2 * hugetlbpage-backed filesystem. Based on ramfs.
4 * Nadia Yvette Chambers, 2002
6 * Copyright (C) 2002 Linus Torvalds.
9 #include <linux/module.h>
10 #include <linux/thread_info.h>
11 #include <asm/current.h>
12 #include <linux/sched.h> /* remove ASAP */
14 #include <linux/mount.h>
15 #include <linux/file.h>
16 #include <linux/kernel.h>
17 #include <linux/writeback.h>
18 #include <linux/pagemap.h>
19 #include <linux/highmem.h>
20 #include <linux/init.h>
21 #include <linux/string.h>
22 #include <linux/capability.h>
23 #include <linux/ctype.h>
24 #include <linux/backing-dev.h>
25 #include <linux/hugetlb.h>
26 #include <linux/pagevec.h>
27 #include <linux/parser.h>
28 #include <linux/mman.h>
29 #include <linux/slab.h>
30 #include <linux/dnotify.h>
31 #include <linux/statfs.h>
32 #include <linux/security.h>
33 #include <linux/magic.h>
34 #include <linux/migrate.h>
36 #include <asm/uaccess.h>
38 static const struct super_operations hugetlbfs_ops;
39 static const struct address_space_operations hugetlbfs_aops;
40 const struct file_operations hugetlbfs_file_operations;
41 static const struct inode_operations hugetlbfs_dir_inode_operations;
42 static const struct inode_operations hugetlbfs_inode_operations;
44 struct hugetlbfs_config {
50 struct hstate *hstate;
53 struct hugetlbfs_inode_info {
54 struct shared_policy policy;
55 struct inode vfs_inode;
58 static inline struct hugetlbfs_inode_info *HUGETLBFS_I(struct inode *inode)
60 return container_of(inode, struct hugetlbfs_inode_info, vfs_inode);
63 static struct backing_dev_info hugetlbfs_backing_dev_info = {
65 .ra_pages = 0, /* No readahead */
66 .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK,
69 int sysctl_hugetlb_shm_group;
72 Opt_size, Opt_nr_inodes,
73 Opt_mode, Opt_uid, Opt_gid,
78 static const match_table_t tokens = {
79 {Opt_size, "size=%s"},
80 {Opt_nr_inodes, "nr_inodes=%s"},
81 {Opt_mode, "mode=%o"},
84 {Opt_pagesize, "pagesize=%s"},
88 static void huge_pagevec_release(struct pagevec *pvec)
92 for (i = 0; i < pagevec_count(pvec); ++i)
93 put_page(pvec->pages[i]);
98 static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma)
100 struct inode *inode = file_inode(file);
103 struct hstate *h = hstate_file(file);
106 * vma address alignment (but not the pgoff alignment) has
107 * already been checked by prepare_hugepage_range. If you add
108 * any error returns here, do so after setting VM_HUGETLB, so
109 * is_vm_hugetlb_page tests below unmap_region go the right
110 * way when do_mmap_pgoff unwinds (may be important on powerpc
113 vma->vm_flags |= VM_HUGETLB | VM_DONTEXPAND;
114 vma->vm_ops = &hugetlb_vm_ops;
116 if (vma->vm_pgoff & (~huge_page_mask(h) >> PAGE_SHIFT))
119 vma_len = (loff_t)(vma->vm_end - vma->vm_start);
121 mutex_lock(&inode->i_mutex);
125 len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
127 if (hugetlb_reserve_pages(inode,
128 vma->vm_pgoff >> huge_page_order(h),
129 len >> huge_page_shift(h), vma,
134 hugetlb_prefault_arch_hook(vma->vm_mm);
135 if (vma->vm_flags & VM_WRITE && inode->i_size < len)
138 mutex_unlock(&inode->i_mutex);
144 * Called under down_write(mmap_sem).
147 #ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
149 hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
150 unsigned long len, unsigned long pgoff, unsigned long flags)
152 struct mm_struct *mm = current->mm;
153 struct vm_area_struct *vma;
154 struct hstate *h = hstate_file(file);
155 struct vm_unmapped_area_info info;
157 if (len & ~huge_page_mask(h))
162 if (flags & MAP_FIXED) {
163 if (prepare_hugepage_range(file, addr, len))
169 addr = ALIGN(addr, huge_page_size(h));
170 vma = find_vma(mm, addr);
171 if (TASK_SIZE - len >= addr &&
172 (!vma || addr + len <= vma->vm_start))
178 info.low_limit = TASK_UNMAPPED_BASE;
179 info.high_limit = TASK_SIZE;
180 info.align_mask = PAGE_MASK & ~huge_page_mask(h);
181 info.align_offset = 0;
182 return vm_unmapped_area(&info);
187 hugetlbfs_read_actor(struct page *page, unsigned long offset,
188 char __user *buf, unsigned long count,
192 unsigned long left, copied = 0;
198 /* Find which 4k chunk and offset with in that chunk */
199 i = offset >> PAGE_CACHE_SHIFT;
200 offset = offset & ~PAGE_CACHE_MASK;
203 chunksize = PAGE_CACHE_SIZE;
206 if (chunksize > size)
208 kaddr = kmap(&page[i]);
209 left = __copy_to_user(buf, kaddr + offset, chunksize);
212 copied += (chunksize - left);
221 return copied ? copied : -EFAULT;
225 * Support for read() - Find the page attached to f_mapping and copy out the
226 * data. Its *very* similar to do_generic_mapping_read(), we can't use that
227 * since it has PAGE_CACHE_SIZE assumptions.
229 static ssize_t hugetlbfs_read(struct file *filp, char __user *buf,
230 size_t len, loff_t *ppos)
232 struct hstate *h = hstate_file(filp);
233 struct address_space *mapping = filp->f_mapping;
234 struct inode *inode = mapping->host;
235 unsigned long index = *ppos >> huge_page_shift(h);
236 unsigned long offset = *ppos & ~huge_page_mask(h);
237 unsigned long end_index;
241 /* validate length */
247 unsigned long nr, ret;
250 /* nr is the maximum number of bytes to copy from this page */
251 nr = huge_page_size(h);
252 isize = i_size_read(inode);
255 end_index = (isize - 1) >> huge_page_shift(h);
256 if (index >= end_index) {
257 if (index > end_index)
259 nr = ((isize - 1) & ~huge_page_mask(h)) + 1;
266 page = find_lock_page(mapping, index);
267 if (unlikely(page == NULL)) {
269 * We have a HOLE, zero out the user-buffer for the
270 * length of the hole or request.
272 ret = len < nr ? len : nr;
273 if (clear_user(buf, ret))
281 * We have the page, copy it to user space buffer.
283 ra = hugetlbfs_read_actor(page, offset, buf, len, nr);
285 page_cache_release(page);
296 index += offset >> huge_page_shift(h);
297 offset &= ~huge_page_mask(h);
299 /* short read or no more work */
300 if ((ret != nr) || (len == 0))
304 *ppos = ((loff_t)index << huge_page_shift(h)) + offset;
308 static int hugetlbfs_write_begin(struct file *file,
309 struct address_space *mapping,
310 loff_t pos, unsigned len, unsigned flags,
311 struct page **pagep, void **fsdata)
316 static int hugetlbfs_write_end(struct file *file, struct address_space *mapping,
317 loff_t pos, unsigned len, unsigned copied,
318 struct page *page, void *fsdata)
324 static void truncate_huge_page(struct page *page)
326 cancel_dirty_page(page, /* No IO accounting for huge pages? */0);
327 ClearPageUptodate(page);
328 delete_from_page_cache(page);
331 static void truncate_hugepages(struct inode *inode, loff_t lstart)
333 struct hstate *h = hstate_inode(inode);
334 struct address_space *mapping = &inode->i_data;
335 const pgoff_t start = lstart >> huge_page_shift(h);
340 pagevec_init(&pvec, 0);
343 if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
350 for (i = 0; i < pagevec_count(&pvec); ++i) {
351 struct page *page = pvec.pages[i];
354 if (page->index > next)
357 truncate_huge_page(page);
361 huge_pagevec_release(&pvec);
363 BUG_ON(!lstart && mapping->nrpages);
364 hugetlb_unreserve_pages(inode, start, freed);
367 static void hugetlbfs_evict_inode(struct inode *inode)
369 struct resv_map *resv_map;
371 truncate_hugepages(inode, 0);
372 resv_map = (struct resv_map *)inode->i_mapping->private_data;
373 /* root inode doesn't have the resv_map, so we should check it */
375 resv_map_release(&resv_map->refs);
380 hugetlb_vmtruncate_list(struct rb_root *root, pgoff_t pgoff)
382 struct vm_area_struct *vma;
384 vma_interval_tree_foreach(vma, root, pgoff, ULONG_MAX) {
385 unsigned long v_offset;
388 * Can the expression below overflow on 32-bit arches?
389 * No, because the interval tree returns us only those vmas
390 * which overlap the truncated area starting at pgoff,
391 * and no vma on a 32-bit arch can span beyond the 4GB.
393 if (vma->vm_pgoff < pgoff)
394 v_offset = (pgoff - vma->vm_pgoff) << PAGE_SHIFT;
398 unmap_hugepage_range(vma, vma->vm_start + v_offset,
403 static int hugetlb_vmtruncate(struct inode *inode, loff_t offset)
406 struct address_space *mapping = inode->i_mapping;
407 struct hstate *h = hstate_inode(inode);
409 BUG_ON(offset & ~huge_page_mask(h));
410 pgoff = offset >> PAGE_SHIFT;
412 i_size_write(inode, offset);
413 mutex_lock(&mapping->i_mmap_mutex);
414 if (!RB_EMPTY_ROOT(&mapping->i_mmap))
415 hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff);
416 mutex_unlock(&mapping->i_mmap_mutex);
417 truncate_hugepages(inode, offset);
421 static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr)
423 struct inode *inode = dentry->d_inode;
424 struct hstate *h = hstate_inode(inode);
426 unsigned int ia_valid = attr->ia_valid;
430 error = inode_change_ok(inode, attr);
434 if (ia_valid & ATTR_SIZE) {
436 if (attr->ia_size & ~huge_page_mask(h))
438 error = hugetlb_vmtruncate(inode, attr->ia_size);
443 setattr_copy(inode, attr);
444 mark_inode_dirty(inode);
448 static struct inode *hugetlbfs_get_root(struct super_block *sb,
449 struct hugetlbfs_config *config)
453 inode = new_inode(sb);
455 struct hugetlbfs_inode_info *info;
456 inode->i_ino = get_next_ino();
457 inode->i_mode = S_IFDIR | config->mode;
458 inode->i_uid = config->uid;
459 inode->i_gid = config->gid;
460 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
461 info = HUGETLBFS_I(inode);
462 mpol_shared_policy_init(&info->policy, NULL);
463 inode->i_op = &hugetlbfs_dir_inode_operations;
464 inode->i_fop = &simple_dir_operations;
465 /* directory inodes start off with i_nlink == 2 (for "." entry) */
467 lockdep_annotate_inode_mutex_key(inode);
473 * Hugetlbfs is not reclaimable; therefore its i_mmap_mutex will never
474 * be taken from reclaim -- unlike regular filesystems. This needs an
475 * annotation because huge_pmd_share() does an allocation under
478 struct lock_class_key hugetlbfs_i_mmap_mutex_key;
480 static struct inode *hugetlbfs_get_inode(struct super_block *sb,
482 umode_t mode, dev_t dev)
485 struct resv_map *resv_map;
487 resv_map = resv_map_alloc();
491 inode = new_inode(sb);
493 struct hugetlbfs_inode_info *info;
494 inode->i_ino = get_next_ino();
495 inode_init_owner(inode, dir, mode);
496 lockdep_set_class(&inode->i_mapping->i_mmap_mutex,
497 &hugetlbfs_i_mmap_mutex_key);
498 inode->i_mapping->a_ops = &hugetlbfs_aops;
499 inode->i_mapping->backing_dev_info =&hugetlbfs_backing_dev_info;
500 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
501 inode->i_mapping->private_data = resv_map;
502 info = HUGETLBFS_I(inode);
504 * The policy is initialized here even if we are creating a
505 * private inode because initialization simply creates an
506 * an empty rb tree and calls spin_lock_init(), later when we
507 * call mpol_free_shared_policy() it will just return because
508 * the rb tree will still be empty.
510 mpol_shared_policy_init(&info->policy, NULL);
511 switch (mode & S_IFMT) {
513 init_special_inode(inode, mode, dev);
516 inode->i_op = &hugetlbfs_inode_operations;
517 inode->i_fop = &hugetlbfs_file_operations;
520 inode->i_op = &hugetlbfs_dir_inode_operations;
521 inode->i_fop = &simple_dir_operations;
523 /* directory inodes start off with i_nlink == 2 (for "." entry) */
527 inode->i_op = &page_symlink_inode_operations;
530 lockdep_annotate_inode_mutex_key(inode);
532 kref_put(&resv_map->refs, resv_map_release);
538 * File creation. Allocate an inode, and we're done..
540 static int hugetlbfs_mknod(struct inode *dir,
541 struct dentry *dentry, umode_t mode, dev_t dev)
546 inode = hugetlbfs_get_inode(dir->i_sb, dir, mode, dev);
548 dir->i_ctime = dir->i_mtime = CURRENT_TIME;
549 d_instantiate(dentry, inode);
550 dget(dentry); /* Extra count - pin the dentry in core */
556 static int hugetlbfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
558 int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0);
564 static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl)
566 return hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0);
569 static int hugetlbfs_symlink(struct inode *dir,
570 struct dentry *dentry, const char *symname)
575 inode = hugetlbfs_get_inode(dir->i_sb, dir, S_IFLNK|S_IRWXUGO, 0);
577 int l = strlen(symname)+1;
578 error = page_symlink(inode, symname, l);
580 d_instantiate(dentry, inode);
585 dir->i_ctime = dir->i_mtime = CURRENT_TIME;
591 * mark the head page dirty
593 static int hugetlbfs_set_page_dirty(struct page *page)
595 struct page *head = compound_head(page);
601 static int hugetlbfs_migrate_page(struct address_space *mapping,
602 struct page *newpage, struct page *page,
603 enum migrate_mode mode)
607 rc = migrate_huge_page_move_mapping(mapping, newpage, page);
608 if (rc != MIGRATEPAGE_SUCCESS)
610 migrate_page_copy(newpage, page);
612 return MIGRATEPAGE_SUCCESS;
615 static int hugetlbfs_statfs(struct dentry *dentry, struct kstatfs *buf)
617 struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(dentry->d_sb);
618 struct hstate *h = hstate_inode(dentry->d_inode);
620 buf->f_type = HUGETLBFS_MAGIC;
621 buf->f_bsize = huge_page_size(h);
623 spin_lock(&sbinfo->stat_lock);
624 /* If no limits set, just report 0 for max/free/used
625 * blocks, like simple_statfs() */
629 spin_lock(&sbinfo->spool->lock);
630 buf->f_blocks = sbinfo->spool->max_hpages;
631 free_pages = sbinfo->spool->max_hpages
632 - sbinfo->spool->used_hpages;
633 buf->f_bavail = buf->f_bfree = free_pages;
634 spin_unlock(&sbinfo->spool->lock);
635 buf->f_files = sbinfo->max_inodes;
636 buf->f_ffree = sbinfo->free_inodes;
638 spin_unlock(&sbinfo->stat_lock);
640 buf->f_namelen = NAME_MAX;
644 static void hugetlbfs_put_super(struct super_block *sb)
646 struct hugetlbfs_sb_info *sbi = HUGETLBFS_SB(sb);
649 sb->s_fs_info = NULL;
652 hugepage_put_subpool(sbi->spool);
658 static inline int hugetlbfs_dec_free_inodes(struct hugetlbfs_sb_info *sbinfo)
660 if (sbinfo->free_inodes >= 0) {
661 spin_lock(&sbinfo->stat_lock);
662 if (unlikely(!sbinfo->free_inodes)) {
663 spin_unlock(&sbinfo->stat_lock);
666 sbinfo->free_inodes--;
667 spin_unlock(&sbinfo->stat_lock);
673 static void hugetlbfs_inc_free_inodes(struct hugetlbfs_sb_info *sbinfo)
675 if (sbinfo->free_inodes >= 0) {
676 spin_lock(&sbinfo->stat_lock);
677 sbinfo->free_inodes++;
678 spin_unlock(&sbinfo->stat_lock);
683 static struct kmem_cache *hugetlbfs_inode_cachep;
685 static struct inode *hugetlbfs_alloc_inode(struct super_block *sb)
687 struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb);
688 struct hugetlbfs_inode_info *p;
690 if (unlikely(!hugetlbfs_dec_free_inodes(sbinfo)))
692 p = kmem_cache_alloc(hugetlbfs_inode_cachep, GFP_KERNEL);
694 hugetlbfs_inc_free_inodes(sbinfo);
697 return &p->vfs_inode;
700 static void hugetlbfs_i_callback(struct rcu_head *head)
702 struct inode *inode = container_of(head, struct inode, i_rcu);
703 kmem_cache_free(hugetlbfs_inode_cachep, HUGETLBFS_I(inode));
706 static void hugetlbfs_destroy_inode(struct inode *inode)
708 hugetlbfs_inc_free_inodes(HUGETLBFS_SB(inode->i_sb));
709 mpol_free_shared_policy(&HUGETLBFS_I(inode)->policy);
710 call_rcu(&inode->i_rcu, hugetlbfs_i_callback);
713 static const struct address_space_operations hugetlbfs_aops = {
714 .write_begin = hugetlbfs_write_begin,
715 .write_end = hugetlbfs_write_end,
716 .set_page_dirty = hugetlbfs_set_page_dirty,
717 .migratepage = hugetlbfs_migrate_page,
721 static void init_once(void *foo)
723 struct hugetlbfs_inode_info *ei = (struct hugetlbfs_inode_info *)foo;
725 inode_init_once(&ei->vfs_inode);
728 const struct file_operations hugetlbfs_file_operations = {
729 .read = hugetlbfs_read,
730 .mmap = hugetlbfs_file_mmap,
732 .get_unmapped_area = hugetlb_get_unmapped_area,
733 .llseek = default_llseek,
736 static const struct inode_operations hugetlbfs_dir_inode_operations = {
737 .create = hugetlbfs_create,
738 .lookup = simple_lookup,
740 .unlink = simple_unlink,
741 .symlink = hugetlbfs_symlink,
742 .mkdir = hugetlbfs_mkdir,
743 .rmdir = simple_rmdir,
744 .mknod = hugetlbfs_mknod,
745 .rename = simple_rename,
746 .setattr = hugetlbfs_setattr,
749 static const struct inode_operations hugetlbfs_inode_operations = {
750 .setattr = hugetlbfs_setattr,
753 static const struct super_operations hugetlbfs_ops = {
754 .alloc_inode = hugetlbfs_alloc_inode,
755 .destroy_inode = hugetlbfs_destroy_inode,
756 .evict_inode = hugetlbfs_evict_inode,
757 .statfs = hugetlbfs_statfs,
758 .put_super = hugetlbfs_put_super,
759 .show_options = generic_show_options,
763 hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig)
766 substring_t args[MAX_OPT_ARGS];
768 unsigned long long size = 0;
769 enum { NO_SIZE, SIZE_STD, SIZE_PERCENT } setsize = NO_SIZE;
774 while ((p = strsep(&options, ",")) != NULL) {
779 token = match_token(p, tokens, args);
782 if (match_int(&args[0], &option))
784 pconfig->uid = make_kuid(current_user_ns(), option);
785 if (!uid_valid(pconfig->uid))
790 if (match_int(&args[0], &option))
792 pconfig->gid = make_kgid(current_user_ns(), option);
793 if (!gid_valid(pconfig->gid))
798 if (match_octal(&args[0], &option))
800 pconfig->mode = option & 01777U;
804 /* memparse() will accept a K/M/G without a digit */
805 if (!isdigit(*args[0].from))
807 size = memparse(args[0].from, &rest);
810 setsize = SIZE_PERCENT;
815 /* memparse() will accept a K/M/G without a digit */
816 if (!isdigit(*args[0].from))
818 pconfig->nr_inodes = memparse(args[0].from, &rest);
823 ps = memparse(args[0].from, &rest);
824 pconfig->hstate = size_to_hstate(ps);
825 if (!pconfig->hstate) {
827 "hugetlbfs: Unsupported page size %lu MB\n",
835 printk(KERN_ERR "hugetlbfs: Bad mount option: \"%s\"\n",
842 /* Do size after hstate is set up */
843 if (setsize > NO_SIZE) {
844 struct hstate *h = pconfig->hstate;
845 if (setsize == SIZE_PERCENT) {
846 size <<= huge_page_shift(h);
847 size *= h->max_huge_pages;
850 pconfig->nr_blocks = (size >> huge_page_shift(h));
856 printk(KERN_ERR "hugetlbfs: Bad value '%s' for mount option '%s'\n",
862 hugetlbfs_fill_super(struct super_block *sb, void *data, int silent)
865 struct hugetlbfs_config config;
866 struct hugetlbfs_sb_info *sbinfo;
868 save_mount_options(sb, data);
870 config.nr_blocks = -1; /* No limit on size by default */
871 config.nr_inodes = -1; /* No limit on number of inodes by default */
872 config.uid = current_fsuid();
873 config.gid = current_fsgid();
875 config.hstate = &default_hstate;
876 ret = hugetlbfs_parse_options(data, &config);
880 sbinfo = kmalloc(sizeof(struct hugetlbfs_sb_info), GFP_KERNEL);
883 sb->s_fs_info = sbinfo;
884 sbinfo->hstate = config.hstate;
885 spin_lock_init(&sbinfo->stat_lock);
886 sbinfo->max_inodes = config.nr_inodes;
887 sbinfo->free_inodes = config.nr_inodes;
888 sbinfo->spool = NULL;
889 if (config.nr_blocks != -1) {
890 sbinfo->spool = hugepage_new_subpool(config.nr_blocks);
894 sb->s_maxbytes = MAX_LFS_FILESIZE;
895 sb->s_blocksize = huge_page_size(config.hstate);
896 sb->s_blocksize_bits = huge_page_shift(config.hstate);
897 sb->s_magic = HUGETLBFS_MAGIC;
898 sb->s_op = &hugetlbfs_ops;
900 sb->s_root = d_make_root(hugetlbfs_get_root(sb, &config));
906 kfree(sbinfo->spool);
911 static struct dentry *hugetlbfs_mount(struct file_system_type *fs_type,
912 int flags, const char *dev_name, void *data)
914 return mount_nodev(fs_type, flags, data, hugetlbfs_fill_super);
917 static struct file_system_type hugetlbfs_fs_type = {
919 .mount = hugetlbfs_mount,
920 .kill_sb = kill_litter_super,
922 MODULE_ALIAS_FS("hugetlbfs");
924 static struct vfsmount *hugetlbfs_vfsmount[HUGE_MAX_HSTATE];
926 static int can_do_hugetlb_shm(void)
929 shm_group = make_kgid(&init_user_ns, sysctl_hugetlb_shm_group);
930 return capable(CAP_IPC_LOCK) || in_group_p(shm_group);
933 static int get_hstate_idx(int page_size_log)
935 struct hstate *h = hstate_sizelog(page_size_log);
942 static struct dentry_operations anon_ops = {
943 .d_dname = simple_dname
947 * Note that size should be aligned to proper hugepage size in caller side,
948 * otherwise hugetlb_reserve_pages reserves one less hugepages than intended.
950 struct file *hugetlb_file_setup(const char *name, size_t size,
951 vm_flags_t acctflag, struct user_struct **user,
952 int creat_flags, int page_size_log)
954 struct file *file = ERR_PTR(-ENOMEM);
957 struct super_block *sb;
958 struct qstr quick_string;
961 hstate_idx = get_hstate_idx(page_size_log);
963 return ERR_PTR(-ENODEV);
966 if (!hugetlbfs_vfsmount[hstate_idx])
967 return ERR_PTR(-ENOENT);
969 if (creat_flags == HUGETLB_SHMFS_INODE && !can_do_hugetlb_shm()) {
970 *user = current_user();
971 if (user_shm_lock(size, *user)) {
973 printk_once(KERN_WARNING
974 "%s (%d): Using mlock ulimits for SHM_HUGETLB is deprecated\n",
975 current->comm, current->pid);
976 task_unlock(current);
979 return ERR_PTR(-EPERM);
983 sb = hugetlbfs_vfsmount[hstate_idx]->mnt_sb;
984 quick_string.name = name;
985 quick_string.len = strlen(quick_string.name);
986 quick_string.hash = 0;
987 path.dentry = d_alloc_pseudo(sb, &quick_string);
991 d_set_d_op(path.dentry, &anon_ops);
992 path.mnt = mntget(hugetlbfs_vfsmount[hstate_idx]);
993 file = ERR_PTR(-ENOSPC);
994 inode = hugetlbfs_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0);
998 file = ERR_PTR(-ENOMEM);
999 if (hugetlb_reserve_pages(inode, 0,
1000 size >> huge_page_shift(hstate_inode(inode)), NULL,
1004 d_instantiate(path.dentry, inode);
1005 inode->i_size = size;
1008 file = alloc_file(&path, FMODE_WRITE | FMODE_READ,
1009 &hugetlbfs_file_operations);
1011 goto out_dentry; /* inode is already attached */
1021 user_shm_unlock(size, *user);
1027 static int __init init_hugetlbfs_fs(void)
1033 error = bdi_init(&hugetlbfs_backing_dev_info);
1038 hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache",
1039 sizeof(struct hugetlbfs_inode_info),
1041 if (hugetlbfs_inode_cachep == NULL)
1044 error = register_filesystem(&hugetlbfs_fs_type);
1049 for_each_hstate(h) {
1051 unsigned ps_kb = 1U << (h->order + PAGE_SHIFT - 10);
1053 snprintf(buf, sizeof(buf), "pagesize=%uK", ps_kb);
1054 hugetlbfs_vfsmount[i] = kern_mount_data(&hugetlbfs_fs_type,
1057 if (IS_ERR(hugetlbfs_vfsmount[i])) {
1058 pr_err("hugetlb: Cannot mount internal hugetlbfs for "
1059 "page size %uK", ps_kb);
1060 error = PTR_ERR(hugetlbfs_vfsmount[i]);
1061 hugetlbfs_vfsmount[i] = NULL;
1065 /* Non default hstates are optional */
1066 if (!IS_ERR_OR_NULL(hugetlbfs_vfsmount[default_hstate_idx]))
1070 kmem_cache_destroy(hugetlbfs_inode_cachep);
1072 bdi_destroy(&hugetlbfs_backing_dev_info);
1076 static void __exit exit_hugetlbfs_fs(void)
1083 * Make sure all delayed rcu free inodes are flushed before we
1087 kmem_cache_destroy(hugetlbfs_inode_cachep);
1090 kern_unmount(hugetlbfs_vfsmount[i++]);
1091 unregister_filesystem(&hugetlbfs_fs_type);
1092 bdi_destroy(&hugetlbfs_backing_dev_info);
1095 module_init(init_hugetlbfs_fs)
1096 module_exit(exit_hugetlbfs_fs)
1098 MODULE_LICENSE("GPL");