Commit | Line | Data |
---|---|---|
58bb3b37 | 1 | |
5a0e3ad6 | 2 | #include <linux/gfp.h> |
58bb3b37 SW |
3 | #include <linux/pagemap.h> |
4 | #include <linux/highmem.h> | |
5 | ||
6 | #include "pagelist.h" | |
7 | ||
3d4401d9 YS |
8 | static void ceph_pagelist_unmap_tail(struct ceph_pagelist *pl) |
9 | { | |
10 | struct page *page = list_entry(pl->head.prev, struct page, | |
11 | lru); | |
12 | kunmap(page); | |
13 | } | |
14 | ||
58bb3b37 SW |
15 | int ceph_pagelist_release(struct ceph_pagelist *pl) |
16 | { | |
17 | if (pl->mapped_tail) | |
3d4401d9 YS |
18 | ceph_pagelist_unmap_tail(pl); |
19 | ||
58bb3b37 SW |
20 | while (!list_empty(&pl->head)) { |
21 | struct page *page = list_first_entry(&pl->head, struct page, | |
22 | lru); | |
23 | list_del(&page->lru); | |
24 | __free_page(page); | |
25 | } | |
26 | return 0; | |
27 | } | |
28 | ||
29 | static int ceph_pagelist_addpage(struct ceph_pagelist *pl) | |
30 | { | |
31459fe4 | 31 | struct page *page = __page_cache_alloc(GFP_NOFS); |
58bb3b37 SW |
32 | if (!page) |
33 | return -ENOMEM; | |
34 | pl->room += PAGE_SIZE; | |
35 | list_add_tail(&page->lru, &pl->head); | |
36 | if (pl->mapped_tail) | |
3d4401d9 | 37 | ceph_pagelist_unmap_tail(pl); |
58bb3b37 SW |
38 | pl->mapped_tail = kmap(page); |
39 | return 0; | |
40 | } | |
41 | ||
42 | int ceph_pagelist_append(struct ceph_pagelist *pl, void *buf, size_t len) | |
43 | { | |
44 | while (pl->room < len) { | |
45 | size_t bit = pl->room; | |
46 | int ret; | |
47 | ||
48 | memcpy(pl->mapped_tail + (pl->length & ~PAGE_CACHE_MASK), | |
49 | buf, bit); | |
50 | pl->length += bit; | |
51 | pl->room -= bit; | |
52 | buf += bit; | |
53 | len -= bit; | |
54 | ret = ceph_pagelist_addpage(pl); | |
55 | if (ret) | |
56 | return ret; | |
57 | } | |
58 | ||
59 | memcpy(pl->mapped_tail + (pl->length & ~PAGE_CACHE_MASK), buf, len); | |
60 | pl->length += len; | |
61 | pl->room -= len; | |
62 | return 0; | |
63 | } |