From: Rik van Riel <riel@xxxxxxxxxxx> Teach the generic arch_get_unmapped_area(_topdown) code to call the page colouring code. Signed-off-by: Rik van Riel <riel@xxxxxxxxxx> --- arch/mips/include/asm/page.h | 2 - arch/mips/include/asm/pgtable.h | 1 + arch/x86/include/asm/elf.h | 3 - arch/x86/include/asm/pgtable_64.h | 1 + arch/x86/kernel/sys_x86_64.c | 35 +++++++++----- arch/x86/vdso/vma.c | 2 +- include/linux/sched.h | 8 +++- mm/mmap.c | 91 ++++++++++++++++++++++++++++++++----- 8 files changed, 111 insertions(+), 32 deletions(-) diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h index da9bd7d..459cc25 100644 --- a/arch/mips/include/asm/page.h +++ b/arch/mips/include/asm/page.h @@ -63,8 +63,6 @@ extern void build_copy_page(void); extern void clear_page(void * page); extern void copy_page(void * to, void * from); -extern unsigned long shm_align_mask; - static inline unsigned long pages_do_alias(unsigned long addr1, unsigned long addr2) { diff --git a/arch/mips/include/asm/pgtable.h b/arch/mips/include/asm/pgtable.h index b2202a6..f133a4c 100644 --- a/arch/mips/include/asm/pgtable.h +++ b/arch/mips/include/asm/pgtable.h @@ -415,6 +415,7 @@ int phys_mem_access_prot_allowed(struct file *file, unsigned long pfn, */ #define HAVE_ARCH_UNMAPPED_AREA #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN +#define HAVE_ARCH_ALIGN_ADDR /* * No page table caches to initialise diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h index 5939f44..dc2d0bf 100644 --- a/arch/x86/include/asm/elf.h +++ b/arch/x86/include/asm/elf.h @@ -358,8 +358,6 @@ static inline int mmap_is_ia32(void) enum align_flags { ALIGN_VA_32 = BIT(0), ALIGN_VA_64 = BIT(1), - ALIGN_VDSO = BIT(2), - ALIGN_TOPDOWN = BIT(3), }; struct va_alignment { @@ -368,5 +366,4 @@ struct va_alignment { } ____cacheline_aligned; extern struct va_alignment va_align; -extern unsigned long align_addr(unsigned long, struct file *, enum align_flags); #endif /* _ASM_X86_ELF_H */ diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h index 8af36f6..8408ccd 100644 --- a/arch/x86/include/asm/pgtable_64.h +++ b/arch/x86/include/asm/pgtable_64.h @@ -170,6 +170,7 @@ extern void cleanup_highmap(void); #define HAVE_ARCH_UNMAPPED_AREA #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN #define HAVE_ARCH_GET_ADDRESS_RANGE +#define HAVE_ARCH_ALIGN_ADDR #define pgtable_cache_init() do { } while (0) #define check_pgt_cache() do { } while (0) diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c index 2595a5e..ac0afb8 100644 --- a/arch/x86/kernel/sys_x86_64.c +++ b/arch/x86/kernel/sys_x86_64.c @@ -25,31 +25,40 @@ * @flags denotes the allocation direction - bottomup or topdown - * or vDSO; see call sites below. */ -unsigned long align_addr(unsigned long addr, struct file *filp, - enum align_flags flags) +unsigned long arch_align_addr(unsigned long addr, struct file *filp, + unsigned long pgoff, unsigned long flags, + enum mmap_allocation_direction direction) { - unsigned long tmp_addr; + unsigned long tmp_addr = PAGE_ALIGN(addr); /* handle 32- and 64-bit case with a single conditional */ if (va_align.flags < 0 || !(va_align.flags & (2 - mmap_is_ia32()))) - return addr; + return tmp_addr; - if (!(current->flags & PF_RANDOMIZE)) - return addr; + /* Always allow MAP_FIXED. Colouring is a performance thing only. */ + if (flags & MAP_FIXED) + return tmp_addr; - if (!((flags & ALIGN_VDSO) || filp)) - return addr; + if (!(current->flags & PF_RANDOMIZE)) + return tmp_addr; - tmp_addr = addr; + if (!(filp || direction == ALLOC_VDSO)) + return tmp_addr; /* * We need an address which is <= than the original * one only when in topdown direction. */ - if (!(flags & ALIGN_TOPDOWN)) + if (direction == ALLOC_UP) tmp_addr += va_align.mask; tmp_addr &= ~va_align.mask; + tmp_addr += ((pgoff << PAGE_SHIFT) & va_align.mask); + + if (direction == ALLOC_DOWN && tmp_addr > addr) { + tmp_addr -= va_align.mask; + tmp_addr &= ~va_align.mask; + } return tmp_addr; } @@ -159,7 +168,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, full_search: - addr = align_addr(addr, filp, 0); + addr = arch_align_addr(addr, filp, pgoff, flags, ALLOC_UP); for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { /* At this point: (!vma || addr < vma->vm_end). */ @@ -186,7 +195,7 @@ full_search: mm->cached_hole_size = vma->vm_start - addr; addr = vma->vm_end; - addr = align_addr(addr, filp, 0); + addr = arch_align_addr(addr, filp, pgoff, flags, ALLOC_UP); } } @@ -235,7 +244,7 @@ try_again: addr -= len; do { - addr = align_addr(addr, filp, ALIGN_TOPDOWN); + addr = arch_align_addr(addr, filp, pgoff, flags, ALLOC_DOWN); /* * Lookup failure means no vma is above this address, diff --git a/arch/x86/vdso/vma.c b/arch/x86/vdso/vma.c index 00aaf04..83e0355 100644 --- a/arch/x86/vdso/vma.c +++ b/arch/x86/vdso/vma.c @@ -141,7 +141,7 @@ static unsigned long vdso_addr(unsigned long start, unsigned len) * unaligned here as a result of stack start randomization. */ addr = PAGE_ALIGN(addr); - addr = align_addr(addr, NULL, ALIGN_VDSO); + addr = arch_align_addr(addr, NULL, 0, 0, ALLOC_VDSO); return addr; } diff --git a/include/linux/sched.h b/include/linux/sched.h index fc76318..18f9326 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -390,12 +390,18 @@ extern int sysctl_max_map_count; #ifdef CONFIG_MMU enum mmap_allocation_direction { ALLOC_UP, - ALLOC_DOWN + ALLOC_DOWN, + ALLOC_VDSO, }; extern void arch_pick_mmap_layout(struct mm_struct *mm); extern void arch_get_address_range(unsigned long flags, unsigned long *begin, unsigned long *end, enum mmap_allocation_direction direction); +extern unsigned long shm_align_mask; +extern unsigned long +arch_align_addr(unsigned long addr, struct file *filp, + unsigned long pgoff, unsigned long flags, + enum mmap_allocation_direction direction); extern unsigned long arch_get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); diff --git a/mm/mmap.c b/mm/mmap.c index 92cf0bf..0314cb1 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1465,6 +1465,51 @@ unacct_error: return error; } +#ifndef HAVE_ARCH_ALIGN_ADDR +/* Each architecture is responsible for setting this to the required value. */ +unsigned long shm_align_mask = PAGE_SIZE - 1; +EXPORT_SYMBOL(shm_align_mask); + +unsigned long arch_align_addr(unsigned long addr, struct file *filp, + unsigned long pgoff, unsigned long flags, + enum mmap_allocation_direction direction) +{ + unsigned long tmp_addr = PAGE_ALIGN(addr); + + if (shm_align_mask <= PAGE_SIZE) + return tmp_addr; + + /* Allow MAP_FIXED without MAP_SHARED at any address. */ + if ((flags & (MAP_FIXED|MAP_SHARED)) == MAP_FIXED) + return tmp_addr; + + /* Enforce page colouring for any file or MAP_SHARED mapping. */ + if (!(filp || (flags & MAP_SHARED))) + return tmp_addr; + + /* + * We need an address which is <= than the original + * one only when in topdown direction. + */ + if (direction == ALLOC_UP) + tmp_addr += shm_align_mask; + + tmp_addr &= ~shm_align_mask; + tmp_addr += ((pgoff << PAGE_SHIFT) & shm_align_mask); + + /* + * When aligning down, make sure we did not accidentally go up. + * The caller will check for underflow. + */ + if (direction == ALLOC_DOWN && tmp_addr > addr) { + tmp_addr -= shm_align_mask; + tmp_addr &= ~shm_align_mask; + } + + return tmp_addr; +} +#endif + #ifndef HAVE_ARCH_GET_ADDRESS_RANGE void arch_get_address_range(unsigned long flags, unsigned long *begin, unsigned long *end, enum mmap_allocation_direction direction) @@ -1513,18 +1558,22 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, struct mm_struct *mm = current->mm; struct vm_area_struct *vma = NULL; struct rb_node *rb_node; - unsigned long lower_limit, upper_limit; + unsigned long lower_limit, upper_limit, tmp_addr; arch_get_address_range(flags, &lower_limit, &upper_limit, ALLOC_UP); if (len > TASK_SIZE) return -ENOMEM; - if (flags & MAP_FIXED) + if (flags & MAP_FIXED) { + tmp_addr = arch_align_addr(addr, filp, pgoff, flags, ALLOC_UP); + if (tmp_addr != PAGE_ALIGN(addr)) + return -EINVAL; return addr; + } if (addr) { - addr = PAGE_ALIGN(addr); + addr = arch_align_addr(addr, filp, pgoff, flags, ALLOC_UP); vma = find_vma(mm, addr); if (TASK_SIZE - len >= addr && (!vma || addr + len <= vma->vm_start)) @@ -1533,7 +1582,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, /* Find the left-most free area of sufficient size. */ for (addr = 0, rb_node = mm->mm_rb.rb_node; rb_node; ) { - unsigned long vma_start; + unsigned long vma_start, tmp_addr; int found_here = 0; vma = rb_to_vma(rb_node); @@ -1541,13 +1590,17 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, if (vma->vm_start > len) { if (!vma->vm_prev) { /* This is the left-most VMA. */ - if (vma->vm_start - len >= lower_limit) { - addr = lower_limit; + tmp_addr = arch_align_addr(lower_limit, filp, + pgoff, flags, ALLOC_UP); + if (vma->vm_start - len >= tmp_addr) { + addr = tmp_addr; goto found_addr; } } else { /* Is this hole large enough? Remember it. */ vma_start = max(vma->vm_prev->vm_end, lower_limit); + vma_start = arch_align_addr(vma_start, filp, + pgoff, flags, ALLOC_UP); if (vma->vm_start - len >= vma_start) { addr = vma_start; found_here = 1; @@ -1599,6 +1652,8 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, if (addr < lower_limit) addr = lower_limit; + addr = arch_align_addr(addr, filp, pgoff, flags, ALLOC_UP); + found_addr: if (TASK_SIZE - len < addr) return -ENOMEM; @@ -1656,12 +1711,17 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, if (len > TASK_SIZE) return -ENOMEM; - if (flags & MAP_FIXED) + if (flags & MAP_FIXED) { + unsigned long tmp_addr; + tmp_addr = arch_align_addr(addr, filp, pgoff, flags, ALLOC_DOWN); + if (tmp_addr != PAGE_ALIGN(addr)) + return -EINVAL; return addr; + } /* requesting a specific address */ if (addr) { - addr = PAGE_ALIGN(addr); + addr = arch_align_addr(addr, filp, pgoff, flags, ALLOC_DOWN); vma = find_vma(mm, addr); if (TASK_SIZE - len >= addr && (!vma || addr + len <= vma->vm_start)) @@ -1678,7 +1738,9 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, */ if (upper_limit - len > mm->highest_vma) { addr = upper_limit - len; - goto found_addr; + addr = arch_align_addr(addr, filp, pgoff, flags, ALLOC_DOWN); + if (addr > mm->highest_vma); + goto found_addr; } /* Find the right-most free area of sufficient size. */ @@ -1691,9 +1753,14 @@ arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, /* Is this hole large enough? Remember it. */ vma_start = min(vma->vm_start, upper_limit); if (vma_start > len) { - if (!vma->vm_prev || - (vma_start - len >= vma->vm_prev->vm_end)) { - addr = vma_start - len; + unsigned long tmp_addr = vma_start - len; + tmp_addr = arch_align_addr(tmp_addr, filp, + pgoff, flags, ALLOC_DOWN); + /* No underflow? Does it still fit the hole? */ + if (tmp_addr && tmp_addr <= vma_start - len && + (!vma->vm_prev || + tmp_addr >= vma->vm_prev->vm_end)) { + addr = tmp_addr; found_here = 1; } } -- 1.7.7.6 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>