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author | Boaz Harrosh <bharrosh@panasas.com> | 2010-01-28 16:24:06 (GMT) |
---|---|---|
committer | Boaz Harrosh <bharrosh@panasas.com> | 2010-02-28 11:44:42 (GMT) |
commit | 86093aaff5be5b214613eb60553e236bdb389c84 (patch) | |
tree | 64993f3fff8b60408441e8912aa5690346108492 /fs/exofs/inode.c | |
parent | 5d952b8391692553c31e620a92d6e09262a9a307 (diff) | |
download | linux-86093aaff5be5b214613eb60553e236bdb389c84.tar.xz |
exofs: convert io_state to use pages array instead of bio at input
* inode.c operations are full-pages based, and not actually
true scatter-gather
* Lets us use more pages at once upto 512 (from 249) in 64 bit
* Brings us much much closer to be able to use exofs's io_state engine
from objlayout driver. (Once I decide where to put the common code)
After RAID0 patch the outer (input) bio was never used as a bio, but
was simply a page carrier into the raid engine. Even in the simple
mirror/single-dev arrangement pages info was copied into a second bio.
It is now easer to just pass a pages array into the io_state and prepare
bio(s) once.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Diffstat (limited to 'fs/exofs/inode.c')
-rw-r--r-- | fs/exofs/inode.c | 81 |
1 files changed, 41 insertions, 40 deletions
diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c index 2b3163e..6ca0b01 100644 --- a/fs/exofs/inode.c +++ b/fs/exofs/inode.c @@ -41,16 +41,18 @@ enum { BIO_MAX_PAGES_KMALLOC = (PAGE_SIZE - sizeof(struct bio)) / sizeof(struct bio_vec), + MAX_PAGES_KMALLOC = + PAGE_SIZE / sizeof(struct page *), }; struct page_collect { struct exofs_sb_info *sbi; - struct request_queue *req_q; struct inode *inode; unsigned expected_pages; struct exofs_io_state *ios; - struct bio *bio; + struct page **pages; + unsigned alloc_pages; unsigned nr_pages; unsigned long length; loff_t pg_first; /* keep 64bit also in 32-arches */ @@ -62,15 +64,12 @@ static void _pcol_init(struct page_collect *pcol, unsigned expected_pages, struct exofs_sb_info *sbi = inode->i_sb->s_fs_info; pcol->sbi = sbi; - /* Create master bios on first Q, later on cloning, each clone will be - * allocated on it's destination Q - */ - pcol->req_q = osd_request_queue(sbi->layout.s_ods[0]); pcol->inode = inode; pcol->expected_pages = expected_pages; pcol->ios = NULL; - pcol->bio = NULL; + pcol->pages = NULL; + pcol->alloc_pages = 0; pcol->nr_pages = 0; pcol->length = 0; pcol->pg_first = -1; @@ -80,7 +79,8 @@ static void _pcol_reset(struct page_collect *pcol) { pcol->expected_pages -= min(pcol->nr_pages, pcol->expected_pages); - pcol->bio = NULL; + pcol->pages = NULL; + pcol->alloc_pages = 0; pcol->nr_pages = 0; pcol->length = 0; pcol->pg_first = -1; @@ -90,13 +90,13 @@ static void _pcol_reset(struct page_collect *pcol) * it might not end here. don't be left with nothing */ if (!pcol->expected_pages) - pcol->expected_pages = BIO_MAX_PAGES_KMALLOC; + pcol->expected_pages = MAX_PAGES_KMALLOC; } static int pcol_try_alloc(struct page_collect *pcol) { - int pages = min_t(unsigned, pcol->expected_pages, - BIO_MAX_PAGES_KMALLOC); + unsigned pages = min_t(unsigned, pcol->expected_pages, + MAX_PAGES_KMALLOC); if (!pcol->ios) { /* First time allocate io_state */ int ret = exofs_get_io_state(&pcol->sbi->layout, &pcol->ios); @@ -105,23 +105,28 @@ static int pcol_try_alloc(struct page_collect *pcol) return ret; } + /* TODO: easily support bio chaining */ + pages = min_t(unsigned, pages, + pcol->sbi->layout.group_width * BIO_MAX_PAGES_KMALLOC); + for (; pages; pages >>= 1) { - pcol->bio = bio_kmalloc(GFP_KERNEL, pages); - if (likely(pcol->bio)) + pcol->pages = kmalloc(pages * sizeof(struct page *), + GFP_KERNEL); + if (likely(pcol->pages)) { + pcol->alloc_pages = pages; return 0; + } } - EXOFS_ERR("Failed to bio_kmalloc expected_pages=%u\n", + EXOFS_ERR("Failed to kmalloc expected_pages=%u\n", pcol->expected_pages); return -ENOMEM; } static void pcol_free(struct page_collect *pcol) { - if (pcol->bio) { - bio_put(pcol->bio); - pcol->bio = NULL; - } + kfree(pcol->pages); + pcol->pages = NULL; if (pcol->ios) { exofs_put_io_state(pcol->ios); @@ -132,11 +137,10 @@ static void pcol_free(struct page_collect *pcol) static int pcol_add_page(struct page_collect *pcol, struct page *page, unsigned len) { - int added_len = bio_add_pc_page(pcol->req_q, pcol->bio, page, len, 0); - if (unlikely(len != added_len)) + if (unlikely(pcol->nr_pages >= pcol->alloc_pages)) return -ENOMEM; - ++pcol->nr_pages; + pcol->pages[pcol->nr_pages++] = page; pcol->length += len; return 0; } @@ -181,7 +185,6 @@ static void update_write_page(struct page *page, int ret) */ static int __readpages_done(struct page_collect *pcol, bool do_unlock) { - struct bio_vec *bvec; int i; u64 resid; u64 good_bytes; @@ -198,8 +201,8 @@ static int __readpages_done(struct page_collect *pcol, bool do_unlock) pcol->inode->i_ino, _LLU(good_bytes), pcol->length, pcol->nr_pages); - __bio_for_each_segment(bvec, pcol->bio, i, 0) { - struct page *page = bvec->bv_page; + for (i = 0; i < pcol->nr_pages; i++) { + struct page *page = pcol->pages[i]; struct inode *inode = page->mapping->host; int page_stat; @@ -218,7 +221,7 @@ static int __readpages_done(struct page_collect *pcol, bool do_unlock) ret = update_read_page(page, page_stat); if (do_unlock) unlock_page(page); - length += bvec->bv_len; + length += PAGE_SIZE; } pcol_free(pcol); @@ -238,11 +241,10 @@ static void readpages_done(struct exofs_io_state *ios, void *p) static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw) { - struct bio_vec *bvec; int i; - __bio_for_each_segment(bvec, pcol->bio, i, 0) { - struct page *page = bvec->bv_page; + for (i = 0; i < pcol->nr_pages; i++) { + struct page *page = pcol->pages[i]; if (rw == READ) update_read_page(page, ret); @@ -260,13 +262,14 @@ static int read_exec(struct page_collect *pcol, bool is_sync) struct page_collect *pcol_copy = NULL; int ret; - if (!pcol->bio) + if (!pcol->pages) return 0; /* see comment in _readpage() about sync reads */ WARN_ON(is_sync && (pcol->nr_pages != 1)); - ios->bio = pcol->bio; + ios->pages = pcol->pages; + ios->nr_pages = pcol->nr_pages; ios->length = pcol->length; ios->offset = pcol->pg_first << PAGE_CACHE_SHIFT; @@ -366,7 +369,7 @@ try_again: goto try_again; } - if (!pcol->bio) { + if (!pcol->pages) { ret = pcol_try_alloc(pcol); if (unlikely(ret)) goto fail; @@ -448,7 +451,6 @@ static int exofs_readpage(struct file *file, struct page *page) static void writepages_done(struct exofs_io_state *ios, void *p) { struct page_collect *pcol = p; - struct bio_vec *bvec; int i; u64 resid; u64 good_bytes; @@ -467,8 +469,8 @@ static void writepages_done(struct exofs_io_state *ios, void *p) pcol->inode->i_ino, _LLU(good_bytes), pcol->length, pcol->nr_pages); - __bio_for_each_segment(bvec, pcol->bio, i, 0) { - struct page *page = bvec->bv_page; + for (i = 0; i < pcol->nr_pages; i++) { + struct page *page = pcol->pages[i]; struct inode *inode = page->mapping->host; int page_stat; @@ -485,7 +487,7 @@ static void writepages_done(struct exofs_io_state *ios, void *p) EXOFS_DBGMSG2(" writepages_done(0x%lx, 0x%lx) status=%d\n", inode->i_ino, page->index, page_stat); - length += bvec->bv_len; + length += PAGE_SIZE; } pcol_free(pcol); @@ -500,7 +502,7 @@ static int write_exec(struct page_collect *pcol) struct page_collect *pcol_copy = NULL; int ret; - if (!pcol->bio) + if (!pcol->pages) return 0; pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL); @@ -512,9 +514,8 @@ static int write_exec(struct page_collect *pcol) *pcol_copy = *pcol; - pcol_copy->bio->bi_rw |= (1 << BIO_RW); /* FIXME: bio_set_dir() */ - - ios->bio = pcol_copy->bio; + ios->pages = pcol_copy->pages; + ios->nr_pages = pcol_copy->nr_pages; ios->offset = pcol_copy->pg_first << PAGE_CACHE_SHIFT; ios->length = pcol_copy->length; ios->done = writepages_done; @@ -605,7 +606,7 @@ try_again: goto try_again; } - if (!pcol->bio) { + if (!pcol->pages) { ret = pcol_try_alloc(pcol); if (unlikely(ret)) goto fail; |