diff options
author | Chris Mason <chris.mason@oracle.com> | 2007-11-08 18:59:22 +0300 |
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committer | Chris Mason <chris.mason@oracle.com> | 2008-09-25 19:03:57 +0400 |
commit | 3ab2fb5a8cb003897016b6eb38ddad916226c1b2 (patch) | |
tree | dce5ac7ae586111c7e872193c09ced717b936549 /fs/btrfs/extent_map.c | |
parent | 856bf3e592f917e7d663cb7fa93e83fe795e8f4e (diff) | |
download | linux-3ab2fb5a8cb003897016b6eb38ddad916226c1b2.tar.xz |
Btrfs: Add readpages support
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/extent_map.c')
-rw-r--r-- | fs/btrfs/extent_map.c | 70 |
1 files changed, 63 insertions, 7 deletions
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index 754bc42c162a..0077c6c1d9f9 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -11,6 +11,7 @@ #include <linux/swap.h> #include <linux/version.h> #include <linux/writeback.h> +#include <linux/pagevec.h> #include "extent_map.h" /* temporary define until extent_map moves out of btrfs */ @@ -1503,7 +1504,7 @@ static int submit_extent_page(int rw, struct extent_map_tree *tree, size_t size, unsigned long offset, struct block_device *bdev, struct bio **bio_ret, - int max_pages, + unsigned long max_pages, bio_end_io_t end_io_func) { int ret = 0; @@ -1520,7 +1521,7 @@ static int submit_extent_page(int rw, struct extent_map_tree *tree, return 0; } } - nr = min(max_pages, bio_get_nr_vecs(bdev)); + nr = min_t(int, max_pages, bio_get_nr_vecs(bdev)); bio = extent_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH); if (!bio) { printk("failed to allocate bio nr %d\n", nr); @@ -1552,8 +1553,10 @@ void set_page_extent_mapped(struct page *page) * into the tree that are removed when the IO is done (by the end_io * handlers) */ -int extent_read_full_page(struct extent_map_tree *tree, struct page *page, - get_extent_t *get_extent) +static int __extent_read_full_page(struct extent_map_tree *tree, + struct page *page, + get_extent_t *get_extent, + struct bio **bio) { struct inode *inode = page->mapping->host; u64 start = (u64)page->index << PAGE_CACHE_SHIFT; @@ -1631,10 +1634,12 @@ int extent_read_full_page(struct extent_map_tree *tree, struct page *page, cur + iosize - 1); } if (!ret) { + unsigned long nr = (last_byte >> PAGE_CACHE_SHIFT) + 1; + nr -= page->index; ret = submit_extent_page(READ, tree, page, - sector, iosize, page_offset, - bdev, NULL, 1, - end_bio_extent_readpage); + sector, iosize, page_offset, + bdev, bio, nr, + end_bio_extent_readpage); } if (ret) SetPageError(page); @@ -1649,6 +1654,18 @@ int extent_read_full_page(struct extent_map_tree *tree, struct page *page, } return 0; } + +int extent_read_full_page(struct extent_map_tree *tree, struct page *page, + get_extent_t *get_extent) +{ + struct bio *bio = NULL; + int ret; + + ret = __extent_read_full_page(tree, page, get_extent, &bio); + if (bio) + submit_one_bio(READ, bio); + return ret; +} EXPORT_SYMBOL(extent_read_full_page); /* @@ -1836,6 +1853,45 @@ int extent_writepages(struct extent_map_tree *tree, } EXPORT_SYMBOL(extent_writepages); +int extent_readpages(struct extent_map_tree *tree, + struct address_space *mapping, + struct list_head *pages, unsigned nr_pages, + get_extent_t get_extent) +{ + struct bio *bio = NULL; + unsigned page_idx; + struct pagevec pvec; + + pagevec_init(&pvec, 0); + for (page_idx = 0; page_idx < nr_pages; page_idx++) { + struct page *page = list_entry(pages->prev, struct page, lru); + + prefetchw(&page->flags); + list_del(&page->lru); + /* + * what we want to do here is call add_to_page_cache_lru, + * but that isn't exported, so we reproduce it here + */ + if (!add_to_page_cache(page, mapping, + page->index, GFP_KERNEL)) { + + /* open coding of lru_cache_add, also not exported */ + page_cache_get(page); + if (!pagevec_add(&pvec, page)) + __pagevec_lru_add(&pvec); + __extent_read_full_page(tree, page, get_extent, &bio); + } + page_cache_release(page); + } + if (pagevec_count(&pvec)) + __pagevec_lru_add(&pvec); + BUG_ON(!list_empty(pages)); + if (bio) + submit_one_bio(READ, bio); + return 0; +} +EXPORT_SYMBOL(extent_readpages); + /* * basic invalidatepage code, this waits on any locked or writeback * ranges corresponding to the page, and then deletes any extent state |