ide-tape: use byte size instead of sectors on rw issue functions
authorTejun Heo <tj@kernel.org>
Sat, 18 Apr 2009 23:46:03 +0000 (08:46 +0900)
committerJens Axboe <jens.axboe@oracle.com>
Tue, 28 Apr 2009 05:37:32 +0000 (07:37 +0200)
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@kernel.org>
drivers/ide/ide-tape.c

index 4da7fa9bca1eaa5b58b4578afbd7e0767d521ed1..d5e9bb286e306b990d2992db13439f2895a7d3f0 100644 (file)
@@ -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, 0, aligned - tape->valid);
+               idetape_add_chrdev_write_request(drive, aligned);
                kfree(tape->buf);
                tape->buf = NULL;
        }
@@ -1038,9 +1032,9 @@ 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))
@@ -1048,7 +1042,7 @@ 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)
@@ -1060,8 +1054,7 @@ 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;
        }
 }
@@ -1193,7 +1186,6 @@ 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);
 
@@ -1218,7 +1210,8 @@ 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))
@@ -1228,7 +1221,8 @@ 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);
@@ -1256,7 +1250,6 @@ 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. */
@@ -1284,7 +1277,8 @@ 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);
                }
@@ -1295,7 +1289,8 @@ 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);