The patch titled mm: introduce follow_pte() has been added to the -mm tree. Its filename is mm-introduce-follow_pte.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: mm: introduce follow_pte() From: Johannes Weiner <hannes@xxxxxxxxxxx> A generic readonly page table lookup helper to map an address space and an address from it to a pte. Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: Magnus Damm <magnus.damm@xxxxxxxxx> Cc: Hans Verkuil <hverkuil@xxxxxxxxx> Cc: Paul Mundt <lethal@xxxxxxxxxxxx> Cc: Hugh Dickins <hugh@xxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff -puN mm/memory.c~mm-introduce-follow_pte mm/memory.c --- a/mm/memory.c~mm-introduce-follow_pte +++ a/mm/memory.c @@ -3191,6 +3191,43 @@ int in_gate_area_no_task(unsigned long a #endif /* __HAVE_ARCH_GATE_AREA */ +static int follow_pte(struct mm_struct *mm, unsigned long address, + pte_t **ptepp, spinlock_t **ptlp) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *ptep; + + pgd = pgd_offset(mm, address); + if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd))) + goto out; + + pud = pud_offset(pgd, address); + if (pud_none(*pud) || unlikely(pud_bad(*pud))) + goto out; + + pmd = pmd_offset(pud, address); + if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd))) + goto out; + + /* We cannot handle huge page PFN maps. Luckily they don't exist. */ + if (pmd_huge(*pmd)) + goto out; + + ptep = pte_offset_map_lock(mm, pmd, address, ptlp); + if (!ptep) + goto out; + if (!pte_present(*ptep)) + goto unlock; + *ptepp = ptep; + return 0; +unlock: + pte_unmap_unlock(ptep, *ptlp); +out: + return -EINVAL; +} + #ifdef CONFIG_HAVE_IOREMAP_PROT int follow_phys(struct vm_area_struct *vma, unsigned long address, unsigned int flags, _ Patches currently in -mm which might be from hannes@xxxxxxxxxxx are origin.patch linux-next.patch eliminate-thousands-of-warnings-with-gcc-32-build.patch eliminate-thousands-of-warnings-with-gcc-32-build-cleanup.patch mm-page-writebackc-dirty-limit-type-should-be-unsigned-long.patch vmscan-evict-use-once-pages-first-v3.patch mm-introduce-follow_pte.patch mm-use-generic-follow_pte-in-follow_phys.patch mm-introduce-follow_pfn.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html