ceph: use fscache as a local presisent cache
Adding support for fscache to the Ceph filesystem. This would bring it to on
par with some of the other network filesystems in Linux (like NFS, AFS, etc...)
In order to mount the filesystem with fscache the 'fsc' mount option must be
passed.
Signed-off-by: Milosz Tanski <milosz@adfin.com>
Signed-off-by: Sage Weil <sage@inktank.com>
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 3bed7da..3a21a7c 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -11,6 +11,7 @@
#include "super.h"
#include "mds_client.h"
+#include "cache.h"
#include <linux/ceph/osd_client.h>
/*
@@ -144,6 +145,11 @@
return;
}
+ ceph_invalidate_fscache_page(inode, page);
+
+ if (!PagePrivate(page))
+ return;
+
/*
* We can get non-dirty pages here due to races between
* set_page_dirty and truncate_complete_page; just spit out a
@@ -163,14 +169,17 @@
ClearPagePrivate(page);
}
-/* just a sanity check */
static int ceph_releasepage(struct page *page, gfp_t g)
{
struct inode *inode = page->mapping ? page->mapping->host : NULL;
dout("%p releasepage %p idx %lu\n", inode, page, page->index);
WARN_ON(PageDirty(page));
- WARN_ON(PagePrivate(page));
- return 0;
+
+ /* Can we release the page from the cache? */
+ if (!ceph_release_fscache_page(page, g))
+ return 0;
+
+ return !PagePrivate(page);
}
/*
@@ -180,11 +189,16 @@
{
struct inode *inode = file_inode(filp);
struct ceph_inode_info *ci = ceph_inode(inode);
- struct ceph_osd_client *osdc =
+ struct ceph_osd_client *osdc =
&ceph_inode_to_client(inode)->client->osdc;
int err = 0;
u64 len = PAGE_CACHE_SIZE;
+ err = ceph_readpage_from_fscache(inode, page);
+
+ if (err == 0)
+ goto out;
+
dout("readpage inode %p file %p page %p index %lu\n",
inode, filp, page, page->index);
err = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout,
@@ -202,6 +216,9 @@
}
SetPageUptodate(page);
+ if (err == 0)
+ ceph_readpage_to_fscache(inode, page);
+
out:
return err < 0 ? err : 0;
}
@@ -244,6 +261,7 @@
page->index);
flush_dcache_page(page);
SetPageUptodate(page);
+ ceph_readpage_to_fscache(inode, page);
unlock_page(page);
page_cache_release(page);
bytes -= PAGE_CACHE_SIZE;
@@ -313,7 +331,7 @@
page = list_entry(page_list->prev, struct page, lru);
BUG_ON(PageLocked(page));
list_del(&page->lru);
-
+
dout("start_read %p adding %p idx %lu\n", inode, page,
page->index);
if (add_to_page_cache_lru(page, &inode->i_data, page->index,
@@ -360,6 +378,12 @@
int rc = 0;
int max = 0;
+ rc = ceph_readpages_from_fscache(mapping->host, mapping, page_list,
+ &nr_pages);
+
+ if (rc == 0)
+ goto out;
+
if (fsc->mount_options->rsize >= PAGE_CACHE_SIZE)
max = (fsc->mount_options->rsize + PAGE_CACHE_SIZE - 1)
>> PAGE_SHIFT;
@@ -479,6 +503,8 @@
CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))
set_bdi_congested(&fsc->backing_dev_info, BLK_RW_ASYNC);
+ ceph_readpage_to_fscache(inode, page);
+
set_page_writeback(page);
err = ceph_osdc_writepages(osdc, ceph_vino(inode),
&ci->i_layout, snapc,
@@ -534,7 +560,6 @@
pagevec_release(&pvec);
}
-
/*
* async writeback completion handler.
*
