BACKPORT: maccess: rename probe_kernel_address to get_kernel_nofault

Better describe what this helper does, and match the naming of
copy_from_kernel_nofault.

Also switch the argument order around, so that it acts and looks
like get_user().

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change-Id: Ia3e47b1cbf80a23b85dc408b3d90db770a27a3dd

arch/arm/kernel/traps.c

@@ -391,7 +391,7 @@ int is_valid_bugaddr(unsigned long pc)
 	u32 insn = __opcode_to_mem_arm(BUG_INSTR_VALUE);
 #endif
 
-	if (probe_kernel_address((unsigned *)pc, bkpt))
+	if (get_kernel_nofault(bkpt, (unsigned *)pc))
 		return 0;
 
 	return bkpt == insn;

arch/arm/mm/alignment.c

@@ -774,7 +774,7 @@ static int alignment_get_arm(struct pt_regs *regs, u32 *ip, u32 *inst)
 	if (user_mode(regs))
 		fault = get_user(instr, ip);
 	else
-		fault = probe_kernel_address(ip, instr);
+		fault = get_kernel_nofault(instr, ip);
 
 	*inst = __mem_to_opcode_arm(instr);
 
@@ -789,7 +789,7 @@ static int alignment_get_thumb(struct pt_regs *regs, u16 *ip, u16 *inst)
 	if (user_mode(regs))
 		fault = get_user(instr, ip);
 	else
-		fault = probe_kernel_address(ip, instr);
+		fault = get_kernel_nofault(instr, ip);
 
 	*inst = __mem_to_opcode_thumb16(instr);
 

arch/arm64/kernel/traps.c

@@ -311,7 +311,7 @@ static int call_undef_hook(struct pt_regs *regs)
 
 	if (!user_mode(regs)) {
 		__le32 instr_le;
-		if (probe_kernel_address((__force __le32 *)pc, instr_le))
+		if (get_kernel_nofault(instr_le, (__force __le32 *)pc))
 			goto exit;
 		instr = le32_to_cpu(instr_le);
 	} else if (compat_thumb_mode(regs)) {

arch/ia64/include/asm/sections.h

@@ -35,7 +35,7 @@ static inline void *dereference_function_descriptor(void *ptr)
 	struct fdesc *desc = ptr;
 	void *p;
 
-	if (!probe_kernel_address(&desc->ip, p))
+	if (!get_kernel_nofault(p, &desc->ip))
 		ptr = p;
 	return ptr;
 }

arch/parisc/kernel/process.c

@@ -298,7 +298,7 @@ void *dereference_function_descriptor(void *ptr)
 	Elf64_Fdesc *desc = ptr;
 	void *p;
 
-	if (!probe_kernel_address(&desc->addr, p))
+	if (!get_kernel_nofault(p, &desc->addr))
 		ptr = p;
 	return ptr;
 }

arch/powerpc/include/asm/sections.h

@@ -85,7 +85,7 @@ static inline void *dereference_function_descriptor(void *ptr)
 	struct ppc64_opd_entry *desc = ptr;
 	void *p;
 
-	if (!probe_kernel_address(&desc->funcaddr, p))
+	if (!get_kernel_nofault(p, &desc->funcaddr))
 		ptr = p;
 	return ptr;
 }

arch/powerpc/kernel/kgdb.c

@@ -420,7 +420,7 @@ int kgdb_arch_set_breakpoint(struct kgdb_bkpt *bpt)
 	unsigned int instr;
 	unsigned int *addr = (unsigned int *)bpt->bpt_addr;
 
-	err = probe_kernel_address(addr, instr);
+	err = get_kernel_nofault(instr, addr);
 	if (err)
 		return err;
 

arch/powerpc/kernel/process.c

@@ -1239,7 +1239,7 @@ static void show_instructions(struct pt_regs *regs)
 			pr_cont("\n");
 
 		if (!__kernel_text_address(pc) ||
-		    probe_kernel_address((const void *)pc, instr)) {
+		    get_kernel_nofault(instr, (const void *)pc)) {
 			pr_cont("XXXXXXXX ");
 		} else {
 			if (nip == pc)
@@ -1283,7 +1283,7 @@ void show_user_instructions(struct pt_regs *regs)
 		for (i = 0; i < 8 && n; i++, n--, pc += sizeof(int)) {
 			int instr;
 
-			if (probe_kernel_address((const void *)pc, instr)) {
+			if (get_kernel_nofault(instr, const void *)pc)) {
 				seq_buf_printf(&s, "XXXXXXXX ");
 				continue;
 			}

arch/powerpc/sysdev/fsl_pci.c

@@ -1078,7 +1078,7 @@ int fsl_pci_mcheck_exception(struct pt_regs *regs)
 			ret = get_user(inst, (__u32 __user *)regs->nip);
 			pagefault_enable();
 		} else {
-			ret = probe_kernel_address((void *)regs->nip, inst);
+			ret = get_kernel_nofault(inst, (void *)regs->nip);
 		}
 
 		if (!ret && mcheck_handle_load(regs, inst)) {

arch/riscv/kernel/traps.c

@@ -120,7 +120,7 @@ static inline unsigned long get_break_insn_length(unsigned long pc)
 {
 	bug_insn_t insn;
 
-	if (probe_kernel_address((bug_insn_t *)pc, insn))
+	if (get_kernel_nofault(insn, (bug_insn_t *)pc))
 		return 0;
 	return (((insn & __INSN_LENGTH_MASK) == __INSN_LENGTH_32) ? 4UL : 2UL);
 }
@@ -142,7 +142,7 @@ int is_valid_bugaddr(unsigned long pc)
 
 	if (pc < VMALLOC_START)
 		return 0;
-	if (probe_kernel_address((bug_insn_t *)pc, insn))
+	if (get_kernel_nofault(insn, (bug_insn_t *)pc))
 		return 0;
 	if ((insn & __INSN_LENGTH_MASK) == __INSN_LENGTH_32)
 		return (insn == __BUG_INSN_32);

arch/s390/mm/fault.c

@@ -105,7 +105,7 @@ static int bad_address(void *p)
 {
 	unsigned long dummy;
 
-	return probe_kernel_address((unsigned long *)p, dummy);
+	return get_kernel_nofault(dummy, (unsigned long *)p);
 }
 
 static void dump_pagetable(unsigned long asce, unsigned long address)

arch/sh/kernel/traps.c

@@ -118,7 +118,7 @@ int is_valid_bugaddr(unsigned long addr)
 
 	if (addr < PAGE_OFFSET)
 		return 0;
-	if (probe_kernel_address((insn_size_t *)addr, opcode))
+	if (get_kernel_nofault(opcode, (insn_size_t *)addr))
 		return 0;
 	if (opcode == TRAPA_BUG_OPCODE)
 		return 1;

arch/x86/kernel/probe_roms.c

@@ -99,7 +99,7 @@ static bool probe_list(struct pci_dev *pdev, unsigned short vendor,
 	unsigned short device;
 
 	do {
-		if (probe_kernel_address(rom_list, device) != 0)
+		if (get_kernel_nofault(device, rom_list) != 0)
 			device = 0;
 
 		if (device && match_id(pdev, vendor, device))
@@ -125,13 +125,13 @@ static struct resource *find_oprom(struct pci_dev *pdev)
 			break;
 
 		rom = isa_bus_to_virt(res->start);
-		if (probe_kernel_address(rom + 0x18, offset) != 0)
+		if (get_kernel_nofault(offset, rom + 0x18) != 0)
 			continue;
 
-		if (probe_kernel_address(rom + offset + 0x4, vendor) != 0)
+		if (get_kernel_nofault(vendor, rom + offset + 0x4) != 0)
 			continue;
 
-		if (probe_kernel_address(rom + offset + 0x6, device) != 0)
+		if (get_kernel_nofault(device, rom + offset + 0x6) != 0)
 			continue;
 
 		if (match_id(pdev, vendor, device)) {
@@ -139,8 +139,8 @@ static struct resource *find_oprom(struct pci_dev *pdev)
 			break;
 		}
 
-		if (probe_kernel_address(rom + offset + 0x8, list) == 0 &&
-		    probe_kernel_address(rom + offset + 0xc, rev) == 0 &&
+		if (get_kernel_nofault(list, rom + offset + 0x8) == 0 &&
+		    get_kernel_nofault(rev, rom + offset + 0xc) == 0 &&
 		    rev >= 3 && list &&
 		    probe_list(pdev, vendor, rom + offset + list)) {
 			oprom = res;
@@ -183,14 +183,14 @@ static int __init romsignature(const unsigned char *rom)
 	const unsigned short * const ptr = (const unsigned short *)rom;
 	unsigned short sig;
 
-	return probe_kernel_address(ptr, sig) == 0 && sig == ROMSIGNATURE;
+	return get_kernel_nofault(sig, ptr) == 0 && sig == ROMSIGNATURE;
 }
 
 static int __init romchecksum(const unsigned char *rom, unsigned long length)
 {
 	unsigned char sum, c;
 
-	for (sum = 0; length && probe_kernel_address(rom++, c) == 0; length--)
+	for (sum = 0; length && get_kernel_nofault(c, rom++) == 0; length--)
 		sum += c;
 	return !length && !sum;
 }
@@ -211,7 +211,7 @@ void __init probe_roms(void)
 
 		video_rom_resource.start = start;
 
-		if (probe_kernel_address(rom + 2, c) != 0)
+		if (get_kernel_nofault(c, rom + 2) != 0)
 			continue;
 
 		/* 0 < length <= 0x7f * 512, historically */
@@ -249,7 +249,7 @@ void __init probe_roms(void)
 		if (!romsignature(rom))
 			continue;
 
-		if (probe_kernel_address(rom + 2, c) != 0)
+		if (get_kernel_nofault(c, rom + 2) != 0)
 			continue;
 
 		/* 0 < length <= 0x7f * 512, historically */

arch/x86/kernel/traps.c

@@ -165,7 +165,7 @@ int is_valid_bugaddr(unsigned long addr)
 	if (addr < TASK_SIZE_MAX)
 		return 0;
 
-	if (probe_kernel_address((unsigned short *)addr, ud))
+	if (get_kernel_nofault(ud, (unsigned short *)addr))
 		return 0;
 
 	return ud == INSN_UD0 || ud == INSN_UD2;

arch/x86/mm/fault.c

@@ -97,7 +97,7 @@ check_prefetch_opcode(struct pt_regs *regs, unsigned char *instr,
 		return !instr_lo || (instr_lo>>1) == 1;
 	case 0x00:
 		/* Prefetch instruction is 0x0F0D or 0x0F18 */
-		if (probe_kernel_address(instr, opcode))
+		if (get_kernel_nofault(opcode, instr))
 			return 0;
 
 		*prefetch = (instr_lo == 0xF) &&
@@ -131,7 +131,7 @@ is_prefetch(struct pt_regs *regs, unsigned long error_code, unsigned long addr)
 	while (instr < max_instr) {
 		unsigned char opcode;
 
-		if (probe_kernel_address(instr, opcode))
+		if (get_kernel_nofault(opcode, instr))
 			break;
 
 		instr++;
@@ -440,7 +440,7 @@ static int bad_address(void *p)
 {
 	unsigned long dummy;
 
-	return probe_kernel_address((unsigned long *)p, dummy);
+	return get_kernel_nofault(dummy, (unsigned long *)p);
 }
 
 static void dump_pagetable(unsigned long address)

arch/x86/pci/pcbios.c

@@ -302,7 +302,7 @@ static const struct pci_raw_ops *__init pci_find_bios(void)
 	     check <= (union bios32 *) __va(0xffff0);
 	     ++check) {
 		long sig;
-		if (probe_kernel_address(&check->fields.signature, sig))
+		if (get_kernel_nofault(sig, &check->fields.signature))
 			continue;
 
 		if (check->fields.signature != BIOS32_SIGNATURE)

drivers/soc/qcom/minidump_log.c

@@ -855,7 +855,7 @@ static void md_dump_data(unsigned long addr, int nbytes, const char *name)
 			if (__is_lm_address(p) &&
 			    kern_addr_valid((unsigned long)p) &&
 			    page_accessible(page_to_pfn(virt_to_page(p))) &&
-			    !probe_kernel_address(p, data))
+			    !get_kernel_nofault(data, p))
 				seq_buf_printf(md_cntxt_seq_buf, " %08x",
 						data);
 			else

include/linux/uaccess.h

@@ -322,14 +322,14 @@ long strncpy_from_user_nofault(char *dst, const void __user *unsafe_addr,
 extern long strnlen_unsafe_user(const void __user *unsafe_addr, long count);
 
 /**
- * probe_kernel_address(): safely attempt to read from a location
- * @addr: address to read from
- * @retval: read into this variable
+ * get_kernel_nofault(): safely attempt to read from a location
+ * @val: read into this variable
+ * @ptr: address to read from
  *
  * Returns 0 on success, or -EFAULT.
  */
-#define probe_kernel_address(addr, retval)		\
-	copy_from_kernel_nofault(&retval, addr, sizeof(retval))
+#define get_kernel_nofault(val, ptr)		\
+	copy_from_kernel_nofault(&(val), (ptr), sizeof(val))
 
 #ifndef user_access_begin
 #define user_access_begin(ptr,len) access_ok(ptr, len)