2 files changed, 123 insertions, 145 deletions

diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index 053444b027d4..26e13dc7bcdb 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -50,7 +50,6 @@ static const char *verstr = "20050830";
 #include <scsi/scsi_eh.h>
 #include <scsi/scsi_host.h>
 #include <scsi/scsi_ioctl.h>
-#include <scsi/scsi_request.h>
 #include <scsi/sg.h>
 
 
@@ -188,8 +187,6 @@ static int from_buffer(struct st_buffer *, char __user *, int);
 static void move_buffer_data(struct st_buffer *, int);
 static void buf_to_sg(struct st_buffer *, unsigned int);
 
-static int st_map_user_pages(struct scatterlist *, const unsigned int, 
-                             unsigned long, size_t, int, unsigned long);
 static int sgl_map_user_pages(struct scatterlist *, const unsigned int, 
                               unsigned long, size_t, int);
 static int sgl_unmap_user_pages(struct scatterlist *, const unsigned int, int);
@@ -313,12 +310,13 @@ static inline char *tape_name(struct scsi_tape *tape)
 }
 
 
-static void st_analyze_sense(struct scsi_request *SRpnt, struct st_cmdstatus *s)
+static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
 {
         const u8 *ucp;
-        const u8 *sense = SRpnt->sr_sense_buffer;
+        const u8 *sense = SRpnt->sense;
 
-        s->have_sense = scsi_request_normalize_sense(SRpnt, &s->sense_hdr);
+        s->have_sense = scsi_normalize_sense(SRpnt->sense,
+                                SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
         s->flags = 0;
 
         if (s->have_sense) {
@@ -345,9 +343,9 @@ static void st_analyze_sense(struct scsi_request *SRpnt, struct st_cmdstatus *s)
 
 
 /* Convert the result to success code */
-static int st_chk_result(struct scsi_tape *STp, struct scsi_request * SRpnt)
+static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
 {
-        int result = SRpnt->sr_result;
+        int result = SRpnt->result;
         u8 scode;
         DEB(const char *stp;)
         char *name = tape_name(STp);
@@ -366,13 +364,12 @@ static int st_chk_result(struct scsi_tape *STp, struct scsi_request * SRpnt)
 
         DEB(
         if (debugging) {
-                printk(ST_DEB_MSG "%s: Error: %x, cmd: %x %x %x %x %x %x Len: %d\n",
+                printk(ST_DEB_MSG "%s: Error: %x, cmd: %x %x %x %x %x %x\n",
                        name, result,
-                       SRpnt->sr_cmnd[0], SRpnt->sr_cmnd[1], SRpnt->sr_cmnd[2],
-                       SRpnt->sr_cmnd[3], SRpnt->sr_cmnd[4], SRpnt->sr_cmnd[5],
-                       SRpnt->sr_bufflen);
+                       SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
+                       SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
                 if (cmdstatp->have_sense)
-                        scsi_print_req_sense("st", SRpnt);
+                         __scsi_print_sense("st", SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
         } ) /* end DEB */
         if (!debugging) { /* Abnormal conditions for tape */
                 if (!cmdstatp->have_sense)
@@ -386,20 +383,21 @@ static int st_chk_result(struct scsi_tape *STp, struct scsi_request * SRpnt)
                          /* scode != UNIT_ATTENTION && */
                          scode != BLANK_CHECK &&
                          scode != VOLUME_OVERFLOW &&
-                         SRpnt->sr_cmnd[0] != MODE_SENSE &&
-                         SRpnt->sr_cmnd[0] != TEST_UNIT_READY) {
+                         SRpnt->cmd[0] != MODE_SENSE &&
+                         SRpnt->cmd[0] != TEST_UNIT_READY) {
                                 printk(KERN_WARNING "%s: Error with sense data: ", name);
-                                scsi_print_req_sense("st", SRpnt);
+                                __scsi_print_sense("st", SRpnt->sense,
+                                                   SCSI_SENSE_BUFFERSIZE);
                 }
         }
 
         if (cmdstatp->fixed_format &&
             STp->cln_mode >= EXTENDED_SENSE_START) {  /* Only fixed format sense */
                 if (STp->cln_sense_value)
-                        STp->cleaning_req |= ((SRpnt->sr_sense_buffer[STp->cln_mode] &
+                        STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
                                                STp->cln_sense_mask) == STp->cln_sense_value);
                 else
-                        STp->cleaning_req |= ((SRpnt->sr_sense_buffer[STp->cln_mode] &
+                        STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
                                                STp->cln_sense_mask) != 0);
         }
         if (cmdstatp->have_sense &&
@@ -411,8 +409,8 @@ static int st_chk_result(struct scsi_tape *STp, struct scsi_request * SRpnt)
         if (cmdstatp->have_sense &&
             scode == RECOVERED_ERROR
 #if ST_RECOVERED_WRITE_FATAL
-            && SRpnt->sr_cmnd[0] != WRITE_6
-            && SRpnt->sr_cmnd[0] != WRITE_FILEMARKS
+            && SRpnt->cmd[0] != WRITE_6
+            && SRpnt->cmd[0] != WRITE_FILEMARKS
 #endif
             ) {
                 STp->recover_count++;
@@ -420,9 +418,9 @@ static int st_chk_result(struct scsi_tape *STp, struct scsi_request * SRpnt)
 
                 DEB(
                 if (debugging) {
-                        if (SRpnt->sr_cmnd[0] == READ_6)
+                        if (SRpnt->cmd[0] == READ_6)
                                 stp = "read";
-                        else if (SRpnt->sr_cmnd[0] == WRITE_6)
+                        else if (SRpnt->cmd[0] == WRITE_6)
                                 stp = "write";
                         else
                                 stp = "ioctl";
@@ -438,28 +436,37 @@ static int st_chk_result(struct scsi_tape *STp, struct scsi_request * SRpnt)
 
 
 /* Wakeup from interrupt */
-static void st_sleep_done(struct scsi_cmnd * SCpnt)
+static void st_sleep_done(void *data, char *sense, int result, int resid)
 {
-        struct scsi_tape *STp = container_of(SCpnt->request->rq_disk->private_data,
-                                             struct scsi_tape, driver);
+        struct st_request *SRpnt = data;
+        struct scsi_tape *STp = SRpnt->stp;
 
-        (STp->buffer)->cmdstat.midlevel_result = SCpnt->result;
-        SCpnt->request->rq_status = RQ_SCSI_DONE;
+        memcpy(SRpnt->sense, sense, SCSI_SENSE_BUFFERSIZE);
+        (STp->buffer)->cmdstat.midlevel_result = SRpnt->result = result;
         DEB( STp->write_pending = 0; )
 
-        if (SCpnt->request->waiting)
-                complete(SCpnt->request->waiting);
+        if (SRpnt->waiting)
+                complete(SRpnt->waiting);
+}
+
+static struct st_request *st_allocate_request(void)
+{
+        return kzalloc(sizeof(struct st_request), GFP_KERNEL);
+}
+
+static void st_release_request(struct st_request *streq)
+{
+        kfree(streq);
 }
 
 /* Do the scsi command. Waits until command performed if do_wait is true.
    Otherwise write_behind_check() is used to check that the command
    has finished. */
-static struct scsi_request *
-st_do_scsi(struct scsi_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
+static struct st_request *
+st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
            int bytes, int direction, int timeout, int retries, int do_wait)
 {
         struct completion *waiting;
-        unsigned char *bp;
 
         /* if async, make sure there's no command outstanding */
         if (!do_wait && ((STp->buffer)->last_SRpnt)) {
@@ -473,7 +480,7 @@ st_do_scsi(struct scsi_request * SRpnt, struct scsi_tape * STp, unsigned char *c
         }
 
         if (SRpnt == NULL) {
-                SRpnt = scsi_allocate_request(STp->device, GFP_ATOMIC);
+                SRpnt = st_allocate_request();
                 if (SRpnt == NULL) {
                         DEBC( printk(KERN_ERR "%s: Can't get SCSI request.\n",
                                      tape_name(STp)); );
@@ -483,6 +490,7 @@ st_do_scsi(struct scsi_request * SRpnt, struct scsi_tape * STp, unsigned char *c
                                 (STp->buffer)->syscall_result = (-EBUSY);
                         return NULL;
                 }
+                SRpnt->stp = STp;
         }
 
         /* If async IO, set last_SRpnt. This ptr tells write_behind_check
@@ -492,32 +500,26 @@ st_do_scsi(struct scsi_request * SRpnt, struct scsi_tape * STp, unsigned char *c
 
         waiting = &STp->wait;
         init_completion(waiting);
-        SRpnt->sr_use_sg = STp->buffer->do_dio || (bytes > (STp->buffer)->frp[0].length);
-        if (SRpnt->sr_use_sg) {
-                if (!STp->buffer->do_dio)
-                        buf_to_sg(STp->buffer, bytes);
-                SRpnt->sr_use_sg = (STp->buffer)->sg_segs;
-                bp = (char *) &((STp->buffer)->sg[0]);
-        } else
-                bp = (STp->buffer)->b_data;
-        SRpnt->sr_data_direction = direction;
-        SRpnt->sr_cmd_len = 0;
-        SRpnt->sr_request->waiting = waiting;
-        SRpnt->sr_request->rq_status = RQ_SCSI_BUSY;
-        SRpnt->sr_request->rq_disk = STp->disk;
-        SRpnt->sr_request->end_io = blk_end_sync_rq;
-        STp->buffer->cmdstat.have_sense = 0;
+        SRpnt->waiting = waiting;
 
-        scsi_do_req(SRpnt, (void *) cmd, bp, bytes,
-                    st_sleep_done, timeout, retries);
+        if (!STp->buffer->do_dio)
+                buf_to_sg(STp->buffer, bytes);
 
-        if (do_wait) {
+        memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
+        STp->buffer->cmdstat.have_sense = 0;
+        STp->buffer->syscall_result = 0;
+
+        if (scsi_execute_async(STp->device, cmd, direction,
+                        &((STp->buffer)->sg[0]), bytes, (STp->buffer)->sg_segs,
+                        timeout, retries, SRpnt, st_sleep_done, GFP_KERNEL))
+                /* could not allocate the buffer or request was too large */
+                (STp->buffer)->syscall_result = (-EBUSY);
+        else if (do_wait) {
                 wait_for_completion(waiting);
-                SRpnt->sr_request->waiting = NULL;
-                if (SRpnt->sr_request->rq_status != RQ_SCSI_DONE)
-                        SRpnt->sr_result |= (DRIVER_ERROR << 24);
+                SRpnt->waiting = NULL;
                 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
         }
+
         return SRpnt;
 }
 
@@ -532,7 +534,7 @@ static int write_behind_check(struct scsi_tape * STp)
         struct st_buffer *STbuffer;
         struct st_partstat *STps;
         struct st_cmdstatus *cmdstatp;
-        struct scsi_request *SRpnt;
+        struct st_request *SRpnt;
 
         STbuffer = STp->buffer;
         if (!STbuffer->writing)
@@ -548,12 +550,10 @@ static int write_behind_check(struct scsi_tape * STp)
         wait_for_completion(&(STp->wait));
         SRpnt = STbuffer->last_SRpnt;
         STbuffer->last_SRpnt = NULL;
-        SRpnt->sr_request->waiting = NULL;
-        if (SRpnt->sr_request->rq_status != RQ_SCSI_DONE)
-                SRpnt->sr_result |= (DRIVER_ERROR << 24);
+        SRpnt->waiting = NULL;
 
         (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
-        scsi_release_request(SRpnt);
+        st_release_request(SRpnt);
 
         STbuffer->buffer_bytes -= STbuffer->writing;
         STps = &(STp->ps[STp->partition]);
@@ -593,7 +593,7 @@ static int write_behind_check(struct scsi_tape * STp)
    it messes up the block number). */
 static int cross_eof(struct scsi_tape * STp, int forward)
 {
-        struct scsi_request *SRpnt;
+        struct st_request *SRpnt;
         unsigned char cmd[MAX_COMMAND_SIZE];
 
         cmd[0] = SPACE;
@@ -613,7 +613,7 @@ static int cross_eof(struct scsi_tape * STp, int forward)
         if (!SRpnt)
                 return (STp->buffer)->syscall_result;
 
-        scsi_release_request(SRpnt);
+        st_release_request(SRpnt);
         SRpnt = NULL;
 
         if ((STp->buffer)->cmdstat.midlevel_result != 0)
@@ -630,7 +630,7 @@ static int flush_write_buffer(struct scsi_tape * STp)
         int offset, transfer, blks;
         int result;
         unsigned char cmd[MAX_COMMAND_SIZE];
-        struct scsi_request *SRpnt;
+        struct st_request *SRpnt;
         struct st_partstat *STps;
 
         result = write_behind_check(STp);
@@ -688,7 +688,7 @@ static int flush_write_buffer(struct scsi_tape * STp)
                         STp->dirty = 0;
                         (STp->buffer)->buffer_bytes = 0;
                 }
-                scsi_release_request(SRpnt);
+                st_release_request(SRpnt);
                 SRpnt = NULL;
         }
         return result;
@@ -785,7 +785,7 @@ static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
 }
 
 
-/* Lock or unlock the drive door. Don't use when scsi_request allocated. */
+/* Lock or unlock the drive door. Don't use when st_request allocated. */
 static int do_door_lock(struct scsi_tape * STp, int do_lock)
 {
         int retval, cmd;
@@ -844,7 +844,7 @@ static int test_ready(struct scsi_tape *STp, int do_wait)
         int attentions, waits, max_wait, scode;
         int retval = CHKRES_READY, new_session = 0;
         unsigned char cmd[MAX_COMMAND_SIZE];
-        struct scsi_request *SRpnt = NULL;
+        struct st_request *SRpnt = NULL;
         struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
 
         max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
@@ -903,7 +903,7 @@ static int test_ready(struct scsi_tape *STp, int do_wait)
         }
 
         if (SRpnt != NULL)
-                scsi_release_request(SRpnt);
+                st_release_request(SRpnt);
         return retval;
 }
 
@@ -918,7 +918,7 @@ static int check_tape(struct scsi_tape *STp, struct file *filp)
         int i, retval, new_session = 0, do_wait;
         unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
         unsigned short st_flags = filp->f_flags;
-        struct scsi_request *SRpnt = NULL;
+        struct st_request *SRpnt = NULL;
         struct st_modedef *STm;
         struct st_partstat *STps;
         char *name = tape_name(STp);
@@ -993,7 +993,7 @@ static int check_tape(struct scsi_tape *STp, struct file *filp)
                         goto err_out;
                 }
 
-                if (!SRpnt->sr_result && !STp->buffer->cmdstat.have_sense) {
+                if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
                         STp->max_block = ((STp->buffer)->b_data[1] << 16) |
                             ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
                         STp->min_block = ((STp->buffer)->b_data[4] << 8) |
@@ -1045,7 +1045,7 @@ static int check_tape(struct scsi_tape *STp, struct file *filp)
                 }
                 STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
         }
-        scsi_release_request(SRpnt);
+        st_release_request(SRpnt);
         SRpnt = NULL;
         STp->inited = 1;
 
@@ -1196,7 +1196,7 @@ static int st_flush(struct file *filp)
 {
         int result = 0, result2;
         unsigned char cmd[MAX_COMMAND_SIZE];
-        struct scsi_request *SRpnt;
+        struct st_request *SRpnt;
         struct scsi_tape *STp = filp->private_data;
         struct st_modedef *STm = &(STp->modes[STp->current_mode]);
         struct st_partstat *STps = &(STp->ps[STp->partition]);
@@ -1249,7 +1249,7 @@ static int st_flush(struct file *filp)
                       cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
                      (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
                         /* Write successful at EOM */
-                        scsi_release_request(SRpnt);
+                        st_release_request(SRpnt);
                         SRpnt = NULL;
                         if (STps->drv_file >= 0)
                                 STps->drv_file++;
@@ -1259,7 +1259,7 @@ static int st_flush(struct file *filp)
                         STps->eof = ST_FM;
                 }
                 else { /* Write error */
-                        scsi_release_request(SRpnt);
+                        st_release_request(SRpnt);
                         SRpnt = NULL;
                         printk(KERN_ERR "%s: Error on write filemark.\n", name);
                         if (result == 0)
@@ -1400,11 +1400,11 @@ static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
                 i = STp->try_dio && try_rdio;
         else
                 i = STp->try_dio && try_wdio;
+
         if (i && ((unsigned long)buf & queue_dma_alignment(
                                         STp->device->request_queue)) == 0) {
-                i = st_map_user_pages(&(STbp->sg[0]), STbp->use_sg,
-                                      (unsigned long)buf, count, (is_read ? READ : WRITE),
-                                      STp->max_pfn);
+                i = sgl_map_user_pages(&(STbp->sg[0]), STbp->use_sg,
+                                      (unsigned long)buf, count, (is_read ? READ : WRITE));
                 if (i > 0) {
                         STbp->do_dio = i;
                         STbp->buffer_bytes = 0;   /* can be used as transfer counter */
@@ -1472,7 +1472,7 @@ st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
         int async_write;
         unsigned char cmd[MAX_COMMAND_SIZE];
         const char __user *b_point;
-        struct scsi_request *SRpnt = NULL;
+        struct st_request *SRpnt = NULL;
         struct scsi_tape *STp = filp->private_data;
         struct st_modedef *STm;
         struct st_partstat *STps;
@@ -1624,7 +1624,7 @@ st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
                         retval = STbp->syscall_result;
                         goto out;
                 }
-                if (async_write) {
+                if (async_write && !STbp->syscall_result) {
                         STbp->writing = transfer;
                         STp->dirty = !(STbp->writing ==
                                        STbp->buffer_bytes);
@@ -1698,7 +1698,7 @@ st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
                         } else {
                                 count += do_count;
                                 STps->drv_block = (-1);         /* Too cautious? */
-                                retval = (-EIO);
+                                retval = STbp->syscall_result;
                         }
 
                 }
@@ -1728,7 +1728,7 @@ st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
 
  out:
         if (SRpnt != NULL)
-                scsi_release_request(SRpnt);
+                st_release_request(SRpnt);
         release_buffering(STp);
         up(&STp->lock);
 
@@ -1742,11 +1742,11 @@ st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
    Does release user buffer mapping if it is set.
 */
 static long read_tape(struct scsi_tape *STp, long count,
-                      struct scsi_request ** aSRpnt)
+                      struct st_request ** aSRpnt)
 {
         int transfer, blks, bytes;
         unsigned char cmd[MAX_COMMAND_SIZE];
-        struct scsi_request *SRpnt;
+        struct st_request *SRpnt;
         struct st_modedef *STm;
         struct st_partstat *STps;
         struct st_buffer *STbp;
@@ -1802,10 +1802,10 @@ static long read_tape(struct scsi_tape *STp, long count,
                 retval = 1;
                 DEBC(printk(ST_DEB_MSG "%s: Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
                             name,
-                            SRpnt->sr_sense_buffer[0], SRpnt->sr_sense_buffer[1],
-                            SRpnt->sr_sense_buffer[2], SRpnt->sr_sense_buffer[3],
-                            SRpnt->sr_sense_buffer[4], SRpnt->sr_sense_buffer[5],
-                            SRpnt->sr_sense_buffer[6], SRpnt->sr_sense_buffer[7]));
+                            SRpnt->sense[0], SRpnt->sense[1],
+                            SRpnt->sense[2], SRpnt->sense[3],
+                            SRpnt->sense[4], SRpnt->sense[5],
+                            SRpnt->sense[6], SRpnt->sense[7]));
                 if (cmdstatp->have_sense) {
 
                         if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
@@ -1835,7 +1835,7 @@ static long read_tape(struct scsi_tape *STp, long count,
                                                 }
                                                 STbp->buffer_bytes = bytes - transfer;
                                         } else {
-                                                scsi_release_request(SRpnt);
+                                                st_release_request(SRpnt);
                                                 SRpnt = *aSRpnt = NULL;
                                                 if (transfer == blks) { /* We did not get anything, error */
                                                         printk(KERN_NOTICE "%s: Incorrect block size.\n", name);
@@ -1929,7 +1929,7 @@ st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
         ssize_t retval = 0;
         ssize_t i, transfer;
         int special, do_dio = 0;
-        struct scsi_request *SRpnt = NULL;
+        struct st_request *SRpnt = NULL;
         struct scsi_tape *STp = filp->private_data;
         struct st_modedef *STm;
         struct st_partstat *STps;
@@ -2054,7 +2054,7 @@ st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
 
  out:
         if (SRpnt != NULL) {
-                scsi_release_request(SRpnt);
+                st_release_request(SRpnt);
                 SRpnt = NULL;
         }
         if (do_dio) {
@@ -2284,7 +2284,7 @@ static int st_set_options(struct scsi_tape *STp, long options)
 static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
 {
         unsigned char cmd[MAX_COMMAND_SIZE];
-        struct scsi_request *SRpnt = NULL;
+        struct st_request *SRpnt = NULL;
 
         memset(cmd, 0, MAX_COMMAND_SIZE);
         cmd[0] = MODE_SENSE;
@@ -2298,7 +2298,7 @@ static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
         if (SRpnt == NULL)
                 return (STp->buffer)->syscall_result;
 
-        scsi_release_request(SRpnt);
+        st_release_request(SRpnt);
 
         return (STp->buffer)->syscall_result;
 }
@@ -2310,7 +2310,7 @@ static int write_mode_page(struct scsi_tape *STp, int page, int slow)
 {
         int pgo;
         unsigned char cmd[MAX_COMMAND_SIZE];
-        struct scsi_request *SRpnt = NULL;
+        struct st_request *SRpnt = NULL;
 
         memset(cmd, 0, MAX_COMMAND_SIZE);
         cmd[0] = MODE_SELECT;
@@ -2329,7 +2329,7 @@ static int write_mode_page(struct scsi_tape *STp, int page, int slow)
         if (SRpnt == NULL)
                 return (STp->buffer)->syscall_result;
 
-        scsi_release_request(SRpnt);
+        st_release_request(SRpnt);
 
         return (STp->buffer)->syscall_result;
 }
@@ -2412,7 +2412,7 @@ static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_cod
         DEB( char *name = tape_name(STp); )
         unsigned char cmd[MAX_COMMAND_SIZE];
         struct st_partstat *STps;
-        struct scsi_request *SRpnt;
+        struct st_request *SRpnt;
 
         if (STp->ready != ST_READY && !load_code) {
                 if (STp->ready == ST_NO_TAPE)
@@ -2455,7 +2455,7 @@ static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_cod
                 return (STp->buffer)->syscall_result;
 
         retval = (STp->buffer)->syscall_result;
-        scsi_release_request(SRpnt);
+        st_release_request(SRpnt);
 
         if (!retval) {  /* SCSI command successful */
 
@@ -2503,7 +2503,7 @@ static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned lon
         int ioctl_result;
         int chg_eof = 1;
         unsigned char cmd[MAX_COMMAND_SIZE];
-        struct scsi_request *SRpnt;
+        struct st_request *SRpnt;
         struct st_partstat *STps;
         int fileno, blkno, at_sm, undone;
         int datalen = 0, direction = DMA_NONE;
@@ -2757,7 +2757,7 @@ static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned lon
         ioctl_result = (STp->buffer)->syscall_result;
 
         if (!ioctl_result) {    /* SCSI command successful */
-                scsi_release_request(SRpnt);
+                st_release_request(SRpnt);
                 SRpnt = NULL;
                 STps->drv_block = blkno;
                 STps->drv_file = fileno;
@@ -2872,7 +2872,7 @@ static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned lon
                                 /* Try the other possible state of Page Format if not
                                    already tried */
                                 STp->use_pf = !STp->use_pf | PF_TESTED;
-                                scsi_release_request(SRpnt);
+                                st_release_request(SRpnt);
                                 SRpnt = NULL;
                                 return st_int_ioctl(STp, cmd_in, arg);
                         }
@@ -2882,7 +2882,7 @@ static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned lon
                 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
                         STps->eof = ST_EOD;
 
-                scsi_release_request(SRpnt);
+                st_release_request(SRpnt);
                 SRpnt = NULL;
         }
 
@@ -2898,7 +2898,7 @@ static int get_location(struct scsi_tape *STp, unsigned int *block, int *partiti
 {
         int result;
         unsigned char scmd[MAX_COMMAND_SIZE];
-        struct scsi_request *SRpnt;
+        struct st_request *SRpnt;
         DEB( char *name = tape_name(STp); )
 
         if (STp->ready != ST_READY)
@@ -2944,7 +2944,7 @@ static int get_location(struct scsi_tape *STp, unsigned int *block, int *partiti
                 DEBC(printk(ST_DEB_MSG "%s: Got tape pos. blk %d part %d.\n", name,
                             *block, *partition));
         }
-        scsi_release_request(SRpnt);
+        st_release_request(SRpnt);
         SRpnt = NULL;
 
         return result;
@@ -2961,7 +2961,7 @@ static int set_location(struct scsi_tape *STp, unsigned int block, int partition
         unsigned int blk;
         int timeout;
         unsigned char scmd[MAX_COMMAND_SIZE];
-        struct scsi_request *SRpnt;
+        struct st_request *SRpnt;
         DEB( char *name = tape_name(STp); )
 
         if (STp->ready != ST_READY)
@@ -3047,7 +3047,7 @@ static int set_location(struct scsi_tape *STp, unsigned int block, int partition
                 result = 0;
         }
 
-        scsi_release_request(SRpnt);
+        st_release_request(SRpnt);
         SRpnt = NULL;
 
         return result;
@@ -3577,7 +3577,7 @@ static long st_compat_ioctl(struct file *file, unsigned int cmd, unsigned long a
 static struct st_buffer *
  new_tape_buffer(int from_initialization, int need_dma, int max_sg)
 {
-        int i, got = 0, segs = 0;
+        int i, got = 0;
         gfp_t priority;
         struct st_buffer *tb;
 
@@ -3594,10 +3594,8 @@ static struct st_buffer *
                 return NULL;
         }
         memset(tb, 0, i);
-        tb->frp_segs = tb->orig_frp_segs = segs;
+        tb->frp_segs = tb->orig_frp_segs = 0;
         tb->use_sg = max_sg;
-        if (segs > 0)
-                tb->b_data = page_address(tb->sg[0].page);
         tb->frp = (struct st_buf_fragment *)(&(tb->sg[0]) + max_sg);
 
         tb->in_use = 1;
@@ -3628,7 +3626,7 @@ static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dm
         priority = GFP_KERNEL | __GFP_NOWARN;
         if (need_dma)
                 priority |= GFP_DMA;
-        for (b_size = PAGE_SIZE, order=0;
+        for (b_size = PAGE_SIZE, order=0; order <= 6 &&
              b_size < new_size - STbuffer->buffer_size;
              order++, b_size *= 2)
                 ;  /* empty */
@@ -3670,6 +3668,7 @@ static void normalize_buffer(struct st_buffer * STbuffer)
         }
         STbuffer->frp_segs = STbuffer->orig_frp_segs;
         STbuffer->frp_sg_current = 0;
+        STbuffer->sg_segs = 0;
 }
 
 
@@ -3882,7 +3881,6 @@ static int st_probe(struct device *dev)
         struct st_buffer *buffer;
         int i, j, mode, dev_num, error;
         char *stp;
-        u64 bounce_limit;
 
         if (SDp->type != TYPE_TAPE)
                 return -ENODEV;
@@ -3892,7 +3890,8 @@ static int st_probe(struct device *dev)
                 return -ENODEV;
         }
 
-        i = SDp->host->sg_tablesize;
+        i = min(SDp->request_queue->max_hw_segments,
+                SDp->request_queue->max_phys_segments);
         if (st_max_sg_segs < i)
                 i = st_max_sg_segs;
         buffer = new_tape_buffer(1, (SDp->host)->unchecked_isa_dma, i);
@@ -3994,11 +3993,6 @@ static int st_probe(struct device *dev)
         tpnt->long_timeout = ST_LONG_TIMEOUT;
         tpnt->try_dio = try_direct_io && !SDp->host->unchecked_isa_dma;
 
-        bounce_limit = scsi_calculate_bounce_limit(SDp->host) >> PAGE_SHIFT;
-        if (bounce_limit > ULONG_MAX)
-                bounce_limit = ULONG_MAX;
-        tpnt->max_pfn = bounce_limit;
-
         for (i = 0; i < ST_NBR_MODES; i++) {
                 STm = &(tpnt->modes[i]);
                 STm->defined = 0;
@@ -4077,9 +4071,9 @@ static int st_probe(struct device *dev)
 
         sdev_printk(KERN_WARNING, SDp,
                     "Attached scsi tape %s", tape_name(tpnt));
-        printk(KERN_WARNING "%s: try direct i/o: %s (alignment %d B), max page reachable by HBA %lu\n",
+        printk(KERN_WARNING "%s: try direct i/o: %s (alignment %d B)\n",
                tape_name(tpnt), tpnt->try_dio ? "yes" : "no",
-               queue_dma_alignment(SDp->request_queue) + 1, tpnt->max_pfn);
+               queue_dma_alignment(SDp->request_queue) + 1);
 
         return 0;
 
@@ -4411,34 +4405,6 @@ static void do_create_class_files(struct scsi_tape *STp, int dev_num, int mode)
         return;
 }
 
-
-/* Pin down user pages and put them into a scatter gather list. Returns <= 0 if
-   - mapping of all pages not successful
-   - any page is above max_pfn
-   (i.e., either completely successful or fails)
-*/
-static int st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages, 
-                             unsigned long uaddr, size_t count, int rw,
-                             unsigned long max_pfn)
-{
-        int i, nr_pages;
-
-        nr_pages = sgl_map_user_pages(sgl, max_pages, uaddr, count, rw);
-        if (nr_pages <= 0)
-                return nr_pages;
-
-        for (i=0; i < nr_pages; i++) {
-                if (page_to_pfn(sgl[i].page) > max_pfn)
-                        goto out_unmap;
-        }
-        return nr_pages;
-
- out_unmap:
-        sgl_unmap_user_pages(sgl, nr_pages, 0);
-        return 0;
-}
-
-
 /* The following functions may be useful for a larger audience. */
 static int sgl_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages, 
                               unsigned long uaddr, size_t count, int rw)
diff --git a/drivers/scsi/st.h b/drivers/scsi/st.h
index 790acac160bc..411209048d74 100644
--- a/drivers/scsi/st.h
+++ b/drivers/scsi/st.h
@@ -4,6 +4,7 @@
 
 #include <linux/completion.h>
 #include <linux/kref.h>
+#include <scsi/scsi_cmnd.h>
 
 /* Descriptor for analyzed sense data */
 struct st_cmdstatus {
@@ -17,6 +18,17 @@ struct st_cmdstatus {
         u8 deferred;
 };
 
+struct scsi_tape;
+
+/* scsi tape command */
+struct st_request {
+        unsigned char cmd[MAX_COMMAND_SIZE];
+        unsigned char sense[SCSI_SENSE_BUFFERSIZE];
+        int result;
+        struct scsi_tape *stp;
+        struct completion *waiting;
+};
+
 /* The tape buffer descriptor. */
 struct st_buffer {
         unsigned char in_use;
@@ -28,7 +40,7 @@ struct st_buffer {
         int read_pointer;
         int writing;
         int syscall_result;
-        struct scsi_request *last_SRpnt;
+        struct st_request *last_SRpnt;
         struct st_cmdstatus cmdstat;
         unsigned char *b_data;
         unsigned short use_sg;  /* zero or max number of s/g segments for this adapter */