From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx120.postini.com [74.125.245.120]) by kanga.kvack.org (Postfix) with SMTP id 43FF36B0083 for ; Sat, 31 Mar 2012 05:29:24 -0400 (EDT) Received: by mail-bk0-f41.google.com with SMTP id q16so1494120bkw.14 for ; Sat, 31 Mar 2012 02:29:23 -0700 (PDT) Subject: [PATCH 4/7] mm: kill vma flag VM_INSERTPAGE From: Konstantin Khlebnikov Date: Sat, 31 Mar 2012 13:29:19 +0400 Message-ID: <20120331092919.19920.72179.stgit@zurg> In-Reply-To: <20120331091049.19373.28994.stgit@zurg> References: <20120331091049.19373.28994.stgit@zurg> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org, Andrew Morton , linux-kernel@vger.kernel.org Cc: Nick Piggin , Carsten Otte , Linus Torvalds , Peter Zijlstra This patch merges VM_INSERTPAGE into VM_MIXEDMAP (and moves it near to VM_PFNMAP). VM_MIXEDMAP vma anyway can mix pure-pfn ptes, special ptes and normal ptes. this patch side-effects: * copy_page_range() now always copies VM_MIXEDMAP vma on fork (why not?) * in case HAVE_PTE_SPECIAL appears non-special ptes in VM_MIXEDMAP vma. seems like all ok, all code ready for this. * in case !HAVE_PTE_SPECIAL: vm_normal_page() will check pfn_valid() after inserting pages via vm_insert_page() * small change in vma_wants_writenotify(), seems like do_wp_page() can handle this. Signed-off-by: Konstantin Khlebnikov Cc: Peter Zijlstra Cc: Nick Piggin Cc: Carsten Otte --- include/linux/mm.h | 3 +-- mm/huge_memory.c | 3 +-- mm/ksm.c | 2 +- mm/memory.c | 14 ++++++++++++-- mm/mmap.c | 2 +- 5 files changed, 16 insertions(+), 8 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 0dad037..553d134 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -84,6 +84,7 @@ extern unsigned int kobjsize(const void *objp); #define VM_MAYSHARE 0x00000080 #define VM_GROWSDOWN 0x00000100 /* general info on the segment */ +#define VM_MIXEDMAP 0x00000200 /* Can contain "struct page" and pure PFN pages */ #define VM_PFNMAP 0x00000400 /* Page-ranges managed without "struct page", just pure PFN */ #define VM_DENYWRITE 0x00000800 /* ETXTBSY on write attempts.. */ @@ -103,10 +104,8 @@ extern unsigned int kobjsize(const void *objp); #define VM_HUGETLB 0x00400000 /* Huge TLB Page VM */ #define VM_NONLINEAR 0x00800000 /* Is non-linear (remap_file_pages) */ #define VM_ARCH_1 0x01000000 /* Architecture-specific flag */ -#define VM_INSERTPAGE 0x02000000 /* The vma has had "vm_insert_page()" done on it */ #define VM_NODUMP 0x04000000 /* Do not include in the core dump */ -#define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */ #define VM_HUGEPAGE 0x20000000 /* MADV_HUGEPAGE marked this vma */ #define VM_NOHUGEPAGE 0x40000000 /* MADV_NOHUGEPAGE marked this vma */ #define VM_MERGEABLE 0x80000000 /* KSM may merge identical pages */ diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 6ea5477..65ed599 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1482,8 +1482,7 @@ out: return ret; } -#define VM_NO_THP (VM_SPECIAL|VM_INSERTPAGE|VM_MIXEDMAP| \ - VM_HUGETLB|VM_SHARED|VM_MAYSHARE) +#define VM_NO_THP (VM_SPECIAL|VM_MIXEDMAP|VM_HUGETLB|VM_SHARED|VM_MAYSHARE) int hugepage_madvise(struct vm_area_struct *vma, unsigned long *vm_flags, int advice) diff --git a/mm/ksm.c b/mm/ksm.c index d1cbe2a..f9ccb16 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -1469,7 +1469,7 @@ int ksm_madvise(struct vm_area_struct *vma, unsigned long start, */ if (*vm_flags & (VM_MERGEABLE | VM_SHARED | VM_MAYSHARE | VM_PFNMAP | VM_IO | VM_DONTEXPAND | - VM_RESERVED | VM_HUGETLB | VM_INSERTPAGE | + VM_RESERVED | VM_HUGETLB | VM_NONLINEAR | VM_MIXEDMAP)) return 0; /* just ignore the advice */ diff --git a/mm/memory.c b/mm/memory.c index e6e4dfd..9b8db37 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1043,7 +1043,8 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, * readonly mappings. The tradeoff is that copy_page_range is more * efficient than faulting. */ - if (!(vma->vm_flags & (VM_HUGETLB|VM_NONLINEAR|VM_PFNMAP|VM_INSERTPAGE))) { + if (!(vma->vm_flags & (VM_HUGETLB | VM_NONLINEAR | + VM_PFNMAP | VM_MIXEDMAP))) { if (!vma->anon_vma) return 0; } @@ -2068,6 +2069,11 @@ out: * ask for a shared writable mapping! * * The page does not need to be reserved. + * + * Usually this function is called from f_op->mmap() handler + * under mm->mmap_sem write-lock, so it can change vma->vm_flags. + * Caller must set VM_MIXEDMAP on vma if it wants to call this + * function from other places, for example from page-fault handler. */ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr, struct page *page) @@ -2076,7 +2082,11 @@ int vm_insert_page(struct vm_area_struct *vma, unsigned long addr, return -EFAULT; if (!page_count(page)) return -EINVAL; - vma->vm_flags |= VM_INSERTPAGE; + if (!(vma->vm_flags & VM_MIXEDMAP)) { + VM_BUG_ON(down_read_trylock(&vma->vm_mm->mmap_sem)); + VM_BUG_ON(vma->vm_flags & VM_PFNMAP); + vma->vm_flags |= VM_MIXEDMAP; + } return insert_page(vma, addr, page, vma->vm_page_prot); } EXPORT_SYMBOL(vm_insert_page); diff --git a/mm/mmap.c b/mm/mmap.c index 1a23d2c..3d254ca 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1177,7 +1177,7 @@ int vma_wants_writenotify(struct vm_area_struct *vma) return 0; /* Specialty mapping? */ - if (vm_flags & (VM_PFNMAP|VM_INSERTPAGE)) + if (vm_flags & VM_PFNMAP) return 0; /* Can the mapping track the dirty pages? */ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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