GFS2: Use range based functions for rgrp sync/invalidation

Each rgrp header is represented as a single extent on disk, so we
can calculate the position within the address space, since we are
using address spaces mapped 1:1 to the disk. This means that it
is possible to use the range based versions of filemap_fdatawrite/wait
and for invalidating the page cache.

Our eventual intent is to then be able to merge the address spaces
used for rgrps into a single address space, rather than to have
one for each glock, saving memory and reducing complexity.

Since during umount, the rgrp structures are disposed of before
the glocks, we need to store the extent information in the glock
so that is is available for a final invalidation. This patch uses
a field which is otherwise unused in rgrp glocks to do that, so
that we do not have to expand the size of a glock.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index f88dcd92501098e4a9bca28724da34e8df5a0154..1b192c8d404dc228faee9184059502264a915163 100644 (file)
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -142,8 +142,8 @@ static void rgrp_go_sync(struct gfs2_glock *gl)
        GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);
 
        gfs2_log_flush(gl->gl_sbd, gl);
-       filemap_fdatawrite(metamapping);
-       error = filemap_fdatawait(metamapping);
+       filemap_fdatawrite_range(metamapping, gl->gl_vm.start, gl->gl_vm.end);
+       error = filemap_fdatawait_range(metamapping, gl->gl_vm.start, gl->gl_vm.end);
         mapping_set_error(metamapping, error);
        gfs2_ail_empty_gl(gl);
 
@@ -170,7 +170,7 @@ static void rgrp_go_inval(struct gfs2_glock *gl, int flags)
 
        WARN_ON_ONCE(!(flags & DIO_METADATA));
        gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
-       truncate_inode_pages(mapping, 0);
+       truncate_inode_pages_range(mapping, gl->gl_vm.start, gl->gl_vm.end);
 
        if (gl->gl_object) {
                struct gfs2_rgrpd *rgd = (struct gfs2_rgrpd *)gl->gl_object;

diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 01328162c9527503536e4e95c4a6fdcb3d4caa58..e6544ee0c1379816bf40e8eda1da6eee86093a8d 100644 (file)
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -351,7 +351,15 @@ struct gfs2_glock {
        atomic_t gl_ail_count;
        atomic_t gl_revokes;
        struct delayed_work gl_work;
-       struct work_struct gl_delete;
+       union {
+               /* For inode and iopen glocks only */
+               struct work_struct gl_delete;
+               /* For rgrp glocks only */
+               struct {
+                       loff_t start;
+                       loff_t end;
+               } gl_vm;
+       };
        struct rcu_head gl_rcu;
 };
 

diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index 2584710f64596117c57f004b01e84cbf51fb7191..183cf0f0052d9c7fa78d8b369c7b4a7d8b0c452c 100644 (file)
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -886,6 +886,7 @@ static int rgd_insert(struct gfs2_rgrpd *rgd)
 static int read_rindex_entry(struct gfs2_inode *ip)
 {
        struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
+       const unsigned bsize = sdp->sd_sb.sb_bsize;
        loff_t pos = sdp->sd_rgrps * sizeof(struct gfs2_rindex);
        struct gfs2_rindex buf;
        int error;
@@ -923,6 +924,8 @@ static int read_rindex_entry(struct gfs2_inode *ip)
                goto fail;
 
        rgd->rd_gl->gl_object = rgd;
+       rgd->rd_gl->gl_vm.start = rgd->rd_addr * bsize;
+       rgd->rd_gl->gl_vm.end = rgd->rd_gl->gl_vm.start + (rgd->rd_length * bsize) - 1;
        rgd->rd_rgl = (struct gfs2_rgrp_lvb *)rgd->rd_gl->gl_lksb.sb_lvbptr;
        rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
        if (rgd->rd_data > sdp->sd_max_rg_data)