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author | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2012-08-13 15:39:10 -0400 |
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committer | Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2012-08-13 15:39:10 -0400 |
commit | 0980bd9cd32de2fef7eaa2858345c49d14498625 (patch) | |
tree | 41f5f823d0569a81b22037e79c22d823933a63f1 /mm/swap.c | |
parent | 78821b2c0299ab807d483802f09897728b93bce0 (diff) | |
parent | 0d7614f09c1ebdbaa1599a5aba7593f147bf96ee (diff) |
Merge commit 'v3.6-rc1' into linux-next
* commit 'v3.6-rc1': (9532 commits)
Linux 3.6-rc1
mm: remove node_start_pfn checking in new WARN_ON for now
ARM: mmp: add missing irqs.h
arm: mvebu: fix typo in .dtsi comment for Armada XP SoCs
ARM: PRIMA2: delete redundant codes to restore LATCHED when timer resumes
libceph: fix crypto key null deref, memory leak
ceph: simplify+fix atomic_open
sh: explicitly include sh_dma.h in setup-sh7722.c
um: Add arch/x86/um to MAINTAINERS
um: pass siginfo to guest process
um: fix ubd_file_size for read-only files
md/dm-raid: DM_RAID should select MD_RAID10
md/raid1: submit IO from originating thread instead of md thread.
raid5: raid5d handle stripe in batch way
raid5: make_request use batch stripe release
um: pull interrupt_end() into userspace()
um: split syscall_trace(), pass pt_regs to it
um: switch UPT_SET_RETURN_VALUE and regs_return_value to pt_regs
MIPS: Loongson 2: Sort out clock managment.
locks: remove unused lm_release_private
...
Diffstat (limited to 'mm/swap.c')
-rw-r--r-- | mm/swap.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/mm/swap.c b/mm/swap.c index 4e7e2ec67078..77825883298f 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -236,6 +236,58 @@ void put_pages_list(struct list_head *pages) } EXPORT_SYMBOL(put_pages_list); +/* + * get_kernel_pages() - pin kernel pages in memory + * @kiov: An array of struct kvec structures + * @nr_segs: number of segments to pin + * @write: pinning for read/write, currently ignored + * @pages: array that receives pointers to the pages pinned. + * Should be at least nr_segs long. + * + * Returns number of pages pinned. This may be fewer than the number + * requested. If nr_pages is 0 or negative, returns 0. If no pages + * were pinned, returns -errno. Each page returned must be released + * with a put_page() call when it is finished with. + */ +int get_kernel_pages(const struct kvec *kiov, int nr_segs, int write, + struct page **pages) +{ + int seg; + + for (seg = 0; seg < nr_segs; seg++) { + if (WARN_ON(kiov[seg].iov_len != PAGE_SIZE)) + return seg; + + pages[seg] = kmap_to_page(kiov[seg].iov_base); + page_cache_get(pages[seg]); + } + + return seg; +} +EXPORT_SYMBOL_GPL(get_kernel_pages); + +/* + * get_kernel_page() - pin a kernel page in memory + * @start: starting kernel address + * @write: pinning for read/write, currently ignored + * @pages: array that receives pointer to the page pinned. + * Must be at least nr_segs long. + * + * Returns 1 if page is pinned. If the page was not pinned, returns + * -errno. The page returned must be released with a put_page() call + * when it is finished with. + */ +int get_kernel_page(unsigned long start, int write, struct page **pages) +{ + const struct kvec kiov = { + .iov_base = (void *)start, + .iov_len = PAGE_SIZE + }; + + return get_kernel_pages(&kiov, 1, write, pages); +} +EXPORT_SYMBOL_GPL(get_kernel_page); + static void pagevec_lru_move_fn(struct pagevec *pvec, void (*move_fn)(struct page *page, struct lruvec *lruvec, void *arg), void *arg) |