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authorIngo Molnar <mingo@elte.hu>2010-03-22 18:46:57 +0100
committerIngo Molnar <mingo@elte.hu>2010-03-22 18:47:01 +0100
commitd2f1e15b661e71fd52111f51c99a6ce41384e9ef (patch)
tree8731e7e772e6f825ebbc6eef7681bc46302149bd /fs/ceph/pagelist.c
parent40b7e05e17eef31ff30fe08dfc2424ef653a792c (diff)
parent220bf991b0366cc50a94feede3d7341fa5710ee4 (diff)
Merge commit 'v2.6.34-rc2' into perf/core
Merge reason: Pick up latest perf fixes from upstream. Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'fs/ceph/pagelist.c')
-rw-r--r--fs/ceph/pagelist.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/fs/ceph/pagelist.c b/fs/ceph/pagelist.c
new file mode 100644
index 00000000000..370e9369547
--- /dev/null
+++ b/fs/ceph/pagelist.c
@@ -0,0 +1,54 @@
+
+#include <linux/pagemap.h>
+#include <linux/highmem.h>
+
+#include "pagelist.h"
+
+int ceph_pagelist_release(struct ceph_pagelist *pl)
+{
+ if (pl->mapped_tail)
+ kunmap(pl->mapped_tail);
+ while (!list_empty(&pl->head)) {
+ struct page *page = list_first_entry(&pl->head, struct page,
+ lru);
+ list_del(&page->lru);
+ __free_page(page);
+ }
+ return 0;
+}
+
+static int ceph_pagelist_addpage(struct ceph_pagelist *pl)
+{
+ struct page *page = alloc_page(GFP_NOFS);
+ if (!page)
+ return -ENOMEM;
+ pl->room += PAGE_SIZE;
+ list_add_tail(&page->lru, &pl->head);
+ if (pl->mapped_tail)
+ kunmap(pl->mapped_tail);
+ pl->mapped_tail = kmap(page);
+ return 0;
+}
+
+int ceph_pagelist_append(struct ceph_pagelist *pl, void *buf, size_t len)
+{
+ while (pl->room < len) {
+ size_t bit = pl->room;
+ int ret;
+
+ memcpy(pl->mapped_tail + (pl->length & ~PAGE_CACHE_MASK),
+ buf, bit);
+ pl->length += bit;
+ pl->room -= bit;
+ buf += bit;
+ len -= bit;
+ ret = ceph_pagelist_addpage(pl);
+ if (ret)
+ return ret;
+ }
+
+ memcpy(pl->mapped_tail + (pl->length & ~PAGE_CACHE_MASK), buf, len);
+ pl->length += len;
+ pl->room -= len;
+ return 0;
+}