[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / x86 / kernel / sys_x86_64.c

#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/syscalls.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/smp.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/stat.h>
#include <linux/mman.h>
#include <linux/file.h>
#include <linux/utsname.h>
#include <linux/personality.h>
#include <linux/random.h>
#include <linux/uaccess.h>
#include <linux/elf.h>

#include <asm/ia32.h>
#include <asm/syscalls.h>

/*
 * Align a virtual address to avoid aliasing in the I$ on AMD F15h.
 *
 * @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 tmp_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;

	if (!(current->flags & PF_RANDOMIZE))
		return addr;

	if (!((flags & ALIGN_VDSO) || filp))
		return addr;

	tmp_addr = addr;

	/*
	 * We need an address which is <= than the original
	 * one only when in topdown direction.
	 */
	if (!(flags & ALIGN_TOPDOWN))
		tmp_addr += va_align.mask;

	tmp_addr &= ~va_align.mask;

	return tmp_addr;
}

static int __init control_va_addr_alignment(char *str)
{
	/* guard against enabling this on other CPU families */
	if (va_align.flags < 0)
		return 1;

	if (*str == 0)
		return 1;

	if (*str == '=')
		str++;

	if (!strcmp(str, "32"))
		va_align.flags = ALIGN_VA_32;
	else if (!strcmp(str, "64"))
		va_align.flags = ALIGN_VA_64;
	else if (!strcmp(str, "off"))
		va_align.flags = 0;
	else if (!strcmp(str, "on"))
		va_align.flags = ALIGN_VA_32 | ALIGN_VA_64;
	else
		return 0;

	return 1;
}
__setup("align_va_addr", control_va_addr_alignment);

SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
		unsigned long, prot, unsigned long, flags,
		unsigned long, fd, unsigned long, off)
{
	long error;
	error = -EINVAL;
	if (off & ~PAGE_MASK)
		goto out;

	error = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
out:
	return error;
}

static void find_start_end(unsigned long flags, unsigned long *begin,
			   unsigned long *end)
{
	if (!test_thread_flag(TIF_IA32) && (flags & MAP_32BIT)) {
		unsigned long new_begin;
		/* This is usually used needed to map code in small
		   model, so it needs to be in the first 31bit. Limit
		   it to that.  This means we need to move the
		   unmapped base down for this case. This can give
		   conflicts with the heap, but we assume that glibc
		   malloc knows how to fall back to mmap. Give it 1GB
		   of playground for now. -AK */
		*begin = 0x40000000;
		*end = 0x80000000;
		if (current->flags & PF_RANDOMIZE) {
			new_begin = randomize_range(*begin, *begin + 0x02000000, 0);
			if (new_begin)
				*begin = new_begin;
		}
	} else {
		*begin = TASK_UNMAPPED_BASE;
		*end = TASK_SIZE;
	}
}

unsigned long
arch_get_unmapped_area(struct file *filp, unsigned long addr,
		unsigned long len, unsigned long pgoff, unsigned long flags)
{
	struct mm_struct *mm = current->mm;
	struct vm_area_struct *vma;
	unsigned long start_addr;
	unsigned long begin, end;

	if (flags & MAP_FIXED)
		return addr;

	find_start_end(flags, &begin, &end);

	if (len > end)
		return -ENOMEM;

	if (addr) {
		addr = PAGE_ALIGN(addr);
		vma = find_vma(mm, addr);
		if (end - len >= addr &&
		    (!vma || addr + len <= vma->vm_start))
			return addr;
	}
	if (((flags & MAP_32BIT) || test_thread_flag(TIF_IA32))
	    && len <= mm->cached_hole_size) {
		mm->cached_hole_size = 0;
		mm->free_area_cache = begin;
	}
	addr = mm->free_area_cache;
	if (addr < begin)
		addr = begin;
	start_addr = addr;

full_search:

	addr = align_addr(addr, filp, 0);

	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
		/* At this point:  (!vma || addr < vma->vm_end). */
		if (end - len < addr) {
			/*
			 * Start a new search - just in case we missed
			 * some holes.
			 */
			if (start_addr != begin) {
				start_addr = addr = begin;
				mm->cached_hole_size = 0;
				goto full_search;
			}
			return -ENOMEM;
		}
		if (!vma || addr + len <= vma->vm_start) {
			/*
			 * Remember the place where we stopped the search:
			 */
			mm->free_area_cache = addr + len;
			return addr;
		}
		if (addr + mm->cached_hole_size < vma->vm_start)
			mm->cached_hole_size = vma->vm_start - addr;

		addr = vma->vm_end;
		addr = align_addr(addr, filp, 0);
	}
}


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 addr = addr0;

	/* requested length too big for entire address space */
	if (len > TASK_SIZE)
		return -ENOMEM;

	if (flags & MAP_FIXED)
		return addr;

	/* for MAP_32BIT mappings we force the legact mmap base */
	if (!test_thread_flag(TIF_IA32) && (flags & MAP_32BIT))
		goto bottomup;

	/* requesting a specific address */
	if (addr) {
		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;

	/* make sure it can fit in the remaining address space */
	if (addr > len) {
		unsigned long tmp_addr = align_addr(addr - len, filp,
						    ALIGN_TOPDOWN);

		vma = find_vma(mm, tmp_addr);
		if (!vma || tmp_addr + len <= vma->vm_start)
			/* remember the address as a hint for next time */
			return mm->free_area_cache = tmp_addr;
	}

	if (mm->mmap_base < len)
		goto bottomup;

	addr = mm->mmap_base-len;

	do {
		addr = align_addr(addr, filp, ALIGN_TOPDOWN);

		/*
		 * 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 (!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;
	} while (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;
}
Commit	Line	Data
1da177e4 LT	1	#include <linux/errno.h>
	2	#include <linux/sched.h>
	3	#include <linux/syscalls.h>
	4	#include <linux/mm.h>
4e950f6f	5	#include <linux/fs.h>
1da177e4	6	#include <linux/smp.h>
1da177e4 LT	7	#include <linux/sem.h>
	8	#include <linux/msg.h>
	9	#include <linux/shm.h>
	10	#include <linux/stat.h>
	11	#include <linux/mman.h>
	12	#include <linux/file.h>
	13	#include <linux/utsname.h>
	14	#include <linux/personality.h>
cc503c1b	15	#include <linux/random.h>
e9c8abb6	16	#include <linux/uaccess.h>
910b2c51	17	#include <linux/elf.h>
1da177e4	18
1da177e4	19	#include <asm/ia32.h>
bbc1f698	20	#include <asm/syscalls.h>
1da177e4	21
dfb09f9b BP	22	/*
	23	* Align a virtual address to avoid aliasing in the I$ on AMD F15h.
	24	*
	25	* @flags denotes the allocation direction - bottomup or topdown -
	26	* or vDSO; see call sites below.
	27	*/
	28	unsigned long align_addr(unsigned long addr, struct file *filp,
	29	enum align_flags flags)
	30	{
	31	unsigned long tmp_addr;
	32
	33	/* handle 32- and 64-bit case with a single conditional */
	34	if (va_align.flags < 0 \|\| !(va_align.flags & (2 - mmap_is_ia32())))
	35	return addr;
	36
	37	if (!(current->flags & PF_RANDOMIZE))
	38	return addr;
	39
	40	if (!((flags & ALIGN_VDSO) \|\| filp))
	41	return addr;
	42
	43	tmp_addr = addr;
	44
	45	/*
	46	* We need an address which is <= than the original
	47	* one only when in topdown direction.
	48	*/
	49	if (!(flags & ALIGN_TOPDOWN))
	50	tmp_addr += va_align.mask;
	51
	52	tmp_addr &= ~va_align.mask;
	53
	54	return tmp_addr;
	55	}
	56
	57	static int __init control_va_addr_alignment(char *str)
	58	{
	59	/* guard against enabling this on other CPU families */
	60	if (va_align.flags < 0)
	61	return 1;
	62
	63	if (*str == 0)
	64	return 1;
	65
	66	if (*str == '=')
	67	str++;
	68
	69	if (!strcmp(str, "32"))
	70	va_align.flags = ALIGN_VA_32;
	71	else if (!strcmp(str, "64"))
	72	va_align.flags = ALIGN_VA_64;
	73	else if (!strcmp(str, "off"))
	74	va_align.flags = 0;
	75	else if (!strcmp(str, "on"))
	76	va_align.flags = ALIGN_VA_32 \| ALIGN_VA_64;
	77	else
	78	return 0;
	79
	80	return 1;
	81	}
	82	__setup("align_va_addr", control_va_addr_alignment);
	83
0ac676fb JB	84	SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
	85	unsigned long, prot, unsigned long, flags,
	86	unsigned long, fd, unsigned long, off)
1da177e4 LT	87	{
1da177e4 LT	88	long error;
1da177e4 LT	89	error = -EINVAL;
	90	if (off & ~PAGE_MASK)
	91	goto out;
	92
f8b72560	93	error = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
1da177e4 LT	94	out:
	95	return error;
	96	}
	97
	98	static void find_start_end(unsigned long flags, unsigned long *begin,
	99	unsigned long *end)
	100	{
84929801	101	if (!test_thread_flag(TIF_IA32) && (flags & MAP_32BIT)) {
cc503c1b	102	unsigned long new_begin;
1da177e4 LT	103	/* This is usually used needed to map code in small
	104	model, so it needs to be in the first 31bit. Limit
	105	it to that. This means we need to move the
	106	unmapped base down for this case. This can give
	107	conflicts with the heap, but we assume that glibc
	108	malloc knows how to fall back to mmap. Give it 1GB
e9c8abb6 GP	109	of playground for now. -AK */
	110	*begin = 0x40000000;
	111	*end = 0x80000000;
cc503c1b JK	112	if (current->flags & PF_RANDOMIZE) {
	113	new_begin = randomize_range(begin, begin + 0x02000000, 0);
	114	if (new_begin)
	115	*begin = new_begin;
	116	}
84929801 SS	117	} else {
84929801 SS	118	*begin = TASK_UNMAPPED_BASE;
e9c8abb6	119	*end = TASK_SIZE;
84929801	120	}
e9c8abb6	121	}
1da177e4 LT	122
	123	unsigned long
	124	arch_get_unmapped_area(struct file *filp, unsigned long addr,
	125	unsigned long len, unsigned long pgoff, unsigned long flags)
	126	{
	127	struct mm_struct *mm = current->mm;
	128	struct vm_area_struct *vma;
	129	unsigned long start_addr;
	130	unsigned long begin, end;
e9c8abb6	131
11300a64 BH	132	if (flags & MAP_FIXED)
	133	return addr;
	134
e9c8abb6	135	find_start_end(flags, &begin, &end);
1da177e4 LT	136
	137	if (len > end)
	138	return -ENOMEM;
	139
	140	if (addr) {
	141	addr = PAGE_ALIGN(addr);
	142	vma = find_vma(mm, addr);
	143	if (end - len >= addr &&
	144	(!vma \|\| addr + len <= vma->vm_start))
	145	return addr;
	146	}
1363c3cd WW	147	if (((flags & MAP_32BIT) \|\| test_thread_flag(TIF_IA32))
1363c3cd WW	148	&& len <= mm->cached_hole_size) {
e9c8abb6	149	mm->cached_hole_size = 0;
1363c3cd WW	150	mm->free_area_cache = begin;
1363c3cd WW	151	}
1da177e4	152	addr = mm->free_area_cache;
e9c8abb6 GP	153	if (addr < begin)
e9c8abb6 GP	154	addr = begin;
1da177e4 LT	155	start_addr = addr;
	156
	157	full_search:
dfb09f9b BP	158
	159	addr = align_addr(addr, filp, 0);
	160
1da177e4 LT	161	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
	162	/* At this point: (!vma \|\| addr < vma->vm_end). */
	163	if (end - len < addr) {
	164	/*
	165	* Start a new search - just in case we missed
	166	* some holes.
	167	*/
	168	if (start_addr != begin) {
	169	start_addr = addr = begin;
1363c3cd	170	mm->cached_hole_size = 0;
1da177e4 LT	171	goto full_search;
	172	}
	173	return -ENOMEM;
	174	}
	175	if (!vma \|\| addr + len <= vma->vm_start) {
	176	/*
	177	* Remember the place where we stopped the search:
	178	*/
	179	mm->free_area_cache = addr + len;
	180	return addr;
	181	}
1363c3cd	182	if (addr + mm->cached_hole_size < vma->vm_start)
e9c8abb6	183	mm->cached_hole_size = vma->vm_start - addr;
1363c3cd	184
1da177e4	185	addr = vma->vm_end;
dfb09f9b	186	addr = align_addr(addr, filp, 0);
1da177e4 LT	187	}
	188	}
	189
cc503c1b JK	190
	191	unsigned long
	192	arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0,
	193	const unsigned long len, const unsigned long pgoff,
	194	const unsigned long flags)
	195	{
	196	struct vm_area_struct *vma;
	197	struct mm_struct *mm = current->mm;
	198	unsigned long addr = addr0;
	199
	200	/* requested length too big for entire address space */
	201	if (len > TASK_SIZE)
	202	return -ENOMEM;
	203
	204	if (flags & MAP_FIXED)
	205	return addr;
	206
	207	/* for MAP_32BIT mappings we force the legact mmap base */
	208	if (!test_thread_flag(TIF_IA32) && (flags & MAP_32BIT))
	209	goto bottomup;
	210
	211	/* requesting a specific address */
	212	if (addr) {
	213	addr = PAGE_ALIGN(addr);
	214	vma = find_vma(mm, addr);
	215	if (TASK_SIZE - len >= addr &&
	216	(!vma \|\| addr + len <= vma->vm_start))
	217	return addr;
	218	}
	219
	220	/* check if free_area_cache is useful for us */
	221	if (len <= mm->cached_hole_size) {
bb1ad820 AM	222	mm->cached_hole_size = 0;
	223	mm->free_area_cache = mm->mmap_base;
	224	}
cc503c1b JK	225
	226	/* either no address requested or can't fit in requested address hole */
	227	addr = mm->free_area_cache;
	228
	229	/* make sure it can fit in the remaining address space */
	230	if (addr > len) {
dfb09f9b BP	231	unsigned long tmp_addr = align_addr(addr - len, filp,
	232	ALIGN_TOPDOWN);
	233
	234	vma = find_vma(mm, tmp_addr);
	235	if (!vma \|\| tmp_addr + len <= vma->vm_start)
cc503c1b	236	/* remember the address as a hint for next time */
dfb09f9b	237	return mm->free_area_cache = tmp_addr;
cc503c1b JK	238	}
	239
	240	if (mm->mmap_base < len)
	241	goto bottomup;
	242
	243	addr = mm->mmap_base-len;
	244
	245	do {
dfb09f9b BP	246	addr = align_addr(addr, filp, ALIGN_TOPDOWN);
dfb09f9b BP	247
cc503c1b JK	248	/*
	249	* Lookup failure means no vma is above this address,
	250	* else if new region fits below vma->vm_start,
	251	* return with success:
	252	*/
	253	vma = find_vma(mm, addr);
	254	if (!vma \|\| addr+len <= vma->vm_start)
	255	/* remember the address as a hint for next time */
e9c8abb6	256	return mm->free_area_cache = addr;
cc503c1b	257
bb1ad820 AM	258	/* remember the largest hole we saw so far */
	259	if (addr + mm->cached_hole_size < vma->vm_start)
	260	mm->cached_hole_size = vma->vm_start - addr;
cc503c1b JK	261
	262	/* try just below the current vma->vm_start */
	263	addr = vma->vm_start-len;
	264	} while (len < vma->vm_start);
	265
	266	bottomup:
	267	/*
	268	* A failed mmap() very likely causes application failure,
	269	* so fall back to the bottom-up function here. This scenario
	270	* can happen with large stack limits and large mmap()
	271	* allocations.
	272	*/
	273	mm->cached_hole_size = ~0UL;
bb1ad820	274	mm->free_area_cache = TASK_UNMAPPED_BASE;
cc503c1b JK	275	addr = arch_get_unmapped_area(filp, addr0, len, pgoff, flags);
	276	/*
	277	* Restore the topdown base:
	278	*/
	279	mm->free_area_cache = mm->mmap_base;
	280	mm->cached_hole_size = ~0UL;
	281
	282	return addr;
	283	}