gfs2: Extended attribute readahead

When gfs2 allocates an inode and its extended attribute block next to
each other at inode create time, the inode's directory entry indicates
that in de_rahead.  In that case, we can readahead the extended
attribute block when we read in the inode.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>

8 files changed, 46 insertions, 14 deletions

diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c
index ad8a5b757cc7..c2486598fb87 100644
--- a/fs/gfs2/dir.c
+++ b/fs/gfs2/dir.c
@@ -108,7 +108,7 @@ static int gfs2_dir_get_existing_buffer(struct gfs2_inode *ip, u64 block,
         struct buffer_head *bh;
         int error;
 
-        error = gfs2_meta_read(ip->i_gl, block, DIO_WAIT, &bh);
+        error = gfs2_meta_read(ip->i_gl, block, DIO_WAIT, 0, &bh);
         if (error)
                 return error;
         if (gfs2_metatype_check(GFS2_SB(&ip->i_inode), bh, GFS2_METATYPE_JD)) {
@@ -305,7 +305,7 @@ static int gfs2_dir_read_data(struct gfs2_inode *ip, __be64 *buf,
                         BUG_ON(extlen < 1);
                         bh = gfs2_meta_ra(ip->i_gl, dblock, extlen);
                 } else {
-                        error = gfs2_meta_read(ip->i_gl, dblock, DIO_WAIT, &bh);
+                        error = gfs2_meta_read(ip->i_gl, dblock, DIO_WAIT, 0, &bh);
                         if (error)
                                 goto fail;
                 }
@@ -723,7 +723,7 @@ static int get_leaf(struct gfs2_inode *dip, u64 leaf_no,
 {
         int error;
 
-        error = gfs2_meta_read(dip->i_gl, leaf_no, DIO_WAIT, bhp);
+        error = gfs2_meta_read(dip->i_gl, leaf_no, DIO_WAIT, 0, bhp);
         if (!error && gfs2_metatype_check(GFS2_SB(&dip->i_inode), *bhp, GFS2_METATYPE_LF)) {
                 /* pr_info("block num=%llu\n", leaf_no); */
                 error = -EIO;
@@ -1560,15 +1560,22 @@ struct inode *gfs2_dir_search(struct inode *dir, const struct qstr *name,
 
         dent = gfs2_dirent_search(dir, name, gfs2_dirent_find, &bh);
         if (dent) {
+                struct inode *inode;
+                u16 rahead;
+
                 if (IS_ERR(dent))
                         return ERR_CAST(dent);
                 dtype = be16_to_cpu(dent->de_type);
+                rahead = be16_to_cpu(dent->de_rahead);
                 addr = be64_to_cpu(dent->de_inum.no_addr);
                 formal_ino = be64_to_cpu(dent->de_inum.no_formal_ino);
                 brelse(bh);
                 if (fail_on_exist)
                         return ERR_PTR(-EEXIST);
-                return gfs2_inode_lookup(dir->i_sb, dtype, addr, formal_ino, 0);
+                inode = gfs2_inode_lookup(dir->i_sb, dtype, addr, formal_ino, 0);
+                if (!IS_ERR(inode))
+                        GFS2_I(inode)->i_rahead = rahead;
+                return inode;
         }
         return ERR_PTR(-ENOENT);
 }
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index de7b4f97ac75..77e778496903 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -402,6 +402,7 @@ struct gfs2_inode {
         u32 i_diskflags;
         u8 i_height;
         u8 i_depth;
+        u16 i_rahead;
 };
 
 /*
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index 0e1d4be5865a..0f24828f8488 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -187,6 +187,21 @@ struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno)
         return bh;
 }
 
+static void gfs2_meta_readahead(struct gfs2_glock *gl, u64 blkno)
+{
+        struct buffer_head *bh;
+
+        bh = gfs2_getbuf(gl, blkno, 1);
+        lock_buffer(bh);
+        if (buffer_uptodate(bh)) {
+                unlock_buffer(bh);
+                brelse(bh);
+                return;
+        }
+        bh->b_end_io = end_buffer_read_sync;
+        submit_bh(READA | REQ_META | REQ_PRIO, bh);
+}
+
 /**
  * gfs2_meta_read - Read a block from disk
  * @gl: The glock covering the block
@@ -198,7 +213,7 @@ struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno)
  */
 
 int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
-                   struct buffer_head **bhp)
+                   int rahead, struct buffer_head **bhp)
 {
         struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
         struct buffer_head *bh;
@@ -213,11 +228,15 @@ int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
         lock_buffer(bh);
         if (buffer_uptodate(bh)) {
                 unlock_buffer(bh);
+                if (rahead)
+                        gfs2_meta_readahead(gl, blkno + 1);
                 return 0;
         }
         bh->b_end_io = end_buffer_read_sync;
         get_bh(bh);
         submit_bh(READ_SYNC | REQ_META | REQ_PRIO, bh);
+        if (rahead)
+                gfs2_meta_readahead(gl, blkno + 1);
         if (!(flags & DIO_WAIT))
                 return 0;
 
@@ -341,8 +360,12 @@ int gfs2_meta_indirect_buffer(struct gfs2_inode *ip, int height, u64 num,
         struct buffer_head *bh;
         int ret = 0;
         u32 mtype = height ? GFS2_METATYPE_IN : GFS2_METATYPE_DI;
+        int rahead = 0;
+
+        if (num == ip->i_no_addr)
+                rahead = ip->i_rahead;
 
-        ret = gfs2_meta_read(gl, num, DIO_WAIT, &bh);
+        ret = gfs2_meta_read(gl, num, DIO_WAIT, rahead, &bh);
         if (ret == 0 && gfs2_metatype_check(sdp, bh, mtype)) {
                 brelse(bh);
                 ret = -EIO;
diff --git a/fs/gfs2/meta_io.h b/fs/gfs2/meta_io.h
index 8ca161567a93..c5086c8af5ed 100644
--- a/fs/gfs2/meta_io.h
+++ b/fs/gfs2/meta_io.h
@@ -53,7 +53,7 @@ static inline struct gfs2_sbd *gfs2_mapping2sbd(struct address_space *mapping)
 
 extern struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno);
 extern int gfs2_meta_read(struct gfs2_glock *gl, u64 blkno, int flags,
-                          struct buffer_head **bhp);
+                          int rahead, struct buffer_head **bhp);
 extern int gfs2_meta_wait(struct gfs2_sbd *sdp, struct buffer_head *bh);
 extern struct buffer_head *gfs2_getbuf(struct gfs2_glock *gl, u64 blkno,
                                        int create);
diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index 3a31226531ea..e01298d922c0 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -388,7 +388,7 @@ static int bh_get(struct gfs2_quota_data *qd)
         error = gfs2_block_map(&ip->i_inode, block, &bh_map, 0);
         if (error)
                 goto fail;
-        error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, &bh);
+        error = gfs2_meta_read(ip->i_gl, bh_map.b_blocknr, DIO_WAIT, 0, &bh);
         if (error)
                 goto fail;
         error = -EIO;
diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index c134c0462cee..ac0a65d94a7e 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -1158,7 +1158,7 @@ static int gfs2_rgrp_bh_get(struct gfs2_rgrpd *rgd)
 
         for (x = 0; x < length; x++) {
                 bi = rgd->rd_bits + x;
-                error = gfs2_meta_read(gl, rgd->rd_addr + x, 0, &bi->bi_bh);
+                error = gfs2_meta_read(gl, rgd->rd_addr + x, 0, 0, &bi->bi_bh);
                 if (error)
                         goto fail;
         }
diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
index 894fb01a91da..8f94282db2fe 100644
--- a/fs/gfs2/super.c
+++ b/fs/gfs2/super.c
@@ -1633,6 +1633,7 @@ static struct inode *gfs2_alloc_inode(struct super_block *sb)
                 ip->i_gl = NULL;
                 ip->i_rgd = NULL;
                 ip->i_res = NULL;
+                ip->i_rahead = 0;
         }
         return &ip->i_inode;
 }
diff --git a/fs/gfs2/xattr.c b/fs/gfs2/xattr.c
index 4c096fa9e2a1..f0fe88449bd2 100644
--- a/fs/gfs2/xattr.c
+++ b/fs/gfs2/xattr.c
@@ -119,7 +119,7 @@ static int ea_foreach(struct gfs2_inode *ip, ea_call_t ea_call, void *data)
         __be64 *eablk, *end;
         int error;
 
-        error = gfs2_meta_read(ip->i_gl, ip->i_eattr, DIO_WAIT, &bh);
+        error = gfs2_meta_read(ip->i_gl, ip->i_eattr, DIO_WAIT, 0, &bh);
         if (error)
                 return error;
 
@@ -143,7 +143,7 @@ static int ea_foreach(struct gfs2_inode *ip, ea_call_t ea_call, void *data)
                         break;
                 bn = be64_to_cpu(*eablk);
 
-                error = gfs2_meta_read(ip->i_gl, bn, DIO_WAIT, &eabh);
+                error = gfs2_meta_read(ip->i_gl, bn, DIO_WAIT, 0, &eabh);
                 if (error)
                         break;
                 error = ea_foreach_i(ip, eabh, ea_call, data);
@@ -477,7 +477,7 @@ static int gfs2_iter_unstuffed(struct gfs2_inode *ip, struct gfs2_ea_header *ea,
                 return -ENOMEM;
 
         for (x = 0; x < nptrs; x++) {
-                error = gfs2_meta_read(ip->i_gl, be64_to_cpu(*dataptrs), 0,
+                error = gfs2_meta_read(ip->i_gl, be64_to_cpu(*dataptrs), 0, 0,
                                        bh + x);
                 if (error) {
                         while (x--)
@@ -977,7 +977,7 @@ static int ea_set_block(struct gfs2_inode *ip, struct gfs2_ea_request *er,
         if (ip->i_diskflags & GFS2_DIF_EA_INDIRECT) {
                 __be64 *end;
 
-                error = gfs2_meta_read(ip->i_gl, ip->i_eattr, DIO_WAIT,
+                error = gfs2_meta_read(ip->i_gl, ip->i_eattr, DIO_WAIT, 0,
                                        &indbh);
                 if (error)
                         return error;
@@ -1303,7 +1303,7 @@ static int ea_dealloc_indirect(struct gfs2_inode *ip)
 
         memset(&rlist, 0, sizeof(struct gfs2_rgrp_list));
 
-        error = gfs2_meta_read(ip->i_gl, ip->i_eattr, DIO_WAIT, &indbh);
+        error = gfs2_meta_read(ip->i_gl, ip->i_eattr, DIO_WAIT, 0, &indbh);
         if (error)
                 return error;