,8 @@ EXPORT_SYMBOL(ide_fixstring); * setting a timer to wake up at half second intervals thereafter, * until timeout is achieved, before timing out. */ -static int __ide_wait_stat(ide_drive_t *drive, u8 good, u8 bad, - unsigned long timeout, u8 *rstat) +int __ide_wait_stat(ide_drive_t *drive, u8 good, u8 bad, + unsigned long timeout, u8 *rstat) { ide_hwif_t *hwif = drive->hwif; const struct ide_tp_ops *tp_ops = hwif->tp_ops; @@ -316,7 +316,7 @@ int ide_driveid_update(ide_drive_t *driv return 0; SELECT_MASK(drive, 1); - rc = ide_dev_read_id(drive, ATA_CMD_ID_ATA, id); + rc = ide_dev_read_id(drive, ATA_CMD_ID_ATA, id, 1); SELECT_MASK(drive, 0); if (rc) Index: b/drivers/ide/ide-probe.c =================================================================== --- a/drivers/ide/ide-probe.c +++ b/drivers/ide/ide-probe.c @@ -238,6 +238,7 @@ static void do_identify(ide_drive_t *dri * @drive: drive to identify * @cmd: command to use * @id: buffer for IDENTIFY data + * @irq_ctx: flag set when called from the IRQ context * * Sends an ATA(PI) IDENTIFY request to a drive and waits for a response. * @@ -246,7 +247,7 @@ static void do_identify(ide_drive_t *dri * 2 device aborted the command (refused to identify itself) */ -int ide_dev_read_id(ide_drive_t *drive, u8 cmd, u16 *id) +int ide_dev_read_id(ide_drive_t *drive, u8 cmd, u16 *id, int irq_ctx) { ide_hwif_t *hwif = drive->hwif; struct ide_io_ports *io_ports = &hwif->io_ports; @@ -263,7 +264,10 @@ int ide_dev_read_id(ide_drive_t *drive, tp_ops->write_devctl(hwif, ATA_NIEN | ATA_DEVCTL_OBS); /* take a deep breath */ - msleep(50); + if (irq_ctx) + mdelay(50); + else + msleep(50); if (io_ports->ctl_addr && (hwif->host_flags & IDE_HFLAG_BROKEN_ALTSTATUS) == 0) { @@ -295,12 +299,19 @@ int ide_dev_read_id(ide_drive_t *drive, timeout = ((cmd == ATA_CMD_ID_ATA) ? WAIT_WORSTCASE : WAIT_PIDENTIFY) / 2; - if (ide_busy_sleep(drive, timeout, use_altstatus)) - return 1; - /* wait for IRQ and ATA_DRQ */ - msleep(50); - s = tp_ops->read_status(hwif); + if (irq_ctx) { + rc = __ide_wait_stat(drive, ATA_DRQ, BAD_R_STAT, timeout, &s); + if (rc) + return 1; + } else { + rc = ide_busy_sleep(drive, timeout, use_altstatus); + if (rc) + return 1; + + msleep(50); + s = tp_ops->read_status(hwif); + } if (OK_STAT(s, ATA_DRQ, BAD_R_STAT)) { /* drive returned ID */ @@ -406,10 +417,10 @@ static int do_probe (ide_drive_t *drive, if (OK_STAT(stat, ATA_DRDY, ATA_BUSY) || present || cmd == ATA_CMD_ID_ATAPI) { - rc = ide_dev_read_id(drive, cmd, id); + rc = ide_dev_read_id(drive, cmd, id, 0); if (rc) /* failed: try again */ - rc = ide_dev_read_id(drive, cmd, id); + rc = ide_dev_read_id(drive, cmd, id, 0); stat = tp_ops->read_status(hwif); @@ -424,7 +435,7 @@ static int do_probe (ide_drive_t *drive, msleep(50); tp_ops->exec_command(hwif, ATA_CMD_DEV_RESET); (void)ide_busy_sleep(drive, WAIT_WORSTCASE, 0); - rc = ide_dev_read_id(drive, cmd, id); + rc = ide_dev_read_id(drive, cmd, id, 0); } /* ensure drive IRQ is clear */ Index: b/include/linux/ide.h =================================================================== --- a/include/linux/ide.h +++ b/include/linux/ide.h @@ -1081,6 +1081,7 @@ extern void ide_fixstring(u8 *, const in int ide_busy_sleep(ide_drive_t *, unsigned long, int); +int __ide_wait_stat(ide_drive_t *, u8, u8, unsigned long, u8 *); int ide_wait_stat(ide_startstop_t *, ide_drive_t *, u8, u8, unsigned long); ide_startstop_t ide_do_park_unpark(ide_drive_t *, struct request *); @@ -1169,7 +1170,7 @@ int ide_no_data_taskfile(ide_drive_t *, int ide_taskfile_ioctl(ide_drive_t *, unsigned long); -int ide_dev_read_id(ide_drive_t *, u8, u16 *); +int ide_dev_read_id(ide_drive_t *, u8, u16 *, int); extern int ide_driveid_update(ide_drive_t *); extern int ide_config_drive_speed(ide_drive_t *, u8); -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html