From 967747bbc084b93b54e66f9047d342232314cd25 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 11 Feb 2022 21:42:45 +0100 Subject: uaccess: remove CONFIG_SET_FS There are no remaining callers of set_fs(), so CONFIG_SET_FS can be removed globally, along with the thread_info field and any references to it. This turns access_ok() into a cheaper check against TASK_SIZE_MAX. As CONFIG_SET_FS is now gone, drop all remaining references to set_fs()/get_fs(), mm_segment_t, user_addr_max() and uaccess_kernel(). Acked-by: Sam Ravnborg # for sparc32 changes Acked-by: "Eric W. Biederman" Tested-by: Sergey Matyukevich # for arc changes Acked-by: Stafford Horne # [openrisc, asm-generic] Acked-by: Dinh Nguyen Signed-off-by: Arnd Bergmann --- arch/xtensa/Kconfig | 1 - arch/xtensa/include/asm/asm-uaccess.h | 71 ----------------------------------- arch/xtensa/include/asm/processor.h | 7 ---- arch/xtensa/include/asm/thread_info.h | 3 -- arch/xtensa/include/asm/uaccess.h | 16 -------- arch/xtensa/kernel/asm-offsets.c | 3 -- 6 files changed, 101 deletions(-) (limited to 'arch/xtensa') diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index 8ac599aa6d99..09f7616a0b46 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -40,7 +40,6 @@ config XTENSA select IRQ_DOMAIN select MODULES_USE_ELF_RELA select PERF_USE_VMALLOC - select SET_FS select TRACE_IRQFLAGS_SUPPORT select VIRT_TO_BUS help diff --git a/arch/xtensa/include/asm/asm-uaccess.h b/arch/xtensa/include/asm/asm-uaccess.h index 7f6cf4151843..7cec869136e3 100644 --- a/arch/xtensa/include/asm/asm-uaccess.h +++ b/arch/xtensa/include/asm/asm-uaccess.h @@ -23,76 +23,6 @@ #include #include -/* - * These assembly macros mirror the C macros in asm/uaccess.h. They - * should always have identical functionality. See - * arch/xtensa/kernel/sys.S for usage. - */ - -#define KERNEL_DS 0 -#define USER_DS 1 - -/* - * get_fs reads current->thread.current_ds into a register. - * On Entry: - * anything - * stack - * On Exit: - * contains current->thread.current_ds - */ - .macro get_fs ad, sp - GET_CURRENT(\ad,\sp) -#if THREAD_CURRENT_DS > 1020 - addi \ad, \ad, TASK_THREAD - l32i \ad, \ad, THREAD_CURRENT_DS - TASK_THREAD -#else - l32i \ad, \ad, THREAD_CURRENT_DS -#endif - .endm - -/* - * set_fs sets current->thread.current_ds to some value. - * On Entry: - * anything (temp register) - * value to write - * stack - * On Exit: - * destroyed (actually, current) - * preserved, value to write - */ - .macro set_fs at, av, sp - GET_CURRENT(\at,\sp) - s32i \av, \at, THREAD_CURRENT_DS - .endm - -/* - * kernel_ok determines whether we should bypass addr/size checking. - * See the equivalent C-macro version below for clarity. - * On success, kernel_ok branches to a label indicated by parameter - * . This implies that the macro falls through to the next - * insruction on an error. - * - * Note that while this macro can be used independently, we designed - * in for optimal use in the access_ok macro below (i.e., we fall - * through on error). - * - * On Entry: - * anything (temp register) - * label to branch to on success; implies - * fall-through macro on error - * stack pointer - * On Exit: - * destroyed (actually, current->thread.current_ds) - */ - -#if ((KERNEL_DS != 0) || (USER_DS == 0)) -# error Assembly macro kernel_ok fails -#endif - .macro kernel_ok at, sp, success - get_fs \at, \sp - beqz \at, \success - .endm - /* * user_ok determines whether the access to user-space memory is allowed. * See the equivalent C-macro version below for clarity. @@ -147,7 +77,6 @@ * destroyed */ .macro access_ok aa, as, at, sp, error - kernel_ok \at, \sp, .Laccess_ok_\@ user_ok \aa, \as, \at, \error .Laccess_ok_\@: .endm diff --git a/arch/xtensa/include/asm/processor.h b/arch/xtensa/include/asm/processor.h index 37d3e9887fe7..abad7c3df46f 100644 --- a/arch/xtensa/include/asm/processor.h +++ b/arch/xtensa/include/asm/processor.h @@ -152,18 +152,12 @@ */ #define SPILL_SLOT_CALL12(sp, reg) (*(((unsigned long *)(sp)) - 16 + (reg))) -typedef struct { - unsigned long seg; -} mm_segment_t; - struct thread_struct { /* kernel's return address and stack pointer for context switching */ unsigned long ra; /* kernel's a0: return address and window call size */ unsigned long sp; /* kernel's a1: stack pointer */ - mm_segment_t current_ds; /* see uaccess.h for example uses */ - /* struct xtensa_cpuinfo info; */ unsigned long bad_vaddr; /* last user fault */ @@ -186,7 +180,6 @@ struct thread_struct { { \ ra: 0, \ sp: sizeof(init_stack) + (long) &init_stack, \ - current_ds: {0}, \ /*info: {0}, */ \ bad_vaddr: 0, \ bad_uaddr: 0, \ diff --git a/arch/xtensa/include/asm/thread_info.h b/arch/xtensa/include/asm/thread_info.h index a312333a9add..f6fcbba1d02f 100644 --- a/arch/xtensa/include/asm/thread_info.h +++ b/arch/xtensa/include/asm/thread_info.h @@ -52,8 +52,6 @@ struct thread_info { __u32 cpu; /* current CPU */ __s32 preempt_count; /* 0 => preemptable,< 0 => BUG*/ - mm_segment_t addr_limit; /* thread address space */ - unsigned long cpenable; #if XCHAL_HAVE_EXCLUSIVE /* result of the most recent exclusive store */ @@ -81,7 +79,6 @@ struct thread_info { .flags = 0, \ .cpu = 0, \ .preempt_count = INIT_PREEMPT_COUNT, \ - .addr_limit = KERNEL_DS, \ } /* how to get the thread information struct from C */ diff --git a/arch/xtensa/include/asm/uaccess.h b/arch/xtensa/include/asm/uaccess.h index 0edd9e4b23d0..56aec6d504fe 100644 --- a/arch/xtensa/include/asm/uaccess.h +++ b/arch/xtensa/include/asm/uaccess.h @@ -19,22 +19,6 @@ #include #include #include - -/* - * 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 (Data Segment Register?), these macros are - * grossly misnamed. - */ - -#define KERNEL_DS ((mm_segment_t) { 0 }) -#define USER_DS ((mm_segment_t) { 1 }) - -#define get_fs() (current->thread.current_ds) -#define set_fs(val) (current->thread.current_ds = (val)) - #include /* diff --git a/arch/xtensa/kernel/asm-offsets.c b/arch/xtensa/kernel/asm-offsets.c index dc5c83cad9be..f1fd1390d069 100644 --- a/arch/xtensa/kernel/asm-offsets.c +++ b/arch/xtensa/kernel/asm-offsets.c @@ -87,7 +87,6 @@ int main(void) OFFSET(TI_STSTUS, thread_info, status); OFFSET(TI_CPU, thread_info, cpu); OFFSET(TI_PRE_COUNT, thread_info, preempt_count); - OFFSET(TI_ADDR_LIMIT, thread_info, addr_limit); /* struct thread_info (offset from start_struct) */ DEFINE(THREAD_RA, offsetof (struct task_struct, thread.ra)); @@ -108,8 +107,6 @@ int main(void) #endif DEFINE(THREAD_XTREGS_USER, offsetof (struct thread_info, xtregs_user)); DEFINE(XTREGS_USER_SIZE, sizeof(xtregs_user_t)); - DEFINE(THREAD_CURRENT_DS, offsetof (struct task_struct, \ - thread.current_ds)); /* struct mm_struct */ DEFINE(MM_USERS, offsetof(struct mm_struct, mm_users)); -- cgit