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ide-floppy: allocate only toplevel packet commands
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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: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
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Linus Torvalds authored and Bartlomiej Zolnierkiewicz committed Jan 2, 2009
1 parent bf64741 commit 07bd3f4
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Showing 2 changed files with 43 additions and 41 deletions.
26 changes: 13 additions & 13 deletions drivers/ide/ide-floppy.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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;

Expand Down Expand Up @@ -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;
}
Expand Down
58 changes: 30 additions & 28 deletions drivers/ide/ide-floppy_ioctl.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand All @@ -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;
Expand All @@ -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;
Expand Down Expand Up @@ -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) {
Expand Down Expand Up @@ -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:
Expand All @@ -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 &&
Expand Down Expand Up @@ -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;
}
Expand All @@ -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;

Expand Down

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