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");