diff options
| author | Matthew Wilcox <willy@infradead.org> | 2018-02-01 01:17:36 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-01 02:18:37 +0100 |
| commit | 977fbdcd5986c9ff700bf276644d2b1973a53348 (patch) | |
| tree | 312bd6dd7f6a528759dad4b2da27eaf9ff339b12 /fs/dax.c | |
| parent | mm, userfaultfd, THP: avoid waiting when PMD under THP migration (diff) | |
| download | linux-977fbdcd5986c9ff700bf276644d2b1973a53348.tar.xz linux-977fbdcd5986c9ff700bf276644d2b1973a53348.zip | |
mm: add unmap_mapping_pages()
Several users of unmap_mapping_range() would prefer to express their
range in pages rather than bytes. Unfortuately, on a 32-bit kernel, you
have to remember to cast your page number to a 64-bit type before
shifting it, and four places in the current tree didn't remember to do
that. That's a sign of a bad interface.
Conveniently, unmap_mapping_range() actually converts from bytes into
pages, so hoist the guts of unmap_mapping_range() into a new function
unmap_mapping_pages() and convert the callers which want to use pages.
Link: http://lkml.kernel.org/r/20171206142627.GD32044@bombadil.infradead.org
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reported-by: "zhangyi (F)" <yi.zhang@huawei.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/dax.c')
| -rw-r--r-- | fs/dax.c | 19 |
1 files changed, 6 insertions, 13 deletions
@@ -44,6 +44,7 @@ /* The 'colour' (ie low bits) within a PMD of a page offset. */ #define PG_PMD_COLOUR ((PMD_SIZE >> PAGE_SHIFT) - 1) +#define PG_PMD_NR (PMD_SIZE >> PAGE_SHIFT) static wait_queue_head_t wait_table[DAX_WAIT_TABLE_ENTRIES]; @@ -375,8 +376,8 @@ restart: * unmapped. */ if (pmd_downgrade && dax_is_zero_entry(entry)) - unmap_mapping_range(mapping, - (index << PAGE_SHIFT) & PMD_MASK, PMD_SIZE, 0); + unmap_mapping_pages(mapping, index & ~PG_PMD_COLOUR, + PG_PMD_NR, false); err = radix_tree_preload( mapping_gfp_mask(mapping) & ~__GFP_HIGHMEM); @@ -538,12 +539,10 @@ static void *dax_insert_mapping_entry(struct address_space *mapping, if (dax_is_zero_entry(entry) && !(flags & RADIX_DAX_ZERO_PAGE)) { /* we are replacing a zero page with block mapping */ if (dax_is_pmd_entry(entry)) - unmap_mapping_range(mapping, - (vmf->pgoff << PAGE_SHIFT) & PMD_MASK, - PMD_SIZE, 0); + unmap_mapping_pages(mapping, index & ~PG_PMD_COLOUR, + PG_PMD_NR, false); else /* pte entry */ - unmap_mapping_range(mapping, vmf->pgoff << PAGE_SHIFT, - PAGE_SIZE, 0); + unmap_mapping_pages(mapping, vmf->pgoff, 1, false); } spin_lock_irq(&mapping->tree_lock); @@ -1269,12 +1268,6 @@ static int dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp, } #ifdef CONFIG_FS_DAX_PMD -/* - * The 'colour' (ie low bits) within a PMD of a page offset. This comes up - * more often than one might expect in the below functions. - */ -#define PG_PMD_COLOUR ((PMD_SIZE >> PAGE_SHIFT) - 1) - static int dax_pmd_load_hole(struct vm_fault *vmf, struct iomap *iomap, void *entry) { |