[PATCH] 2.5.67-ac2 direct-IO for IDE taskfile ioctl (1/4)

From: Bartlomiej Zolnierkiewicz (B.Zolnierkiewicz@elka.pw.edu.pl)
Date: Wed Apr 23 2003 - 12:38:40 EST


# Enhance bio_(un)map_user() and add blk_rq_bio_prep().
#
# Detailed changelog:
# - add blk_rq_bio_prep() helper for preparing non-fs bio based requests
# - bio_(un)map_user() -> __bio_(un)map_user()
# - add bio_(un)map_user() wrappers for __bio_(un)map_user(),
# bio_map_user() checks size of bio returned by __bio_map_user()
# and gets additional reference to bio (see comment inside)
# - update sg_io() to use new bio_(un)map_user() and blk_rq_bio_prep()
#
# Bartlomiej Zolnierkiewicz <bzolnier@elka.pw.edu.pl>

diff -uNr linux-2.5.67-ac2-tf4/drivers/block/ll_rw_blk.c linux/drivers/block/ll_rw_blk.c
--- linux-2.5.67-ac2-tf4/drivers/block/ll_rw_blk.c Wed Apr 23 15:14:11 2003
+++ linux/drivers/block/ll_rw_blk.c Wed Apr 23 15:19:27 2003
@@ -2274,6 +2274,21 @@
         return 1;
 }

+void blk_rq_bio_prep(request_queue_t *q, struct request *rq, struct bio *bio)
+{
+ /* first three bits are identical in rq->flags and bio->bi_rw */
+ rq->flags |= (bio->bi_rw & 7);
+
+ rq->nr_phys_segments = bio_phys_segments(q, bio);
+ rq->nr_hw_segments = bio_hw_segments(q, bio);
+ rq->current_nr_sectors = bio_cur_sectors(bio);
+ rq->hard_cur_sectors = rq->current_nr_sectors;
+ rq->hard_nr_sectors = rq->nr_sectors = bio_sectors(bio);
+ rq->buffer = bio_data(bio);
+
+ rq->hard_bio = rq->bio = rq->biotail = bio;
+}
+
 int __init blk_dev_init(void)
 {
         int total_ram = nr_free_pages() << (PAGE_SHIFT - 10);
@@ -2363,3 +2378,5 @@
 EXPORT_SYMBOL(__blk_stop_queue);
 EXPORT_SYMBOL(__blk_run_queue);
 EXPORT_SYMBOL(blk_run_queues);
+
+EXPORT_SYMBOL(blk_rq_bio_prep);
diff -uNr linux-2.5.67-ac2-tf4/drivers/block/scsi_ioctl.c linux/drivers/block/scsi_ioctl.c
--- linux-2.5.67-ac2-tf4/drivers/block/scsi_ioctl.c Sun Apr 13 00:07:39 2003
+++ linux/drivers/block/scsi_ioctl.c Tue Apr 22 17:57:22 2003
@@ -193,18 +193,8 @@
                  * be a write to vm.
                  */
                 bio = bio_map_user(bdev, uaddr, hdr.dxfer_len, reading);
- if (bio) {
- if (writing)
- bio->bi_rw |= (1 << BIO_RW);
-
- nr_sectors = (bio->bi_size + 511) >> 9;
-
- if (bio->bi_size < hdr.dxfer_len) {
- bio_endio(bio, bio->bi_size, 0);
- bio_unmap_user(bio, 0);
- bio = NULL;
- }
- }
+ if (bio && writing)
+ bio->bi_rw |= (1 << BIO_RW);

                 /*
                  * if bio setup failed, fall back to slow approach
@@ -243,21 +233,10 @@
         rq->hard_nr_sectors = rq->nr_sectors = nr_sectors;
         rq->hard_cur_sectors = rq->current_nr_sectors = nr_sectors;

- if (bio) {
- /*
- * subtle -- if bio_map_user() ended up bouncing a bio, it
- * would normally disappear when its bi_end_io is run.
- * however, we need it for the unmap, so grab an extra
- * reference to it
- */
- bio_get(bio);
+ rq->hard_bio = rq->bio = rq->biotail = bio;

- rq->nr_phys_segments = bio_phys_segments(q, bio);
- rq->nr_hw_segments = bio_hw_segments(q, bio);
- rq->current_nr_sectors = bio_cur_sectors(bio);
- rq->hard_cur_sectors = rq->current_nr_sectors;
- rq->buffer = bio_data(bio);
- }
+ if (bio)
+ blk_rq_bio_prep(q, rq, bio);

         rq->data_len = hdr.dxfer_len;
         rq->data = buffer;
@@ -268,8 +247,6 @@
         if (!rq->timeout)
                 rq->timeout = BLK_DEFAULT_TIMEOUT;

- rq->bio = rq->biotail = bio;
-
         start_time = jiffies;

         /* ignore return value. All information is passed back to caller
@@ -277,11 +254,9 @@
          * N.B. a non-zero SCSI status is _not_ necessarily an error.
          */
         blk_do_rq(q, bdev, rq);
-
- if (bio) {
+
+ if (bio)
                 bio_unmap_user(bio, reading);
- bio_put(bio);
- }

         /* write to all output members */
         hdr.status = rq->errors;
diff -uNr linux-2.5.67-ac2-tf4/fs/bio.c linux/fs/bio.c
--- linux-2.5.67-ac2-tf4/fs/bio.c Thu Apr 17 17:46:02 2003
+++ linux/fs/bio.c Tue Apr 22 17:55:03 2003
@@ -434,19 +434,9 @@
         return len;
 }

-/**
- * bio_map_user - map user address into bio
- * @bdev: destination block device
- * @uaddr: start of user address
- * @len: length in bytes
- * @write_to_vm: bool indicating writing to pages or not
- *
- * Map the user space address into a bio suitable for io to a block
- * device. Caller should check the size of the returned bio, we might
- * not have mapped the entire range specified.
- */
-struct bio *bio_map_user(struct block_device *bdev, unsigned long uaddr,
- unsigned int len, int write_to_vm)
+static struct bio *__bio_map_user(struct block_device *bdev,
+ unsigned long uaddr, unsigned int len,
+ int write_to_vm)
 {
         unsigned long end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
         unsigned long start = uaddr >> PAGE_SHIFT;
@@ -521,17 +511,42 @@
 }

 /**
- * bio_unmap_user - unmap a bio
- * @bio: the bio being unmapped
- * @write_to_vm: bool indicating whether pages were written to
- *
- * Unmap a bio previously mapped by bio_map_user(). The @write_to_vm
- * must be the same as passed into bio_map_user(). Must be called with
- * a process context.
+ * bio_map_user - map user address into bio
+ * @bdev: destination block device
+ * @uaddr: start of user address
+ * @len: length in bytes
+ * @write_to_vm: bool indicating writing to pages or not
  *
- * bio_unmap_user() may sleep.
+ * Map the user space address into a bio suitable for io to a block
+ * device.
  */
-void bio_unmap_user(struct bio *bio, int write_to_vm)
+struct bio *bio_map_user(struct block_device *bdev, unsigned long uaddr,
+ unsigned int len, int write_to_vm)
+{
+ struct bio *bio;
+
+ bio = __bio_map_user(bdev, uaddr, len, write_to_vm);
+
+ if (bio) {
+ if (bio->bi_size < len) {
+ bio_endio(bio, bio->bi_size, 0);
+ bio_unmap_user(bio, 0);
+ return NULL;
+ }
+
+ /*
+ * subtle -- if __bio_map_user() ended up bouncing a bio,
+ * it would normally disappear when its bi_end_io is run.
+ * however, we need it for the unmap, so grab an extra
+ * reference to it
+ */
+ bio_get(bio);
+ }
+
+ return bio;
+}
+
+static void __bio_unmap_user(struct bio *bio, int write_to_vm)
 {
         struct bio_vec *bvec;
         int i;
@@ -561,6 +576,23 @@
         bio_put(bio);
 }

+/**
+ * bio_unmap_user - unmap a bio
+ * @bio: the bio being unmapped
+ * @write_to_vm: bool indicating whether pages were written to
+ *
+ * Unmap a bio previously mapped by bio_map_user(). The @write_to_vm
+ * must be the same as passed into bio_map_user(). Must be called with
+ * a process context.
+ *
+ * bio_unmap_user() may sleep.
+ */
+void bio_unmap_user(struct bio *bio, int write_to_vm)
+{
+ __bio_unmap_user(bio, write_to_vm);
+ bio_put(bio);
+}
+
 /*
  * bio_set_pages_dirty() and bio_check_pages_dirty() are support functions
  * for performing direct-IO in BIOs.
diff -uNr linux-2.5.67-ac2-tf4/include/linux/blkdev.h linux/include/linux/blkdev.h
--- linux-2.5.67-ac2-tf4/include/linux/blkdev.h Fri Apr 18 02:03:38 2003
+++ linux/include/linux/blkdev.h Tue Apr 22 17:48:52 2003
@@ -432,6 +432,8 @@
 extern void blk_queue_invalidate_tags(request_queue_t *);
 extern void blk_congestion_wait(int rw, long timeout);

+extern void blk_rq_bio_prep(request_queue_t *, struct request *, struct bio *);
+
 #define MAX_PHYS_SEGMENTS 128
 #define MAX_HW_SEGMENTS 128
 #define MAX_SECTORS 255

-
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This archive was generated by hypermail 2b29 : Wed Apr 23 2003 - 22:00:37 EST