From 795cac72e902496adac399389f9affe5d1ab821a Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Mon, 23 Apr 2012 15:58:53 +1000 Subject: [PATCH] xfs: kill xfs_buf_btoc xfs_buf_btoc and friends are simple macros that do basic block to page index conversion and vice versa. These aren't widely used, and we use open coded masking and shifting everywhere else. Hence remove the macros and open code the work they do. Also, use of PAGE_CACHE_{SIZE|SHIFT|MASK} for these macros is now incorrect - we are using pages directly and not the page cache, so use PAGE_{SIZE|MASK|SHIFT} instead. Signed-off-by: Dave Chinner Reviewed-by: Christoph Hellwig Reviewed-by: Mark Tinguely Signed-off-by: Ben Myers --- fs/xfs/xfs_buf.c | 39 +++++++++++++++++++++------------------ fs/xfs/xfs_buf.h | 5 ----- 2 files changed, 21 insertions(+), 23 deletions(-) diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index ab3c4491777b..942cf5051ab4 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -306,7 +306,7 @@ xfs_buf_allocate_memory( size_t nbytes, offset; gfp_t gfp_mask = xb_to_gfp(flags); unsigned short page_count, i; - xfs_off_t end; + xfs_off_t start, end; int error; /* @@ -314,15 +314,15 @@ xfs_buf_allocate_memory( * the memory from the heap - there's no need for the complexity of * page arrays to keep allocation down to order 0. */ - if (bp->b_length < BTOBB(PAGE_SIZE)) { - bp->b_addr = kmem_alloc(BBTOB(bp->b_length), xb_to_km(flags)); + size = BBTOB(bp->b_length); + if (size < PAGE_SIZE) { + bp->b_addr = kmem_alloc(size, xb_to_km(flags)); if (!bp->b_addr) { /* low memory - use alloc_page loop instead */ goto use_alloc_page; } - if (((unsigned long)(bp->b_addr + BBTOB(bp->b_length) - 1) & - PAGE_MASK) != + if (((unsigned long)(bp->b_addr + size - 1) & PAGE_MASK) != ((unsigned long)bp->b_addr & PAGE_MASK)) { /* b_addr spans two pages - use alloc_page instead */ kmem_free(bp->b_addr); @@ -338,14 +338,14 @@ xfs_buf_allocate_memory( } use_alloc_page: - end = BBTOB(bp->b_bn + bp->b_length); - page_count = xfs_buf_btoc(end) - xfs_buf_btoct(BBTOB(bp->b_bn)); + start = BBTOB(bp->b_bn) >> PAGE_SHIFT; + end = (BBTOB(bp->b_bn + bp->b_length) + PAGE_SIZE - 1) >> PAGE_SHIFT; + page_count = end - start; error = _xfs_buf_get_pages(bp, page_count, flags); if (unlikely(error)) return error; offset = bp->b_offset; - size = BBTOB(bp->b_length); bp->b_flags |= _XBF_PAGES; for (i = 0; i < bp->b_page_count; i++) { @@ -1320,27 +1320,30 @@ xfs_buf_iomove( void *data, /* data address */ xfs_buf_rw_t mode) /* read/write/zero flag */ { - size_t bend, cpoff, csize; - struct page *page; + size_t bend; bend = boff + bsize; while (boff < bend) { - page = bp->b_pages[xfs_buf_btoct(boff + bp->b_offset)]; - cpoff = xfs_buf_poff(boff + bp->b_offset); - csize = min_t(size_t, - PAGE_SIZE - cpoff, BBTOB(bp->b_io_length) - boff); + struct page *page; + int page_index, page_offset, csize; - ASSERT(((csize + cpoff) <= PAGE_SIZE)); + page_index = (boff + bp->b_offset) >> PAGE_SHIFT; + page_offset = (boff + bp->b_offset) & ~PAGE_MASK; + page = bp->b_pages[page_index]; + csize = min_t(size_t, PAGE_SIZE - page_offset, + BBTOB(bp->b_io_length) - boff); + + ASSERT((csize + page_offset) <= PAGE_SIZE); switch (mode) { case XBRW_ZERO: - memset(page_address(page) + cpoff, 0, csize); + memset(page_address(page) + page_offset, 0, csize); break; case XBRW_READ: - memcpy(data, page_address(page) + cpoff, csize); + memcpy(data, page_address(page) + page_offset, csize); break; case XBRW_WRITE: - memcpy(page_address(page) + cpoff, data, csize); + memcpy(page_address(page) + page_offset, data, csize); } boff += csize; diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h index 9787645fa54c..5b048f7d13ea 100644 --- a/fs/xfs/xfs_buf.h +++ b/fs/xfs/xfs_buf.h @@ -32,11 +32,6 @@ #define XFS_BUF_DADDR_NULL ((xfs_daddr_t) (-1LL)) -#define xfs_buf_ctob(pp) ((pp) * PAGE_CACHE_SIZE) -#define xfs_buf_btoc(dd) (((dd) + PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT) -#define xfs_buf_btoct(dd) ((dd) >> PAGE_CACHE_SHIFT) -#define xfs_buf_poff(aa) ((aa) & ~PAGE_CACHE_MASK) - typedef enum { XBRW_READ = 1, /* transfer into target memory */ XBRW_WRITE = 2, /* transfer from target memory */