Merge branch 'lzo-support' of git://repo.or.cz/linux-btrfs-devel into btrfs-38

20 files changed, 1051 insertions, 385 deletions

diff --git a/fs/btrfs/Kconfig b/fs/btrfs/Kconfig
index 7bb3c020e570..ecb9fd3be143 100644
--- a/fs/btrfs/Kconfig
+++ b/fs/btrfs/Kconfig
@@ -4,6 +4,8 @@ config BTRFS_FS
         select LIBCRC32C
         select ZLIB_INFLATE
         select ZLIB_DEFLATE
+        select LZO_COMPRESS
+        select LZO_DECOMPRESS
         help
           Btrfs is a new filesystem with extents, writable snapshotting,
           support for multiple devices and many more features.
diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index a35eb36b32fd..31610ea73aec 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -6,5 +6,5 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
            transaction.o inode.o file.o tree-defrag.o \
            extent_map.o sysfs.o struct-funcs.o xattr.o ordered-data.o \
            extent_io.o volumes.o async-thread.o ioctl.o locking.o orphan.o \
-           export.o tree-log.o acl.o free-space-cache.o zlib.o \
+           export.o tree-log.o acl.o free-space-cache.o zlib.o lzo.o \
            compression.o delayed-ref.o relocation.o
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index 6ad63f17eca0..ccc991c542df 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -157,7 +157,7 @@ struct btrfs_inode {
         /*
          * always compress this one file
          */
-        unsigned force_compress:1;
+        unsigned force_compress:4;
 
         struct inode vfs_inode;
 };
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index b50bc4bd5c56..f745287fbf2e 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -62,6 +62,9 @@ struct compressed_bio {
         /* number of bytes on disk */
         unsigned long compressed_len;
 
+        /* the compression algorithm for this bio */
+        int compress_type;
+
         /* number of compressed pages in the array */
         unsigned long nr_pages;
 
@@ -173,11 +176,12 @@ static void end_compressed_bio_read(struct bio *bio, int err)
         /* ok, we're the last bio for this extent, lets start
          * the decompression.
          */
-        ret = btrfs_zlib_decompress_biovec(cb->compressed_pages,
-                                        cb->start,
-                                        cb->orig_bio->bi_io_vec,
-                                        cb->orig_bio->bi_vcnt,
-                                        cb->compressed_len);
+        ret = btrfs_decompress_biovec(cb->compress_type,
+                                      cb->compressed_pages,
+                                      cb->start,
+                                      cb->orig_bio->bi_io_vec,
+                                      cb->orig_bio->bi_vcnt,
+                                      cb->compressed_len);
 csum_failed:
         if (ret)
                 cb->errors = 1;
@@ -588,6 +592,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 
         cb->len = uncompressed_len;
         cb->compressed_len = compressed_len;
+        cb->compress_type = extent_compress_type(bio_flags);
         cb->orig_bio = bio;
 
         nr_pages = (compressed_len + PAGE_CACHE_SIZE - 1) /
@@ -677,3 +682,317 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
         bio_put(comp_bio);
         return 0;
 }
+
+static struct list_head comp_idle_workspace[BTRFS_COMPRESS_TYPES];
+static spinlock_t comp_workspace_lock[BTRFS_COMPRESS_TYPES];
+static int comp_num_workspace[BTRFS_COMPRESS_TYPES];
+static atomic_t comp_alloc_workspace[BTRFS_COMPRESS_TYPES];
+static wait_queue_head_t comp_workspace_wait[BTRFS_COMPRESS_TYPES];
+
+struct btrfs_compress_op *btrfs_compress_op[] = {
+        &btrfs_zlib_compress,
+        &btrfs_lzo_compress,
+};
+
+int __init btrfs_init_compress(void)
+{
+        int i;
+
+        for (i = 0; i < BTRFS_COMPRESS_TYPES; i++) {
+                INIT_LIST_HEAD(&comp_idle_workspace[i]);
+                spin_lock_init(&comp_workspace_lock[i]);
+                atomic_set(&comp_alloc_workspace[i], 0);
+                init_waitqueue_head(&comp_workspace_wait[i]);
+        }
+        return 0;
+}
+
+/*
+ * this finds an available workspace or allocates a new one
+ * ERR_PTR is returned if things go bad.
+ */
+static struct list_head *find_workspace(int type)
+{
+        struct list_head *workspace;
+        int cpus = num_online_cpus();
+        int idx = type - 1;
+
+        struct list_head *idle_workspace        = &comp_idle_workspace[idx];
+        spinlock_t *workspace_lock              = &comp_workspace_lock[idx];
+        atomic_t *alloc_workspace               = &comp_alloc_workspace[idx];
+        wait_queue_head_t *workspace_wait       = &comp_workspace_wait[idx];
+        int *num_workspace                      = &comp_num_workspace[idx];
+again:
+        spin_lock(workspace_lock);
+        if (!list_empty(idle_workspace)) {
+                workspace = idle_workspace->next;
+                list_del(workspace);
+                (*num_workspace)--;
+                spin_unlock(workspace_lock);
+                return workspace;
+
+        }
+        if (atomic_read(alloc_workspace) > cpus) {
+                DEFINE_WAIT(wait);
+
+                spin_unlock(workspace_lock);
+                prepare_to_wait(workspace_wait, &wait, TASK_UNINTERRUPTIBLE);
+                if (atomic_read(alloc_workspace) > cpus && !*num_workspace)
+                        schedule();
+                finish_wait(workspace_wait, &wait);
+                goto again;
+        }
+        atomic_inc(alloc_workspace);
+        spin_unlock(workspace_lock);
+
+        workspace = btrfs_compress_op[idx]->alloc_workspace();
+        if (IS_ERR(workspace)) {
+                atomic_dec(alloc_workspace);
+                wake_up(workspace_wait);
+        }
+        return workspace;
+}
+
+/*
+ * put a workspace struct back on the list or free it if we have enough
+ * idle ones sitting around
+ */
+static void free_workspace(int type, struct list_head *workspace)
+{
+        int idx = type - 1;
+        struct list_head *idle_workspace        = &comp_idle_workspace[idx];
+        spinlock_t *workspace_lock              = &comp_workspace_lock[idx];
+        atomic_t *alloc_workspace               = &comp_alloc_workspace[idx];
+        wait_queue_head_t *workspace_wait       = &comp_workspace_wait[idx];
+        int *num_workspace                      = &comp_num_workspace[idx];
+
+        spin_lock(workspace_lock);
+        if (*num_workspace < num_online_cpus()) {
+                list_add_tail(workspace, idle_workspace);
+                (*num_workspace)++;
+                spin_unlock(workspace_lock);
+                goto wake;
+        }
+        spin_unlock(workspace_lock);
+
+        btrfs_compress_op[idx]->free_workspace(workspace);
+        atomic_dec(alloc_workspace);
+wake:
+        if (waitqueue_active(workspace_wait))
+                wake_up(workspace_wait);
+}
+
+/*
+ * cleanup function for module exit
+ */
+static void free_workspaces(void)
+{
+        struct list_head *workspace;
+        int i;
+
+        for (i = 0; i < BTRFS_COMPRESS_TYPES; i++) {
+                while (!list_empty(&comp_idle_workspace[i])) {
+                        workspace = comp_idle_workspace[i].next;
+                        list_del(workspace);
+                        btrfs_compress_op[i]->free_workspace(workspace);
+                        atomic_dec(&comp_alloc_workspace[i]);
+                }
+        }
+}
+
+/*
+ * given an address space and start/len, compress the bytes.
+ *
+ * pages are allocated to hold the compressed result and stored
+ * in 'pages'
+ *
+ * out_pages is used to return the number of pages allocated.  There
+ * may be pages allocated even if we return an error
+ *
+ * total_in is used to return the number of bytes actually read.  It
+ * may be smaller then len if we had to exit early because we
+ * ran out of room in the pages array or because we cross the
+ * max_out threshold.
+ *
+ * total_out is used to return the total number of compressed bytes
+ *
+ * max_out tells us the max number of bytes that we're allowed to
+ * stuff into pages
+ */
+int btrfs_compress_pages(int type, struct address_space *mapping,
+                         u64 start, unsigned long len,
+                         struct page **pages,
+                         unsigned long nr_dest_pages,
+                         unsigned long *out_pages,
+                         unsigned long *total_in,
+                         unsigned long *total_out,
+                         unsigned long max_out)
+{
+        struct list_head *workspace;
+        int ret;
+
+        workspace = find_workspace(type);
+        if (IS_ERR(workspace))
+                return -1;
+
+        ret = btrfs_compress_op[type-1]->compress_pages(workspace, mapping,
+                                                      start, len, pages,
+                                                      nr_dest_pages, out_pages,
+                                                      total_in, total_out,
+                                                      max_out);
+        free_workspace(type, workspace);
+        return ret;
+}
+
+/*
+ * pages_in is an array of pages with compressed data.
+ *
+ * disk_start is the starting logical offset of this array in the file
+ *
+ * bvec is a bio_vec of pages from the file that we want to decompress into
+ *
+ * vcnt is the count of pages in the biovec
+ *
+ * srclen is the number of bytes in pages_in
+ *
+ * The basic idea is that we have a bio that was created by readpages.
+ * The pages in the bio are for the uncompressed data, and they may not
+ * be contiguous.  They all correspond to the range of bytes covered by
+ * the compressed extent.
+ */
+int btrfs_decompress_biovec(int type, struct page **pages_in, u64 disk_start,
+                            struct bio_vec *bvec, int vcnt, size_t srclen)
+{
+        struct list_head *workspace;
+        int ret;
+
+        workspace = find_workspace(type);
+        if (IS_ERR(workspace))
+                return -ENOMEM;
+
+        ret = btrfs_compress_op[type-1]->decompress_biovec(workspace, pages_in,
+                                                         disk_start,
+                                                         bvec, vcnt, srclen);
+        free_workspace(type, workspace);
+        return ret;
+}
+
+/*
+ * a less complex decompression routine.  Our compressed data fits in a
+ * single page, and we want to read a single page out of it.
+ * start_byte tells us the offset into the compressed data we're interested in
+ */
+int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page,
+                     unsigned long start_byte, size_t srclen, size_t destlen)
+{
+        struct list_head *workspace;
+        int ret;
+
+        workspace = find_workspace(type);
+        if (IS_ERR(workspace))
+                return -ENOMEM;
+
+        ret = btrfs_compress_op[type-1]->decompress(workspace, data_in,
+                                                  dest_page, start_byte,
+                                                  srclen, destlen);
+
+        free_workspace(type, workspace);
+        return ret;
+}
+
+void __exit btrfs_exit_compress(void)
+{
+        free_workspaces();
+}
+
+/*
+ * Copy uncompressed data from working buffer to pages.
+ *
+ * buf_start is the byte offset we're of the start of our workspace buffer.
+ *
+ * total_out is the last byte of the buffer
+ */
+int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
+                              unsigned long total_out, u64 disk_start,
+                              struct bio_vec *bvec, int vcnt,
+                              unsigned long *page_index,
+                              unsigned long *pg_offset)
+{
+        unsigned long buf_offset;
+        unsigned long current_buf_start;
+        unsigned long start_byte;
+        unsigned long working_bytes = total_out - buf_start;
+        unsigned long bytes;
+        char *kaddr;
+        struct page *page_out = bvec[*page_index].bv_page;
+
+        /*
+         * start byte is the first byte of the page we're currently
+         * copying into relative to the start of the compressed data.
+         */
+        start_byte = page_offset(page_out) - disk_start;
+
+        /* we haven't yet hit data corresponding to this page */
+        if (total_out <= start_byte)
+                return 1;
+
+        /*
+         * the start of the data we care about is offset into
+         * the middle of our working buffer
+         */
+        if (total_out > start_byte && buf_start < start_byte) {
+                buf_offset = start_byte - buf_start;
+                working_bytes -= buf_offset;
+        } else {
+                buf_offset = 0;
+        }
+        current_buf_start = buf_start;
+
+        /* copy bytes from the working buffer into the pages */
+        while (working_bytes > 0) {
+                bytes = min(PAGE_CACHE_SIZE - *pg_offset,
+                            PAGE_CACHE_SIZE - buf_offset);
+                bytes = min(bytes, working_bytes);
+                kaddr = kmap_atomic(page_out, KM_USER0);
+                memcpy(kaddr + *pg_offset, buf + buf_offset, bytes);
+                kunmap_atomic(kaddr, KM_USER0);
+                flush_dcache_page(page_out);
+
+                *pg_offset += bytes;
+                buf_offset += bytes;
+                working_bytes -= bytes;
+                current_buf_start += bytes;
+
+                /* check if we need to pick another page */
+                if (*pg_offset == PAGE_CACHE_SIZE) {
+                        (*page_index)++;
+                        if (*page_index >= vcnt)
+                                return 0;
+
+                        page_out = bvec[*page_index].bv_page;
+                        *pg_offset = 0;
+                        start_byte = page_offset(page_out) - disk_start;
+
+                        /*
+                         * make sure our new page is covered by this
+                         * working buffer
+                         */
+                        if (total_out <= start_byte)
+                                return 1;
+
+                        /*
+                         * the next page in the biovec might not be adjacent
+                         * to the last page, but it might still be found
+                         * inside this working buffer. bump our offset pointer
+                         */
+                        if (total_out > start_byte &&
+                            current_buf_start < start_byte) {
+                                buf_offset = start_byte - buf_start;
+                                working_bytes = total_out - start_byte;
+                                current_buf_start = buf_start + buf_offset;
+                        }
+                }
+        }
+
+        return 1;
+}
diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h
index 421f5b4aa715..51000174b9d7 100644
--- a/fs/btrfs/compression.h
+++ b/fs/btrfs/compression.h
@@ -19,24 +19,27 @@
 #ifndef __BTRFS_COMPRESSION_
 #define __BTRFS_COMPRESSION_
 
-int btrfs_zlib_decompress(unsigned char *data_in,
-                          struct page *dest_page,
-                          unsigned long start_byte,
-                          size_t srclen, size_t destlen);
-int btrfs_zlib_compress_pages(struct address_space *mapping,
-                              u64 start, unsigned long len,
-                              struct page **pages,
-                              unsigned long nr_dest_pages,
-                              unsigned long *out_pages,
-                              unsigned long *total_in,
-                              unsigned long *total_out,
-                              unsigned long max_out);
-int btrfs_zlib_decompress_biovec(struct page **pages_in,
-                              u64 disk_start,
-                              struct bio_vec *bvec,
-                              int vcnt,
-                              size_t srclen);
-void btrfs_zlib_exit(void);
+int btrfs_init_compress(void);
+void btrfs_exit_compress(void);
+
+int btrfs_compress_pages(int type, struct address_space *mapping,
+                         u64 start, unsigned long len,
+                         struct page **pages,
+                         unsigned long nr_dest_pages,
+                         unsigned long *out_pages,
+                         unsigned long *total_in,
+                         unsigned long *total_out,
+                         unsigned long max_out);
+int btrfs_decompress_biovec(int type, struct page **pages_in, u64 disk_start,
+                            struct bio_vec *bvec, int vcnt, size_t srclen);
+int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page,
+                     unsigned long start_byte, size_t srclen, size_t destlen);
+int btrfs_decompress_buf2page(char *buf, unsigned long buf_start,
+                              unsigned long total_out, u64 disk_start,
+                              struct bio_vec *bvec, int vcnt,
+                              unsigned long *page_index,
+                              unsigned long *pg_offset);
+
 int btrfs_submit_compressed_write(struct inode *inode, u64 start,
                                   unsigned long len, u64 disk_start,
                                   unsigned long compressed_len,
@@ -44,4 +47,37 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
                                   unsigned long nr_pages);
 int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
                                  int mirror_num, unsigned long bio_flags);
+
+struct btrfs_compress_op {
+        struct list_head *(*alloc_workspace)(void);
+
+        void (*free_workspace)(struct list_head *workspace);
+
+        int (*compress_pages)(struct list_head *workspace,
+                              struct address_space *mapping,
+                              u64 start, unsigned long len,
+                              struct page **pages,
+                              unsigned long nr_dest_pages,
+                              unsigned long *out_pages,
+                              unsigned long *total_in,
+                              unsigned long *total_out,
+                              unsigned long max_out);
+
+        int (*decompress_biovec)(struct list_head *workspace,
+                                 struct page **pages_in,
+                                 u64 disk_start,
+                                 struct bio_vec *bvec,
+                                 int vcnt,
+                                 size_t srclen);
+
+        int (*decompress)(struct list_head *workspace,
+                          unsigned char *data_in,
+                          struct page *dest_page,
+                          unsigned long start_byte,
+                          size_t srclen, size_t destlen);
+};
+
+extern struct btrfs_compress_op btrfs_zlib_compress;
+extern struct btrfs_compress_op btrfs_lzo_compress;
+
 #endif
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 4403e5643d43..4acd4c611efa 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -398,13 +398,15 @@ struct btrfs_super_block {
 #define BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF    (1ULL << 0)
 #define BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL   (1ULL << 1)
 #define BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS     (1ULL << 2)
+#define BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO     (1ULL << 3)
 
 #define BTRFS_FEATURE_COMPAT_SUPP               0ULL
 #define BTRFS_FEATURE_COMPAT_RO_SUPP            0ULL
 #define BTRFS_FEATURE_INCOMPAT_SUPP                     \
         (BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF |         \
          BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL |        \
-         BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS)
+         BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS |          \
+         BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO)
 
 /*
  * A leaf is full of items. offset and size tell us where to find
@@ -551,9 +553,11 @@ struct btrfs_timespec {
 } __attribute__ ((__packed__));
 
 enum btrfs_compression_type {
-        BTRFS_COMPRESS_NONE = 0,
-        BTRFS_COMPRESS_ZLIB = 1,
-        BTRFS_COMPRESS_LAST = 2,
+        BTRFS_COMPRESS_NONE  = 0,
+        BTRFS_COMPRESS_ZLIB  = 1,
+        BTRFS_COMPRESS_LZO   = 2,
+        BTRFS_COMPRESS_TYPES = 2,
+        BTRFS_COMPRESS_LAST  = 3,
 };
 
 struct btrfs_inode_item {
@@ -897,7 +901,8 @@ struct btrfs_fs_info {
          */
         u64 last_trans_log_full_commit;
         u64 open_ioctl_trans;
-        unsigned long mount_opt;
+        unsigned long mount_opt:20;
+        unsigned long compress_type:4;
         u64 max_inline;
         u64 alloc_start;
         struct btrfs_transaction *running_transaction;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index a5d2249e6da5..f88eb2ce7919 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1744,10 +1744,10 @@ struct btrfs_root *open_ctree(struct super_block *sb,
         }
 
         features = btrfs_super_incompat_flags(disk_super);
-        if (!(features & BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF)) {
-                features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
-                btrfs_set_super_incompat_flags(disk_super, features);
-        }
+        features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
+        if (tree_root->fs_info->compress_type & BTRFS_COMPRESS_LZO)
+                features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
+        btrfs_set_super_incompat_flags(disk_super, features);
 
         features = btrfs_super_compat_ro_flags(disk_super) &
                 ~BTRFS_FEATURE_COMPAT_RO_SUPP;
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 5e7a94d7da89..f1d198128959 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2028,8 +2028,11 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
                 BUG_ON(extent_map_end(em) <= cur);
                 BUG_ON(end < cur);
 
-                if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
+                if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
                         this_bio_flag = EXTENT_BIO_COMPRESSED;
+                        extent_set_compress_type(&this_bio_flag,
+                                                 em->compress_type);
+                }
 
                 iosize = min(extent_map_end(em) - cur, end - cur + 1);
                 cur_end = min(extent_map_end(em) - 1, end);
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 4183c8178f01..7083cfafd061 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -20,8 +20,12 @@
 #define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
 #define EXTENT_CTLBITS (EXTENT_DO_ACCOUNTING | EXTENT_FIRST_DELALLOC)
 
-/* flags for bio submission */
+/*
+ * flags for bio submission. The high bits indicate the compression
+ * type for this bio
+ */
 #define EXTENT_BIO_COMPRESSED 1
+#define EXTENT_BIO_FLAG_SHIFT 16
 
 /* these are bit numbers for test/set bit */
 #define EXTENT_BUFFER_UPTODATE 0
@@ -135,6 +139,17 @@ struct extent_buffer {
         wait_queue_head_t lock_wq;
 };
 
+static inline void extent_set_compress_type(unsigned long *bio_flags,
+                                            int compress_type)
+{
+        *bio_flags |= compress_type << EXTENT_BIO_FLAG_SHIFT;
+}
+
+static inline int extent_compress_type(unsigned long bio_flags)
+{
+        return bio_flags >> EXTENT_BIO_FLAG_SHIFT;
+}
+
 struct extent_map_tree;
 
 static inline struct extent_state *extent_state_next(struct extent_state *state)
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 23cb8da3ff66..b0e1fce12530 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -3,6 +3,7 @@
 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <linux/hardirq.h>
+#include "ctree.h"
 #include "extent_map.h"
 
 
@@ -54,6 +55,7 @@ struct extent_map *alloc_extent_map(gfp_t mask)
                 return em;
         em->in_tree = 0;
         em->flags = 0;
+        em->compress_type = BTRFS_COMPRESS_NONE;
         atomic_set(&em->refs, 1);
         return em;
 }
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index ab6d74b6e647..28b44dbd1e35 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -26,7 +26,8 @@ struct extent_map {
         unsigned long flags;
         struct block_device *bdev;
         atomic_t refs;
-        int in_tree;
+        unsigned int in_tree:1;
+        unsigned int compress_type:4;
 };
 
 struct extent_map_tree {
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 66836d85763b..05df688c96f4 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -224,6 +224,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
 
                         split->bdev = em->bdev;
                         split->flags = flags;
+                        split->compress_type = em->compress_type;
                         ret = add_extent_mapping(em_tree, split);
                         BUG_ON(ret);
                         free_extent_map(split);
@@ -238,6 +239,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
                         split->len = em->start + em->len - (start + len);
                         split->bdev = em->bdev;
                         split->flags = flags;
+                        split->compress_type = em->compress_type;
 
                         if (compressed) {
                                 split->block_len = em->block_len;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 956f1eb913b1..1562765c8e6a 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -122,10 +122,10 @@ static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
         size_t cur_size = size;
         size_t datasize;
         unsigned long offset;
-        int use_compress = 0;
+        int compress_type = BTRFS_COMPRESS_NONE;
 
         if (compressed_size && compressed_pages) {
-                use_compress = 1;
+                compress_type = root->fs_info->compress_type;
                 cur_size = compressed_size;
         }
 
@@ -159,7 +159,7 @@ static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
         btrfs_set_file_extent_ram_bytes(leaf, ei, size);
         ptr = btrfs_file_extent_inline_start(ei);
 
-        if (use_compress) {
+        if (compress_type != BTRFS_COMPRESS_NONE) {
                 struct page *cpage;
                 int i = 0;
                 while (compressed_size > 0) {
@@ -176,7 +176,7 @@ static noinline int insert_inline_extent(struct btrfs_trans_handle *trans,
                         compressed_size -= cur_size;
                 }
                 btrfs_set_file_extent_compression(leaf, ei,
-                                                  BTRFS_COMPRESS_ZLIB);
+                                                  compress_type);
         } else {
                 page = find_get_page(inode->i_mapping,
                                      start >> PAGE_CACHE_SHIFT);
@@ -263,6 +263,7 @@ struct async_extent {
         u64 compressed_size;
         struct page **pages;
         unsigned long nr_pages;
+        int compress_type;
         struct list_head list;
 };
 
@@ -280,7 +281,8 @@ static noinline int add_async_extent(struct async_cow *cow,
                                      u64 start, u64 ram_size,
                                      u64 compressed_size,
                                      struct page **pages,
-                                     unsigned long nr_pages)
+                                     unsigned long nr_pages,
+                                     int compress_type)
 {
         struct async_extent *async_extent;
 
@@ -290,6 +292,7 @@ static noinline int add_async_extent(struct async_cow *cow,
         async_extent->compressed_size = compressed_size;
         async_extent->pages = pages;
         async_extent->nr_pages = nr_pages;
+        async_extent->compress_type = compress_type;
         list_add_tail(&async_extent->list, &cow->extents);
         return 0;
 }
@@ -332,6 +335,7 @@ static noinline int compress_file_range(struct inode *inode,
         unsigned long max_uncompressed = 128 * 1024;
         int i;
         int will_compress;
+        int compress_type = root->fs_info->compress_type;
 
         actual_end = min_t(u64, isize, end + 1);
 again:
@@ -381,12 +385,16 @@ again:
                 WARN_ON(pages);
                 pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
 
-                ret = btrfs_zlib_compress_pages(inode->i_mapping, start,
-                                                total_compressed, pages,
-                                                nr_pages, &nr_pages_ret,
-                                                &total_in,
-                                                &total_compressed,
-                                                max_compressed);
+                if (BTRFS_I(inode)->force_compress)
+                        compress_type = BTRFS_I(inode)->force_compress;
+
+                ret = btrfs_compress_pages(compress_type,
+                                           inode->i_mapping, start,
+                                           total_compressed, pages,
+                                           nr_pages, &nr_pages_ret,
+                                           &total_in,
+                                           &total_compressed,
+                                           max_compressed);
 
                 if (!ret) {
                         unsigned long offset = total_compressed &
@@ -493,7 +501,8 @@ again:
                  * and will submit them to the elevator.
                  */
                 add_async_extent(async_cow, start, num_bytes,
-                                 total_compressed, pages, nr_pages_ret);
+                                 total_compressed, pages, nr_pages_ret,
+                                 compress_type);
 
                 if (start + num_bytes < end) {
                         start += num_bytes;
@@ -515,7 +524,8 @@ cleanup_and_bail_uncompressed:
                         __set_page_dirty_nobuffers(locked_page);
                         /* unlocked later on in the async handlers */
                 }
-                add_async_extent(async_cow, start, end - start + 1, 0, NULL, 0);
+                add_async_extent(async_cow, start, end - start + 1,
+                                 0, NULL, 0, BTRFS_COMPRESS_NONE);
                 *num_added += 1;
         }
 
@@ -640,6 +650,7 @@ retry:
                 em->block_start = ins.objectid;
                 em->block_len = ins.offset;
                 em->bdev = root->fs_info->fs_devices->latest_bdev;
+                em->compress_type = async_extent->compress_type;
                 set_bit(EXTENT_FLAG_PINNED, &em->flags);
                 set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
 
@@ -656,11 +667,13 @@ retry:
                                                 async_extent->ram_size - 1, 0);
                 }
 
-                ret = btrfs_add_ordered_extent(inode, async_extent->start,
-                                               ins.objectid,
-                                               async_extent->ram_size,
-                                               ins.offset,
-                                               BTRFS_ORDERED_COMPRESSED);
+                ret = btrfs_add_ordered_extent_compress(inode,
+                                                async_extent->start,
+                                                ins.objectid,
+                                                async_extent->ram_size,
+                                                ins.offset,
+                                                BTRFS_ORDERED_COMPRESSED,
+                                                async_extent->compress_type);
                 BUG_ON(ret);
 
                 /*
@@ -1670,7 +1683,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
         struct btrfs_ordered_extent *ordered_extent = NULL;
         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
         struct extent_state *cached_state = NULL;
-        int compressed = 0;
+        int compress_type = 0;
         int ret;
         bool nolock = false;
 
@@ -1711,9 +1724,9 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
         trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
         if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
-                compressed = 1;
+                compress_type = ordered_extent->compress_type;
         if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) {
-                BUG_ON(compressed);
+                BUG_ON(compress_type);
                 ret = btrfs_mark_extent_written(trans, inode,
                                                 ordered_extent->file_offset,
                                                 ordered_extent->file_offset +
@@ -1727,7 +1740,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
                                                 ordered_extent->disk_len,
                                                 ordered_extent->len,
                                                 ordered_extent->len,
-                                                compressed, 0, 0,
+                                                compress_type, 0, 0,
                                                 BTRFS_FILE_EXTENT_REG);
                 unpin_extent_cache(&BTRFS_I(inode)->extent_tree,
                                    ordered_extent->file_offset,
@@ -1829,6 +1842,8 @@ static int btrfs_io_failed_hook(struct bio *failed_bio,
                 if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
                         logical = em->block_start;
                         failrec->bio_flags = EXTENT_BIO_COMPRESSED;
+                        extent_set_compress_type(&failrec->bio_flags,
+                                                 em->compress_type);
                 }
                 failrec->logical = logical;
                 free_extent_map(em);
@@ -4934,8 +4949,10 @@ static noinline int uncompress_inline(struct btrfs_path *path,
         size_t max_size;
         unsigned long inline_size;
         unsigned long ptr;
+        int compress_type;
 
         WARN_ON(pg_offset != 0);
+        compress_type = btrfs_file_extent_compression(leaf, item);
         max_size = btrfs_file_extent_ram_bytes(leaf, item);
         inline_size = btrfs_file_extent_inline_item_len(leaf,
                                         btrfs_item_nr(leaf, path->slots[0]));
@@ -4945,8 +4962,8 @@ static noinline int uncompress_inline(struct btrfs_path *path,
         read_extent_buffer(leaf, tmp, ptr, inline_size);
 
         max_size = min_t(unsigned long, PAGE_CACHE_SIZE, max_size);
-        ret = btrfs_zlib_decompress(tmp, page, extent_offset,
-                                    inline_size, max_size);
+        ret = btrfs_decompress(compress_type, tmp, page,
+                               extent_offset, inline_size, max_size);
         if (ret) {
                 char *kaddr = kmap_atomic(page, KM_USER0);
                 unsigned long copy_size = min_t(u64,
@@ -4988,7 +5005,7 @@ struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
         struct btrfs_trans_handle *trans = NULL;
-        int compressed;
+        int compress_type;
 
 again:
         read_lock(&em_tree->lock);
@@ -5047,7 +5064,7 @@ again:
 
         found_type = btrfs_file_extent_type(leaf, item);
         extent_start = found_key.offset;
-        compressed = btrfs_file_extent_compression(leaf, item);
+        compress_type = btrfs_file_extent_compression(leaf, item);
         if (found_type == BTRFS_FILE_EXTENT_REG ||
             found_type == BTRFS_FILE_EXTENT_PREALLOC) {
                 extent_end = extent_start +
@@ -5093,8 +5110,9 @@ again:
                         em->block_start = EXTENT_MAP_HOLE;
                         goto insert;
                 }
-                if (compressed) {
+                if (compress_type != BTRFS_COMPRESS_NONE) {
                         set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
+                        em->compress_type = compress_type;
                         em->block_start = bytenr;
                         em->block_len = btrfs_file_extent_disk_num_bytes(leaf,
                                                                          item);
@@ -5128,12 +5146,14 @@ again:
                 em->len = (copy_size + root->sectorsize - 1) &
                         ~((u64)root->sectorsize - 1);
                 em->orig_start = EXTENT_MAP_INLINE;
-                if (compressed)
+                if (compress_type) {
                         set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
+                        em->compress_type = compress_type;
+                }
                 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
                 if (create == 0 && !PageUptodate(page)) {
-                        if (btrfs_file_extent_compression(leaf, item) ==
-                            BTRFS_COMPRESS_ZLIB) {
+                        if (btrfs_file_extent_compression(leaf, item) !=
+                            BTRFS_COMPRESS_NONE) {
                                 ret = uncompress_inline(path, inode, page,
                                                         pg_offset,
                                                         extent_offset, item);
@@ -6483,7 +6503,7 @@ struct inode *btrfs_alloc_inode(struct super_block *sb)
         ei->ordered_data_close = 0;
         ei->orphan_meta_reserved = 0;
         ei->dummy_inode = 0;
-        ei->force_compress = 0;
+        ei->force_compress = BTRFS_COMPRESS_NONE;
 
         inode = &ei->vfs_inode;
         extent_map_tree_init(&ei->extent_tree, GFP_NOFS);
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index ad1983524f97..a506a22b522a 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -643,9 +643,11 @@ static int btrfs_defrag_file(struct file *file,
         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
         struct btrfs_ordered_extent *ordered;
         struct page *page;
+        struct btrfs_super_block *disk_super;
         unsigned long last_index;
         unsigned long ra_pages = root->fs_info->bdi.ra_pages;
         unsigned long total_read = 0;
+        u64 features;
         u64 page_start;
         u64 page_end;
         u64 last_len = 0;
@@ -653,6 +655,14 @@ static int btrfs_defrag_file(struct file *file,
         u64 defrag_end = 0;
         unsigned long i;
         int ret;
+        int compress_type = BTRFS_COMPRESS_ZLIB;
+
+        if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
+                if (range->compress_type > BTRFS_COMPRESS_TYPES)
+                        return -EINVAL;
+                if (range->compress_type)
+                        compress_type = range->compress_type;
+        }
 
         if (inode->i_size == 0)
                 return 0;
@@ -688,7 +698,7 @@ static int btrfs_defrag_file(struct file *file,
                 total_read++;
                 mutex_lock(&inode->i_mutex);
                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
-                        BTRFS_I(inode)->force_compress = 1;
+                        BTRFS_I(inode)->force_compress = compress_type;
 
                 ret  = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
                 if (ret)
@@ -786,10 +796,17 @@ loop_unlock:
                 atomic_dec(&root->fs_info->async_submit_draining);
 
                 mutex_lock(&inode->i_mutex);
-                BTRFS_I(inode)->force_compress = 0;
+                BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
                 mutex_unlock(&inode->i_mutex);
         }
 
+        disk_super = &root->fs_info->super_copy;
+        features = btrfs_super_incompat_flags(disk_super);
+        if (range->compress_type == BTRFS_COMPRESS_LZO) {
+                features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
+                btrfs_set_super_incompat_flags(disk_super, features);
+        }
+
         return 0;
 
 err_reservations:
diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h
index 1223223351fa..8fb382167b13 100644
--- a/fs/btrfs/ioctl.h
+++ b/fs/btrfs/ioctl.h
@@ -134,8 +134,15 @@ struct btrfs_ioctl_defrag_range_args {
          */
         __u32 extent_thresh;
 
+        /*
+         * which compression method to use if turning on compression
+         * for this defrag operation.  If unspecified, zlib will
+         * be used
+         */
+        __u32 compress_type;
+
         /* spare for later */
-        __u32 unused[5];
+        __u32 unused[4];
 };
 
 struct btrfs_ioctl_space_info {
diff --git a/fs/btrfs/lzo.c b/fs/btrfs/lzo.c
new file mode 100644
index 000000000000..cc9b450399df
--- /dev/null
+++ b/fs/btrfs/lzo.c
@@ -0,0 +1,420 @@
+/*
+ * Copyright (C) 2008 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/pagemap.h>
+#include <linux/bio.h>
+#include <linux/lzo.h>
+#include "compression.h"
+
+#define LZO_LEN 4
+
+struct workspace {
+        void *mem;
+        void *buf;      /* where compressed data goes */
+        void *cbuf;     /* where decompressed data goes */
+        struct list_head list;
+};
+
+static void lzo_free_workspace(struct list_head *ws)
+{
+        struct workspace *workspace = list_entry(ws, struct workspace, list);
+
+        vfree(workspace->buf);
+        vfree(workspace->cbuf);
+        vfree(workspace->mem);
+        kfree(workspace);
+}
+
+static struct list_head *lzo_alloc_workspace(void)
+{
+        struct workspace *workspace;
+
+        workspace = kzalloc(sizeof(*workspace), GFP_NOFS);
+        if (!workspace)
+                return ERR_PTR(-ENOMEM);
+
+        workspace->mem = vmalloc(LZO1X_MEM_COMPRESS);
+        workspace->buf = vmalloc(lzo1x_worst_compress(PAGE_CACHE_SIZE));
+        workspace->cbuf = vmalloc(lzo1x_worst_compress(PAGE_CACHE_SIZE));
+        if (!workspace->mem || !workspace->buf || !workspace->cbuf)
+                goto fail;
+
+        INIT_LIST_HEAD(&workspace->list);
+
+        return &workspace->list;
+fail:
+        lzo_free_workspace(&workspace->list);
+        return ERR_PTR(-ENOMEM);
+}
+
+static inline void write_compress_length(char *buf, size_t len)
+{
+        __le32 dlen;
+
+        dlen = cpu_to_le32(len);
+        memcpy(buf, &dlen, LZO_LEN);
+}
+
+static inline size_t read_compress_length(char *buf)
+{
+        __le32 dlen;
+
+        memcpy(&dlen, buf, LZO_LEN);
+        return le32_to_cpu(dlen);
+}
+
+static int lzo_compress_pages(struct list_head *ws,
+                              struct address_space *mapping,
+                              u64 start, unsigned long len,
+                              struct page **pages,
+                              unsigned long nr_dest_pages,
+                              unsigned long *out_pages,
+                              unsigned long *total_in,
+                              unsigned long *total_out,
+                              unsigned long max_out)
+{
+        struct workspace *workspace = list_entry(ws, struct workspace, list);
+        int ret = 0;
+        char *data_in;
+        char *cpage_out;
+        int nr_pages = 0;
+        struct page *in_page = NULL;
+        struct page *out_page = NULL;
+        unsigned long bytes_left;
+
+        size_t in_len;
+        size_t out_len;
+        char *buf;
+        unsigned long tot_in = 0;
+        unsigned long tot_out = 0;
+        unsigned long pg_bytes_left;
+        unsigned long out_offset;
+        unsigned long bytes;
+
+        *out_pages = 0;
+        *total_out = 0;
+        *total_in = 0;
+
+        in_page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT);
+        data_in = kmap(in_page);
+
+        /*
+         * store the size of all chunks of compressed data in
+         * the first 4 bytes
+         */
+        out_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
+        if (out_page == NULL) {
+                ret = -ENOMEM;
+                goto out;
+        }
+        cpage_out = kmap(out_page);
+        out_offset = LZO_LEN;
+        tot_out = LZO_LEN;
+        pages[0] = out_page;
+        nr_pages = 1;
+        pg_bytes_left = PAGE_CACHE_SIZE - LZO_LEN;
+
+        /* compress at most one page of data each time */
+        in_len = min(len, PAGE_CACHE_SIZE);
+        while (tot_in < len) {
+                ret = lzo1x_1_compress(data_in, in_len, workspace->cbuf,
+                                       &out_len, workspace->mem);
+                if (ret != LZO_E_OK) {
+                        printk(KERN_DEBUG "btrfs deflate in loop returned %d\n",
+                               ret);
+                        ret = -1;
+                        goto out;
+                }
+
+                /* store the size of this chunk of compressed data */
+                write_compress_length(cpage_out + out_offset, out_len);
+                tot_out += LZO_LEN;
+                out_offset += LZO_LEN;
+                pg_bytes_left -= LZO_LEN;
+
+                tot_in += in_len;
+                tot_out += out_len;
+
+                /* copy bytes from the working buffer into the pages */
+                buf = workspace->cbuf;
+                while (out_len) {
+                        bytes = min_t(unsigned long, pg_bytes_left, out_len);
+
+                        memcpy(cpage_out + out_offset, buf, bytes);
+
+                        out_len -= bytes;
+                        pg_bytes_left -= bytes;
+                        buf += bytes;
+                        out_offset += bytes;
+
+                        /*
+                         * we need another page for writing out.
+                         *
+                         * Note if there's less than 4 bytes left, we just
+                         * skip to a new page.
+                         */
+                        if ((out_len == 0 && pg_bytes_left < LZO_LEN) ||
+                            pg_bytes_left == 0) {
+                                if (pg_bytes_left) {
+                                        memset(cpage_out + out_offset, 0,
+                                               pg_bytes_left);
+                                        tot_out += pg_bytes_left;
+                                }
+
+                                /* we're done, don't allocate new page */
+                                if (out_len == 0 && tot_in >= len)
+                                        break;
+
+                                kunmap(out_page);
+                                if (nr_pages == nr_dest_pages) {
+                                        out_page = NULL;
+                                        ret = -1;
+                                        goto out;
+                                }
+
+                                out_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
+                                if (out_page == NULL) {
+                                        ret = -ENOMEM;
+                                        goto out;
+                                }
+                                cpage_out = kmap(out_page);
+                                pages[nr_pages++] = out_page;
+
+                                pg_bytes_left = PAGE_CACHE_SIZE;
+                                out_offset = 0;
+                        }
+                }
+
+                /* we're making it bigger, give up */
+                if (tot_in > 8192 && tot_in < tot_out)
+                        goto out;
+
+                /* we're all done */
+                if (tot_in >= len)
+                        break;
+
+                if (tot_out > max_out)
+                        break;
+
+                bytes_left = len - tot_in;
+                kunmap(in_page);
+                page_cache_release(in_page);
+
+                start += PAGE_CACHE_SIZE;
+                in_page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT);
+                data_in = kmap(in_page);
+                in_len = min(bytes_left, PAGE_CACHE_SIZE);
+        }
+
+        if (tot_out > tot_in)
+                goto out;
+
+        /* store the size of all chunks of compressed data */
+        cpage_out = kmap(pages[0]);
+        write_compress_length(cpage_out, tot_out);
+
+        kunmap(pages[0]);
+
+        ret = 0;
+        *total_out = tot_out;
+        *total_in = tot_in;
+out:
+        *out_pages = nr_pages;
+        if (out_page)
+                kunmap(out_page);
+
+        if (in_page) {
+                kunmap(in_page);
+                page_cache_release(in_page);
+        }
+
+        return ret;
+}
+
+static int lzo_decompress_biovec(struct list_head *ws,
+                                 struct page **pages_in,
+                                 u64 disk_start,
+                                 struct bio_vec *bvec,
+                                 int vcnt,
+                                 size_t srclen)
+{
+        struct workspace *workspace = list_entry(ws, struct workspace, list);
+        int ret = 0, ret2;
+        char *data_in;
+        unsigned long page_in_index = 0;
+        unsigned long page_out_index = 0;
+        unsigned long total_pages_in = (srclen + PAGE_CACHE_SIZE - 1) /
+                                        PAGE_CACHE_SIZE;
+        unsigned long buf_start;
+        unsigned long buf_offset = 0;
+        unsigned long bytes;
+        unsigned long working_bytes;
+        unsigned long pg_offset;
+
+        size_t in_len;
+        size_t out_len;
+        unsigned long in_offset;
+        unsigned long in_page_bytes_left;
+        unsigned long tot_in;
+        unsigned long tot_out;
+        unsigned long tot_len;
+        char *buf;
+
+        data_in = kmap(pages_in[0]);
+        tot_len = read_compress_length(data_in);
+
+        tot_in = LZO_LEN;
+        in_offset = LZO_LEN;
+        tot_len = min_t(size_t, srclen, tot_len);
+        in_page_bytes_left = PAGE_CACHE_SIZE - LZO_LEN;
+
+        tot_out = 0;
+        pg_offset = 0;
+
+        while (tot_in < tot_len) {
+                in_len = read_compress_length(data_in + in_offset);
+                in_page_bytes_left -= LZO_LEN;
+                in_offset += LZO_LEN;
+                tot_in += LZO_LEN;
+
+                tot_in += in_len;
+                working_bytes = in_len;
+
+                /* fast path: avoid using the working buffer */
+                if (in_page_bytes_left >= in_len) {
+                        buf = data_in + in_offset;
+                        bytes = in_len;
+                        goto cont;
+                }
+
+                /* copy bytes from the pages into the working buffer */
+                buf = workspace->cbuf;
+                buf_offset = 0;
+                while (working_bytes) {
+                        bytes = min(working_bytes, in_page_bytes_left);
+
+                        memcpy(buf + buf_offset, data_in + in_offset, bytes);
+                        buf_offset += bytes;
+cont:
+                        working_bytes -= bytes;
+                        in_page_bytes_left -= bytes;
+                        in_offset += bytes;
+
+                        /* check if we need to pick another page */
+                        if ((working_bytes == 0 && in_page_bytes_left < LZO_LEN)
+                            || in_page_bytes_left == 0) {
+                                tot_in += in_page_bytes_left;
+
+                                if (working_bytes == 0 && tot_in >= tot_len)
+                                        break;
+
+                                kunmap(pages_in[page_in_index]);
+                                page_in_index++;
+                                if (page_in_index >= total_pages_in) {
+                                        ret = -1;
+                                        data_in = NULL;
+                                        goto done;
+                                }
+                                data_in = kmap(pages_in[page_in_index]);
+
+                                in_page_bytes_left = PAGE_CACHE_SIZE;
+                                in_offset = 0;
+                        }
+                }
+
+                out_len = lzo1x_worst_compress(PAGE_CACHE_SIZE);
+                ret = lzo1x_decompress_safe(buf, in_len, workspace->buf,
+                                            &out_len);
+                if (ret != LZO_E_OK) {
+                        printk(KERN_WARNING "btrfs decompress failed\n");
+                        ret = -1;
+                        break;
+                }
+
+                buf_start = tot_out;
+                tot_out += out_len;
+
+                ret2 = btrfs_decompress_buf2page(workspace->buf, buf_start,
+                                                 tot_out, disk_start,
+                                                 bvec, vcnt,
+                                                 &page_out_index, &pg_offset);
+                if (ret2 == 0)
+                        break;
+        }
+done:
+        if (data_in)
+                kunmap(pages_in[page_in_index]);
+        return ret;
+}
+
+static int lzo_decompress(struct list_head *ws, unsigned char *data_in,
+                          struct page *dest_page,
+                          unsigned long start_byte,
+                          size_t srclen, size_t destlen)
+{
+        struct workspace *workspace = list_entry(ws, struct workspace, list);
+        size_t in_len;
+        size_t out_len;
+        size_t tot_len;
+        int ret = 0;
+        char *kaddr;
+        unsigned long bytes;
+
+        BUG_ON(srclen < LZO_LEN);
+
+        tot_len = read_compress_length(data_in);
+        data_in += LZO_LEN;
+
+        in_len = read_compress_length(data_in);
+        data_in += LZO_LEN;
+
+        out_len = PAGE_CACHE_SIZE;
+        ret = lzo1x_decompress_safe(data_in, in_len, workspace->buf, &out_len);
+        if (ret != LZO_E_OK) {
+                printk(KERN_WARNING "btrfs decompress failed!\n");
+                ret = -1;
+                goto out;
+        }
+
+        if (out_len < start_byte) {
+                ret = -1;
+                goto out;
+        }
+
+        bytes = min_t(unsigned long, destlen, out_len - start_byte);
+
+        kaddr = kmap_atomic(dest_page, KM_USER0);
+        memcpy(kaddr, workspace->buf + start_byte, bytes);
+        kunmap_atomic(kaddr, KM_USER0);
+out:
+        return ret;
+}
+
+struct btrfs_compress_op btrfs_lzo_compress = {
+        .alloc_workspace        = lzo_alloc_workspace,
+        .free_workspace         = lzo_free_workspace,
+        .compress_pages         = lzo_compress_pages,
+        .decompress_biovec      = lzo_decompress_biovec,
+        .decompress             = lzo_decompress,
+};
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index ae7737e352c9..2b61e1ddcd99 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -172,7 +172,7 @@ static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
  */
 static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
                                       u64 start, u64 len, u64 disk_len,
-                                      int type, int dio)
+                                      int type, int dio, int compress_type)
 {
         struct btrfs_ordered_inode_tree *tree;
         struct rb_node *node;
@@ -189,6 +189,7 @@ static int __btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
         entry->disk_len = disk_len;
         entry->bytes_left = len;
         entry->inode = inode;
+        entry->compress_type = compress_type;
         if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
                 set_bit(type, &entry->flags);
 
@@ -220,14 +221,25 @@ int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
                              u64 start, u64 len, u64 disk_len, int type)
 {
         return __btrfs_add_ordered_extent(inode, file_offset, start, len,
-                                          disk_len, type, 0);
+                                          disk_len, type, 0,
+                                          BTRFS_COMPRESS_NONE);
 }
 
 int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
                                  u64 start, u64 len, u64 disk_len, int type)
 {
         return __btrfs_add_ordered_extent(inode, file_offset, start, len,
-                                          disk_len, type, 1);
+                                          disk_len, type, 1,
+                                          BTRFS_COMPRESS_NONE);
+}
+
+int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
+                                      u64 start, u64 len, u64 disk_len,
+                                      int type, int compress_type)
+{
+        return __btrfs_add_ordered_extent(inode, file_offset, start, len,
+                                          disk_len, type, 0,
+                                          compress_type);
 }
 
 /*
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index 61dca83119dd..ff1f69aa1883 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -68,7 +68,7 @@ struct btrfs_ordered_sum {
 
 #define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */
 
-#define BTRFS_ORDERED_COMPRESSED 3 /* writing a compressed extent */
+#define BTRFS_ORDERED_COMPRESSED 3 /* writing a zlib compressed extent */
 
 #define BTRFS_ORDERED_PREALLOC 4 /* set when writing to prealloced extent */
 
@@ -93,6 +93,9 @@ struct btrfs_ordered_extent {
         /* flags (described above) */
         unsigned long flags;
 
+        /* compression algorithm */
+        int compress_type;
+
         /* reference count */
         atomic_t refs;
 
@@ -148,6 +151,9 @@ int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
                              u64 start, u64 len, u64 disk_len, int type);
 int btrfs_add_ordered_extent_dio(struct inode *inode, u64 file_offset,
                                  u64 start, u64 len, u64 disk_len, int type);
+int btrfs_add_ordered_extent_compress(struct inode *inode, u64 file_offset,
+                                      u64 start, u64 len, u64 disk_len,
+                                      int type, int compress_type);
 int btrfs_add_ordered_sum(struct inode *inode,
                           struct btrfs_ordered_extent *entry,
                           struct btrfs_ordered_sum *sum);
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 61bd79abb805..a1a76b2a61f9 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -69,9 +69,9 @@ enum {
         Opt_degraded, Opt_subvol, Opt_subvolid, Opt_device, Opt_nodatasum,
         Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd,
         Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress,
-        Opt_compress_force, Opt_notreelog, Opt_ratio, Opt_flushoncommit,
-        Opt_discard, Opt_space_cache, Opt_clear_cache, Opt_err,
-        Opt_user_subvol_rm_allowed,
+        Opt_compress_type, Opt_compress_force, Opt_compress_force_type,
+        Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard,
+        Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed, Opt_err,
 };
 
 static match_table_t tokens = {
@@ -86,7 +86,9 @@ static match_table_t tokens = {
         {Opt_alloc_start, "alloc_start=%s"},
         {Opt_thread_pool, "thread_pool=%d"},
         {Opt_compress, "compress"},
+        {Opt_compress_type, "compress=%s"},
         {Opt_compress_force, "compress-force"},
+        {Opt_compress_force_type, "compress-force=%s"},
         {Opt_ssd, "ssd"},
         {Opt_ssd_spread, "ssd_spread"},
         {Opt_nossd, "nossd"},
@@ -112,6 +114,8 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
         char *p, *num, *orig;
         int intarg;
         int ret = 0;
+        char *compress_type;
+        bool compress_force = false;
 
         if (!options)
                 return 0;
@@ -154,14 +158,32 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
                         btrfs_set_opt(info->mount_opt, NODATACOW);
                         btrfs_set_opt(info->mount_opt, NODATASUM);
                         break;
-                case Opt_compress:
-                        printk(KERN_INFO "btrfs: use compression\n");
-                        btrfs_set_opt(info->mount_opt, COMPRESS);
-                        break;
                 case Opt_compress_force:
-                        printk(KERN_INFO "btrfs: forcing compression\n");
-                        btrfs_set_opt(info->mount_opt, FORCE_COMPRESS);
+                case Opt_compress_force_type:
+                        compress_force = true;
+                case Opt_compress:
+                case Opt_compress_type:
+                        if (token == Opt_compress ||
+                            token == Opt_compress_force ||
+                            strcmp(args[0].from, "zlib") == 0) {
+                                compress_type = "zlib";
+                                info->compress_type = BTRFS_COMPRESS_ZLIB;
+                        } else if (strcmp(args[0].from, "lzo") == 0) {
+                                compress_type = "lzo";
+                                info->compress_type = BTRFS_COMPRESS_LZO;
+                        } else {
+                                ret = -EINVAL;
+                                goto out;
+                        }
+
                         btrfs_set_opt(info->mount_opt, COMPRESS);
+                        if (compress_force) {
+                                btrfs_set_opt(info->mount_opt, FORCE_COMPRESS);
+                                pr_info("btrfs: force %s compression\n",
+                                        compress_type);
+                        } else
+                                pr_info("btrfs: use %s compression\n",
+                                        compress_type);
                         break;
                 case Opt_ssd:
                         printk(KERN_INFO "btrfs: use ssd allocation scheme\n");
@@ -898,10 +920,14 @@ static int __init init_btrfs_fs(void)
         if (err)
                 return err;
 
-        err = btrfs_init_cachep();
+        err = btrfs_init_compress();
         if (err)
                 goto free_sysfs;
 
+        err = btrfs_init_cachep();
+        if (err)
+                goto free_compress;
+
         err = extent_io_init();
         if (err)
                 goto free_cachep;
@@ -929,6 +955,8 @@ free_extent_io:
         extent_io_exit();
 free_cachep:
         btrfs_destroy_cachep();
+free_compress:
+        btrfs_exit_compress();
 free_sysfs:
         btrfs_exit_sysfs();
         return err;
@@ -943,7 +971,7 @@ static void __exit exit_btrfs_fs(void)
         unregister_filesystem(&btrfs_fs_type);
         btrfs_exit_sysfs();
         btrfs_cleanup_fs_uuids();
-        btrfs_zlib_exit();
+        btrfs_exit_compress();
 }
 
 module_init(init_btrfs_fs)
diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c
index b9cd5445f71c..f5ec2d44150d 100644
--- a/fs/btrfs/zlib.c
+++ b/fs/btrfs/zlib.c
@@ -32,15 +32,6 @@
 #include <linux/bio.h>
 #include "compression.h"
 
-/* Plan: call deflate() with avail_in == *sourcelen,
-        avail_out = *dstlen - 12 and flush == Z_FINISH.
-        If it doesn't manage to finish, call it again with
-        avail_in == 0 and avail_out set to the remaining 12
-        bytes for it to clean up.
-   Q: Is 12 bytes sufficient?
-*/
-#define STREAM_END_SPACE 12
-
 struct workspace {
         z_stream inf_strm;
         z_stream def_strm;
@@ -48,152 +39,51 @@ struct workspace {
         struct list_head list;
 };
 
-static LIST_HEAD(idle_workspace);
-static DEFINE_SPINLOCK(workspace_lock);
-static unsigned long num_workspace;
-static atomic_t alloc_workspace = ATOMIC_INIT(0);
-static DECLARE_WAIT_QUEUE_HEAD(workspace_wait);
+static void zlib_free_workspace(struct list_head *ws)
+{
+        struct workspace *workspace = list_entry(ws, struct workspace, list);
 
-/*
- * this finds an available zlib workspace or allocates a new one
- * NULL or an ERR_PTR is returned if things go bad.
- */
-static struct workspace *find_zlib_workspace(void)
+        vfree(workspace->def_strm.workspace);
+        vfree(workspace->inf_strm.workspace);
+        kfree(workspace->buf);
+        kfree(workspace);
+}
+
+static struct list_head *zlib_alloc_workspace(void)
 {
         struct workspace *workspace;
-        int ret;
-        int cpus = num_online_cpus();
-
-again:
-        spin_lock(&workspace_lock);
-        if (!list_empty(&idle_workspace)) {
-                workspace = list_entry(idle_workspace.next, struct workspace,
-                                       list);
-                list_del(&workspace->list);
-                num_workspace--;
-                spin_unlock(&workspace_lock);
-                return workspace;
 
-        }
-        spin_unlock(&workspace_lock);
-        if (atomic_read(&alloc_workspace) > cpus) {
-                DEFINE_WAIT(wait);
-                prepare_to_wait(&workspace_wait, &wait, TASK_UNINTERRUPTIBLE);
-                if (atomic_read(&alloc_workspace) > cpus)
-                        schedule();
-                finish_wait(&workspace_wait, &wait);
-                goto again;
-        }
-        atomic_inc(&alloc_workspace);
         workspace = kzalloc(sizeof(*workspace), GFP_NOFS);
-        if (!workspace) {
-                ret = -ENOMEM;
-                goto fail;
-        }
+        if (!workspace)
+                return ERR_PTR(-ENOMEM);
 
         workspace->def_strm.workspace = vmalloc(zlib_deflate_workspacesize());
-        if (!workspace->def_strm.workspace) {
-                ret = -ENOMEM;
-                goto fail;
-        }
         workspace->inf_strm.workspace = vmalloc(zlib_inflate_workspacesize());
-        if (!workspace->inf_strm.workspace) {
-                ret = -ENOMEM;
-                goto fail_inflate;
-        }
         workspace->buf = kmalloc(PAGE_CACHE_SIZE, GFP_NOFS);
-        if (!workspace->buf) {
-                ret = -ENOMEM;
-                goto fail_kmalloc;
-        }
-        return workspace;
-
-fail_kmalloc:
-        vfree(workspace->inf_strm.workspace);
-fail_inflate:
-        vfree(workspace->def_strm.workspace);
-fail:
-        kfree(workspace);
-        atomic_dec(&alloc_workspace);
-        wake_up(&workspace_wait);
-        return ERR_PTR(ret);
-}
-
-/*
- * put a workspace struct back on the list or free it if we have enough
- * idle ones sitting around
- */
-static int free_workspace(struct workspace *workspace)
-{
-        spin_lock(&workspace_lock);
-        if (num_workspace < num_online_cpus()) {
-                list_add_tail(&workspace->list, &idle_workspace);
-                num_workspace++;
-                spin_unlock(&workspace_lock);
-                if (waitqueue_active(&workspace_wait))
-                        wake_up(&workspace_wait);
-                return 0;
-        }
-        spin_unlock(&workspace_lock);
-        vfree(workspace->def_strm.workspace);
-        vfree(workspace->inf_strm.workspace);
-        kfree(workspace->buf);
-        kfree(workspace);
+        if (!workspace->def_strm.workspace ||
+            !workspace->inf_strm.workspace || !workspace->buf)
+                goto fail;
 
-        atomic_dec(&alloc_workspace);
-        if (waitqueue_active(&workspace_wait))
-                wake_up(&workspace_wait);
-        return 0;
-}
+        INIT_LIST_HEAD(&workspace->list);
 
-/*
- * cleanup function for module exit
- */
-static void free_workspaces(void)
-{
-        struct workspace *workspace;
-        while (!list_empty(&idle_workspace)) {
-                workspace = list_entry(idle_workspace.next, struct workspace,
-                                       list);
-                list_del(&workspace->list);
-                vfree(workspace->def_strm.workspace);
-                vfree(workspace->inf_strm.workspace);
-                kfree(workspace->buf);
-                kfree(workspace);
-                atomic_dec(&alloc_workspace);
-        }
+        return &workspace->list;
+fail:
+        zlib_free_workspace(&workspace->list);
+        return ERR_PTR(-ENOMEM);
 }
 
-/*
- * given an address space and start/len, compress the bytes.
- *
- * pages are allocated to hold the compressed result and stored
- * in 'pages'
- *
- * out_pages is used to return the number of pages allocated.  There
- * may be pages allocated even if we return an error
- *
- * total_in is used to return the number of bytes actually read.  It
- * may be smaller then len if we had to exit early because we
- * ran out of room in the pages array or because we cross the
- * max_out threshold.
- *
- * total_out is used to return the total number of compressed bytes
- *
- * max_out tells us the max number of bytes that we're allowed to
- * stuff into pages
- */
-int btrfs_zlib_compress_pages(struct address_space *mapping,
-                              u64 start, unsigned long len,
-                              struct page **pages,
-                              unsigned long nr_dest_pages,
-                              unsigned long *out_pages,
-                              unsigned long *total_in,
-                              unsigned long *total_out,
-                              unsigned long max_out)
+static int zlib_compress_pages(struct list_head *ws,
+                               struct address_space *mapping,
+                               u64 start, unsigned long len,
+                               struct page **pages,
+                               unsigned long nr_dest_pages,
+                               unsigned long *out_pages,
+                               unsigned long *total_in,
+                               unsigned long *total_out,
+                               unsigned long max_out)
 {
+        struct workspace *workspace = list_entry(ws, struct workspace, list);
         int ret;
-        struct workspace *workspace;
         char *data_in;
         char *cpage_out;
         int nr_pages = 0;
@@ -205,10 +95,6 @@ int btrfs_zlib_compress_pages(struct address_space *mapping,
         *total_out = 0;
         *total_in = 0;
 
-        workspace = find_zlib_workspace();
-        if (IS_ERR(workspace))
-                return -1;
-
         if (Z_OK != zlib_deflateInit(&workspace->def_strm, 3)) {
                 printk(KERN_WARNING "deflateInit failed\n");
                 ret = -1;
@@ -222,6 +108,10 @@ int btrfs_zlib_compress_pages(struct address_space *mapping,
         data_in = kmap(in_page);
 
         out_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
+        if (out_page == NULL) {
+                ret = -1;
+                goto out;
+        }
         cpage_out = kmap(out_page);
         pages[0] = out_page;
         nr_pages = 1;
@@ -260,6 +150,10 @@ int btrfs_zlib_compress_pages(struct address_space *mapping,
                                 goto out;
                         }
                         out_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
+                        if (out_page == NULL) {
+                                ret = -1;
+                                goto out;
+                        }
                         cpage_out = kmap(out_page);
                         pages[nr_pages] = out_page;
                         nr_pages++;
@@ -314,55 +208,26 @@ out:
                 kunmap(in_page);
                 page_cache_release(in_page);
         }
-        free_workspace(workspace);
         return ret;
 }
 
-/*
- * pages_in is an array of pages with compressed data.
- *
- * disk_start is the starting logical offset of this array in the file
- *
- * bvec is a bio_vec of pages from the file that we want to decompress into
- *
- * vcnt is the count of pages in the biovec
- *
- * srclen is the number of bytes in pages_in
- *
- * The basic idea is that we have a bio that was created by readpages.
- * The pages in the bio are for the uncompressed data, and they may not
- * be contiguous.  They all correspond to the range of bytes covered by
- * the compressed extent.
- */
-int btrfs_zlib_decompress_biovec(struct page **pages_in,
-                              u64 disk_start,
-                              struct bio_vec *bvec,
-                              int vcnt,
-                              size_t srclen)
+static int zlib_decompress_biovec(struct list_head *ws, struct page **pages_in,
+                                  u64 disk_start,
+                                  struct bio_vec *bvec,
+                                  int vcnt,
+                                  size_t srclen)
 {
-        int ret = 0;
+        struct workspace *workspace = list_entry(ws, struct workspace, list);
+        int ret = 0, ret2;
         int wbits = MAX_WBITS;
-        struct workspace *workspace;
         char *data_in;
         size_t total_out = 0;
-        unsigned long page_bytes_left;
         unsigned long page_in_index = 0;
         unsigned long page_out_index = 0;
-        struct page *page_out;
         unsigned long total_pages_in = (srclen + PAGE_CACHE_SIZE - 1) /
                                         PAGE_CACHE_SIZE;
         unsigned long buf_start;
-        unsigned long buf_offset;
-        unsigned long bytes;
-        unsigned long working_bytes;
         unsigned long pg_offset;
-        unsigned long start_byte;
-        unsigned long current_buf_start;
-        char *kaddr;
-
-        workspace = find_zlib_workspace();
-        if (IS_ERR(workspace))
-                return -ENOMEM;
 
         data_in = kmap(pages_in[page_in_index]);
         workspace->inf_strm.next_in = data_in;
@@ -372,8 +237,6 @@ int btrfs_zlib_decompress_biovec(struct page **pages_in,
         workspace->inf_strm.total_out = 0;
         workspace->inf_strm.next_out = workspace->buf;
         workspace->inf_strm.avail_out = PAGE_CACHE_SIZE;
-        page_out = bvec[page_out_index].bv_page;
-        page_bytes_left = PAGE_CACHE_SIZE;
         pg_offset = 0;
 
         /* If it's deflate, and it's got no preset dictionary, then
@@ -389,107 +252,29 @@ int btrfs_zlib_decompress_biovec(struct page **pages_in,
 
         if (Z_OK != zlib_inflateInit2(&workspace->inf_strm, wbits)) {
                 printk(KERN_WARNING "inflateInit failed\n");
-                ret = -1;
-                goto out;
+                return -1;
         }
         while (workspace->inf_strm.total_in < srclen) {
                 ret = zlib_inflate(&workspace->inf_strm, Z_NO_FLUSH);
                 if (ret != Z_OK && ret != Z_STREAM_END)
                         break;
-                /*
-                 * buf start is the byte offset we're of the start of
-                 * our workspace buffer
-                 */
-                buf_start = total_out;
 
-                /* total_out is the last byte of the workspace buffer */
+                buf_start = total_out;
                 total_out = workspace->inf_strm.total_out;
 
-                working_bytes = total_out - buf_start;
-
-                /*
-                 * start byte is the first byte of the page we're currently
-                 * copying into relative to the start of the compressed data.
-                 */
-                start_byte = page_offset(page_out) - disk_start;
-
-                if (working_bytes == 0) {
-                        /* we didn't make progress in this inflate
-                         * call, we're done
-                         */
-                        if (ret != Z_STREAM_END)
-                                ret = -1;
+                /* we didn't make progress in this inflate call, we're done */
+                if (buf_start == total_out)
                         break;
-                }
 
-                /* we haven't yet hit data corresponding to this page */
-                if (total_out <= start_byte)
-                        goto next;
-
-                /*
-                 * the start of the data we care about is offset into
-                 * the middle of our working buffer
-                 */
-                if (total_out > start_byte && buf_start < start_byte) {
-                        buf_offset = start_byte - buf_start;
-                        working_bytes -= buf_offset;
-                } else {
-                        buf_offset = 0;
-                }
-                current_buf_start = buf_start;
-
-                /* copy bytes from the working buffer into the pages */
-                while (working_bytes > 0) {
-                        bytes = min(PAGE_CACHE_SIZE - pg_offset,
-                                    PAGE_CACHE_SIZE - buf_offset);
-                        bytes = min(bytes, working_bytes);
-                        kaddr = kmap_atomic(page_out, KM_USER0);
-                        memcpy(kaddr + pg_offset, workspace->buf + buf_offset,
-                               bytes);
-                        kunmap_atomic(kaddr, KM_USER0);
-                        flush_dcache_page(page_out);
-
-                        pg_offset += bytes;
-                        page_bytes_left -= bytes;
-                        buf_offset += bytes;
-                        working_bytes -= bytes;
-                        current_buf_start += bytes;
-
-                        /* check if we need to pick another page */
-                        if (page_bytes_left == 0) {
-                                page_out_index++;
-                                if (page_out_index >= vcnt) {
-                                        ret = 0;
-                                        goto done;
-                                }
-
-                                page_out = bvec[page_out_index].bv_page;
-                                pg_offset = 0;
-                                page_bytes_left = PAGE_CACHE_SIZE;
-                                start_byte = page_offset(page_out) - disk_start;
-
-                                /*
-                                 * make sure our new page is covered by this
-                                 * working buffer
-                                 */
-                                if (total_out <= start_byte)
-                                        goto next;
-
-                                /* the next page in the biovec might not
-                                 * be adjacent to the last page, but it
-                                 * might still be found inside this working
-                                 * buffer.  bump our offset pointer
-                                 */
-                                if (total_out > start_byte &&
-                                    current_buf_start < start_byte) {
-                                        buf_offset = start_byte - buf_start;
-                                        working_bytes = total_out - start_byte;
-                                        current_buf_start = buf_start +
-                                                buf_offset;
-                                }
-                        }
+                ret2 = btrfs_decompress_buf2page(workspace->buf, buf_start,
+                                                 total_out, disk_start,
+                                                 bvec, vcnt,
+                                                 &page_out_index, &pg_offset);
+                if (ret2 == 0) {
+                        ret = 0;
+                        goto done;
                 }
-next:
+
                 workspace->inf_strm.next_out = workspace->buf;
                 workspace->inf_strm.avail_out = PAGE_CACHE_SIZE;
 
@@ -516,35 +301,21 @@ done:
         zlib_inflateEnd(&workspace->inf_strm);
         if (data_in)
                 kunmap(pages_in[page_in_index]);
-out:
-        free_workspace(workspace);
         return ret;
 }
 
-/*
- * a less complex decompression routine.  Our compressed data fits in a
- * single page, and we want to read a single page out of it.
- * start_byte tells us the offset into the compressed data we're interested in
- */
-int btrfs_zlib_decompress(unsigned char *data_in,
-                          struct page *dest_page,
-                          unsigned long start_byte,
-                          size_t srclen, size_t destlen)
+static int zlib_decompress(struct list_head *ws, unsigned char *data_in,
+                           struct page *dest_page,
+                           unsigned long start_byte,
+                           size_t srclen, size_t destlen)
 {
+        struct workspace *workspace = list_entry(ws, struct workspace, list);
         int ret = 0;
         int wbits = MAX_WBITS;
-        struct workspace *workspace;
         unsigned long bytes_left = destlen;
         unsigned long total_out = 0;
         char *kaddr;
 
-        if (destlen > PAGE_CACHE_SIZE)
-                return -ENOMEM;
-
-        workspace = find_zlib_workspace();
-        if (IS_ERR(workspace))
-                return -ENOMEM;
-
         workspace->inf_strm.next_in = data_in;
         workspace->inf_strm.avail_in = srclen;
         workspace->inf_strm.total_in = 0;
@@ -565,8 +336,7 @@ int btrfs_zlib_decompress(unsigned char *data_in,
 
         if (Z_OK != zlib_inflateInit2(&workspace->inf_strm, wbits)) {
                 printk(KERN_WARNING "inflateInit failed\n");
-                ret = -1;
-                goto out;
+                return -1;
         }
 
         while (bytes_left > 0) {
@@ -616,12 +386,13 @@ next:
                 ret = 0;
 
         zlib_inflateEnd(&workspace->inf_strm);
-out:
-        free_workspace(workspace);
         return ret;
 }
 
-void btrfs_zlib_exit(void)
-{
-    free_workspaces();
-}
+struct btrfs_compress_op btrfs_zlib_compress = {
+        .alloc_workspace        = zlib_alloc_workspace,
+        .free_workspace         = zlib_free_workspace,
+        .compress_pages         = zlib_compress_pages,
+        .decompress_biovec      = zlib_decompress_biovec,
+        .decompress             = zlib_decompress,
+};