Merge tag 'char-misc-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregk...
[cascardo/linux.git] / mm / nommu.c
index 541bed6..7296360 100644 (file)
@@ -214,6 +214,39 @@ long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 }
 EXPORT_SYMBOL(get_user_pages);
 
+long get_user_pages_locked(struct task_struct *tsk, struct mm_struct *mm,
+                          unsigned long start, unsigned long nr_pages,
+                          int write, int force, struct page **pages,
+                          int *locked)
+{
+       return get_user_pages(tsk, mm, start, nr_pages, write, force,
+                             pages, NULL);
+}
+EXPORT_SYMBOL(get_user_pages_locked);
+
+long __get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
+                              unsigned long start, unsigned long nr_pages,
+                              int write, int force, struct page **pages,
+                              unsigned int gup_flags)
+{
+       long ret;
+       down_read(&mm->mmap_sem);
+       ret = get_user_pages(tsk, mm, start, nr_pages, write, force,
+                            pages, NULL);
+       up_read(&mm->mmap_sem);
+       return ret;
+}
+EXPORT_SYMBOL(__get_user_pages_unlocked);
+
+long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
+                            unsigned long start, unsigned long nr_pages,
+                            int write, int force, struct page **pages)
+{
+       return __get_user_pages_unlocked(tsk, mm, start, nr_pages, write,
+                                        force, pages, 0);
+}
+EXPORT_SYMBOL(get_user_pages_unlocked);
+
 /**
  * follow_pfn - look up PFN at a user virtual address
  * @vma: memory mapping
@@ -947,9 +980,6 @@ static int validate_mmap_request(struct file *file,
                return -EOVERFLOW;
 
        if (file) {
-               /* validate file mapping requests */
-               struct address_space *mapping;
-
                /* files must support mmap */
                if (!file->f_op->mmap)
                        return -ENODEV;
@@ -958,28 +988,22 @@ static int validate_mmap_request(struct file *file,
                 * - we support chardevs that provide their own "memory"
                 * - we support files/blockdevs that are memory backed
                 */
-               mapping = file->f_mapping;
-               if (!mapping)
-                       mapping = file_inode(file)->i_mapping;
-
-               capabilities = 0;
-               if (mapping && mapping->backing_dev_info)
-                       capabilities = mapping->backing_dev_info->capabilities;
-
-               if (!capabilities) {
+               if (file->f_op->mmap_capabilities) {
+                       capabilities = file->f_op->mmap_capabilities(file);
+               } else {
                        /* no explicit capabilities set, so assume some
                         * defaults */
                        switch (file_inode(file)->i_mode & S_IFMT) {
                        case S_IFREG:
                        case S_IFBLK:
-                               capabilities = BDI_CAP_MAP_COPY;
+                               capabilities = NOMMU_MAP_COPY;
                                break;
 
                        case S_IFCHR:
                                capabilities =
-                                       BDI_CAP_MAP_DIRECT |
-                                       BDI_CAP_READ_MAP |
-                                       BDI_CAP_WRITE_MAP;
+                                       NOMMU_MAP_DIRECT |
+                                       NOMMU_MAP_READ |
+                                       NOMMU_MAP_WRITE;
                                break;
 
                        default:
@@ -990,9 +1014,9 @@ static int validate_mmap_request(struct file *file,
                /* eliminate any capabilities that we can't support on this
                 * device */
                if (!file->f_op->get_unmapped_area)
-                       capabilities &= ~BDI_CAP_MAP_DIRECT;
+                       capabilities &= ~NOMMU_MAP_DIRECT;
                if (!file->f_op->read)
-                       capabilities &= ~BDI_CAP_MAP_COPY;
+                       capabilities &= ~NOMMU_MAP_COPY;
 
                /* The file shall have been opened with read permission. */
                if (!(file->f_mode & FMODE_READ))
@@ -1011,29 +1035,29 @@ static int validate_mmap_request(struct file *file,
                        if (locks_verify_locked(file))
                                return -EAGAIN;
 
-                       if (!(capabilities & BDI_CAP_MAP_DIRECT))
+                       if (!(capabilities & NOMMU_MAP_DIRECT))
                                return -ENODEV;
 
                        /* we mustn't privatise shared mappings */
-                       capabilities &= ~BDI_CAP_MAP_COPY;
+                       capabilities &= ~NOMMU_MAP_COPY;
                } else {
                        /* we're going to read the file into private memory we
                         * allocate */
-                       if (!(capabilities & BDI_CAP_MAP_COPY))
+                       if (!(capabilities & NOMMU_MAP_COPY))
                                return -ENODEV;
 
                        /* we don't permit a private writable mapping to be
                         * shared with the backing device */
                        if (prot & PROT_WRITE)
-                               capabilities &= ~BDI_CAP_MAP_DIRECT;
+                               capabilities &= ~NOMMU_MAP_DIRECT;
                }
 
-               if (capabilities & BDI_CAP_MAP_DIRECT) {
-                       if (((prot & PROT_READ)  && !(capabilities & BDI_CAP_READ_MAP))  ||
-                           ((prot & PROT_WRITE) && !(capabilities & BDI_CAP_WRITE_MAP)) ||
-                           ((prot & PROT_EXEC)  && !(capabilities & BDI_CAP_EXEC_MAP))
+               if (capabilities & NOMMU_MAP_DIRECT) {
+                       if (((prot & PROT_READ)  && !(capabilities & NOMMU_MAP_READ))  ||
+                           ((prot & PROT_WRITE) && !(capabilities & NOMMU_MAP_WRITE)) ||
+                           ((prot & PROT_EXEC)  && !(capabilities & NOMMU_MAP_EXEC))
                            ) {
-                               capabilities &= ~BDI_CAP_MAP_DIRECT;
+                               capabilities &= ~NOMMU_MAP_DIRECT;
                                if (flags & MAP_SHARED) {
                                        printk(KERN_WARNING
                                               "MAP_SHARED not completely supported on !MMU\n");
@@ -1050,21 +1074,21 @@ static int validate_mmap_request(struct file *file,
                } else if ((prot & PROT_READ) && !(prot & PROT_EXEC)) {
                        /* handle implication of PROT_EXEC by PROT_READ */
                        if (current->personality & READ_IMPLIES_EXEC) {
-                               if (capabilities & BDI_CAP_EXEC_MAP)
+                               if (capabilities & NOMMU_MAP_EXEC)
                                        prot |= PROT_EXEC;
                        }
                } else if ((prot & PROT_READ) &&
                         (prot & PROT_EXEC) &&
-                        !(capabilities & BDI_CAP_EXEC_MAP)
+                        !(capabilities & NOMMU_MAP_EXEC)
                         ) {
                        /* backing file is not executable, try to copy */
-                       capabilities &= ~BDI_CAP_MAP_DIRECT;
+                       capabilities &= ~NOMMU_MAP_DIRECT;
                }
        } else {
                /* anonymous mappings are always memory backed and can be
                 * privately mapped
                 */
-               capabilities = BDI_CAP_MAP_COPY;
+               capabilities = NOMMU_MAP_COPY;
 
                /* handle PROT_EXEC implication by PROT_READ */
                if ((prot & PROT_READ) &&
@@ -1096,7 +1120,7 @@ static unsigned long determine_vm_flags(struct file *file,
        vm_flags = calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags);
        /* vm_flags |= mm->def_flags; */
 
-       if (!(capabilities & BDI_CAP_MAP_DIRECT)) {
+       if (!(capabilities & NOMMU_MAP_DIRECT)) {
                /* attempt to share read-only copies of mapped file chunks */
                vm_flags |= VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
                if (file && !(prot & PROT_WRITE))
@@ -1105,7 +1129,7 @@ static unsigned long determine_vm_flags(struct file *file,
                /* overlay a shareable mapping on the backing device or inode
                 * if possible - used for chardevs, ramfs/tmpfs/shmfs and
                 * romfs/cramfs */
-               vm_flags |= VM_MAYSHARE | (capabilities & BDI_CAP_VMFLAGS);
+               vm_flags |= VM_MAYSHARE | (capabilities & NOMMU_VMFLAGS);
                if (flags & MAP_SHARED)
                        vm_flags |= VM_SHARED;
        }
@@ -1158,7 +1182,7 @@ static int do_mmap_private(struct vm_area_struct *vma,
         * shared mappings on devices or memory
         * - VM_MAYSHARE will be set if it may attempt to share
         */
-       if (capabilities & BDI_CAP_MAP_DIRECT) {
+       if (capabilities & NOMMU_MAP_DIRECT) {
                ret = vma->vm_file->f_op->mmap(vma->vm_file, vma);
                if (ret == 0) {
                        /* shouldn't return success if we're not sharing */
@@ -1347,7 +1371,7 @@ unsigned long do_mmap_pgoff(struct file *file,
                        if ((pregion->vm_pgoff != pgoff || rpglen != pglen) &&
                            !(pgoff >= pregion->vm_pgoff && pgend <= rpgend)) {
                                /* new mapping is not a subset of the region */
-                               if (!(capabilities & BDI_CAP_MAP_DIRECT))
+                               if (!(capabilities & NOMMU_MAP_DIRECT))
                                        goto sharing_violation;
                                continue;
                        }
@@ -1386,7 +1410,7 @@ unsigned long do_mmap_pgoff(struct file *file,
                 * - this is the hook for quasi-memory character devices to
                 *   tell us the location of a shared mapping
                 */
-               if (capabilities & BDI_CAP_MAP_DIRECT) {
+               if (capabilities & NOMMU_MAP_DIRECT) {
                        addr = file->f_op->get_unmapped_area(file, addr, len,
                                                             pgoff, flags);
                        if (IS_ERR_VALUE(addr)) {
@@ -1398,10 +1422,10 @@ unsigned long do_mmap_pgoff(struct file *file,
                                 * the mapping so we'll have to attempt to copy
                                 * it */
                                ret = -ENODEV;
-                               if (!(capabilities & BDI_CAP_MAP_COPY))
+                               if (!(capabilities & NOMMU_MAP_COPY))
                                        goto error_just_free;
 
-                               capabilities &= ~BDI_CAP_MAP_DIRECT;
+                               capabilities &= ~NOMMU_MAP_DIRECT;
                        } else {
                                vma->vm_start = region->vm_start = addr;
                                vma->vm_end = region->vm_end = addr + len;
@@ -1412,7 +1436,7 @@ unsigned long do_mmap_pgoff(struct file *file,
        vma->vm_region = region;
 
        /* set up the mapping
-        * - the region is filled in if BDI_CAP_MAP_DIRECT is still set
+        * - the region is filled in if NOMMU_MAP_DIRECT is still set
         */
        if (file && vma->vm_flags & VM_SHARED)
                ret = do_mmap_shared_file(vma);
@@ -1895,7 +1919,7 @@ EXPORT_SYMBOL(unmap_mapping_range);
  */
 int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
 {
-       unsigned long free, allowed, reserve;
+       long free, allowed, reserve;
 
        vm_acct_memory(pages);
 
@@ -1959,7 +1983,7 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
         */
        if (mm) {
                reserve = sysctl_user_reserve_kbytes >> (PAGE_SHIFT - 10);
-               allowed -= min(mm->total_vm / 32, reserve);
+               allowed -= min_t(long, mm->total_vm / 32, reserve);
        }
 
        if (percpu_counter_read_positive(&vm_committed_as) < allowed)