[SCSI] add scsi_mode_select to scsi_lib.c

This complements the scsi_mode_sense() function

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 80 insertions, 1 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 9a05076f9cf4..ede158d08d9d 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -1811,6 +1811,84 @@ void scsi_exit_queue(void)
                 kmem_cache_destroy(sgp->slab);
         }
 }
+
+/**
+ *      scsi_mode_select - issue a mode select
+ *      @sdev:  SCSI device to be queried
+ *      @pf:    Page format bit (1 == standard, 0 == vendor specific)
+ *      @sp:    Save page bit (0 == don't save, 1 == save)
+ *      @modepage: mode page being requested
+ *      @buffer: request buffer (may not be smaller than eight bytes)
+ *      @len:   length of request buffer.
+ *      @timeout: command timeout
+ *      @retries: number of retries before failing
+ *      @data: returns a structure abstracting the mode header data
+ *      @sense: place to put sense data (or NULL if no sense to be collected).
+ *              must be SCSI_SENSE_BUFFERSIZE big.
+ *
+ *      Returns zero if successful; negative error number or scsi
+ *      status on error
+ *
+ */
+int
+scsi_mode_select(struct scsi_device *sdev, int pf, int sp, int modepage,
+                 unsigned char *buffer, int len, int timeout, int retries,
+                 struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
+{
+        unsigned char cmd[10];
+        unsigned char *real_buffer;
+        int ret;
+
+        memset(cmd, 0, sizeof(cmd));
+        cmd[1] = (pf ? 0x10 : 0) | (sp ? 0x01 : 0);
+
+        if (sdev->use_10_for_ms) {
+                if (len > 65535)
+                        return -EINVAL;
+                real_buffer = kmalloc(8 + len, GFP_KERNEL);
+                if (!real_buffer)
+                        return -ENOMEM;
+                memcpy(real_buffer + 8, buffer, len);
+                len += 8;
+                real_buffer[0] = 0;
+                real_buffer[1] = 0;
+                real_buffer[2] = data->medium_type;
+                real_buffer[3] = data->device_specific;
+                real_buffer[4] = data->longlba ? 0x01 : 0;
+                real_buffer[5] = 0;
+                real_buffer[6] = data->block_descriptor_length >> 8;
+                real_buffer[7] = data->block_descriptor_length;
+
+                cmd[0] = MODE_SELECT_10;
+                cmd[7] = len >> 8;
+                cmd[8] = len;
+        } else {
+                if (len > 255 || data->block_descriptor_length > 255 ||
+                    data->longlba)
+                        return -EINVAL;
+
+                real_buffer = kmalloc(4 + len, GFP_KERNEL);
+                if (!real_buffer)
+                        return -ENOMEM;
+                memcpy(real_buffer + 4, buffer, len);
+                len += 4;
+                real_buffer[0] = 0;
+                real_buffer[1] = data->medium_type;
+                real_buffer[2] = data->device_specific;
+                real_buffer[3] = data->block_descriptor_length;
+                
+
+                cmd[0] = MODE_SELECT;
+                cmd[4] = len;
+        }
+
+        ret = scsi_execute_req(sdev, cmd, DMA_TO_DEVICE, real_buffer, len,
+                               sshdr, timeout, retries);
+        kfree(real_buffer);
+        return ret;
+}
+EXPORT_SYMBOL_GPL(scsi_mode_select);
+
 /**
  *      scsi_mode_sense - issue a mode sense, falling back from 10 to 
  *              six bytes if necessary.
@@ -1832,7 +1910,8 @@ void scsi_exit_queue(void)
 int
 scsi_mode_sense(struct scsi_device *sdev, int dbd, int modepage,
                   unsigned char *buffer, int len, int timeout, int retries,
-                  struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr) {
+                  struct scsi_mode_data *data, struct scsi_sense_hdr *sshdr)
+{
         unsigned char cmd[12];
         int use_10_for_ms;
         int header_length;