[PATCH 3/3] ide-floppy: allocate only toplevel packet commands

From: Borislav Petkov
Date: Thu Nov 20 2008 - 00:42:23 EST

Next message: Borislav Petkov: "[PATCH 2/3] ide: make IDE_AFLAG_.. numbering continuous again"
Previous message: Borislav Petkov: "[PATCH 00/03] ide misc leftovers"
In reply to: Borislav Petkov: "[PATCH 1/3] ide-cd: move debug defines into header"
Next in thread: Borislav Petkov: "[PATCH 2/3] ide: make IDE_AFLAG_.. numbering continuous again"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

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@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <petkovbb@xxxxxxxxx>
---
drivers/ide/ide-floppy.c | 26 +++++++++---------
drivers/ide/ide-floppy_ioctl.c | 58 ++++++++++++++++++++-------------------
2 files changed, 43 insertions(+), 41 deletions(-)

diff --git a/drivers/ide/ide-floppy.c b/drivers/ide/ide-floppy.c
index aeb1ad7..1f07f38 100644
--- a/drivers/ide/ide-floppy.c
+++ b/drivers/ide/ide-floppy.c
@@ -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;
}
diff --git a/drivers/ide/ide-floppy_ioctl.c b/drivers/ide/ide-floppy_ioctl.c
index 2bc51ff..8f8be85 100644
--- a/drivers/ide/ide-floppy_ioctl.c
+++ b/drivers/ide/ide-floppy_ioctl.c
@@ -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 @@ out:
* 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;

--
1.6.0.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

Next message: Borislav Petkov: "[PATCH 2/3] ide: make IDE_AFLAG_.. numbering continuous again"
Previous message: Borislav Petkov: "[PATCH 00/03] ide misc leftovers"
In reply to: Borislav Petkov: "[PATCH 1/3] ide-cd: move debug defines into header"
Next in thread: Borislav Petkov: "[PATCH 2/3] ide: make IDE_AFLAG_.. numbering continuous again"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]