diff options
Diffstat (limited to 'arch/um')
| -rw-r--r-- | arch/um/include/asm/Kbuild | 1 | ||||
| -rw-r--r-- | arch/um/include/asm/mmu_context.h | 29 | ||||
| -rw-r--r-- | arch/um/include/shared/as-layout.h | 3 | ||||
| -rw-r--r-- | arch/um/kernel/exec.c | 4 | ||||
| -rw-r--r-- | arch/um/kernel/skas/mmu.c | 87 | ||||
| -rw-r--r-- | arch/um/kernel/tlb.c | 15 | ||||
| -rw-r--r-- | arch/um/kernel/um_arch.c | 5 | ||||
| -rw-r--r-- | arch/um/os-Linux/skas/process.c | 4 |
8 files changed, 10 insertions, 138 deletions
diff --git a/arch/um/include/asm/Kbuild b/arch/um/include/asm/Kbuild index 314979467db1..a58811dc054c 100644 --- a/arch/um/include/asm/Kbuild +++ b/arch/um/include/asm/Kbuild @@ -25,3 +25,4 @@ generic-y += topology.h generic-y += trace_clock.h generic-y += word-at-a-time.h generic-y += kprobes.h +generic-y += mm_hooks.h diff --git a/arch/um/include/asm/mmu_context.h b/arch/um/include/asm/mmu_context.h index f8a100770691..68e2eb9cfb47 100644 --- a/arch/um/include/asm/mmu_context.h +++ b/arch/um/include/asm/mmu_context.h @@ -10,33 +10,9 @@ #include <linux/mm_types.h> #include <linux/mmap_lock.h> +#include <asm/mm_hooks.h> #include <asm/mmu.h> -extern void uml_setup_stubs(struct mm_struct *mm); -/* - * Needed since we do not use the asm-generic/mm_hooks.h: - */ -static inline int arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm) -{ - uml_setup_stubs(mm); - return 0; -} -extern void arch_exit_mmap(struct mm_struct *mm); -static inline void arch_unmap(struct mm_struct *mm, - unsigned long start, unsigned long end) -{ -} -static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, - bool write, bool execute, bool foreign) -{ - /* by default, allow everything */ - return true; -} - -/* - * end asm-generic/mm_hooks.h functions - */ - extern void force_flush_all(void); #define activate_mm activate_mm @@ -47,9 +23,6 @@ static inline void activate_mm(struct mm_struct *old, struct mm_struct *new) * when the new ->mm is used for the first time. */ __switch_mm(&new->context.id); - mmap_write_lock_nested(new, SINGLE_DEPTH_NESTING); - uml_setup_stubs(new); - mmap_write_unlock(new); } static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, diff --git a/arch/um/include/shared/as-layout.h b/arch/um/include/shared/as-layout.h index 56408bf3480d..9a0bd648d872 100644 --- a/arch/um/include/shared/as-layout.h +++ b/arch/um/include/shared/as-layout.h @@ -20,7 +20,7 @@ * 'UL' and other type specifiers unilaterally. We * use the following macros to deal with this. */ -#define STUB_START 0x100000UL +#define STUB_START stub_start #define STUB_CODE STUB_START #define STUB_DATA (STUB_CODE + UM_KERN_PAGE_SIZE) #define STUB_END (STUB_DATA + UM_KERN_PAGE_SIZE) @@ -46,6 +46,7 @@ extern unsigned long long highmem; extern unsigned long brk_start; extern unsigned long host_task_size; +extern unsigned long stub_start; extern int linux_main(int argc, char **argv); extern void uml_finishsetup(void); diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index e8fd5d540b05..4d8498100341 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -26,9 +26,7 @@ void flush_thread(void) arch_flush_thread(¤t->thread.arch); - ret = unmap(¤t->mm->context.id, 0, STUB_START, 0, &data); - ret = ret || unmap(¤t->mm->context.id, STUB_END, - host_task_size - STUB_END, 1, &data); + ret = unmap(¤t->mm->context.id, 0, TASK_SIZE, 1, &data); if (ret) { printk(KERN_ERR "flush_thread - clearing address space failed, " "err = %d\n", ret); diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c index d9961163da66..125df465e8ea 100644 --- a/arch/um/kernel/skas/mmu.c +++ b/arch/um/kernel/skas/mmu.c @@ -14,47 +14,6 @@ #include <os.h> #include <skas.h> -static int init_stub_pte(struct mm_struct *mm, unsigned long proc, - unsigned long kernel) -{ - pgd_t *pgd; - p4d_t *p4d; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - - pgd = pgd_offset(mm, proc); - - p4d = p4d_alloc(mm, pgd, proc); - if (!p4d) - goto out; - - pud = pud_alloc(mm, p4d, proc); - if (!pud) - goto out_pud; - - pmd = pmd_alloc(mm, pud, proc); - if (!pmd) - goto out_pmd; - - pte = pte_alloc_map(mm, pmd, proc); - if (!pte) - goto out_pte; - - *pte = mk_pte(virt_to_page(kernel), __pgprot(_PAGE_PRESENT)); - *pte = pte_mkread(*pte); - return 0; - - out_pte: - pmd_free(mm, pmd); - out_pmd: - pud_free(mm, pud); - out_pud: - p4d_free(mm, p4d); - out: - return -ENOMEM; -} - int init_new_context(struct task_struct *task, struct mm_struct *mm) { struct mm_context *from_mm = NULL; @@ -98,52 +57,6 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm) return ret; } -void uml_setup_stubs(struct mm_struct *mm) -{ - int err, ret; - - ret = init_stub_pte(mm, STUB_CODE, - (unsigned long) __syscall_stub_start); - if (ret) - goto out; - - ret = init_stub_pte(mm, STUB_DATA, mm->context.id.stack); - if (ret) - goto out; - - mm->context.stub_pages[0] = virt_to_page(__syscall_stub_start); - mm->context.stub_pages[1] = virt_to_page(mm->context.id.stack); - - /* dup_mmap already holds mmap_lock */ - err = install_special_mapping(mm, STUB_START, STUB_END - STUB_START, - VM_READ | VM_MAYREAD | VM_EXEC | - VM_MAYEXEC | VM_DONTCOPY | VM_PFNMAP, - mm->context.stub_pages); - if (err) { - printk(KERN_ERR "install_special_mapping returned %d\n", err); - goto out; - } - return; - -out: - force_sigsegv(SIGSEGV); -} - -void arch_exit_mmap(struct mm_struct *mm) -{ - pte_t *pte; - - pte = virt_to_pte(mm, STUB_CODE); - if (pte != NULL) - pte_clear(mm, STUB_CODE, pte); - - pte = virt_to_pte(mm, STUB_DATA); - if (pte == NULL) - return; - - pte_clear(mm, STUB_DATA, pte); -} - void destroy_context(struct mm_struct *mm) { struct mm_context *mmu = &mm->context; diff --git a/arch/um/kernel/tlb.c b/arch/um/kernel/tlb.c index 5be1b0da9f3b..bc38f79ca3a3 100644 --- a/arch/um/kernel/tlb.c +++ b/arch/um/kernel/tlb.c @@ -125,9 +125,6 @@ static int add_mmap(unsigned long virt, unsigned long phys, unsigned long len, struct host_vm_op *last; int fd = -1, ret = 0; - if (virt + len > STUB_START && virt < STUB_END) - return -EINVAL; - if (hvc->userspace) fd = phys_mapping(phys, &offset); else @@ -165,9 +162,6 @@ static int add_munmap(unsigned long addr, unsigned long len, struct host_vm_op *last; int ret = 0; - if (addr + len > STUB_START && addr < STUB_END) - return -EINVAL; - if (hvc->index != 0) { last = &hvc->ops[hvc->index - 1]; if ((last->type == MUNMAP) && @@ -195,9 +189,6 @@ static int add_mprotect(unsigned long addr, unsigned long len, struct host_vm_op *last; int ret = 0; - if (addr + len > STUB_START && addr < STUB_END) - return -EINVAL; - if (hvc->index != 0) { last = &hvc->ops[hvc->index - 1]; if ((last->type == MPROTECT) && @@ -232,9 +223,6 @@ static inline int update_pte_range(pmd_t *pmd, unsigned long addr, pte = pte_offset_kernel(pmd, addr); do { - if ((addr >= STUB_START) && (addr < STUB_END)) - continue; - r = pte_read(*pte); w = pte_write(*pte); x = pte_exec(*pte); @@ -478,9 +466,6 @@ void flush_tlb_page(struct vm_area_struct *vma, unsigned long address) address &= PAGE_MASK; - if (address >= STUB_START && address < STUB_END) - goto kill; - pgd = pgd_offset(mm, address); if (!pgd_present(*pgd)) goto kill; diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c index 80e2660782a0..74e07e748a9b 100644 --- a/arch/um/kernel/um_arch.c +++ b/arch/um/kernel/um_arch.c @@ -249,6 +249,7 @@ void uml_finishsetup(void) } /* Set during early boot */ +unsigned long stub_start; unsigned long task_size; EXPORT_SYMBOL(task_size); @@ -283,6 +284,10 @@ int __init linux_main(int argc, char **argv) add_arg(DEFAULT_COMMAND_LINE_CONSOLE); host_task_size = os_get_top_address(); + /* reserve two pages for the stubs */ + host_task_size -= 2 * PAGE_SIZE; + stub_start = host_task_size; + /* * TASK_SIZE needs to be PGDIR_SIZE aligned or else exit_mmap craps * out diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c index 623b0aeadf4c..fba674fac8b7 100644 --- a/arch/um/os-Linux/skas/process.c +++ b/arch/um/os-Linux/skas/process.c @@ -251,10 +251,6 @@ static int userspace_tramp(void *stack) signal(SIGTERM, SIG_DFL); signal(SIGWINCH, SIG_IGN); - /* - * This has a pte, but it can't be mapped in with the usual - * tlb_flush mechanism because this is part of that mechanism - */ fd = phys_mapping(to_phys(__syscall_stub_start), &offset); addr = mmap64((void *) STUB_CODE, UM_KERN_PAGE_SIZE, PROT_EXEC, MAP_FIXED | MAP_PRIVATE, fd, offset); |