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 truncate_hugepages(inode
, 0);
374 hugetlb_vmtruncate_list(struct rb_root
*root
, pgoff_t pgoff
)
376 struct vm_area_struct
*vma
;
378 vma_interval_tree_foreach(vma
, root
, pgoff
, ULONG_MAX
) {
379 unsigned long v_offset
;
382 * Can the expression below overflow on 32-bit arches?
383 * No, because the interval tree returns us only those vmas
384 * which overlap the truncated area starting at pgoff,
385 * and no vma on a 32-bit arch can span beyond the 4GB.
387 if (vma
->vm_pgoff
< pgoff
)
388 v_offset
= (pgoff
- vma
->vm_pgoff
) << PAGE_SHIFT
;
392 unmap_hugepage_range(vma
, vma
->vm_start
+ v_offset
,
397 static int hugetlb_vmtruncate(struct inode
*inode
, loff_t offset
)
400 struct address_space
*mapping
= inode
->i_mapping
;
401 struct hstate
*h
= hstate_inode(inode
);
403 BUG_ON(offset
& ~huge_page_mask(h
));
404 pgoff
= offset
>> PAGE_SHIFT
;
406 i_size_write(inode
, offset
);
407 mutex_lock(&mapping
->i_mmap_mutex
);
408 if (!RB_EMPTY_ROOT(&mapping
->i_mmap
))
409 hugetlb_vmtruncate_list(&mapping
->i_mmap
, pgoff
);
410 mutex_unlock(&mapping
->i_mmap_mutex
);
411 truncate_hugepages(inode
, offset
);
415 static int hugetlbfs_setattr(struct dentry
*dentry
, struct iattr
*attr
)
417 struct inode
*inode
= dentry
->d_inode
;
418 struct hstate
*h
= hstate_inode(inode
);
420 unsigned int ia_valid
= attr
->ia_valid
;
424 error
= inode_change_ok(inode
, attr
);
428 if (ia_valid
& ATTR_SIZE
) {
430 if (attr
->ia_size
& ~huge_page_mask(h
))
432 error
= hugetlb_vmtruncate(inode
, attr
->ia_size
);
437 setattr_copy(inode
, attr
);
438 mark_inode_dirty(inode
);
442 static struct inode
*hugetlbfs_get_root(struct super_block
*sb
,
443 struct hugetlbfs_config
*config
)
447 inode
= new_inode(sb
);
449 struct hugetlbfs_inode_info
*info
;
450 inode
->i_ino
= get_next_ino();
451 inode
->i_mode
= S_IFDIR
| config
->mode
;
452 inode
->i_uid
= config
->uid
;
453 inode
->i_gid
= config
->gid
;
454 inode
->i_atime
= inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
455 info
= HUGETLBFS_I(inode
);
456 mpol_shared_policy_init(&info
->policy
, NULL
);
457 inode
->i_op
= &hugetlbfs_dir_inode_operations
;
458 inode
->i_fop
= &simple_dir_operations
;
459 /* directory inodes start off with i_nlink == 2 (for "." entry) */
461 lockdep_annotate_inode_mutex_key(inode
);
467 * Hugetlbfs is not reclaimable; therefore its i_mmap_mutex will never
468 * be taken from reclaim -- unlike regular filesystems. This needs an
469 * annotation because huge_pmd_share() does an allocation under
472 struct lock_class_key hugetlbfs_i_mmap_mutex_key
;
474 static struct inode
*hugetlbfs_get_inode(struct super_block
*sb
,
476 umode_t mode
, dev_t dev
)
480 inode
= new_inode(sb
);
482 struct hugetlbfs_inode_info
*info
;
483 inode
->i_ino
= get_next_ino();
484 inode_init_owner(inode
, dir
, mode
);
485 lockdep_set_class(&inode
->i_mapping
->i_mmap_mutex
,
486 &hugetlbfs_i_mmap_mutex_key
);
487 inode
->i_mapping
->a_ops
= &hugetlbfs_aops
;
488 inode
->i_mapping
->backing_dev_info
=&hugetlbfs_backing_dev_info
;
489 inode
->i_atime
= inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
490 INIT_LIST_HEAD(&inode
->i_mapping
->private_list
);
491 info
= HUGETLBFS_I(inode
);
493 * The policy is initialized here even if we are creating a
494 * private inode because initialization simply creates an
495 * an empty rb tree and calls spin_lock_init(), later when we
496 * call mpol_free_shared_policy() it will just return because
497 * the rb tree will still be empty.
499 mpol_shared_policy_init(&info
->policy
, NULL
);
500 switch (mode
& S_IFMT
) {
502 init_special_inode(inode
, mode
, dev
);
505 inode
->i_op
= &hugetlbfs_inode_operations
;
506 inode
->i_fop
= &hugetlbfs_file_operations
;
509 inode
->i_op
= &hugetlbfs_dir_inode_operations
;
510 inode
->i_fop
= &simple_dir_operations
;
512 /* directory inodes start off with i_nlink == 2 (for "." entry) */
516 inode
->i_op
= &page_symlink_inode_operations
;
519 lockdep_annotate_inode_mutex_key(inode
);
525 * File creation. Allocate an inode, and we're done..
527 static int hugetlbfs_mknod(struct inode
*dir
,
528 struct dentry
*dentry
, umode_t mode
, dev_t dev
)
533 inode
= hugetlbfs_get_inode(dir
->i_sb
, dir
, mode
, dev
);
535 dir
->i_ctime
= dir
->i_mtime
= CURRENT_TIME
;
536 d_instantiate(dentry
, inode
);
537 dget(dentry
); /* Extra count - pin the dentry in core */
543 static int hugetlbfs_mkdir(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
545 int retval
= hugetlbfs_mknod(dir
, dentry
, mode
| S_IFDIR
, 0);
551 static int hugetlbfs_create(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
, bool excl
)
553 return hugetlbfs_mknod(dir
, dentry
, mode
| S_IFREG
, 0);
556 static int hugetlbfs_symlink(struct inode
*dir
,
557 struct dentry
*dentry
, const char *symname
)
562 inode
= hugetlbfs_get_inode(dir
->i_sb
, dir
, S_IFLNK
|S_IRWXUGO
, 0);
564 int l
= strlen(symname
)+1;
565 error
= page_symlink(inode
, symname
, l
);
567 d_instantiate(dentry
, inode
);
572 dir
->i_ctime
= dir
->i_mtime
= CURRENT_TIME
;
578 * mark the head page dirty
580 static int hugetlbfs_set_page_dirty(struct page
*page
)
582 struct page
*head
= compound_head(page
);
588 static int hugetlbfs_migrate_page(struct address_space
*mapping
,
589 struct page
*newpage
, struct page
*page
,
590 enum migrate_mode mode
)
594 rc
= migrate_huge_page_move_mapping(mapping
, newpage
, page
);
595 if (rc
!= MIGRATEPAGE_SUCCESS
)
597 migrate_page_copy(newpage
, page
);
599 return MIGRATEPAGE_SUCCESS
;
602 static int hugetlbfs_statfs(struct dentry
*dentry
, struct kstatfs
*buf
)
604 struct hugetlbfs_sb_info
*sbinfo
= HUGETLBFS_SB(dentry
->d_sb
);
605 struct hstate
*h
= hstate_inode(dentry
->d_inode
);
607 buf
->f_type
= HUGETLBFS_MAGIC
;
608 buf
->f_bsize
= huge_page_size(h
);
610 spin_lock(&sbinfo
->stat_lock
);
611 /* If no limits set, just report 0 for max/free/used
612 * blocks, like simple_statfs() */
616 spin_lock(&sbinfo
->spool
->lock
);
617 buf
->f_blocks
= sbinfo
->spool
->max_hpages
;
618 free_pages
= sbinfo
->spool
->max_hpages
619 - sbinfo
->spool
->used_hpages
;
620 buf
->f_bavail
= buf
->f_bfree
= free_pages
;
621 spin_unlock(&sbinfo
->spool
->lock
);
622 buf
->f_files
= sbinfo
->max_inodes
;
623 buf
->f_ffree
= sbinfo
->free_inodes
;
625 spin_unlock(&sbinfo
->stat_lock
);
627 buf
->f_namelen
= NAME_MAX
;
631 static void hugetlbfs_put_super(struct super_block
*sb
)
633 struct hugetlbfs_sb_info
*sbi
= HUGETLBFS_SB(sb
);
636 sb
->s_fs_info
= NULL
;
639 hugepage_put_subpool(sbi
->spool
);
645 static inline int hugetlbfs_dec_free_inodes(struct hugetlbfs_sb_info
*sbinfo
)
647 if (sbinfo
->free_inodes
>= 0) {
648 spin_lock(&sbinfo
->stat_lock
);
649 if (unlikely(!sbinfo
->free_inodes
)) {
650 spin_unlock(&sbinfo
->stat_lock
);
653 sbinfo
->free_inodes
--;
654 spin_unlock(&sbinfo
->stat_lock
);
660 static void hugetlbfs_inc_free_inodes(struct hugetlbfs_sb_info
*sbinfo
)
662 if (sbinfo
->free_inodes
>= 0) {
663 spin_lock(&sbinfo
->stat_lock
);
664 sbinfo
->free_inodes
++;
665 spin_unlock(&sbinfo
->stat_lock
);
670 static struct kmem_cache
*hugetlbfs_inode_cachep
;
672 static struct inode
*hugetlbfs_alloc_inode(struct super_block
*sb
)
674 struct hugetlbfs_sb_info
*sbinfo
= HUGETLBFS_SB(sb
);
675 struct hugetlbfs_inode_info
*p
;
677 if (unlikely(!hugetlbfs_dec_free_inodes(sbinfo
)))
679 p
= kmem_cache_alloc(hugetlbfs_inode_cachep
, GFP_KERNEL
);
681 hugetlbfs_inc_free_inodes(sbinfo
);
684 return &p
->vfs_inode
;
687 static void hugetlbfs_i_callback(struct rcu_head
*head
)
689 struct inode
*inode
= container_of(head
, struct inode
, i_rcu
);
690 kmem_cache_free(hugetlbfs_inode_cachep
, HUGETLBFS_I(inode
));
693 static void hugetlbfs_destroy_inode(struct inode
*inode
)
695 hugetlbfs_inc_free_inodes(HUGETLBFS_SB(inode
->i_sb
));
696 mpol_free_shared_policy(&HUGETLBFS_I(inode
)->policy
);
697 call_rcu(&inode
->i_rcu
, hugetlbfs_i_callback
);
700 static const struct address_space_operations hugetlbfs_aops
= {
701 .write_begin
= hugetlbfs_write_begin
,
702 .write_end
= hugetlbfs_write_end
,
703 .set_page_dirty
= hugetlbfs_set_page_dirty
,
704 .migratepage
= hugetlbfs_migrate_page
,
708 static void init_once(void *foo
)
710 struct hugetlbfs_inode_info
*ei
= (struct hugetlbfs_inode_info
*)foo
;
712 inode_init_once(&ei
->vfs_inode
);
715 const struct file_operations hugetlbfs_file_operations
= {
716 .read
= hugetlbfs_read
,
717 .mmap
= hugetlbfs_file_mmap
,
719 .get_unmapped_area
= hugetlb_get_unmapped_area
,
720 .llseek
= default_llseek
,
723 static const struct inode_operations hugetlbfs_dir_inode_operations
= {
724 .create
= hugetlbfs_create
,
725 .lookup
= simple_lookup
,
727 .unlink
= simple_unlink
,
728 .symlink
= hugetlbfs_symlink
,
729 .mkdir
= hugetlbfs_mkdir
,
730 .rmdir
= simple_rmdir
,
731 .mknod
= hugetlbfs_mknod
,
732 .rename
= simple_rename
,
733 .setattr
= hugetlbfs_setattr
,
736 static const struct inode_operations hugetlbfs_inode_operations
= {
737 .setattr
= hugetlbfs_setattr
,
740 static const struct super_operations hugetlbfs_ops
= {
741 .alloc_inode
= hugetlbfs_alloc_inode
,
742 .destroy_inode
= hugetlbfs_destroy_inode
,
743 .evict_inode
= hugetlbfs_evict_inode
,
744 .statfs
= hugetlbfs_statfs
,
745 .put_super
= hugetlbfs_put_super
,
746 .show_options
= generic_show_options
,
750 hugetlbfs_parse_options(char *options
, struct hugetlbfs_config
*pconfig
)
753 substring_t args
[MAX_OPT_ARGS
];
755 unsigned long long size
= 0;
756 enum { NO_SIZE
, SIZE_STD
, SIZE_PERCENT
} setsize
= NO_SIZE
;
761 while ((p
= strsep(&options
, ",")) != NULL
) {
766 token
= match_token(p
, tokens
, args
);
769 if (match_int(&args
[0], &option
))
771 pconfig
->uid
= make_kuid(current_user_ns(), option
);
772 if (!uid_valid(pconfig
->uid
))
777 if (match_int(&args
[0], &option
))
779 pconfig
->gid
= make_kgid(current_user_ns(), option
);
780 if (!gid_valid(pconfig
->gid
))
785 if (match_octal(&args
[0], &option
))
787 pconfig
->mode
= option
& 01777U;
791 /* memparse() will accept a K/M/G without a digit */
792 if (!isdigit(*args
[0].from
))
794 size
= memparse(args
[0].from
, &rest
);
797 setsize
= SIZE_PERCENT
;
802 /* memparse() will accept a K/M/G without a digit */
803 if (!isdigit(*args
[0].from
))
805 pconfig
->nr_inodes
= memparse(args
[0].from
, &rest
);
810 ps
= memparse(args
[0].from
, &rest
);
811 pconfig
->hstate
= size_to_hstate(ps
);
812 if (!pconfig
->hstate
) {
814 "hugetlbfs: Unsupported page size %lu MB\n",
822 printk(KERN_ERR
"hugetlbfs: Bad mount option: \"%s\"\n",
829 /* Do size after hstate is set up */
830 if (setsize
> NO_SIZE
) {
831 struct hstate
*h
= pconfig
->hstate
;
832 if (setsize
== SIZE_PERCENT
) {
833 size
<<= huge_page_shift(h
);
834 size
*= h
->max_huge_pages
;
837 pconfig
->nr_blocks
= (size
>> huge_page_shift(h
));
843 printk(KERN_ERR
"hugetlbfs: Bad value '%s' for mount option '%s'\n",
849 hugetlbfs_fill_super(struct super_block
*sb
, void *data
, int silent
)
852 struct hugetlbfs_config config
;
853 struct hugetlbfs_sb_info
*sbinfo
;
855 save_mount_options(sb
, data
);
857 config
.nr_blocks
= -1; /* No limit on size by default */
858 config
.nr_inodes
= -1; /* No limit on number of inodes by default */
859 config
.uid
= current_fsuid();
860 config
.gid
= current_fsgid();
862 config
.hstate
= &default_hstate
;
863 ret
= hugetlbfs_parse_options(data
, &config
);
867 sbinfo
= kmalloc(sizeof(struct hugetlbfs_sb_info
), GFP_KERNEL
);
870 sb
->s_fs_info
= sbinfo
;
871 sbinfo
->hstate
= config
.hstate
;
872 spin_lock_init(&sbinfo
->stat_lock
);
873 sbinfo
->max_inodes
= config
.nr_inodes
;
874 sbinfo
->free_inodes
= config
.nr_inodes
;
875 sbinfo
->spool
= NULL
;
876 if (config
.nr_blocks
!= -1) {
877 sbinfo
->spool
= hugepage_new_subpool(config
.nr_blocks
);
881 sb
->s_maxbytes
= MAX_LFS_FILESIZE
;
882 sb
->s_blocksize
= huge_page_size(config
.hstate
);
883 sb
->s_blocksize_bits
= huge_page_shift(config
.hstate
);
884 sb
->s_magic
= HUGETLBFS_MAGIC
;
885 sb
->s_op
= &hugetlbfs_ops
;
887 sb
->s_root
= d_make_root(hugetlbfs_get_root(sb
, &config
));
893 kfree(sbinfo
->spool
);
898 static struct dentry
*hugetlbfs_mount(struct file_system_type
*fs_type
,
899 int flags
, const char *dev_name
, void *data
)
901 return mount_nodev(fs_type
, flags
, data
, hugetlbfs_fill_super
);
904 static struct file_system_type hugetlbfs_fs_type
= {
906 .mount
= hugetlbfs_mount
,
907 .kill_sb
= kill_litter_super
,
909 MODULE_ALIAS_FS("hugetlbfs");
911 static struct vfsmount
*hugetlbfs_vfsmount
[HUGE_MAX_HSTATE
];
913 static int can_do_hugetlb_shm(void)
916 shm_group
= make_kgid(&init_user_ns
, sysctl_hugetlb_shm_group
);
917 return capable(CAP_IPC_LOCK
) || in_group_p(shm_group
);
920 static int get_hstate_idx(int page_size_log
)
922 struct hstate
*h
= hstate_sizelog(page_size_log
);
929 static struct dentry_operations anon_ops
= {
930 .d_dname
= simple_dname
934 * Note that size should be aligned to proper hugepage size in caller side,
935 * otherwise hugetlb_reserve_pages reserves one less hugepages than intended.
937 struct file
*hugetlb_file_setup(const char *name
, size_t size
,
938 vm_flags_t acctflag
, struct user_struct
**user
,
939 int creat_flags
, int page_size_log
)
941 struct file
*file
= ERR_PTR(-ENOMEM
);
944 struct super_block
*sb
;
945 struct qstr quick_string
;
948 hstate_idx
= get_hstate_idx(page_size_log
);
950 return ERR_PTR(-ENODEV
);
953 if (!hugetlbfs_vfsmount
[hstate_idx
])
954 return ERR_PTR(-ENOENT
);
956 if (creat_flags
== HUGETLB_SHMFS_INODE
&& !can_do_hugetlb_shm()) {
957 *user
= current_user();
958 if (user_shm_lock(size
, *user
)) {
960 printk_once(KERN_WARNING
961 "%s (%d): Using mlock ulimits for SHM_HUGETLB is deprecated\n",
962 current
->comm
, current
->pid
);
963 task_unlock(current
);
966 return ERR_PTR(-EPERM
);
970 sb
= hugetlbfs_vfsmount
[hstate_idx
]->mnt_sb
;
971 quick_string
.name
= name
;
972 quick_string
.len
= strlen(quick_string
.name
);
973 quick_string
.hash
= 0;
974 path
.dentry
= d_alloc_pseudo(sb
, &quick_string
);
978 d_set_d_op(path
.dentry
, &anon_ops
);
979 path
.mnt
= mntget(hugetlbfs_vfsmount
[hstate_idx
]);
980 file
= ERR_PTR(-ENOSPC
);
981 inode
= hugetlbfs_get_inode(sb
, NULL
, S_IFREG
| S_IRWXUGO
, 0);
985 file
= ERR_PTR(-ENOMEM
);
986 if (hugetlb_reserve_pages(inode
, 0,
987 size
>> huge_page_shift(hstate_inode(inode
)), NULL
,
991 d_instantiate(path
.dentry
, inode
);
992 inode
->i_size
= size
;
995 file
= alloc_file(&path
, FMODE_WRITE
| FMODE_READ
,
996 &hugetlbfs_file_operations
);
998 goto out_dentry
; /* inode is already attached */
1008 user_shm_unlock(size
, *user
);
1014 static int __init
init_hugetlbfs_fs(void)
1020 error
= bdi_init(&hugetlbfs_backing_dev_info
);
1025 hugetlbfs_inode_cachep
= kmem_cache_create("hugetlbfs_inode_cache",
1026 sizeof(struct hugetlbfs_inode_info
),
1028 if (hugetlbfs_inode_cachep
== NULL
)
1031 error
= register_filesystem(&hugetlbfs_fs_type
);
1036 for_each_hstate(h
) {
1038 unsigned ps_kb
= 1U << (h
->order
+ PAGE_SHIFT
- 10);
1040 snprintf(buf
, sizeof(buf
), "pagesize=%uK", ps_kb
);
1041 hugetlbfs_vfsmount
[i
] = kern_mount_data(&hugetlbfs_fs_type
,
1044 if (IS_ERR(hugetlbfs_vfsmount
[i
])) {
1045 pr_err("hugetlb: Cannot mount internal hugetlbfs for "
1046 "page size %uK", ps_kb
);
1047 error
= PTR_ERR(hugetlbfs_vfsmount
[i
]);
1048 hugetlbfs_vfsmount
[i
] = NULL
;
1052 /* Non default hstates are optional */
1053 if (!IS_ERR_OR_NULL(hugetlbfs_vfsmount
[default_hstate_idx
]))
1057 kmem_cache_destroy(hugetlbfs_inode_cachep
);
1059 bdi_destroy(&hugetlbfs_backing_dev_info
);
1063 static void __exit
exit_hugetlbfs_fs(void)
1070 * Make sure all delayed rcu free inodes are flushed before we
1074 kmem_cache_destroy(hugetlbfs_inode_cachep
);
1077 kern_unmount(hugetlbfs_vfsmount
[i
++]);
1078 unregister_filesystem(&hugetlbfs_fs_type
);
1079 bdi_destroy(&hugetlbfs_backing_dev_info
);
1082 module_init(init_hugetlbfs_fs
)
1083 module_exit(exit_hugetlbfs_fs
)
1085 MODULE_LICENSE("GPL");