Merge branch 'sii-m15w' into upstream
[pandora-kernel.git] / arch / sparc64 / kernel / sys_sparc.c
index 5f8c822..054d0ab 100644 (file)
@@ -6,7 +6,6 @@
  * platform.
  */
 
-#include <linux/config.h>
 #include <linux/errno.h>
 #include <linux/types.h>
 #include <linux/sched.h>
 #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 +131,8 @@ 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 +151,12 @@ 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 +168,12 @@ 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 +181,7 @@ 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 +197,121 @@ 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 +355,57 @@ 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 +566,16 @@ 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 +594,9 @@ 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(&current->mm->mmap_sem);
        ret = do_munmap(current->mm, addr, len);
        up_write(&current->mm->mmap_sem);
@@ -384,18 +613,19 @@ 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(&current->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;
 
@@ -471,21 +701,21 @@ extern void check_pending(int signum);
 
 asmlinkage long sys_getdomainname(char __user *name, int len)
 {
-        int nlen;
-       int err = -EFAULT;
+        int nlen, err;
+
+       if (len < 0 || len > __NEW_UTS_LEN)
+               return -EINVAL;
 
        down_read(&uts_sem);
        
        nlen = strlen(system_utsname.domainname) + 1;
-
         if (nlen < len)
                 len = nlen;
-       if (len > __NEW_UTS_LEN)
-               goto done;
-       if (copy_to_user(name, system_utsname.domainname, len))
-               goto done;
-       err = 0;
-done:
+
+       err = -EFAULT;
+       if (!copy_to_user(name, system_utsname.domainname, len))
+               err = 0;
+
        up_read(&uts_sem);
        return err;
 }
@@ -554,12 +784,10 @@ 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) {