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| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2017-03-16 18:26:50 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-03-18 09:48:01 +0100 |
| commit | e7884f8ead4a301b04687a3238527b06feef8ea0 (patch) | |
| tree | 7a1460bae65463fb8eaff1dc853779ca6b3265d6 /mm | |
| parent | 9a804fecee232e71b47ac37d62fd3d5d66b08b91 (diff) | |
| download | linux-e7884f8ead4a301b04687a3238527b06feef8ea0.tar.gz linux-e7884f8ead4a301b04687a3238527b06feef8ea0.tar.bz2 linux-e7884f8ead4a301b04687a3238527b06feef8ea0.zip | |
mm/gup: Move permission checks into helpers
This is a preparation patch for the transition of x86 to the generic GUP_fast()
implementation.
On x86, we would need to do additional permission checks to determine if
access is allowed.
Let's abstract it out into separate helpers.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aneesh Kumar K . V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170316152655.37789-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/gup.c | 15 |
1 files changed, 10 insertions, 5 deletions
@@ -1212,8 +1212,13 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, * Similar to the PMD case below, NUMA hinting must take slow * path using the pte_protnone check. */ - if (!pte_present(pte) || pte_special(pte) || - pte_protnone(pte) || (write && !pte_write(pte))) + if (pte_protnone(pte)) + goto pte_unmap; + + if (!pte_access_permitted(pte, write)) + goto pte_unmap; + + if (pte_special(pte)) goto pte_unmap; VM_BUG_ON(!pfn_valid(pte_pfn(pte))); @@ -1264,7 +1269,7 @@ static int gup_huge_pmd(pmd_t orig, pmd_t *pmdp, unsigned long addr, struct page *head, *page; int refs; - if (write && !pmd_write(orig)) + if (!pmd_access_permitted(orig, write)) return 0; refs = 0; @@ -1299,7 +1304,7 @@ static int gup_huge_pud(pud_t orig, pud_t *pudp, unsigned long addr, struct page *head, *page; int refs; - if (write && !pud_write(orig)) + if (!pud_access_permitted(orig, write)) return 0; refs = 0; @@ -1335,7 +1340,7 @@ static int gup_huge_pgd(pgd_t orig, pgd_t *pgdp, unsigned long addr, int refs; struct page *head, *page; - if (write && !pgd_write(orig)) + if (!pgd_access_permitted(orig, write)) return 0; refs = 0; |