Unverified Commit e8d444d3 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Palmer Dabbelt
Browse files

riscv: remove address space overrides using set_fs() 



Stop providing the possibility to override the address space using
set_fs() now that there is no need for that any more.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarPalmer Dabbelt <palmerdabbelt@google.com>
parent d464118c

arch/riscv/Kconfig

+0 −1
Original line number Diff line number Diff line
@@ -87,7 +87,6 @@ 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

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

+1 −26
Original line number Diff line number Diff line
@@ -26,29 +26,6 @@ 
#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
@@ -76,9 +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;

}



/*

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)