Commit 0593c1b4 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'riscv-for-linus-5.10-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux 

Pull more RISC-V updates from Palmer Dabbelt:
 "Just a single patch set: the remainder of Christoph's work to remove
  set_fs, including the RISC-V portion"

* tag 'riscv-for-linus-5.10-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: remove address space overrides using set_fs()
  riscv: implement __get_kernel_nofault and __put_user_nofault
  riscv: refactor __get_user and __put_user
  riscv: use memcpy based uaccess for nommu again
  asm-generic: make the set_fs implementation optional
  asm-generic: add nommu implementations of __{get,put}_kernel_nofault
  asm-generic: improve the nommu {get,put}_user handling
  uaccess: provide a generic TASK_SIZE_MAX definition
parents 45fe6058 e8d444d3

arch/riscv/Kconfig

+1 −1
Original line number Diff line number Diff line
@@ -88,7 +88,7 @@ config RISCV 
	select SPARSE_IRQ

	select SYSCTL_EXCEPTION_TRACE

	select THREAD_INFO_IN_TASK

	select SET_FS

	select UACCESS_MEMCPY if !MMU



config ARCH_MMAP_RND_BITS_MIN

	default 18 if 64BIT

arch/riscv/include/asm/thread_info.h

+0 −6
Original line number Diff line number Diff line
@@ -24,10 +24,6 @@ 
#include <asm/processor.h>

#include <asm/csr.h>



typedef struct {

	unsigned long seg;

} mm_segment_t;



/*

 * low level task data that entry.S needs immediate access to

 * - this struct should fit entirely inside of one cache line
@@ -39,7 +35,6 @@ typedef struct { 
struct thread_info {

	unsigned long		flags;		/* low level flags */

	int                     preempt_count;  /* 0=>preemptible, <0=>BUG */

	mm_segment_t		addr_limit;

	/*

	 * These stack pointers are overwritten on every system call or

	 * exception.  SP is also saved to the stack it can be recovered when
@@ -59,7 +54,6 @@ struct thread_info { 
{						\

	.flags		= 0,			\

	.preempt_count	= INIT_PREEMPT_COUNT,	\

	.addr_limit	= KERNEL_DS,		\

}



#endif /* !__ASSEMBLY__ */

arch/riscv/include/asm/uaccess.h

+91 −86
Original line number Diff line number Diff line
@@ -13,24 +13,6 @@ 
/*

 * User space memory access functions

 */



extern unsigned long __must_check __asm_copy_to_user(void __user *to,

	const void *from, unsigned long n);

extern unsigned long __must_check __asm_copy_from_user(void *to,

	const void __user *from, unsigned long n);



static inline unsigned long

raw_copy_from_user(void *to, const void __user *from, unsigned long n)

{

	return __asm_copy_from_user(to, from, n);

}



static inline unsigned long

raw_copy_to_user(void __user *to, const void *from, unsigned long n)

{

	return __asm_copy_to_user(to, from, n);

}



#ifdef CONFIG_MMU

#include <linux/errno.h>

#include <linux/compiler.h>
@@ -44,29 +26,6 @@ raw_copy_to_user(void __user *to, const void *from, unsigned long n) 
#define __disable_user_access()							\

	__asm__ __volatile__ ("csrc sstatus, %0" : : "r" (SR_SUM) : "memory")



/*

 * The fs value determines whether argument validity checking should be

 * performed or not.  If get_fs() == USER_DS, checking is performed, with

 * get_fs() == KERNEL_DS, checking is bypassed.

 *

 * For historical reasons, these macros are grossly misnamed.

 */



#define MAKE_MM_SEG(s)	((mm_segment_t) { (s) })



#define KERNEL_DS	MAKE_MM_SEG(~0UL)

#define USER_DS		MAKE_MM_SEG(TASK_SIZE)



#define get_fs()	(current_thread_info()->addr_limit)



static inline void set_fs(mm_segment_t fs)

{

	current_thread_info()->addr_limit = fs;

}



#define uaccess_kernel() (get_fs().seg == KERNEL_DS.seg)

#define user_addr_max()	(get_fs().seg)



/**

 * access_ok: - Checks if a user space pointer is valid

 * @addr: User space pointer to start of block to check
@@ -94,9 +53,7 @@ static inline void set_fs(mm_segment_t fs) 
 */

static inline int __access_ok(unsigned long addr, unsigned long size)

{

	const mm_segment_t fs = get_fs();



	return size <= fs.seg && addr <= fs.seg - size;

	return size <= TASK_SIZE && addr <= TASK_SIZE - size;

}



/*
@@ -125,7 +82,6 @@ static inline int __access_ok(unsigned long addr, unsigned long size) 
do {								\

	uintptr_t __tmp;					\

	__typeof__(x) __x;					\

	__enable_user_access();					\

	__asm__ __volatile__ (					\

		"1:\n"						\

		"	" insn " %1, %3\n"			\
@@ -143,7 +99,6 @@ do { \ 
		"	.previous"				\

		: "+r" (err), "=&r" (__x), "=r" (__tmp)		\

		: "m" (*(ptr)), "i" (-EFAULT));			\

	__disable_user_access();				\

	(x) = __x;						\

} while (0)
@@ -156,7 +111,6 @@ do { \ 
	u32 __user *__ptr = (u32 __user *)(ptr);		\

	u32 __lo, __hi;						\

	uintptr_t __tmp;					\

	__enable_user_access();					\

	__asm__ __volatile__ (					\

		"1:\n"						\

		"	lw %1, %4\n"				\
@@ -180,12 +134,30 @@ do { \ 
			"=r" (__tmp)				\

		: "m" (__ptr[__LSW]), "m" (__ptr[__MSW]),	\

			"i" (-EFAULT));				\

	__disable_user_access();				\

	(x) = (__typeof__(x))((__typeof__((x)-(x)))(		\

		(((u64)__hi << 32) | __lo)));			\

} while (0)

#endif /* CONFIG_64BIT */



#define __get_user_nocheck(x, __gu_ptr, __gu_err)		\

do {								\

	switch (sizeof(*__gu_ptr)) {				\

	case 1:							\

		__get_user_asm("lb", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 2:							\

		__get_user_asm("lh", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 4:							\

		__get_user_asm("lw", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 8:							\

		__get_user_8((x), __gu_ptr, __gu_err);	\

		break;						\

	default:						\

		BUILD_BUG();					\

	}							\

} while (0)



/**

 * __get_user: - Get a simple variable from user space, with less checking.
@@ -209,25 +181,15 @@ do { \ 
 */

#define __get_user(x, ptr)					\

({								\

	register long __gu_err = 0;				\

	const __typeof__(*(ptr)) __user *__gu_ptr = (ptr);	\

	long __gu_err = 0;					\

								\

	__chk_user_ptr(__gu_ptr);				\

	switch (sizeof(*__gu_ptr)) {				\

	case 1:							\

		__get_user_asm("lb", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 2:							\

		__get_user_asm("lh", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 4:							\

		__get_user_asm("lw", (x), __gu_ptr, __gu_err);	\

		break;						\

	case 8:							\

		__get_user_8((x), __gu_ptr, __gu_err);	\

		break;						\

	default:						\

		BUILD_BUG();					\

	}							\

								\

	__enable_user_access();					\

	__get_user_nocheck(x, __gu_ptr, __gu_err);		\

	__disable_user_access();				\

								\

	__gu_err;						\

})
@@ -261,7 +223,6 @@ do { \ 
do {								\

	uintptr_t __tmp;					\

	__typeof__(*(ptr)) __x = x;				\

	__enable_user_access();					\

	__asm__ __volatile__ (					\

		"1:\n"						\

		"	" insn " %z3, %2\n"			\
@@ -278,7 +239,6 @@ do { \ 
		"	.previous"				\

		: "+r" (err), "=r" (__tmp), "=m" (*(ptr))	\

		: "rJ" (__x), "i" (-EFAULT));			\

	__disable_user_access();				\

} while (0)



#ifdef CONFIG_64BIT
@@ -290,7 +250,6 @@ do { \ 
	u32 __user *__ptr = (u32 __user *)(ptr);		\

	u64 __x = (__typeof__((x)-(x)))(x);			\

	uintptr_t __tmp;					\

	__enable_user_access();					\

	__asm__ __volatile__ (					\

		"1:\n"						\

		"	sw %z4, %2\n"				\
@@ -312,10 +271,28 @@ do { \ 
			"=m" (__ptr[__LSW]),			\

			"=m" (__ptr[__MSW])			\

		: "rJ" (__x), "rJ" (__x >> 32), "i" (-EFAULT));	\

	__disable_user_access();				\

} while (0)

#endif /* CONFIG_64BIT */



#define __put_user_nocheck(x, __gu_ptr, __pu_err)					\

do {								\

	switch (sizeof(*__gu_ptr)) {				\

	case 1:							\

		__put_user_asm("sb", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 2:							\

		__put_user_asm("sh", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 4:							\

		__put_user_asm("sw", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 8:							\

		__put_user_8((x), __gu_ptr, __pu_err);	\

		break;						\

	default:						\

		BUILD_BUG();					\

	}							\

} while (0)



/**

 * __put_user: - Write a simple value into user space, with less checking.
@@ -338,25 +315,15 @@ do { \ 
 */

#define __put_user(x, ptr)					\

({								\

	register long __pu_err = 0;				\

	__typeof__(*(ptr)) __user *__gu_ptr = (ptr);		\

	long __pu_err = 0;					\

								\

	__chk_user_ptr(__gu_ptr);				\

	switch (sizeof(*__gu_ptr)) {				\

	case 1:							\

		__put_user_asm("sb", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 2:							\

		__put_user_asm("sh", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 4:							\

		__put_user_asm("sw", (x), __gu_ptr, __pu_err);	\

		break;						\

	case 8:							\

		__put_user_8((x), __gu_ptr, __pu_err);	\

		break;						\

	default:						\

		BUILD_BUG();					\

	}							\

								\

	__enable_user_access();					\

	__put_user_nocheck(x, __gu_ptr, __pu_err);		\

	__disable_user_access();				\

								\

	__pu_err;						\

})
@@ -385,6 +352,24 @@ do { \ 
		-EFAULT;					\

})





unsigned long __must_check __asm_copy_to_user(void __user *to,

	const void *from, unsigned long n);

unsigned long __must_check __asm_copy_from_user(void *to,

	const void __user *from, unsigned long n);



static inline unsigned long

raw_copy_from_user(void *to, const void __user *from, unsigned long n)

{

	return __asm_copy_from_user(to, from, n);

}



static inline unsigned long

raw_copy_to_user(void __user *to, const void *from, unsigned long n)

{

	return __asm_copy_to_user(to, from, n);

}



extern long strncpy_from_user(char *dest, const char __user *src, long count);



extern long __must_check strlen_user(const char __user *str);
@@ -476,6 +461,26 @@ unsigned long __must_check clear_user(void __user *to, unsigned long n) 
	__ret;							\

})



#define HAVE_GET_KERNEL_NOFAULT



#define __get_kernel_nofault(dst, src, type, err_label)			\

do {									\

	long __kr_err;							\

									\

	__get_user_nocheck(*((type *)(dst)), (type *)(src), __kr_err);	\

	if (unlikely(__kr_err))						\

		goto err_label;						\

} while (0)



#define __put_kernel_nofault(dst, src, type, err_label)			\

do {									\

	long __kr_err;							\

									\

	__put_user_nocheck(*((type *)(dst)), (type *)(src), __kr_err);	\

	if (unlikely(__kr_err))						\

		goto err_label;						\

} while (0)



#else /* CONFIG_MMU */

#include <asm-generic/uaccess.h>

#endif /* CONFIG_MMU */

arch/riscv/kernel/process.c

+0 −1
Original line number Diff line number Diff line
@@ -84,7 +84,6 @@ void start_thread(struct pt_regs *regs, unsigned long pc, 
	}

	regs->epc = pc;

	regs->sp = sp;

	set_fs(USER_DS);

}



void flush_thread(void)

arch/riscv/lib/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -2,5 +2,5 @@ 
lib-y			+= delay.o

lib-y			+= memcpy.o

lib-y			+= memset.o

lib-y			+= uaccess.o

lib-$(CONFIG_MMU)	+= uaccess.o

lib-$(CONFIG_64BIT)	+= tishift.o

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