Currently, fscache only plays as read cache for ceph, this patch
enables it plays as the write through cache as well.
A small trick to be discussed: if the writing to OSD finishes before
the writing to fscache, the fscache writing is cancelled to avoid
slow down the writepages() process.
Signed-off-by: Min Chen <minchen@xxxxxxxxxxxxxxx>
Signed-off-by: Li Wang <liwang@xxxxxxxxxxxxxxx>
Signed-off-by: Yunchuan Wen <yunchuanwen@xxxxxxxxxxxxxxx>
---
fs/ceph/addr.c | 10 +++++++---
fs/ceph/cache.c | 29 +++++++++++++++++++++++++++++
fs/ceph/cache.h | 13 +++++++++++++
3 files changed, 49 insertions(+), 3 deletions(-)
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 6df8bd4..2465c49 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -506,7 +506,7 @@ static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))
set_bdi_congested(&fsc->backing_dev_info, BLK_RW_ASYNC);
- ceph_readpage_to_fscache(inode, page);
+ ceph_writepage_to_fscache(inode, page);
set_page_writeback(page);
err = ceph_osdc_writepages(osdc, ceph_vino(inode),
@@ -634,6 +634,7 @@ static void writepages_finish(struct ceph_osd_request *req,
if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0)
generic_error_remove_page(inode->i_mapping, page);
+ ceph_maybe_release_fscache_page(inode, page);
unlock_page(page);
}
dout("%p wrote+cleaned %d pages\n", inode, wrote);
@@ -746,7 +747,7 @@ retry:
while (!done && index <= end) {
int num_ops = do_sync ? 2 : 1;
- unsigned i;
+ unsigned i, j;
int first;
pgoff_t next;
int pvec_pages, locked_pages;
@@ -894,7 +895,6 @@ get_more_pages:
if (!locked_pages)
goto release_pvec_pages;
if (i) {
- int j;
BUG_ON(!locked_pages || first < 0);
if (pvec_pages && i == pvec_pages &&
@@ -924,6 +924,10 @@ get_more_pages:
osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
!!pool, false);
+ for (j = 0; j < locked_pages; j++) {
+ struct page *page = pages[j];
+ ceph_writepage_to_fscache(inode, page);
+ }
pages = NULL; /* request message now owns the pages array */
pool = NULL;
diff --git a/fs/ceph/cache.c b/fs/ceph/cache.c
index 6bfe65e..6f928c4 100644
--- a/fs/ceph/cache.c
+++ b/fs/ceph/cache.c
@@ -320,6 +320,24 @@ void ceph_readpage_to_fscache(struct inode *inode, struct page *page)
fscache_uncache_page(ci->fscache, page);
}
+void ceph_writepage_to_fscache(struct inode *inode, struct page *page)
+{
+ struct ceph_inode_info *ci = ceph_inode(inode);
+ int ret;
+
+ if (!cache_valid(ci))
+ return;
+
+ if (!PageFsCache(page)) {
+ if (fscache_alloc_page(ci->fscache, page, GFP_KERNEL))
+ return;
+ }
+
+ if (fscache_write_page(ci->fscache, page, GFP_KERNEL))
+ fscache_uncache_page(ci->fscache, page);
+}
+
+
void ceph_invalidate_fscache_page(struct inode* inode, struct page *page)
{
struct ceph_inode_info *ci = ceph_inode(inode);
@@ -328,6 +346,17 @@ void ceph_invalidate_fscache_page(struct inode* inode, struct page *page)
fscache_uncache_page(ci->fscache, page);
}
+void ceph_maybe_release_fscache_page(struct inode *inode, struct page *page)
+{
+ struct ceph_inode_info *ci = ceph_inode(inode);
+
+ if (PageFsCache(page)) {
+ if (!fscache_check_page_write(ci->fscache, page))
+ fscache_maybe_release_page(ci->fscache,
+ page, GFP_KERNEL);
+ }
+}
+
void ceph_fscache_unregister_fs(struct ceph_fs_client* fsc)
{
if (fsc->revalidate_wq)
diff --git a/fs/ceph/cache.h b/fs/ceph/cache.h
index ba94940..aa02b7a 100644
--- a/fs/ceph/cache.h
+++ b/fs/ceph/cache.h
@@ -45,7 +45,9 @@ int ceph_readpages_from_fscache(struct inode *inode,
struct list_head *pages,
unsigned *nr_pages);
void ceph_readpage_to_fscache(struct inode *inode, struct page *page);
+void ceph_writepage_to_fscache(struct inode *inode, struct page *page);
void ceph_invalidate_fscache_page(struct inode* inode, struct page *page);
+void ceph_maybe_release_fscache_page(struct inode *inode, struct page *page);
void ceph_queue_revalidate(struct inode *inode);
static inline void ceph_fscache_invalidate(struct inode *inode)
@@ -127,6 +129,11 @@ static inline void ceph_readpage_to_fscache(struct inode *inode,
{
}
+static inline void ceph_writepage_to_fscache(struct inode *inode,
+ struct page *page)
+{
+}
+
static inline void ceph_fscache_invalidate(struct inode *inode)
{
}
@@ -140,6 +147,12 @@ static inline void ceph_fscache_unregister_inode_cookie(struct ceph_inode_info*
{
}
+
+static inline void ceph_maybe_release_fscache_page(struct inode *inode,
+ struct page *page)
+{
+}
+
static inline int ceph_release_fscache_page(struct page *page, gfp_t gfp)
{
return 1;
--
1.7.9.5
--
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