ide: add support for arbitrary transfer lengths to ide_pio_bytes()

Add support for arbitrary transfer lengths to ide_pio_bytes()
and then inline ide_pio_multi() into ide_pio_datablock().

There should be no functional changes caused by this patch.

Cc: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

diff --git a/drivers/ide/ide-taskfile.c b/drivers/ide/ide-taskfile.c
index 84532be97c006081aa5f1fea3ca85562e8b6f1f6..8d7e87d04b3b550e5327d037c0c6e0f54d2d96a2 100644 (file)
--- a/drivers/ide/ide-taskfile.c
+++ b/drivers/ide/ide-taskfile.c
@@ -189,7 +189,7 @@ static u8 wait_drive_not_busy(ide_drive_t *drive)
 }
 
 static void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd,
-                         unsigned int write, unsigned int nr_bytes)
+                         unsigned int write, unsigned int len)
 {
        ide_hwif_t *hwif = drive->hwif;
        struct scatterlist *sg = hwif->sg_table;
@@ -202,56 +202,55 @@ static void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd,
        u8 *buf;
 
        cursg = cmd->cursg;
-       if (!cursg) {
-               cursg = sg;
-               cmd->cursg = sg;
-       }
+       if (cursg == NULL)
+               cursg = cmd->cursg = sg;
+
+       while (len) {
+               unsigned nr_bytes = min(len, cursg->length - cmd->cursg_ofs);
 
-       page = sg_page(cursg);
-       offset = cursg->offset + cmd->cursg_ofs;
+               if (nr_bytes > PAGE_SIZE)
+                       nr_bytes = PAGE_SIZE;
 
-       /* get the current page and offset */
-       page = nth_page(page, (offset >> PAGE_SHIFT));
-       offset %= PAGE_SIZE;
+               page = sg_page(cursg);
+               offset = cursg->offset + cmd->cursg_ofs;
+
+               /* get the current page and offset */
+               page = nth_page(page, (offset >> PAGE_SHIFT));
+               offset %= PAGE_SIZE;
 
 #ifdef CONFIG_HIGHMEM
-       local_irq_save(flags);
+               local_irq_save(flags);
 #endif
-       buf = kmap_atomic(page, KM_BIO_SRC_IRQ) + offset;
+               buf = kmap_atomic(page, KM_BIO_SRC_IRQ) + offset;
 
-       cmd->nleft -= nr_bytes;
-       cmd->cursg_ofs += nr_bytes;
+               cmd->nleft -= nr_bytes;
+               cmd->cursg_ofs += nr_bytes;
 
-       if (cmd->cursg_ofs == cursg->length) {
-               cmd->cursg = sg_next(cmd->cursg);
-               cmd->cursg_ofs = 0;
-       }
+               if (cmd->cursg_ofs == cursg->length) {
+                       cursg = cmd->cursg = sg_next(cmd->cursg);
+                       cmd->cursg_ofs = 0;
+               }
 
-       /* do the actual data transfer */
-       if (write)
-               hwif->tp_ops->output_data(drive, cmd, buf, nr_bytes);
-       else
-               hwif->tp_ops->input_data(drive, cmd, buf, nr_bytes);
+               /* do the actual data transfer */
+               if (write)
+                       hwif->tp_ops->output_data(drive, cmd, buf, nr_bytes);
+               else
+                       hwif->tp_ops->input_data(drive, cmd, buf, nr_bytes);
 
-       kunmap_atomic(buf, KM_BIO_SRC_IRQ);
+               kunmap_atomic(buf, KM_BIO_SRC_IRQ);
 #ifdef CONFIG_HIGHMEM
-       local_irq_restore(flags);
+               local_irq_restore(flags);
 #endif
-}
-
-static void ide_pio_multi(ide_drive_t *drive, struct ide_cmd *cmd,
-                         unsigned int write)
-{
-       unsigned int nsect;
 
-       nsect = min_t(unsigned int, cmd->nleft >> 9, drive->mult_count);
-       while (nsect--)
-               ide_pio_bytes(drive, cmd, write, SECTOR_SIZE);
+               len -= nr_bytes;
+       }
 }
 
 static void ide_pio_datablock(ide_drive_t *drive, struct ide_cmd *cmd,
                              unsigned int write)
 {
+       unsigned int nr_bytes;
+
        u8 saved_io_32bit = drive->io_32bit;
 
        if (cmd->tf_flags & IDE_TFLAG_FS)
@@ -263,9 +262,11 @@ static void ide_pio_datablock(ide_drive_t *drive, struct ide_cmd *cmd,
        touch_softlockup_watchdog();
 
        if (cmd->tf_flags & IDE_TFLAG_MULTI_PIO)
-               ide_pio_multi(drive, cmd, write);
+               nr_bytes = min_t(unsigned, cmd->nleft, drive->mult_count << 9);
        else
-               ide_pio_bytes(drive, cmd, write, SECTOR_SIZE);
+               nr_bytes = SECTOR_SIZE;
+
+       ide_pio_bytes(drive, cmd, write, nr_bytes);
 
        drive->io_32bit = saved_io_32bit;
 }