[PATCH 07/10] ide-tape: use byte size instead of sectors on rw issue functions

From: Tejun Heo
Date: Wed Mar 25 2009 - 10:20:50 EST


Impact: cleanup

Byte size is what most issue functions deal with, make
idetape_queue_rw_tail() and its wrappers take byte size instead of
sector counts. idetape_chrdev_read() and write() functions are
converted to use tape->buffer_size instead of ctl from tape->cap.

This cleans up code a little bit and will ease the next r/w
reimplementation.

Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
---
drivers/ide/ide-tape.c | 45 ++++++++++++++++++++-------------------------
1 files changed, 20 insertions(+), 25 deletions(-)

diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
index c013954..5fc3282 100644
--- a/drivers/ide/ide-tape.c
+++ b/drivers/ide/ide-tape.c
@@ -879,15 +879,15 @@ static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
* Generate a read/write request for the block device interface and wait for it
* to be serviced.
*/
-static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks)
+static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int size)
{
idetape_tape_t *tape = drive->driver_data;
- size_t size = blocks * tape->blk_size;
struct request *rq;
int ret;

debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd);
BUG_ON(cmd != REQ_IDETAPE_READ && cmd != REQ_IDETAPE_WRITE);
+ BUG_ON(size < 0 || size % tape->blk_size);

rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
rq->cmd_type = REQ_TYPE_SPECIAL;
@@ -954,17 +954,16 @@ static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
}

/* Queue up a character device originated write request. */
-static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks)
+static int idetape_add_chrdev_write_request(ide_drive_t *drive, int size)
{
debug_log(DBG_CHRDEV, "Enter %s\n", __func__);

- return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks);
+ return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, size);
}

static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
- int blocks;

if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
@@ -972,15 +971,10 @@ static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
return;
}
if (tape->buf) {
- blocks = tape->valid / tape->blk_size;
- if (tape->valid % tape->blk_size) {
- blocks++;
- memset(tape->buf + tape->valid, 0,
- tape->blk_size - tape->valid % tape->blk_size);
- }
- (void) idetape_add_chrdev_write_request(drive, blocks);
- }
- if (tape->buf != NULL) {
+ size_t aligned = roundup(tape->valid, tape->blk_size);
+
+ memset(tape->cur + tape->valid, 0, aligned - tape->valid);
+ idetape_add_chrdev_write_request(drive, aligned);
kfree(tape->buf);
tape->buf = NULL;
}
@@ -1034,9 +1028,9 @@ static int idetape_init_rw(ide_drive_t *drive, int dir)
}

/* called from idetape_chrdev_read() to service a chrdev read request. */
-static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks)
+static int idetape_add_chrdev_read_request(ide_drive_t *drive, int size)
{
- debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks);
+ debug_log(DBG_PROCS, "Enter %s, %d bytes\n", __func__, size);

/* If we are at a filemark, return a read length of 0 */
if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags))
@@ -1044,7 +1038,7 @@ static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks)

idetape_init_rw(drive, IDETAPE_DIR_READ);

- return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks);
+ return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, size);
}

static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
@@ -1056,8 +1050,7 @@ static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
while (bcount) {
unsigned int count = min(tape->buffer_size, bcount);

- idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
- count / tape->blk_size);
+ idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, count);
bcount -= count;
}
}
@@ -1189,7 +1182,6 @@ static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
ide_drive_t *drive = tape->drive;
ssize_t bytes_read, temp, actually_read = 0, rc;
ssize_t ret = 0;
- u16 ctl = *(u16 *)&tape->caps[12];

debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);

@@ -1214,7 +1206,8 @@ static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
tape->valid -= actually_read;
}
while (count >= tape->buffer_size) {
- bytes_read = idetape_add_chrdev_read_request(drive, ctl);
+ bytes_read = idetape_add_chrdev_read_request(drive,
+ tape->buffer_size);
if (bytes_read <= 0)
goto finish;
if (copy_to_user(buf, tape->cur, bytes_read))
@@ -1224,7 +1217,8 @@ static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
actually_read += bytes_read;
}
if (count) {
- bytes_read = idetape_add_chrdev_read_request(drive, ctl);
+ bytes_read = idetape_add_chrdev_read_request(drive,
+ tape->buffer_size);
if (bytes_read <= 0)
goto finish;
temp = min((unsigned long)count, (unsigned long)bytes_read);
@@ -1252,7 +1246,6 @@ static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
ide_drive_t *drive = tape->drive;
ssize_t actually_written = 0;
ssize_t ret = 0;
- u16 ctl = *(u16 *)&tape->caps[12];
int rc;

/* The drive is write protected. */
@@ -1280,7 +1273,8 @@ static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,

if (tape->valid == tape->buffer_size) {
ssize_t retval;
- retval = idetape_add_chrdev_write_request(drive, ctl);
+ retval = idetape_add_chrdev_write_request(drive,
+ tape->buffer_size);
if (retval <= 0)
return (retval);
}
@@ -1291,7 +1285,8 @@ static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
ret = -EFAULT;
buf += tape->buffer_size;
count -= tape->buffer_size;
- retval = idetape_add_chrdev_write_request(drive, ctl);
+ retval = idetape_add_chrdev_write_request(drive,
+ tape->buffer_size);
actually_written += tape->buffer_size;
if (retval <= 0)
return (retval);
--
1.6.0.2

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