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Commit 07bd3f47 authored by Linus Torvalds's avatar Linus Torvalds Committed by Bartlomiej Zolnierkiewicz
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ide-floppy: allocate only toplevel packet commands 



This makes the top-level function just allocate a single pc entry, and then
pass it down as a pointer to all the helper functions that also need one
of those "struct ide_atapi_pc" things. As far as I can tell, the use of
these things never overlaps each other, BUT I DID NOT CHECK VERY CLOSELY!

So I'm not guaranteeing this is correct, and I don't have the hardware. It
would be good for somebody who knows the code more, and has the hardware,
could please test this?

With this, ide-floppy still has fairly big stack usage, but instead of

	idefloppy_ioctl [vmlinux]:              1208
	ide_floppy_get_capacity [vmlinux]:      872
	idefloppy_release [vmlinux]:            408
	idefloppy_open [vmlinux]:               408

where those two first ones are at the very top of the list of stack users
for me, it's now

	ide_floppy_get_capacity [vmlinux]:           404
	ide_floppy_ioctl [vmlinux]:                  364

ie they are still high, but they are no longer at the top.

Borislav: Since ide_floppy_get_capacity is passed as a function pointer to other
parts of the kernel (e.g., block layer) we need that ide_atapi_pc to be created
on stack. Also, redid stack users numbers above. The two functions missing from
Linus' original 'make stackusage' output are due to ide being
rewritten/reorganized atm.

Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarBorislav Petkov <petkovbb@gmail.com>
Signed-off-by: default avatarBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
parent bf64741f

drivers/ide/ide-floppy.c

+13 −13
Original line number Diff line number Diff line
@@ -342,38 +342,38 @@ static ide_startstop_t ide_floppy_do_request(ide_drive_t *drive, 
 * Look at the flexible disk page parameters. We ignore the CHS capacity

 * parameters and use the LBA parameters instead.

 */

static int ide_floppy_get_flexible_disk_page(ide_drive_t *drive)

static int ide_floppy_get_flexible_disk_page(ide_drive_t *drive,

					     struct ide_atapi_pc *pc)

{

	struct ide_disk_obj *floppy = drive->driver_data;

	struct gendisk *disk = floppy->disk;

	struct ide_atapi_pc pc;

	u8 *page;

	int capacity, lba_capacity;

	u16 transfer_rate, sector_size, cyls, rpm;

	u8 heads, sectors;



	ide_floppy_create_mode_sense_cmd(&pc, IDEFLOPPY_FLEXIBLE_DISK_PAGE);

	ide_floppy_create_mode_sense_cmd(pc, IDEFLOPPY_FLEXIBLE_DISK_PAGE);



	if (ide_queue_pc_tail(drive, disk, &pc)) {

	if (ide_queue_pc_tail(drive, disk, pc)) {

		printk(KERN_ERR PFX "Can't get flexible disk page params\n");

		return 1;

	}



	if (pc.buf[3] & 0x80)

	if (pc->buf[3] & 0x80)

		drive->dev_flags |= IDE_DFLAG_WP;

	else

		drive->dev_flags &= ~IDE_DFLAG_WP;



	set_disk_ro(disk, !!(drive->dev_flags & IDE_DFLAG_WP));



	page = &pc.buf[8];

	page = &pc->buf[8];



	transfer_rate = be16_to_cpup((__be16 *)&pc.buf[8 + 2]);

	sector_size   = be16_to_cpup((__be16 *)&pc.buf[8 + 6]);

	cyls          = be16_to_cpup((__be16 *)&pc.buf[8 + 8]);

	rpm           = be16_to_cpup((__be16 *)&pc.buf[8 + 28]);

	heads         = pc.buf[8 + 4];

	sectors       = pc.buf[8 + 5];

	transfer_rate = be16_to_cpup((__be16 *)&pc->buf[8 + 2]);

	sector_size   = be16_to_cpup((__be16 *)&pc->buf[8 + 6]);

	cyls          = be16_to_cpup((__be16 *)&pc->buf[8 + 8]);

	rpm           = be16_to_cpup((__be16 *)&pc->buf[8 + 28]);

	heads         = pc->buf[8 + 4];

	sectors       = pc->buf[8 + 5];



	capacity = cyls * heads * sectors * sector_size;
@@ -499,7 +499,7 @@ static int ide_floppy_get_capacity(ide_drive_t *drive) 


	/* Clik! disk does not support get_flexible_disk_page */

	if (!(drive->atapi_flags & IDE_AFLAG_CLIK_DRIVE))

		(void) ide_floppy_get_flexible_disk_page(drive);

		(void) ide_floppy_get_flexible_disk_page(drive, &pc);



	return rc;

}

drivers/ide/ide-floppy_ioctl.c

+30 −28
Original line number Diff line number Diff line
@@ -31,10 +31,11 @@ 
 * On exit we set nformats to the number of records we've actually initialized.

 */



static int ide_floppy_get_format_capacities(ide_drive_t *drive, int __user *arg)

static int ide_floppy_get_format_capacities(ide_drive_t *drive,

					    struct ide_atapi_pc *pc,

					    int __user *arg)

{

	struct ide_disk_obj *floppy = drive->driver_data;

	struct ide_atapi_pc pc;

	u8 header_len, desc_cnt;

	int i, blocks, length, u_array_size, u_index;

	int __user *argp;
@@ -45,13 +46,13 @@ static int ide_floppy_get_format_capacities(ide_drive_t *drive, int __user *arg) 
	if (u_array_size <= 0)

		return -EINVAL;



	ide_floppy_create_read_capacity_cmd(&pc);

	if (ide_queue_pc_tail(drive, floppy->disk, &pc)) {

	ide_floppy_create_read_capacity_cmd(pc);

	if (ide_queue_pc_tail(drive, floppy->disk, pc)) {

		printk(KERN_ERR "ide-floppy: Can't get floppy parameters\n");

		return -EIO;

	}



	header_len = pc.buf[3];

	header_len = pc->buf[3];

	desc_cnt = header_len / 8; /* capacity descriptor of 8 bytes */



	u_index = 0;
@@ -68,8 +69,8 @@ static int ide_floppy_get_format_capacities(ide_drive_t *drive, int __user *arg) 
		if (u_index >= u_array_size)

			break;	/* User-supplied buffer too small */



		blocks = be32_to_cpup((__be32 *)&pc.buf[desc_start]);

		length = be16_to_cpup((__be16 *)&pc.buf[desc_start + 6]);

		blocks = be32_to_cpup((__be32 *)&pc->buf[desc_start]);

		length = be16_to_cpup((__be16 *)&pc->buf[desc_start + 6]);



		if (put_user(blocks, argp))

			return -EFAULT;
@@ -111,29 +112,28 @@ static void ide_floppy_create_format_unit_cmd(struct ide_atapi_pc *pc, int b, 
	pc->flags |= PC_FLAG_WRITING;

}



static int ide_floppy_get_sfrp_bit(ide_drive_t *drive)

static int ide_floppy_get_sfrp_bit(ide_drive_t *drive, struct ide_atapi_pc *pc)

{

	struct ide_disk_obj *floppy = drive->driver_data;

	struct ide_atapi_pc pc;



	drive->atapi_flags &= ~IDE_AFLAG_SRFP;



	ide_floppy_create_mode_sense_cmd(&pc, IDEFLOPPY_CAPABILITIES_PAGE);

	pc.flags |= PC_FLAG_SUPPRESS_ERROR;

	ide_floppy_create_mode_sense_cmd(pc, IDEFLOPPY_CAPABILITIES_PAGE);

	pc->flags |= PC_FLAG_SUPPRESS_ERROR;



	if (ide_queue_pc_tail(drive, floppy->disk, &pc))

	if (ide_queue_pc_tail(drive, floppy->disk, pc))

		return 1;



	if (pc.buf[8 + 2] & 0x40)

	if (pc->buf[8 + 2] & 0x40)

		drive->atapi_flags |= IDE_AFLAG_SRFP;



	return 0;

}



static int ide_floppy_format_unit(ide_drive_t *drive, int __user *arg)

static int ide_floppy_format_unit(ide_drive_t *drive, struct ide_atapi_pc *pc,

				  int __user *arg)

{

	struct ide_disk_obj *floppy = drive->driver_data;

	struct ide_atapi_pc pc;

	int blocks, length, flags, err = 0;



	if (floppy->openers > 1) {
@@ -166,10 +166,10 @@ static int ide_floppy_format_unit(ide_drive_t *drive, int __user *arg) 
		goto out;

	}



	(void)ide_floppy_get_sfrp_bit(drive);

	ide_floppy_create_format_unit_cmd(&pc, blocks, length, flags);

	ide_floppy_get_sfrp_bit(drive, pc);

	ide_floppy_create_format_unit_cmd(pc, blocks, length, flags);



	if (ide_queue_pc_tail(drive, floppy->disk, &pc))

	if (ide_queue_pc_tail(drive, floppy->disk, pc))

		err = -EIO;



out:
@@ -188,15 +188,16 @@ static int ide_floppy_format_unit(ide_drive_t *drive, int __user *arg) 
 * the dsc bit, and return either 0 or 65536.

 */



static int ide_floppy_get_format_progress(ide_drive_t *drive, int __user *arg)

static int ide_floppy_get_format_progress(ide_drive_t *drive,

					  struct ide_atapi_pc *pc,

					  int __user *arg)

{

	struct ide_disk_obj *floppy = drive->driver_data;

	struct ide_atapi_pc pc;

	int progress_indication = 0x10000;



	if (drive->atapi_flags & IDE_AFLAG_SRFP) {

		ide_create_request_sense_cmd(drive, &pc);

		if (ide_queue_pc_tail(drive, floppy->disk, &pc))

		ide_create_request_sense_cmd(drive, pc);

		if (ide_queue_pc_tail(drive, floppy->disk, pc))

			return -EIO;



		if (floppy->sense_key == 2 &&
@@ -241,20 +242,21 @@ static int ide_floppy_lockdoor(ide_drive_t *drive, struct ide_atapi_pc *pc, 
	return 0;

}



static int ide_floppy_format_ioctl(ide_drive_t *drive, fmode_t mode,

				   unsigned int cmd, void __user *argp)

static int ide_floppy_format_ioctl(ide_drive_t *drive, struct ide_atapi_pc *pc,

				   fmode_t mode, unsigned int cmd,

				   void __user *argp)

{

	switch (cmd) {

	case IDEFLOPPY_IOCTL_FORMAT_SUPPORTED:

		return 0;

	case IDEFLOPPY_IOCTL_FORMAT_GET_CAPACITY:

		return ide_floppy_get_format_capacities(drive, argp);

		return ide_floppy_get_format_capacities(drive, pc, argp);

	case IDEFLOPPY_IOCTL_FORMAT_START:

		if (!(mode & FMODE_WRITE))

			return -EPERM;

		return ide_floppy_format_unit(drive, (int __user *)argp);

		return ide_floppy_format_unit(drive, pc, (int __user *)argp);

	case IDEFLOPPY_IOCTL_FORMAT_GET_PROGRESS:

		return ide_floppy_get_format_progress(drive, argp);

		return ide_floppy_get_format_progress(drive, pc, argp);

	default:

		return -ENOTTY;

	}
@@ -270,7 +272,7 @@ int ide_floppy_ioctl(ide_drive_t *drive, struct block_device *bdev, 
	if (cmd == CDROMEJECT || cmd == CDROM_LOCKDOOR)

		return ide_floppy_lockdoor(drive, &pc, arg, cmd);



	err = ide_floppy_format_ioctl(drive, mode, cmd, argp);

	err = ide_floppy_format_ioctl(drive, &pc, mode, cmd, argp);

	if (err != -ENOTTY)

		return err;