diff options
Diffstat (limited to 'arch/sparc64/kernel/sys_sparc.c')
| -rw-r--r-- | arch/sparc64/kernel/sys_sparc.c | 297 |
1 files changed, 263 insertions, 34 deletions
diff --git a/arch/sparc64/kernel/sys_sparc.c b/arch/sparc64/kernel/sys_sparc.c index 5f8c822a2b4a..7a869138c37f 100644 --- a/arch/sparc64/kernel/sys_sparc.c +++ b/arch/sparc64/kernel/sys_sparc.c @@ -25,25 +25,93 @@ #include <linux/syscalls.h> #include <linux/ipc.h> #include <linux/personality.h> +#include <linux/random.h> #include <asm/uaccess.h> #include <asm/ipc.h> #include <asm/utrap.h> #include <asm/perfctr.h> +#include <asm/a.out.h> /* #define DEBUG_UNIMP_SYSCALL */ -/* XXX Make this per-binary type, this way we can detect the type of - * XXX a binary. Every Sparc executable calls this very early on. - */ asmlinkage unsigned long sys_getpagesize(void) { return PAGE_SIZE; } -#define COLOUR_ALIGN(addr,pgoff) \ - ((((addr)+SHMLBA-1)&~(SHMLBA-1)) + \ - (((pgoff)<<PAGE_SHIFT) & (SHMLBA-1))) +#define VA_EXCLUDE_START (0x0000080000000000UL - (1UL << 32UL)) +#define VA_EXCLUDE_END (0xfffff80000000000UL + (1UL << 32UL)) + +/* Does addr --> addr+len fall within 4GB of the VA-space hole or + * overflow past the end of the 64-bit address space? + */ +static inline int invalid_64bit_range(unsigned long addr, unsigned long len) +{ + unsigned long va_exclude_start, va_exclude_end; + + va_exclude_start = VA_EXCLUDE_START; + va_exclude_end = VA_EXCLUDE_END; + + if (unlikely(len >= va_exclude_start)) + return 1; + + if (unlikely((addr + len) < addr)) + return 1; + + if (unlikely((addr >= va_exclude_start && addr < va_exclude_end) || + ((addr + len) >= va_exclude_start && + (addr + len) < va_exclude_end))) + return 1; + + return 0; +} + +/* Does start,end straddle the VA-space hole? */ +static inline int straddles_64bit_va_hole(unsigned long start, unsigned long end) +{ + unsigned long va_exclude_start, va_exclude_end; + + va_exclude_start = VA_EXCLUDE_START; + va_exclude_end = VA_EXCLUDE_END; + + if (likely(start < va_exclude_start && end < va_exclude_start)) + return 0; + + if (likely(start >= va_exclude_end && end >= va_exclude_end)) + return 0; + + return 1; +} + +/* These functions differ from the default implementations in + * mm/mmap.c in two ways: + * + * 1) For file backed MAP_SHARED mmap()'s we D-cache color align, + * for fixed such mappings we just validate what the user gave us. + * 2) For 64-bit tasks we avoid mapping anything within 4GB of + * the spitfire/niagara VA-hole. + */ + +static inline unsigned long COLOUR_ALIGN(unsigned long addr, + unsigned long pgoff) +{ + unsigned long base = (addr+SHMLBA-1)&~(SHMLBA-1); + unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1); + + return base + off; +} + +static inline unsigned long COLOUR_ALIGN_DOWN(unsigned long addr, + unsigned long pgoff) +{ + unsigned long base = addr & ~(SHMLBA-1); + unsigned long off = (pgoff<<PAGE_SHIFT) & (SHMLBA-1); + + if (base + off <= addr) + return base + off; + return base - off; +} unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags) { @@ -64,8 +132,8 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi } if (test_thread_flag(TIF_32BIT)) - task_size = 0xf0000000UL; - if (len > task_size || len > -PAGE_OFFSET) + task_size = STACK_TOP32; + if (unlikely(len > task_size || len >= VA_EXCLUDE_START)) return -ENOMEM; do_color_align = 0; @@ -84,11 +152,12 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi return addr; } - if (len <= mm->cached_hole_size) { + if (len > mm->cached_hole_size) { + start_addr = addr = mm->free_area_cache; + } else { + start_addr = addr = TASK_UNMAPPED_BASE; mm->cached_hole_size = 0; - mm->free_area_cache = TASK_UNMAPPED_BASE; } - start_addr = addr = mm->free_area_cache; task_size -= len; @@ -100,11 +169,12 @@ full_search: for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { /* At this point: (!vma || addr < vma->vm_end). */ - if (addr < PAGE_OFFSET && -PAGE_OFFSET - len < addr) { - addr = PAGE_OFFSET; - vma = find_vma(mm, PAGE_OFFSET); + if (addr < VA_EXCLUDE_START && + (addr + len) >= VA_EXCLUDE_START) { + addr = VA_EXCLUDE_END; + vma = find_vma(mm, VA_EXCLUDE_END); } - if (task_size < addr) { + if (unlikely(task_size < addr)) { if (start_addr != TASK_UNMAPPED_BASE) { start_addr = addr = TASK_UNMAPPED_BASE; mm->cached_hole_size = 0; @@ -112,7 +182,7 @@ full_search: } return -ENOMEM; } - if (!vma || addr + len <= vma->vm_start) { + if (likely(!vma || addr + len <= vma->vm_start)) { /* * Remember the place where we stopped the search: */ @@ -128,6 +198,121 @@ full_search: } } +unsigned long +arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, + const unsigned long len, const unsigned long pgoff, + const unsigned long flags) +{ + struct vm_area_struct *vma; + struct mm_struct *mm = current->mm; + unsigned long task_size = STACK_TOP32; + unsigned long addr = addr0; + int do_color_align; + + /* This should only ever run for 32-bit processes. */ + BUG_ON(!test_thread_flag(TIF_32BIT)); + + if (flags & MAP_FIXED) { + /* We do not accept a shared mapping if it would violate + * cache aliasing constraints. + */ + if ((flags & MAP_SHARED) && + ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))) + return -EINVAL; + return addr; + } + + if (unlikely(len > task_size)) + return -ENOMEM; + + do_color_align = 0; + if (filp || (flags & MAP_SHARED)) + do_color_align = 1; + + /* requesting a specific address */ + if (addr) { + if (do_color_align) + addr = COLOUR_ALIGN(addr, pgoff); + else + addr = PAGE_ALIGN(addr); + + vma = find_vma(mm, addr); + if (task_size - len >= addr && + (!vma || addr + len <= vma->vm_start)) + return addr; + } + + /* check if free_area_cache is useful for us */ + if (len <= mm->cached_hole_size) { + mm->cached_hole_size = 0; + mm->free_area_cache = mm->mmap_base; + } + + /* either no address requested or can't fit in requested address hole */ + addr = mm->free_area_cache; + if (do_color_align) { + unsigned long base = COLOUR_ALIGN_DOWN(addr-len, pgoff); + + addr = base + len; + } + + /* make sure it can fit in the remaining address space */ + if (likely(addr > len)) { + vma = find_vma(mm, addr-len); + if (!vma || addr <= vma->vm_start) { + /* remember the address as a hint for next time */ + return (mm->free_area_cache = addr-len); + } + } + + if (unlikely(mm->mmap_base < len)) + goto bottomup; + + addr = mm->mmap_base-len; + if (do_color_align) + addr = COLOUR_ALIGN_DOWN(addr, pgoff); + + do { + /* + * Lookup failure means no vma is above this address, + * else if new region fits below vma->vm_start, + * return with success: + */ + vma = find_vma(mm, addr); + if (likely(!vma || addr+len <= vma->vm_start)) { + /* remember the address as a hint for next time */ + return (mm->free_area_cache = addr); + } + + /* remember the largest hole we saw so far */ + if (addr + mm->cached_hole_size < vma->vm_start) + mm->cached_hole_size = vma->vm_start - addr; + + /* try just below the current vma->vm_start */ + addr = vma->vm_start-len; + if (do_color_align) + addr = COLOUR_ALIGN_DOWN(addr, pgoff); + } while (likely(len < vma->vm_start)); + +bottomup: + /* + * A failed mmap() very likely causes application failure, + * so fall back to the bottom-up function here. This scenario + * can happen with large stack limits and large mmap() + * allocations. + */ + mm->cached_hole_size = ~0UL; + mm->free_area_cache = TASK_UNMAPPED_BASE; + addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags); + /* + * Restore the topdown base: + */ + mm->free_area_cache = mm->mmap_base; + mm->cached_hole_size = ~0UL; + + return addr; +} + /* Try to align mapping such that we align it as much as possible. */ unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags) { @@ -171,15 +356,57 @@ unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, u return addr; } +/* Essentially the same as PowerPC... */ +void arch_pick_mmap_layout(struct mm_struct *mm) +{ + unsigned long random_factor = 0UL; + + if (current->flags & PF_RANDOMIZE) { + random_factor = get_random_int(); + if (test_thread_flag(TIF_32BIT)) + random_factor &= ((1 * 1024 * 1024) - 1); + else + random_factor = ((random_factor << PAGE_SHIFT) & + 0xffffffffUL); + } + + /* + * Fall back to the standard layout if the personality + * bit is set, or if the expected stack growth is unlimited: + */ + if (!test_thread_flag(TIF_32BIT) || + (current->personality & ADDR_COMPAT_LAYOUT) || + current->signal->rlim[RLIMIT_STACK].rlim_cur == RLIM_INFINITY || + sysctl_legacy_va_layout) { + mm->mmap_base = TASK_UNMAPPED_BASE + random_factor; + mm->get_unmapped_area = arch_get_unmapped_area; + mm->unmap_area = arch_unmap_area; + } else { + /* We know it's 32-bit */ + unsigned long task_size = STACK_TOP32; + unsigned long gap; + + gap = current->signal->rlim[RLIMIT_STACK].rlim_cur; + if (gap < 128 * 1024 * 1024) + gap = 128 * 1024 * 1024; + if (gap > (task_size / 6 * 5)) + gap = (task_size / 6 * 5); + + mm->mmap_base = PAGE_ALIGN(task_size - gap - random_factor); + mm->get_unmapped_area = arch_get_unmapped_area_topdown; + mm->unmap_area = arch_unmap_area_topdown; + } +} + asmlinkage unsigned long sparc_brk(unsigned long brk) { /* People could try to be nasty and use ta 0x6d in 32bit programs */ - if (test_thread_flag(TIF_32BIT) && - brk >= 0xf0000000UL) + if (test_thread_flag(TIF_32BIT) && brk >= STACK_TOP32) return current->mm->brk; - if ((current->mm->brk & PAGE_OFFSET) != (brk & PAGE_OFFSET)) + if (unlikely(straddles_64bit_va_hole(current->mm->brk, brk))) return current->mm->brk; + return sys_brk(brk); } @@ -340,13 +567,16 @@ asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len, retval = -EINVAL; if (test_thread_flag(TIF_32BIT)) { - if (len > 0xf0000000UL || - ((flags & MAP_FIXED) && addr > 0xf0000000UL - len)) + if (len >= STACK_TOP32) + goto out_putf; + + if ((flags & MAP_FIXED) && addr > STACK_TOP32 - len) goto out_putf; } else { - if (len > -PAGE_OFFSET || - ((flags & MAP_FIXED) && - addr < PAGE_OFFSET && addr + len > -PAGE_OFFSET)) + if (len >= VA_EXCLUDE_START) + goto out_putf; + + if ((flags & MAP_FIXED) && invalid_64bit_range(addr, len)) goto out_putf; } @@ -365,9 +595,9 @@ asmlinkage long sys64_munmap(unsigned long addr, size_t len) { long ret; - if (len > -PAGE_OFFSET || - (addr < PAGE_OFFSET && addr + len > -PAGE_OFFSET)) + if (invalid_64bit_range(addr, len)) return -EINVAL; + down_write(¤t->mm->mmap_sem); ret = do_munmap(current->mm, addr, len); up_write(¤t->mm->mmap_sem); @@ -384,18 +614,19 @@ asmlinkage unsigned long sys64_mremap(unsigned long addr, { struct vm_area_struct *vma; unsigned long ret = -EINVAL; + if (test_thread_flag(TIF_32BIT)) goto out; - if (old_len > -PAGE_OFFSET || new_len > -PAGE_OFFSET) + if (unlikely(new_len >= VA_EXCLUDE_START)) goto out; - if (addr < PAGE_OFFSET && addr + old_len > -PAGE_OFFSET) + if (unlikely(invalid_64bit_range(addr, old_len))) goto out; + down_write(¤t->mm->mmap_sem); if (flags & MREMAP_FIXED) { - if (new_addr < PAGE_OFFSET && - new_addr + new_len > -PAGE_OFFSET) + if (invalid_64bit_range(new_addr, new_len)) goto out_sem; - } else if (addr < PAGE_OFFSET && addr + new_len > -PAGE_OFFSET) { + } else if (invalid_64bit_range(addr, new_len)) { unsigned long map_flags = 0; struct file *file = NULL; @@ -554,12 +785,10 @@ asmlinkage long sys_utrap_install(utrap_entry_t type, } if (!current_thread_info()->utraps) { current_thread_info()->utraps = - kmalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long), GFP_KERNEL); + kzalloc((UT_TRAP_INSTRUCTION_31+1)*sizeof(long), GFP_KERNEL); if (!current_thread_info()->utraps) return -ENOMEM; current_thread_info()->utraps[0] = 1; - memset(current_thread_info()->utraps+1, 0, - UT_TRAP_INSTRUCTION_31*sizeof(long)); } else { if ((utrap_handler_t)current_thread_info()->utraps[type] != new_p && current_thread_info()->utraps[0] > 1) { |