From e8d444d3e98c255f91d228984abc46cfdfaf48b4 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 7 Sep 2020 07:58:25 +0200 Subject: [PATCH] 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: Christoph Hellwig Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 1 - arch/riscv/include/asm/thread_info.h | 6 ------ arch/riscv/include/asm/uaccess.h | 27 +-------------------------- arch/riscv/kernel/process.c | 1 - 4 files changed, 1 insertion(+), 34 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 1046ee7..12642ba 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -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 diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h index 464a2bb..a390711 100644 --- a/arch/riscv/include/asm/thread_info.h +++ b/arch/riscv/include/asm/thread_info.h @@ -24,10 +24,6 @@ #include #include -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__ */ diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h index 264e52f..c47e6b3 100644 --- a/arch/riscv/include/asm/uaccess.h +++ b/arch/riscv/include/asm/uaccess.h @@ -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; } /* diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index 2b97c49..19225ec 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -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) -- 2.7.4