Bias the location of pages freed for min_free_kbytes in the same MAX_ORDER_NR_PAGES...
[sfrench/cifs-2.6.git] / block / ll_rw_blk.c
index ed39313c408534ee832e4ff61c428ba46c8b2c12..a83823fcd74f3f90a42d8a470cad9947c5cdd56f 100644 (file)
@@ -42,6 +42,9 @@ static void drive_stat_acct(struct request *rq, int nr_sectors, int new_io);
 static void init_request_from_bio(struct request *req, struct bio *bio);
 static int __make_request(struct request_queue *q, struct bio *bio);
 static struct io_context *current_io_context(gfp_t gfp_flags, int node);
+static void blk_recalc_rq_segments(struct request *rq);
+static void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
+                           struct bio *bio);
 
 /*
  * For the allocated request tables
@@ -428,7 +431,6 @@ static void queue_flush(struct request_queue *q, unsigned which)
 static inline struct request *start_ordered(struct request_queue *q,
                                            struct request *rq)
 {
-       q->bi_size = 0;
        q->orderr = 0;
        q->ordered = q->next_ordered;
        q->ordseq |= QUEUE_ORDSEQ_STARTED;
@@ -525,56 +527,36 @@ int blk_do_ordered(struct request_queue *q, struct request **rqp)
        return 1;
 }
 
-static int flush_dry_bio_endio(struct bio *bio, unsigned int bytes, int error)
-{
-       struct request_queue *q = bio->bi_private;
-
-       /*
-        * This is dry run, restore bio_sector and size.  We'll finish
-        * this request again with the original bi_end_io after an
-        * error occurs or post flush is complete.
-        */
-       q->bi_size += bytes;
-
-       if (bio->bi_size)
-               return 1;
-
-       /* Reset bio */
-       set_bit(BIO_UPTODATE, &bio->bi_flags);
-       bio->bi_size = q->bi_size;
-       bio->bi_sector -= (q->bi_size >> 9);
-       q->bi_size = 0;
-
-       return 0;
-}
-
-static int ordered_bio_endio(struct request *rq, struct bio *bio,
-                            unsigned int nbytes, int error)
+static void req_bio_endio(struct request *rq, struct bio *bio,
+                         unsigned int nbytes, int error)
 {
        struct request_queue *q = rq->q;
-       bio_end_io_t *endio;
-       void *private;
 
-       if (&q->bar_rq != rq)
-               return 0;
+       if (&q->bar_rq != rq) {
+               if (error)
+                       clear_bit(BIO_UPTODATE, &bio->bi_flags);
+               else if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
+                       error = -EIO;
 
-       /*
-        * Okay, this is the barrier request in progress, dry finish it.
-        */
-       if (error && !q->orderr)
-               q->orderr = error;
-
-       endio = bio->bi_end_io;
-       private = bio->bi_private;
-       bio->bi_end_io = flush_dry_bio_endio;
-       bio->bi_private = q;
-
-       bio_endio(bio, nbytes, error);
+               if (unlikely(nbytes > bio->bi_size)) {
+                       printk("%s: want %u bytes done, only %u left\n",
+                              __FUNCTION__, nbytes, bio->bi_size);
+                       nbytes = bio->bi_size;
+               }
 
-       bio->bi_end_io = endio;
-       bio->bi_private = private;
+               bio->bi_size -= nbytes;
+               bio->bi_sector += (nbytes >> 9);
+               if (bio->bi_size == 0)
+                       bio_endio(bio, error);
+       } else {
 
-       return 1;
+               /*
+                * Okay, this is the barrier request in progress, just
+                * record the error;
+                */
+               if (error && !q->orderr)
+                       q->orderr = error;
+       }
 }
 
 /**
@@ -1220,16 +1202,40 @@ EXPORT_SYMBOL(blk_dump_rq_flags);
 
 void blk_recount_segments(struct request_queue *q, struct bio *bio)
 {
+       struct request rq;
+       struct bio *nxt = bio->bi_next;
+       rq.q = q;
+       rq.bio = rq.biotail = bio;
+       bio->bi_next = NULL;
+       blk_recalc_rq_segments(&rq);
+       bio->bi_next = nxt;
+       bio->bi_phys_segments = rq.nr_phys_segments;
+       bio->bi_hw_segments = rq.nr_hw_segments;
+       bio->bi_flags |= (1 << BIO_SEG_VALID);
+}
+EXPORT_SYMBOL(blk_recount_segments);
+
+static void blk_recalc_rq_segments(struct request *rq)
+{
+       int nr_phys_segs;
+       int nr_hw_segs;
+       unsigned int phys_size;
+       unsigned int hw_size;
        struct bio_vec *bv, *bvprv = NULL;
-       int i, nr_phys_segs, nr_hw_segs, seg_size, hw_seg_size, cluster;
+       int seg_size;
+       int hw_seg_size;
+       int cluster;
+       struct req_iterator iter;
        int high, highprv = 1;
+       struct request_queue *q = rq->q;
 
-       if (unlikely(!bio->bi_io_vec))
+       if (!rq->bio)
                return;
 
        cluster = q->queue_flags & (1 << QUEUE_FLAG_CLUSTER);
-       hw_seg_size = seg_size = nr_phys_segs = nr_hw_segs = 0;
-       bio_for_each_segment(bv, bio, i) {
+       hw_seg_size = seg_size = 0;
+       phys_size = hw_size = nr_phys_segs = nr_hw_segs = 0;
+       rq_for_each_segment(bv, rq, iter) {
                /*
                 * the trick here is making sure that a high page is never
                 * considered part of another segment, since that might
@@ -1255,12 +1261,13 @@ void blk_recount_segments(struct request_queue *q, struct bio *bio)
                }
 new_segment:
                if (BIOVEC_VIRT_MERGEABLE(bvprv, bv) &&
-                   !BIOVEC_VIRT_OVERSIZE(hw_seg_size + bv->bv_len)) {
+                   !BIOVEC_VIRT_OVERSIZE(hw_seg_size + bv->bv_len))
                        hw_seg_size += bv->bv_len;
-               else {
+               else {
 new_hw_segment:
-                       if (hw_seg_size > bio->bi_hw_front_size)
-                               bio->bi_hw_front_size = hw_seg_size;
+                       if (nr_hw_segs == 1 &&
+                           hw_seg_size > rq->bio->bi_hw_front_size)
+                               rq->bio->bi_hw_front_size = hw_seg_size;
                        hw_seg_size = BIOVEC_VIRT_START_SIZE(bv) + bv->bv_len;
                        nr_hw_segs++;
                }
@@ -1270,15 +1277,15 @@ new_hw_segment:
                seg_size = bv->bv_len;
                highprv = high;
        }
-       if (hw_seg_size > bio->bi_hw_back_size)
-               bio->bi_hw_back_size = hw_seg_size;
-       if (nr_hw_segs == 1 && hw_seg_size > bio->bi_hw_front_size)
-               bio->bi_hw_front_size = hw_seg_size;
-       bio->bi_phys_segments = nr_phys_segs;
-       bio->bi_hw_segments = nr_hw_segs;
-       bio->bi_flags |= (1 << BIO_SEG_VALID);
+
+       if (nr_hw_segs == 1 &&
+           hw_seg_size > rq->bio->bi_hw_front_size)
+               rq->bio->bi_hw_front_size = hw_seg_size;
+       if (hw_seg_size > rq->biotail->bi_hw_back_size)
+               rq->biotail->bi_hw_back_size = hw_seg_size;
+       rq->nr_phys_segments = nr_phys_segs;
+       rq->nr_hw_segments = nr_hw_segs;
 }
-EXPORT_SYMBOL(blk_recount_segments);
 
 static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio,
                                   struct bio *nxt)
@@ -1325,8 +1332,8 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq,
                  struct scatterlist *sg)
 {
        struct bio_vec *bvec, *bvprv;
-       struct bio *bio;
-       int nsegs, i, cluster;
+       struct req_iterator iter;
+       int nsegs, cluster;
 
        nsegs = 0;
        cluster = q->queue_flags & (1 << QUEUE_FLAG_CLUSTER);
@@ -1335,35 +1342,30 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq,
         * for each bio in rq
         */
        bvprv = NULL;
-       rq_for_each_bio(bio, rq) {
-               /*
-                * for each segment in bio
-                */
-               bio_for_each_segment(bvec, bio, i) {
-                       int nbytes = bvec->bv_len;
+       rq_for_each_segment(bvec, rq, iter) {
+               int nbytes = bvec->bv_len;
 
-                       if (bvprv && cluster) {
-                               if (sg[nsegs - 1].length + nbytes > q->max_segment_size)
-                                       goto new_segment;
+               if (bvprv && cluster) {
+                       if (sg[nsegs - 1].length + nbytes > q->max_segment_size)
+                               goto new_segment;
 
-                               if (!BIOVEC_PHYS_MERGEABLE(bvprv, bvec))
-                                       goto new_segment;
-                               if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bvec))
-                                       goto new_segment;
+                       if (!BIOVEC_PHYS_MERGEABLE(bvprv, bvec))
+                               goto new_segment;
+                       if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bvec))
+                               goto new_segment;
 
-                               sg[nsegs - 1].length += nbytes;
-                       } else {
+                       sg[nsegs - 1].length += nbytes;
+               } else {
 new_segment:
-                               memset(&sg[nsegs],0,sizeof(struct scatterlist));
-                               sg[nsegs].page = bvec->bv_page;
-                               sg[nsegs].length = nbytes;
-                               sg[nsegs].offset = bvec->bv_offset;
+                       memset(&sg[nsegs],0,sizeof(struct scatterlist));
+                       sg[nsegs].page = bvec->bv_page;
+                       sg[nsegs].length = nbytes;
+                       sg[nsegs].offset = bvec->bv_offset;
 
-                               nsegs++;
-                       }
-                       bvprv = bvec;
-               } /* segments in bio */
-       } /* bios in rq */
+                       nsegs++;
+               }
+               bvprv = bvec;
+       } /* segments in rq */
 
        return nsegs;
 }
@@ -1420,7 +1422,8 @@ static inline int ll_new_hw_segment(struct request_queue *q,
        return 1;
 }
 
-int ll_back_merge_fn(struct request_queue *q, struct request *req, struct bio *bio)
+static int ll_back_merge_fn(struct request_queue *q, struct request *req,
+                           struct bio *bio)
 {
        unsigned short max_sectors;
        int len;
@@ -1456,7 +1459,6 @@ int ll_back_merge_fn(struct request_queue *q, struct request *req, struct bio *b
 
        return ll_new_hw_segment(q, req, bio);
 }
-EXPORT_SYMBOL(ll_back_merge_fn);
 
 static int ll_front_merge_fn(struct request_queue *q, struct request *req, 
                             struct bio *bio)
@@ -1852,7 +1854,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
 
        init_timer(&q->unplug_timer);
 
-       snprintf(q->kobj.name, KOBJ_NAME_LEN, "%s", "queue");
+       kobject_set_name(&q->kobj, "%s", "queue");
        q->kobj.ktype = &queue_ktype;
        kobject_init(&q->kobj);
 
@@ -2346,6 +2348,23 @@ static int __blk_rq_unmap_user(struct bio *bio)
        return ret;
 }
 
+int blk_rq_append_bio(struct request_queue *q, struct request *rq,
+                     struct bio *bio)
+{
+       if (!rq->bio)
+               blk_rq_bio_prep(q, rq, bio);
+       else if (!ll_back_merge_fn(q, rq, bio))
+               return -EINVAL;
+       else {
+               rq->biotail->bi_next = bio;
+               rq->biotail = bio;
+
+               rq->data_len += bio->bi_size;
+       }
+       return 0;
+}
+EXPORT_SYMBOL(blk_rq_append_bio);
+
 static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
                             void __user *ubuf, unsigned int len)
 {
@@ -2377,23 +2396,12 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq,
         */
        bio_get(bio);
 
-       if (!rq->bio)
-               blk_rq_bio_prep(q, rq, bio);
-       else if (!ll_back_merge_fn(q, rq, bio)) {
-               ret = -EINVAL;
-               goto unmap_bio;
-       } else {
-               rq->biotail->bi_next = bio;
-               rq->biotail = bio;
+       ret = blk_rq_append_bio(q, rq, bio);
+       if (!ret)
+               return bio->bi_size;
 
-               rq->data_len += bio->bi_size;
-       }
-
-       return bio->bi_size;
-
-unmap_bio:
        /* if it was boucned we must call the end io function */
-       bio_endio(bio, bio->bi_size, 0);
+       bio_endio(bio, 0);
        __blk_rq_unmap_user(orig_bio);
        bio_put(bio);
        return ret;
@@ -2502,7 +2510,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
                return PTR_ERR(bio);
 
        if (bio->bi_size != len) {
-               bio_endio(bio, bio->bi_size, 0);
+               bio_endio(bio, 0);
                bio_unmap_user(bio);
                return -EINVAL;
        }
@@ -2912,15 +2920,9 @@ static void init_request_from_bio(struct request *req, struct bio *bio)
 
        req->errors = 0;
        req->hard_sector = req->sector = bio->bi_sector;
-       req->hard_nr_sectors = req->nr_sectors = bio_sectors(bio);
-       req->current_nr_sectors = req->hard_cur_sectors = bio_cur_sectors(bio);
-       req->nr_phys_segments = bio_phys_segments(req->q, bio);
-       req->nr_hw_segments = bio_hw_segments(req->q, bio);
-       req->buffer = bio_data(bio);    /* see ->buffer comment above */
-       req->bio = req->biotail = bio;
        req->ioprio = bio_prio(bio);
-       req->rq_disk = bio->bi_bdev->bd_disk;
        req->start_time = jiffies;
+       blk_rq_bio_prep(req->q, req, bio);
 }
 
 static int __make_request(struct request_queue *q, struct bio *bio)
@@ -3038,7 +3040,7 @@ out:
        return 0;
 
 end_io:
-       bio_endio(bio, nr_sectors << 9, err);
+       bio_endio(bio, err);
        return 0;
 }
 
@@ -3185,7 +3187,7 @@ static inline void __generic_make_request(struct bio *bio)
                                bdevname(bio->bi_bdev, b),
                                (long long) bio->bi_sector);
 end_io:
-                       bio_endio(bio, bio->bi_size, -EIO);
+                       bio_endio(bio, -EIO);
                        break;
                }
 
@@ -3329,48 +3331,6 @@ void submit_bio(int rw, struct bio *bio)
 
 EXPORT_SYMBOL(submit_bio);
 
-static void blk_recalc_rq_segments(struct request *rq)
-{
-       struct bio *bio, *prevbio = NULL;
-       int nr_phys_segs, nr_hw_segs;
-       unsigned int phys_size, hw_size;
-       struct request_queue *q = rq->q;
-
-       if (!rq->bio)
-               return;
-
-       phys_size = hw_size = nr_phys_segs = nr_hw_segs = 0;
-       rq_for_each_bio(bio, rq) {
-               /* Force bio hw/phys segs to be recalculated. */
-               bio->bi_flags &= ~(1 << BIO_SEG_VALID);
-
-               nr_phys_segs += bio_phys_segments(q, bio);
-               nr_hw_segs += bio_hw_segments(q, bio);
-               if (prevbio) {
-                       int pseg = phys_size + prevbio->bi_size + bio->bi_size;
-                       int hseg = hw_size + prevbio->bi_size + bio->bi_size;
-
-                       if (blk_phys_contig_segment(q, prevbio, bio) &&
-                           pseg <= q->max_segment_size) {
-                               nr_phys_segs--;
-                               phys_size += prevbio->bi_size + bio->bi_size;
-                       } else
-                               phys_size = 0;
-
-                       if (blk_hw_contig_segment(q, prevbio, bio) &&
-                           hseg <= q->max_segment_size) {
-                               nr_hw_segs--;
-                               hw_size += prevbio->bi_size + bio->bi_size;
-                       } else
-                               hw_size = 0;
-               }
-               prevbio = bio;
-       }
-
-       rq->nr_phys_segments = nr_phys_segs;
-       rq->nr_hw_segments = nr_hw_segs;
-}
-
 static void blk_recalc_rq_sectors(struct request *rq, int nsect)
 {
        if (blk_fs_request(rq)) {
@@ -3442,8 +3402,7 @@ static int __end_that_request_first(struct request *req, int uptodate,
                if (nr_bytes >= bio->bi_size) {
                        req->bio = bio->bi_next;
                        nbytes = bio->bi_size;
-                       if (!ordered_bio_endio(req, bio, nbytes, error))
-                               bio_endio(bio, nbytes, error);
+                       req_bio_endio(req, bio, nbytes, error);
                        next_idx = 0;
                        bio_nbytes = 0;
                } else {
@@ -3498,8 +3457,7 @@ static int __end_that_request_first(struct request *req, int uptodate,
         * if the request wasn't completed, update state
         */
        if (bio_nbytes) {
-               if (!ordered_bio_endio(req, bio, bio_nbytes, error))
-                       bio_endio(bio, bio_nbytes, error);
+               req_bio_endio(req, bio, bio_nbytes, error);
                bio->bi_idx += next_idx;
                bio_iovec(bio)->bv_offset += nr_bytes;
                bio_iovec(bio)->bv_len -= nr_bytes;
@@ -3574,7 +3532,7 @@ static void blk_done_softirq(struct softirq_action *h)
        }
 }
 
-static int blk_cpu_notify(struct notifier_block *self, unsigned long action,
+static int __cpuinit blk_cpu_notify(struct notifier_block *self, unsigned long action,
                          void *hcpu)
 {
        /*
@@ -3595,7 +3553,7 @@ static int blk_cpu_notify(struct notifier_block *self, unsigned long action,
 }
 
 
-static struct notifier_block __devinitdata blk_cpu_notifier = {
+static struct notifier_block blk_cpu_notifier __cpuinitdata = {
        .notifier_call  = blk_cpu_notify,
 };
 
@@ -3680,8 +3638,8 @@ void end_request(struct request *req, int uptodate)
 
 EXPORT_SYMBOL(end_request);
 
-void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
-                    struct bio *bio)
+static void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
+                           struct bio *bio)
 {
        /* first two bits are identical in rq->cmd_flags and bio->bi_rw */
        rq->cmd_flags |= (bio->bi_rw & 3);
@@ -3695,9 +3653,10 @@ void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
        rq->data_len = bio->bi_size;
 
        rq->bio = rq->biotail = bio;
-}
 
-EXPORT_SYMBOL(blk_rq_bio_prep);
+       if (bio->bi_bdev)
+               rq->rq_disk = bio->bi_bdev->bd_disk;
+}
 
 int kblockd_schedule_work(struct work_struct *work)
 {
@@ -3969,7 +3928,6 @@ queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
                        max_hw_sectors_kb = q->max_hw_sectors >> 1,
                        page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
        ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
-       int ra_kb;
 
        if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb)
                return -EINVAL;
@@ -3978,14 +3936,6 @@ queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
         * values synchronously:
         */
        spin_lock_irq(q->queue_lock);
-       /*
-        * Trim readahead window as well, if necessary:
-        */
-       ra_kb = q->backing_dev_info.ra_pages << (PAGE_CACHE_SHIFT - 10);
-       if (ra_kb > max_sectors_kb)
-               q->backing_dev_info.ra_pages =
-                               max_sectors_kb >> (PAGE_CACHE_SHIFT - 10);
-
        q->max_sectors = max_sectors_kb << 1;
        spin_unlock_irq(q->queue_lock);