diff options
author | Steven Whitehouse <swhiteho@redhat.com> | 2007-10-15 15:40:33 +0100 |
---|---|---|
committer | Steven Whitehouse <swhiteho@redhat.com> | 2008-01-25 08:07:13 +0000 |
commit | 3cc3f710ce0effe397b830826a1a081fa81f11c7 (patch) | |
tree | 53f69f1b8d1cbc2849c6bac08ce7786f3ecd7447 /fs/gfs2/ops_address.c | |
parent | 51ff87bdd9f21a5d3672517b75d25ab5842d94a8 (diff) |
[GFS2] Use ->page_mkwrite() for mmap()
This cleans up the mmap() code path for GFS2 by implementing the
page_mkwrite function for GFS2. We are thus able to use the
generic filemap_fault function for our ->fault() implementation.
This now means that shared writable mappings will be much more
efficiently shared across the cluster if there is a reasonable
proportion of read activity (the greater proportion, the better).
As a side effect, it also reduces the size of the code, removes
special cases from readpage and readpages, and makes the code
path easier to follow.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Diffstat (limited to 'fs/gfs2/ops_address.c')
-rw-r--r-- | fs/gfs2/ops_address.c | 45 |
1 files changed, 8 insertions, 37 deletions
diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c index 9bb24b1d9c0..1696e5d9d11 100644 --- a/fs/gfs2/ops_address.c +++ b/fs/gfs2/ops_address.c @@ -265,9 +265,7 @@ static int __gfs2_readpage(void *file, struct page *page) * @file: The file to read * @page: The page of the file * - * This deals with the locking required. If the GFF_EXLOCK flags is set - * then we already hold the glock (due to page fault) and thus we call - * __gfs2_readpage() directly. Otherwise we use a trylock in order to + * This deals with the locking required. We use a trylock in order to * avoid the page lock / glock ordering problems returning AOP_TRUNCATED_PAGE * in the event that we are unable to get the lock. */ @@ -278,12 +276,6 @@ static int gfs2_readpage(struct file *file, struct page *page) struct gfs2_holder gh; int error; - if (file) { - struct gfs2_file *gf = file->private_data; - if (test_bit(GFF_EXLOCK, &gf->f_flags)) - return __gfs2_readpage(file, page); - } - gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME|LM_FLAG_TRY_1CB, &gh); error = gfs2_glock_nq_atime(&gh); if (unlikely(error)) { @@ -354,9 +346,8 @@ int gfs2_internal_read(struct gfs2_inode *ip, struct file_ra_state *ra_state, * 2. We don't handle stuffed files here we let readpage do the honours. * 3. mpage_readpages() does most of the heavy lifting in the common case. * 4. gfs2_get_block() is relied upon to set BH_Boundary in the right places. - * 5. We use LM_FLAG_TRY_1CB here, effectively we then have lock-ahead as - * well as read-ahead. */ + static int gfs2_readpages(struct file *file, struct address_space *mapping, struct list_head *pages, unsigned nr_pages) { @@ -364,40 +355,20 @@ static int gfs2_readpages(struct file *file, struct address_space *mapping, struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_sbd *sdp = GFS2_SB(inode); struct gfs2_holder gh; - int ret = 0; - int do_unlock = 0; + int ret; - if (file) { - struct gfs2_file *gf = file->private_data; - if (test_bit(GFF_EXLOCK, &gf->f_flags)) - goto skip_lock; - } - gfs2_holder_init(ip->i_gl, LM_ST_SHARED, - LM_FLAG_TRY_1CB|GL_ATIME, &gh); - do_unlock = 1; + gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh); ret = gfs2_glock_nq_atime(&gh); - if (ret == GLR_TRYFAILED) - goto out_noerror; if (unlikely(ret)) - goto out_unlock; -skip_lock: + goto out_uninit; if (!gfs2_is_stuffed(ip)) ret = mpage_readpages(mapping, pages, nr_pages, gfs2_get_block); - - if (do_unlock) { - gfs2_glock_dq_m(1, &gh); - gfs2_holder_uninit(&gh); - } -out: + gfs2_glock_dq(&gh); +out_uninit: + gfs2_holder_uninit(&gh); if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) ret = -EIO; return ret; -out_noerror: - ret = 0; -out_unlock: - if (do_unlock) - gfs2_holder_uninit(&gh); - goto out; } /** |