We were a little sloppy about using PAGE_SIZE instead of PAGE_CACHE_SIZE. The important thing to remember is that the VM is gicing us a pgoff_t and asking us to populate that. If PAGE_CACHE_SIZE were larger than PAGE_SIZE, then we would not successfully fill in the PTEs for faults that occurred in the upper portions of PAGE_CACHE_SIZE.
Of course, we actually only fill in one PTE, so this still doesn't solve the problem. I have my doubts we will ever increase PAGE_CACHE_SIZE now that we have map_pages. Signed-off-by: Matthew Wilcox <[email protected]> --- fs/dax.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) diff --git a/fs/dax.c b/fs/dax.c index d0e1334..f0c204d 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -558,14 +558,14 @@ static int dax_pte_fault(struct vm_area_struct *vma, struct vm_fault *vmf, int error; int major = 0; - size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT; + size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; if (vmf->pgoff >= size) return VM_FAULT_SIGBUS; memset(&bh, 0, sizeof(bh)); - block = (sector_t)vmf->pgoff << (PAGE_SHIFT - blkbits); + block = (sector_t)vmf->pgoff << (PAGE_CACHE_SHIFT - blkbits); bh.b_bdev = inode->i_sb->s_bdev; - bh.b_size = PAGE_SIZE; + bh.b_size = PAGE_CACHE_SIZE; repeat: page = find_get_page(mapping, vmf->pgoff); @@ -582,7 +582,7 @@ static int dax_pte_fault(struct vm_area_struct *vma, struct vm_fault *vmf, } error = get_block(inode, block, &bh, 0); - if (!error && (bh.b_size < PAGE_SIZE)) + if (!error && (bh.b_size < PAGE_CACHE_SIZE)) error = -EIO; /* fs corruption? */ if (error) goto unlock_page; @@ -593,7 +593,7 @@ static int dax_pte_fault(struct vm_area_struct *vma, struct vm_fault *vmf, count_vm_event(PGMAJFAULT); mem_cgroup_count_vm_event(vma->vm_mm, PGMAJFAULT); major = VM_FAULT_MAJOR; - if (!error && (bh.b_size < PAGE_SIZE)) + if (!error && (bh.b_size < PAGE_CACHE_SIZE)) error = -EIO; if (error) goto unlock_page; @@ -630,7 +630,7 @@ static int dax_pte_fault(struct vm_area_struct *vma, struct vm_fault *vmf, page = find_lock_page(mapping, vmf->pgoff); if (page) { - unmap_mapping_range(mapping, vmf->pgoff << PAGE_SHIFT, + unmap_mapping_range(mapping, vmf->pgoff << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE, 0); delete_from_page_cache(page); unlock_page(page); @@ -677,7 +677,7 @@ static int dax_pte_fault(struct vm_area_struct *vma, struct vm_fault *vmf, * The 'colour' (ie low bits) within a PMD of a page offset. This comes up * more often than one might expect in the below function. */ -#define PG_PMD_COLOUR ((PMD_SIZE >> PAGE_SHIFT) - 1) +#define PG_PMD_COLOUR ((PMD_SIZE >> PAGE_CACHE_SHIFT) - 1) static void __dax_dbg(struct buffer_head *bh, unsigned long address, const char *reason, const char *fn) @@ -734,7 +734,7 @@ static int dax_pmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf, return VM_FAULT_FALLBACK; } - size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT; + size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; if (vmf->pgoff >= size) return VM_FAULT_SIGBUS; /* If the PMD would cover blocks out of the file */ @@ -746,7 +746,7 @@ static int dax_pmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf, memset(&bh, 0, sizeof(bh)); bh.b_bdev = inode->i_sb->s_bdev; - block = (sector_t)vmf->pgoff << (PAGE_SHIFT - blkbits); + block = (sector_t)vmf->pgoff << (PAGE_CACHE_SHIFT - blkbits); bh.b_size = PMD_SIZE; @@ -776,7 +776,7 @@ static int dax_pmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf, * zero pages covering this hole */ if (alloc) { - loff_t lstart = vmf->pgoff << PAGE_SHIFT; + loff_t lstart = vmf->pgoff << PAGE_CACHE_SHIFT; loff_t lend = lstart + PMD_SIZE - 1; /* inclusive */ truncate_pagecache_range(inode, lstart, lend); @@ -904,7 +904,7 @@ static int dax_pmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf, * The 'colour' (ie low bits) within a PUD of a page offset. This comes up * more often than one might expect in the below function. */ -#define PG_PUD_COLOUR ((PUD_SIZE >> PAGE_SHIFT) - 1) +#define PG_PUD_COLOUR ((PUD_SIZE >> PAGE_CACHE_SHIFT) - 1) #define dax_pud_dbg(bh, address, reason) __dax_dbg(bh, address, reason, "dax_pud") @@ -945,7 +945,7 @@ static int dax_pud_fault(struct vm_area_struct *vma, struct vm_fault *vmf, return VM_FAULT_FALLBACK; } - size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT; + size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; if (vmf->pgoff >= size) return VM_FAULT_SIGBUS; /* If the PUD would cover blocks out of the file */ @@ -957,7 +957,7 @@ static int dax_pud_fault(struct vm_area_struct *vma, struct vm_fault *vmf, memset(&bh, 0, sizeof(bh)); bh.b_bdev = inode->i_sb->s_bdev; - block = (sector_t)vmf->pgoff << (PAGE_SHIFT - blkbits); + block = (sector_t)vmf->pgoff << (PAGE_CACHE_SHIFT - blkbits); bh.b_size = PUD_SIZE; @@ -987,7 +987,7 @@ static int dax_pud_fault(struct vm_area_struct *vma, struct vm_fault *vmf, * zero pages covering this hole */ if (alloc) { - loff_t lstart = vmf->pgoff << PAGE_SHIFT; + loff_t lstart = vmf->pgoff << PAGE_CACHE_SHIFT; loff_t lend = lstart + PUD_SIZE - 1; /* inclusive */ truncate_pagecache_range(inode, lstart, lend); -- 2.7.0.rc3
