Merge git://oss.sgi.com:8090/xfs/xfs-2.6

[linux-drm-fsl-dcu.git] / drivers / scsi / st.c

diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index 488ec7948a570766856436970a40aa2fd3813528..16e279be4a3e17dd4422192ffa473b9b285d15a1 100644 (file)
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -9,7 +9,7 @@
    Steve Hirsch, Andreas Koppenh"ofer, Michael Leodolter, Eyal Lebedinsky,
    Michael Schaefer, J"org Weule, and Eric Youngdale.
 
-   Copyright 1992 - 2006 Kai Makisara
+   Copyright 1992 - 2007 Kai Makisara
    email Kai.Makisara@kolumbus.fi
 
    Some small formal changes - aeb, 950809
@@ -17,7 +17,7 @@
    Last modified: 18-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
  */
 
-static const char *verstr = "20061107";
+static const char *verstr = "20070203";
 
 #include <linux/module.h>
 
@@ -1168,6 +1168,7 @@ static int st_open(struct inode *inode, struct file *filp)
                STps = &(STp->ps[i]);
                STps->rw = ST_IDLE;
        }
+       STp->try_dio_now = STp->try_dio;
        STp->recover_count = 0;
        DEB( STp->nbr_waits = STp->nbr_finished = 0;
             STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = STp->nbr_combinable = 0; )
@@ -1400,9 +1401,9 @@ static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
        struct st_buffer *STbp = STp->buffer;
 
        if (is_read)
-               i = STp->try_dio && try_rdio;
+               i = STp->try_dio_now && try_rdio;
        else
-               i = STp->try_dio && try_wdio;
+               i = STp->try_dio_now && try_wdio;
 
        if (i && ((unsigned long)buf & queue_dma_alignment(
                                        STp->device->request_queue)) == 0) {
@@ -1599,7 +1600,7 @@ st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
                        STm->do_async_writes && STps->eof < ST_EOM_OK;
 
                if (STp->block_size != 0 && STm->do_buffer_writes &&
-                   !(STp->try_dio && try_wdio) && STps->eof < ST_EOM_OK &&
+                   !(STp->try_dio_now && try_wdio) && STps->eof < ST_EOM_OK &&
                    STbp->buffer_bytes < STbp->buffer_size) {
                        STp->dirty = 1;
                        /* Don't write a buffer that is not full enough. */
@@ -1769,7 +1770,7 @@ static long read_tape(struct scsi_tape *STp, long count,
        if (STp->block_size == 0)
                blks = bytes = count;
        else {
-               if (!(STp->try_dio && try_rdio) && STm->do_read_ahead) {
+               if (!(STp->try_dio_now && try_rdio) && STm->do_read_ahead) {
                        blks = (STp->buffer)->buffer_blocks;
                        bytes = blks * STp->block_size;
                } else {
@@ -1948,10 +1949,12 @@ st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
                goto out;
 
        STm = &(STp->modes[STp->current_mode]);
-       if (!(STm->do_read_ahead) && STp->block_size != 0 &&
-           (count % STp->block_size) != 0) {
-               retval = (-EINVAL);     /* Read must be integral number of blocks */
-               goto out;
+       if (STp->block_size != 0 && (count % STp->block_size) != 0) {
+               if (!STm->do_read_ahead) {
+                       retval = (-EINVAL);     /* Read must be integral number of blocks */
+                       goto out;
+               }
+               STp->try_dio_now = 0;  /* Direct i/o can't handle split blocks */
        }
 
        STps = &(STp->ps[STp->partition]);