diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/memory.c | 2 | ||||
| -rw-r--r-- | mm/nommu.c | 52 | ||||
| -rw-r--r-- | mm/percpu.c | 3 |
3 files changed, 41 insertions, 16 deletions
diff --git a/mm/memory.c b/mm/memory.c index 51a5c23704af..9da8cab1b1b0 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3715,7 +3715,7 @@ static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, } /** - * @access_remote_vm - access another process' address space + * access_remote_vm - access another process' address space * @mm: the mm_struct of the target address space * @addr: start address to access * @buf: source or destination buffer diff --git a/mm/nommu.c b/mm/nommu.c index cb86e7d5e7f5..c4c542c736a9 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1971,21 +1971,10 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) } EXPORT_SYMBOL(filemap_fault); -/* - * Access another process' address space. - * - source/target buffer must be kernel space - */ -int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write) +static int __access_remote_vm(struct task_struct *tsk, struct mm_struct *mm, + unsigned long addr, void *buf, int len, int write) { struct vm_area_struct *vma; - struct mm_struct *mm; - - if (addr + len < addr) - return 0; - - mm = get_task_mm(tsk); - if (!mm) - return 0; down_read(&mm->mmap_sem); @@ -2010,6 +1999,43 @@ int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, in } up_read(&mm->mmap_sem); + + return len; +} + +/** + * @access_remote_vm - access another process' address space + * @mm: the mm_struct of the target address space + * @addr: start address to access + * @buf: source or destination buffer + * @len: number of bytes to transfer + * @write: whether the access is a write + * + * The caller must hold a reference on @mm. + */ +int access_remote_vm(struct mm_struct *mm, unsigned long addr, + void *buf, int len, int write) +{ + return __access_remote_vm(NULL, mm, addr, buf, len, write); +} + +/* + * Access another process' address space. + * - source/target buffer must be kernel space + */ +int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write) +{ + struct mm_struct *mm; + + if (addr + len < addr) + return 0; + + mm = get_task_mm(tsk); + if (!mm) + return 0; + + len = __access_remote_vm(tsk, mm, addr, buf, len, write); + mmput(mm); return len; } diff --git a/mm/percpu.c b/mm/percpu.c index 3f930018aa60..55d4d113fbd3 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -1008,8 +1008,7 @@ phys_addr_t per_cpu_ptr_to_phys(void *addr) } if (in_first_chunk) { - if ((unsigned long)addr < VMALLOC_START || - (unsigned long)addr >= VMALLOC_END) + if (!is_vmalloc_addr(addr)) return __pa(addr); else return page_to_phys(vmalloc_to_page(addr)); |