diff options
Diffstat (limited to 'mm/migrate.c')
-rw-r--r-- | mm/migrate.c | 87 |
1 files changed, 48 insertions, 39 deletions
diff --git a/mm/migrate.c b/mm/migrate.c index 04a98bb2f568..5ca5842df5db 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -381,7 +381,7 @@ static int expected_page_refs(struct address_space *mapping, struct page *page) int expected_count = 1; /* - * Device public or private pages have an extra refcount as they are + * Device private pages have an extra refcount as they are * ZONE_DEVICE pages. */ expected_count += is_device_private_page(page); @@ -503,7 +503,7 @@ int migrate_page_move_mapping(struct address_space *mapping, __dec_lruvec_state(old_lruvec, NR_SHMEM); __inc_lruvec_state(new_lruvec, NR_SHMEM); } - if (dirty && mapping_cap_account_dirty(mapping)) { + if (dirty && mapping_can_writeback(mapping)) { __dec_node_state(oldzone->zone_pgdat, NR_FILE_DIRTY); __dec_zone_state(oldzone, NR_ZONE_WRITE_PENDING); __inc_node_state(newzone->zone_pgdat, NR_FILE_DIRTY); @@ -1223,16 +1223,11 @@ out: * we want to retry. */ if (rc == MIGRATEPAGE_SUCCESS) { - put_page(page); - if (reason == MR_MEMORY_FAILURE) { + if (reason != MR_MEMORY_FAILURE) /* - * Set PG_HWPoison on just freed page - * intentionally. Although it's rather weird, - * it's how HWPoison flag works at the moment. + * We release the page in page_handle_poison. */ - if (set_hwpoison_free_buddy_page(page)) - num_poisoned_pages_inc(); - } + put_page(page); } else { if (rc != -EAGAIN) { if (likely(!__PageMovable(page))) { @@ -1869,33 +1864,27 @@ static int do_pages_stat(struct mm_struct *mm, unsigned long nr_pages, return nr_pages ? -EFAULT : 0; } -/* - * Move a list of pages in the address space of the currently executing - * process. - */ -static int kernel_move_pages(pid_t pid, unsigned long nr_pages, - const void __user * __user *pages, - const int __user *nodes, - int __user *status, int flags) +static struct mm_struct *find_mm_struct(pid_t pid, nodemask_t *mem_nodes) { struct task_struct *task; struct mm_struct *mm; - int err; - nodemask_t task_nodes; - /* Check flags */ - if (flags & ~(MPOL_MF_MOVE|MPOL_MF_MOVE_ALL)) - return -EINVAL; - - if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE)) - return -EPERM; + /* + * There is no need to check if current process has the right to modify + * the specified process when they are same. + */ + if (!pid) { + mmget(current->mm); + *mem_nodes = cpuset_mems_allowed(current); + return current->mm; + } /* Find the mm_struct */ rcu_read_lock(); - task = pid ? find_task_by_vpid(pid) : current; + task = find_task_by_vpid(pid); if (!task) { rcu_read_unlock(); - return -ESRCH; + return ERR_PTR(-ESRCH); } get_task_struct(task); @@ -1905,22 +1894,47 @@ static int kernel_move_pages(pid_t pid, unsigned long nr_pages, */ if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) { rcu_read_unlock(); - err = -EPERM; + mm = ERR_PTR(-EPERM); goto out; } rcu_read_unlock(); - err = security_task_movememory(task); - if (err) + mm = ERR_PTR(security_task_movememory(task)); + if (IS_ERR(mm)) goto out; - - task_nodes = cpuset_mems_allowed(task); + *mem_nodes = cpuset_mems_allowed(task); mm = get_task_mm(task); +out: put_task_struct(task); - if (!mm) + mm = ERR_PTR(-EINVAL); + return mm; +} + +/* + * Move a list of pages in the address space of the currently executing + * process. + */ +static int kernel_move_pages(pid_t pid, unsigned long nr_pages, + const void __user * __user *pages, + const int __user *nodes, + int __user *status, int flags) +{ + struct mm_struct *mm; + int err; + nodemask_t task_nodes; + + /* Check flags */ + if (flags & ~(MPOL_MF_MOVE|MPOL_MF_MOVE_ALL)) return -EINVAL; + if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE)) + return -EPERM; + + mm = find_mm_struct(pid, &task_nodes); + if (IS_ERR(mm)) + return PTR_ERR(mm); + if (nodes) err = do_pages_move(mm, task_nodes, nr_pages, pages, nodes, status, flags); @@ -1929,10 +1943,6 @@ static int kernel_move_pages(pid_t pid, unsigned long nr_pages, mmput(mm); return err; - -out: - put_task_struct(task); - return err; } SYSCALL_DEFINE6(move_pages, pid_t, pid, unsigned long, nr_pages, @@ -3077,7 +3087,6 @@ void migrate_vma_finalize(struct migrate_vma *migrate) remove_migration_ptes(page, newpage, false); unlock_page(page); - migrate->cpages--; if (is_zone_device_page(page)) put_page(page); |