9 files changed, 120 insertions, 72 deletions

diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
index 18af6f48781a..1431a6965017 100644
--- a/fs/btrfs/check-integrity.c
+++ b/fs/btrfs/check-integrity.c
@@ -1700,7 +1700,7 @@ static int btrfsic_read_block(struct btrfsic_state *state,
                 unsigned int j;
                 DECLARE_COMPLETION_ONSTACK(complete);
 
-                bio = bio_alloc(GFP_NOFS, num_pages - i);
+                bio = btrfs_io_bio_alloc(GFP_NOFS, num_pages - i);
                 if (!bio) {
                         printk(KERN_INFO
                                "btrfsic: bio_alloc() for %u pages failed!\n",
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 4bdb0528688a..e7b3cb5286a5 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3130,7 +3130,7 @@ static int write_dev_flush(struct btrfs_device *device, int wait)
          * caller
          */
         device->flush_bio = NULL;
-        bio = bio_alloc(GFP_NOFS, 0);
+        bio = btrfs_io_bio_alloc(GFP_NOFS, 0);
         if (!bio)
                 return -ENOMEM;
 
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index ca4355ddea06..b306b3a88fc7 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -23,6 +23,7 @@
 
 static struct kmem_cache *extent_state_cache;
 static struct kmem_cache *extent_buffer_cache;
+static struct bio_set *btrfs_bioset;
 
 #ifdef CONFIG_BTRFS_DEBUG
 static LIST_HEAD(buffers);
@@ -125,10 +126,20 @@ int __init extent_io_init(void)
                         SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
         if (!extent_buffer_cache)
                 goto free_state_cache;
+
+        btrfs_bioset = bioset_create(BIO_POOL_SIZE,
+                                     offsetof(struct btrfs_io_bio, bio));
+        if (!btrfs_bioset)
+                goto free_buffer_cache;
         return 0;
 
+free_buffer_cache:
+        kmem_cache_destroy(extent_buffer_cache);
+        extent_buffer_cache = NULL;
+
 free_state_cache:
         kmem_cache_destroy(extent_state_cache);
+        extent_state_cache = NULL;
         return -ENOMEM;
 }
 
@@ -145,6 +156,8 @@ void extent_io_exit(void)
                 kmem_cache_destroy(extent_state_cache);
         if (extent_buffer_cache)
                 kmem_cache_destroy(extent_buffer_cache);
+        if (btrfs_bioset)
+                bioset_free(btrfs_bioset);
 }
 
 void extent_io_tree_init(struct extent_io_tree *tree,
@@ -2024,7 +2037,7 @@ int repair_io_failure(struct btrfs_fs_info *fs_info, u64 start,
         if (btrfs_is_parity_mirror(map_tree, logical, length, mirror_num))
                 return 0;
 
-        bio = bio_alloc(GFP_NOFS, 1);
+        bio = btrfs_io_bio_alloc(GFP_NOFS, 1);
         if (!bio)
                 return -EIO;
         bio->bi_private = &compl;
@@ -2314,7 +2327,7 @@ static int bio_readpage_error(struct bio *failed_bio, struct page *page,
                 return -EIO;
         }
 
-        bio = bio_alloc(GFP_NOFS, 1);
+        bio = btrfs_io_bio_alloc(GFP_NOFS, 1);
         if (!bio) {
                 free_io_failure(inode, failrec, 0);
                 return -EIO;
@@ -2436,10 +2449,11 @@ static void end_bio_extent_readpage(struct bio *bio, int err)
                 struct page *page = bvec->bv_page;
                 struct extent_state *cached = NULL;
                 struct extent_state *state;
+                struct btrfs_io_bio *io_bio = btrfs_io_bio(bio);
 
                 pr_debug("end_bio_extent_readpage: bi_sector=%llu, err=%d, "
-                         "mirror=%ld\n", (u64)bio->bi_sector, err,
-                         (long int)bio->bi_bdev);
+                         "mirror=%lu\n", (u64)bio->bi_sector, err,
+                         io_bio->mirror_num);
                 tree = &BTRFS_I(page->mapping->host)->io_tree;
 
                 /* We always issue full-page reads, but if some block
@@ -2470,7 +2484,7 @@ static void end_bio_extent_readpage(struct bio *bio, int err)
                 }
                 spin_unlock(&tree->lock);
 
-                mirror = (int)(unsigned long)bio->bi_bdev;
+                mirror = io_bio->mirror_num;
                 if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) {
                         ret = tree->ops->readpage_end_io_hook(page, start, end,
                                                               state, mirror);
@@ -2525,17 +2539,23 @@ static void end_bio_extent_readpage(struct bio *bio, int err)
         bio_put(bio);
 }
 
+/*
+ * this allocates from the btrfs_bioset.  We're returning a bio right now
+ * but you can call btrfs_io_bio for the appropriate container_of magic
+ */
 struct bio *
 btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
                 gfp_t gfp_flags)
 {
         struct bio *bio;
 
-        bio = bio_alloc(gfp_flags, nr_vecs);
+        bio = bio_alloc_bioset(gfp_flags, nr_vecs, btrfs_bioset);
 
         if (bio == NULL && (current->flags & PF_MEMALLOC)) {
-                while (!bio && (nr_vecs /= 2))
-                        bio = bio_alloc(gfp_flags, nr_vecs);
+                while (!bio && (nr_vecs /= 2)) {
+                        bio = bio_alloc_bioset(gfp_flags,
+                                               nr_vecs, btrfs_bioset);
+                }
         }
 
         if (bio) {
@@ -2546,6 +2566,19 @@ btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
         return bio;
 }
 
+struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask)
+{
+        return bio_clone_bioset(bio, gfp_mask, btrfs_bioset);
+}
+
+
+/* this also allocates from the btrfs_bioset */
+struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
+{
+        return bio_alloc_bioset(gfp_mask, nr_iovecs, btrfs_bioset);
+}
+
+
 static int __must_check submit_one_bio(int rw, struct bio *bio,
                                        int mirror_num, unsigned long bio_flags)
 {
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index a2c03a175009..41fb81e7ec53 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -336,6 +336,8 @@ int extent_clear_unlock_delalloc(struct inode *inode,
 struct bio *
 btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
                 gfp_t gfp_flags);
+struct bio *btrfs_io_bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs);
+struct bio *btrfs_bio_clone(struct bio *bio, gfp_t gfp_mask);
 
 struct btrfs_fs_info;
 
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 19eef3e852b0..23c596cd1b98 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -6931,7 +6931,11 @@ struct btrfs_dio_private {
         /* IO errors */
         int errors;
 
+        /* orig_bio is our btrfs_io_bio */
         struct bio *orig_bio;
+
+        /* dio_bio came from fs/direct-io.c */
+        struct bio *dio_bio;
 };
 
 static void btrfs_endio_direct_read(struct bio *bio, int err)
@@ -6941,6 +6945,7 @@ static void btrfs_endio_direct_read(struct bio *bio, int err)
         struct bio_vec *bvec = bio->bi_io_vec;
         struct inode *inode = dip->inode;
         struct btrfs_root *root = BTRFS_I(inode)->root;
+        struct bio *dio_bio;
         u64 start;
 
         start = dip->logical_offset;
@@ -6980,14 +6985,15 @@ failed:
 
         unlock_extent(&BTRFS_I(inode)->io_tree, dip->logical_offset,
                       dip->logical_offset + dip->bytes - 1);
-        bio->bi_private = dip->private;
+        dio_bio = dip->dio_bio;
 
         kfree(dip);
 
         /* If we had a csum failure make sure to clear the uptodate flag */
         if (err)
-                clear_bit(BIO_UPTODATE, &bio->bi_flags);
-        dio_end_io(bio, err);
+                clear_bit(BIO_UPTODATE, &dio_bio->bi_flags);
+        dio_end_io(dio_bio, err);
+        bio_put(bio);
 }
 
 static void btrfs_endio_direct_write(struct bio *bio, int err)
@@ -6998,6 +7004,7 @@ static void btrfs_endio_direct_write(struct bio *bio, int err)
         struct btrfs_ordered_extent *ordered = NULL;
         u64 ordered_offset = dip->logical_offset;
         u64 ordered_bytes = dip->bytes;
+        struct bio *dio_bio;
         int ret;
 
         if (err)
@@ -7025,14 +7032,15 @@ out_test:
                 goto again;
         }
 out_done:
-        bio->bi_private = dip->private;
+        dio_bio = dip->dio_bio;
 
         kfree(dip);
 
         /* If we had an error make sure to clear the uptodate flag */
         if (err)
-                clear_bit(BIO_UPTODATE, &bio->bi_flags);
-        dio_end_io(bio, err);
+                clear_bit(BIO_UPTODATE, &dio_bio->bi_flags);
+        dio_end_io(dio_bio, err);
+        bio_put(bio);
 }
 
 static int __btrfs_submit_bio_start_direct_io(struct inode *inode, int rw,
@@ -7068,10 +7076,10 @@ static void btrfs_end_dio_bio(struct bio *bio, int err)
         if (!atomic_dec_and_test(&dip->pending_bios))
                 goto out;
 
-        if (dip->errors)
+        if (dip->errors) {
                 bio_io_error(dip->orig_bio);
-        else {
-                set_bit(BIO_UPTODATE, &dip->orig_bio->bi_flags);
+        } else {
+                set_bit(BIO_UPTODATE, &dip->dio_bio->bi_flags);
                 bio_endio(dip->orig_bio, 0);
         }
 out:
@@ -7246,25 +7254,34 @@ out_err:
         return 0;
 }
 
-static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode,
-                                loff_t file_offset)
+static void btrfs_submit_direct(int rw, struct bio *dio_bio,
+                                struct inode *inode, loff_t file_offset)
 {
         struct btrfs_root *root = BTRFS_I(inode)->root;
         struct btrfs_dio_private *dip;
-        struct bio_vec *bvec = bio->bi_io_vec;
+        struct bio_vec *bvec = dio_bio->bi_io_vec;
+        struct bio *io_bio;
         int skip_sum;
         int write = rw & REQ_WRITE;
         int ret = 0;
 
         skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
 
+        io_bio = btrfs_bio_clone(dio_bio, GFP_NOFS);
+
+        if (!io_bio) {
+                ret = -ENOMEM;
+                goto free_ordered;
+        }
+
         dip = kmalloc(sizeof(*dip), GFP_NOFS);
         if (!dip) {
                 ret = -ENOMEM;
-                goto free_ordered;
+                goto free_io_bio;
         }
 
-        dip->private = bio->bi_private;
+        dip->private = dio_bio->bi_private;
+        io_bio->bi_private = dio_bio->bi_private;
         dip->inode = inode;
         dip->logical_offset = file_offset;
 
@@ -7272,22 +7289,27 @@ static void btrfs_submit_direct(int rw, struct bio *bio, struct inode *inode,
         do {
                 dip->bytes += bvec->bv_len;
                 bvec++;
-        } while (bvec <= (bio->bi_io_vec + bio->bi_vcnt - 1));
+        } while (bvec <= (dio_bio->bi_io_vec + dio_bio->bi_vcnt - 1));
 
-        dip->disk_bytenr = (u64)bio->bi_sector << 9;
-        bio->bi_private = dip;
+        dip->disk_bytenr = (u64)dio_bio->bi_sector << 9;
+        io_bio->bi_private = dip;
         dip->errors = 0;
-        dip->orig_bio = bio;
+        dip->orig_bio = io_bio;
+        dip->dio_bio = dio_bio;
         atomic_set(&dip->pending_bios, 0);
 
         if (write)
-                bio->bi_end_io = btrfs_endio_direct_write;
+                io_bio->bi_end_io = btrfs_endio_direct_write;
         else
-                bio->bi_end_io = btrfs_endio_direct_read;
+                io_bio->bi_end_io = btrfs_endio_direct_read;
 
         ret = btrfs_submit_direct_hook(rw, dip, skip_sum);
         if (!ret)
                 return;
+
+free_io_bio:
+        bio_put(io_bio);
+
 free_ordered:
         /*
          * If this is a write, we need to clean up the reserved space and kill
@@ -7303,7 +7325,7 @@ free_ordered:
                 btrfs_put_ordered_extent(ordered);
                 btrfs_put_ordered_extent(ordered);
         }
-        bio_endio(bio, ret);
+        bio_endio(dio_bio, ret);
 }
 
 static ssize_t check_direct_IO(struct btrfs_root *root, int rw, struct kiocb *iocb,
diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index 0740621daf6c..0525e1389f5b 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -1050,7 +1050,7 @@ static int rbio_add_io_page(struct btrfs_raid_bio *rbio,
         }
 
         /* put a new bio on the list */
-        bio = bio_alloc(GFP_NOFS, bio_max_len >> PAGE_SHIFT?:1);
+        bio = btrfs_io_bio_alloc(GFP_NOFS, bio_max_len >> PAGE_SHIFT?:1);
         if (!bio)
                 return -ENOMEM;
 
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index f489e24659a4..79bd479317cb 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -1296,7 +1296,7 @@ static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
                 }
 
                 WARN_ON(!page->page);
-                bio = bio_alloc(GFP_NOFS, 1);
+                bio = btrfs_io_bio_alloc(GFP_NOFS, 1);
                 if (!bio) {
                         page->io_error = 1;
                         sblock->no_io_error_seen = 0;
@@ -1431,7 +1431,7 @@ static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
                         return -EIO;
                 }
 
-                bio = bio_alloc(GFP_NOFS, 1);
+                bio = btrfs_io_bio_alloc(GFP_NOFS, 1);
                 if (!bio)
                         return -EIO;
                 bio->bi_bdev = page_bad->dev->bdev;
@@ -1522,7 +1522,7 @@ again:
                 sbio->dev = wr_ctx->tgtdev;
                 bio = sbio->bio;
                 if (!bio) {
-                        bio = bio_alloc(GFP_NOFS, wr_ctx->pages_per_wr_bio);
+                        bio = btrfs_io_bio_alloc(GFP_NOFS, wr_ctx->pages_per_wr_bio);
                         if (!bio) {
                                 mutex_unlock(&wr_ctx->wr_lock);
                                 return -ENOMEM;
@@ -1930,7 +1930,7 @@ again:
                 sbio->dev = spage->dev;
                 bio = sbio->bio;
                 if (!bio) {
-                        bio = bio_alloc(GFP_NOFS, sctx->pages_per_rd_bio);
+                        bio = btrfs_io_bio_alloc(GFP_NOFS, sctx->pages_per_rd_bio);
                         if (!bio)
                                 return -ENOMEM;
                         sbio->bio = bio;
@@ -3307,7 +3307,7 @@ static int write_page_nocow(struct scrub_ctx *sctx,
                         "btrfs: scrub write_page_nocow(bdev == NULL) is unexpected!\n");
                 return -EIO;
         }
-        bio = bio_alloc(GFP_NOFS, 1);
+        bio = btrfs_io_bio_alloc(GFP_NOFS, 1);
         if (!bio) {
                 spin_lock(&sctx->stat_lock);
                 sctx->stat.malloc_errors++;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 062e93069c5e..24940085cdac 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -5018,42 +5018,16 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
         return 0;
 }
 
-static void *merge_stripe_index_into_bio_private(void *bi_private,
-                                                 unsigned int stripe_index)
-{
-        /*
-         * with single, dup, RAID0, RAID1 and RAID10, stripe_index is
-         * at most 1.
-         * The alternative solution (instead of stealing bits from the
-         * pointer) would be to allocate an intermediate structure
-         * that contains the old private pointer plus the stripe_index.
-         */
-        BUG_ON((((uintptr_t)bi_private) & 3) != 0);
-        BUG_ON(stripe_index > 3);
-        return (void *)(((uintptr_t)bi_private) | stripe_index);
-}
-
-static struct btrfs_bio *extract_bbio_from_bio_private(void *bi_private)
-{
-        return (struct btrfs_bio *)(((uintptr_t)bi_private) & ~((uintptr_t)3));
-}
-
-static unsigned int extract_stripe_index_from_bio_private(void *bi_private)
-{
-        return (unsigned int)((uintptr_t)bi_private) & 3;
-}
-
 static void btrfs_end_bio(struct bio *bio, int err)
 {
-        struct btrfs_bio *bbio = extract_bbio_from_bio_private(bio->bi_private);
+        struct btrfs_bio *bbio = bio->bi_private;
         int is_orig_bio = 0;
 
         if (err) {
                 atomic_inc(&bbio->error);
                 if (err == -EIO || err == -EREMOTEIO) {
                         unsigned int stripe_index =
-                                extract_stripe_index_from_bio_private(
-                                        bio->bi_private);
+                                btrfs_io_bio(bio)->stripe_index;
                         struct btrfs_device *dev;
 
                         BUG_ON(stripe_index >= bbio->num_stripes);
@@ -5083,8 +5057,7 @@ static void btrfs_end_bio(struct bio *bio, int err)
                 }
                 bio->bi_private = bbio->private;
                 bio->bi_end_io = bbio->end_io;
-                bio->bi_bdev = (struct block_device *)
-                                        (unsigned long)bbio->mirror_num;
+                btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
                 /* only send an error to the higher layers if it is
                  * beyond the tolerance of the btrfs bio
                  */
@@ -5210,8 +5183,7 @@ static void submit_stripe_bio(struct btrfs_root *root, struct btrfs_bio *bbio,
         struct btrfs_device *dev = bbio->stripes[dev_nr].dev;
 
         bio->bi_private = bbio;
-        bio->bi_private = merge_stripe_index_into_bio_private(
-                        bio->bi_private, (unsigned int)dev_nr);
+        btrfs_io_bio(bio)->stripe_index = dev_nr;
         bio->bi_end_io = btrfs_end_bio;
         bio->bi_sector = physical >> 9;
 #ifdef DEBUG
@@ -5272,8 +5244,7 @@ static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
         if (atomic_dec_and_test(&bbio->stripes_pending)) {
                 bio->bi_private = bbio->private;
                 bio->bi_end_io = bbio->end_io;
-                bio->bi_bdev = (struct block_device *)
-                        (unsigned long)bbio->mirror_num;
+                btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
                 bio->bi_sector = logical >> 9;
                 kfree(bbio);
                 bio_endio(bio, -EIO);
@@ -5351,7 +5322,7 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
                 }
 
                 if (dev_nr < total_devs - 1) {
-                        bio = bio_clone(first_bio, GFP_NOFS);
+                        bio = btrfs_bio_clone(first_bio, GFP_NOFS);
                         BUG_ON(!bio); /* -ENOMEM */
                 } else {
                         bio = first_bio;
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 845ccbb0d2e3..f6247e2a47f7 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -152,6 +152,26 @@ struct btrfs_fs_devices {
         int rotating;
 };
 
+/*
+ * we need the mirror number and stripe index to be passed around
+ * the call chain while we are processing end_io (especially errors).
+ * Really, what we need is a btrfs_bio structure that has this info
+ * and is properly sized with its stripe array, but we're not there
+ * quite yet.  We have our own btrfs bioset, and all of the bios
+ * we allocate are actually btrfs_io_bios.  We'll cram as much of
+ * struct btrfs_bio as we can into this over time.
+ */
+struct btrfs_io_bio {
+        unsigned long mirror_num;
+        unsigned long stripe_index;
+        struct bio bio;
+};
+
+static inline struct btrfs_io_bio *btrfs_io_bio(struct bio *bio)
+{
+        return container_of(bio, struct btrfs_io_bio, bio);
+}
+
 struct btrfs_bio_stripe {
         struct btrfs_device *dev;
         u64 physical;