Messages in this thread Patch in this message |  | | | Subject | [patch 06/18] remap_file_pages protection support: support private vma for MAP_POPULATE | | From | blaisorblade@yahoo ... | | Date | Fri, 26 Aug 2005 18:53:17 +0200 |
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From: Ingo Molnar <mingo@elte.hu>
Fix MAP_POPULATE | MAP_PRIVATE. We don't need the VMA to be shared if we don't rearrange pages around. And it's trivial to do. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> --- linux-2.6.git-paolo/mm/fremap.c | 7 ++++--- linux-2.6.git-paolo/mm/mmap.c | 4 ++++ 2 files changed, 8 insertions(+), 3 deletions(-) diff -puN mm/fremap.c~rfp-private-vma-2 mm/fremap.c --- linux-2.6.git/mm/fremap.c~rfp-private-vma-2 2005-08-24 20:57:13.000000000 +0200 +++ linux-2.6.git-paolo/mm/fremap.c 2005-08-24 20:57:13.000000000 +0200 @@ -221,9 +221,6 @@ retry: if (!vma) goto out_unlock; - if (!(vma->vm_flags & VM_SHARED)) - goto out_unlock; - if (!vma->vm_ops || !vma->vm_ops->populate || end <= start || start < vma->vm_start || end > vma->vm_end) goto out_unlock; @@ -246,6 +243,8 @@ retry: /* Must set VM_NONLINEAR before any pages are populated. */ if (pgoff != linear_page_index(vma, start) && !(vma->vm_flags & VM_NONLINEAR)) { + if (!(vma->vm_flags & VM_SHARED)) + goto out_unlock; if (!has_write_lock) { up_read(&mm->mmap_sem); down_write(&mm->mmap_sem); @@ -264,6 +263,8 @@ retry: if (pgprot_val(pgprot) != pgprot_val(vma->vm_page_prot) && !(vma->vm_flags & VM_NONUNIFORM)) { + if (!(vma->vm_flags & VM_SHARED)) + goto out_unlock; if (!has_write_lock) { up_read(&mm->mmap_sem); down_write(&mm->mmap_sem); diff -puN mm/mmap.c~rfp-private-vma-2 mm/mmap.c --- linux-2.6.git/mm/mmap.c~rfp-private-vma-2 2005-08-24 20:57:13.000000000 +0200 +++ linux-2.6.git-paolo/mm/mmap.c 2005-08-24 20:57:13.000000000 +0200 @@ -1124,6 +1124,10 @@ out: } if (flags & MAP_POPULATE) { up_write(&mm->mmap_sem); + /* + * remap_file_pages() works even if the mapping is private, + * in the linearly-mapped case: + */ sys_remap_file_pages(addr, len, 0, pgoff, flags & MAP_NONBLOCK); down_write(&mm->mmap_sem); _ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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