2 * hugetlbpage-backed filesystem. Based on ramfs.
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/quotaops.h>
30 #include <linux/slab.h>
31 #include <linux/dnotify.h>
32 #include <linux/statfs.h>
33 #include <linux/security.h>
35 #include <asm/uaccess.h>
37 /* some random number */
38 #define HUGETLBFS_MAGIC 0x958458f6
40 static const struct super_operations hugetlbfs_ops;
41 static const struct address_space_operations hugetlbfs_aops;
42 const struct file_operations hugetlbfs_file_operations;
43 static const struct inode_operations hugetlbfs_dir_inode_operations;
44 static const struct inode_operations hugetlbfs_inode_operations;
46 static struct backing_dev_info hugetlbfs_backing_dev_info = {
47 .ra_pages = 0, /* No readahead */
48 .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK,
51 int sysctl_hugetlb_shm_group;
54 Opt_size, Opt_nr_inodes,
55 Opt_mode, Opt_uid, Opt_gid,
59 static match_table_t tokens = {
60 {Opt_size, "size=%s"},
61 {Opt_nr_inodes, "nr_inodes=%s"},
62 {Opt_mode, "mode=%o"},
68 static void huge_pagevec_release(struct pagevec *pvec)
72 for (i = 0; i < pagevec_count(pvec); ++i)
73 put_page(pvec->pages[i]);
78 static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma)
80 struct inode *inode = file->f_path.dentry->d_inode;
83 struct hstate *h = hstate_file(file);
86 * vma address alignment (but not the pgoff alignment) has
87 * already been checked by prepare_hugepage_range. If you add
88 * any error returns here, do so after setting VM_HUGETLB, so
89 * is_vm_hugetlb_page tests below unmap_region go the right
90 * way when do_mmap_pgoff unwinds (may be important on powerpc
93 vma->vm_flags |= VM_HUGETLB | VM_RESERVED;
94 vma->vm_ops = &hugetlb_vm_ops;
96 if (vma->vm_pgoff & ~(huge_page_mask(h) >> PAGE_SHIFT))
99 vma_len = (loff_t)(vma->vm_end - vma->vm_start);
101 mutex_lock(&inode->i_mutex);
105 len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
107 if (hugetlb_reserve_pages(inode,
108 vma->vm_pgoff >> huge_page_order(h),
109 len >> huge_page_shift(h), vma))
113 hugetlb_prefault_arch_hook(vma->vm_mm);
114 if (vma->vm_flags & VM_WRITE && inode->i_size < len)
117 mutex_unlock(&inode->i_mutex);
123 * Called under down_write(mmap_sem).
126 #ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
128 hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
129 unsigned long len, unsigned long pgoff, unsigned long flags)
131 struct mm_struct *mm = current->mm;
132 struct vm_area_struct *vma;
133 unsigned long start_addr;
134 struct hstate *h = hstate_file(file);
136 if (len & ~huge_page_mask(h))
141 if (flags & MAP_FIXED) {
142 if (prepare_hugepage_range(file, addr, len))
148 addr = ALIGN(addr, huge_page_size(h));
149 vma = find_vma(mm, addr);
150 if (TASK_SIZE - len >= addr &&
151 (!vma || addr + len <= vma->vm_start))
155 start_addr = mm->free_area_cache;
157 if (len <= mm->cached_hole_size)
158 start_addr = TASK_UNMAPPED_BASE;
161 addr = ALIGN(start_addr, huge_page_size(h));
163 for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
164 /* At this point: (!vma || addr < vma->vm_end). */
165 if (TASK_SIZE - len < addr) {
167 * Start a new search - just in case we missed
170 if (start_addr != TASK_UNMAPPED_BASE) {
171 start_addr = TASK_UNMAPPED_BASE;
177 if (!vma || addr + len <= vma->vm_start)
179 addr = ALIGN(vma->vm_end, huge_page_size(h));
185 hugetlbfs_read_actor(struct page *page, unsigned long offset,
186 char __user *buf, unsigned long count,
190 unsigned long left, copied = 0;
196 /* Find which 4k chunk and offset with in that chunk */
197 i = offset >> PAGE_CACHE_SHIFT;
198 offset = offset & ~PAGE_CACHE_MASK;
201 chunksize = PAGE_CACHE_SIZE;
204 if (chunksize > size)
206 kaddr = kmap(&page[i]);
207 left = __copy_to_user(buf, kaddr + offset, chunksize);
210 copied += (chunksize - left);
219 return copied ? copied : -EFAULT;
223 * Support for read() - Find the page attached to f_mapping and copy out the
224 * data. Its *very* similar to do_generic_mapping_read(), we can't use that
225 * since it has PAGE_CACHE_SIZE assumptions.
227 static ssize_t hugetlbfs_read(struct file *filp, char __user *buf,
228 size_t len, loff_t *ppos)
230 struct hstate *h = hstate_file(filp);
231 struct address_space *mapping = filp->f_mapping;
232 struct inode *inode = mapping->host;
233 unsigned long index = *ppos >> huge_page_shift(h);
234 unsigned long offset = *ppos & ~huge_page_mask(h);
235 unsigned long end_index;
239 mutex_lock(&inode->i_mutex);
241 /* validate length */
245 isize = i_size_read(inode);
249 end_index = (isize - 1) >> huge_page_shift(h);
252 unsigned long nr, ret;
254 /* nr is the maximum number of bytes to copy from this page */
255 nr = huge_page_size(h);
256 if (index >= end_index) {
257 if (index > end_index)
259 nr = ((isize - 1) & ~huge_page_mask(h)) + 1;
267 page = find_get_page(mapping, index);
268 if (unlikely(page == NULL)) {
270 * We have a HOLE, zero out the user-buffer for the
271 * length of the hole or request.
273 ret = len < nr ? len : nr;
274 if (clear_user(buf, ret))
278 * We have the page, copy it to user space buffer.
280 ret = hugetlbfs_read_actor(page, offset, buf, len, nr);
286 page_cache_release(page);
293 index += offset >> huge_page_shift(h);
294 offset &= ~huge_page_mask(h);
297 page_cache_release(page);
299 /* short read or no more work */
300 if ((ret != nr) || (len == 0))
304 *ppos = ((loff_t)index << huge_page_shift(h)) + offset;
305 mutex_unlock(&inode->i_mutex);
310 * Read a page. Again trivial. If it didn't already exist
311 * in the page cache, it is zero-filled.
313 static int hugetlbfs_readpage(struct file *file, struct page * page)
319 static int hugetlbfs_write_begin(struct file *file,
320 struct address_space *mapping,
321 loff_t pos, unsigned len, unsigned flags,
322 struct page **pagep, void **fsdata)
327 static int hugetlbfs_write_end(struct file *file, struct address_space *mapping,
328 loff_t pos, unsigned len, unsigned copied,
329 struct page *page, void *fsdata)
335 static void truncate_huge_page(struct page *page)
337 cancel_dirty_page(page, /* No IO accounting for huge pages? */0);
338 ClearPageUptodate(page);
339 remove_from_page_cache(page);
343 static void truncate_hugepages(struct inode *inode, loff_t lstart)
345 struct hstate *h = hstate_inode(inode);
346 struct address_space *mapping = &inode->i_data;
347 const pgoff_t start = lstart >> huge_page_shift(h);
352 pagevec_init(&pvec, 0);
355 if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
362 for (i = 0; i < pagevec_count(&pvec); ++i) {
363 struct page *page = pvec.pages[i];
366 if (page->index > next)
369 truncate_huge_page(page);
373 huge_pagevec_release(&pvec);
375 BUG_ON(!lstart && mapping->nrpages);
376 hugetlb_unreserve_pages(inode, start, freed);
379 static void hugetlbfs_delete_inode(struct inode *inode)
381 truncate_hugepages(inode, 0);
385 static void hugetlbfs_forget_inode(struct inode *inode) __releases(inode_lock)
387 struct super_block *sb = inode->i_sb;
389 if (!hlist_unhashed(&inode->i_hash)) {
390 if (!(inode->i_state & (I_DIRTY|I_SYNC)))
391 list_move(&inode->i_list, &inode_unused);
392 inodes_stat.nr_unused++;
393 if (!sb || (sb->s_flags & MS_ACTIVE)) {
394 spin_unlock(&inode_lock);
397 inode->i_state |= I_WILL_FREE;
398 spin_unlock(&inode_lock);
400 * write_inode_now is a noop as we set BDI_CAP_NO_WRITEBACK
401 * in our backing_dev_info.
403 write_inode_now(inode, 1);
404 spin_lock(&inode_lock);
405 inode->i_state &= ~I_WILL_FREE;
406 inodes_stat.nr_unused--;
407 hlist_del_init(&inode->i_hash);
409 list_del_init(&inode->i_list);
410 list_del_init(&inode->i_sb_list);
411 inode->i_state |= I_FREEING;
412 inodes_stat.nr_inodes--;
413 spin_unlock(&inode_lock);
414 truncate_hugepages(inode, 0);
416 destroy_inode(inode);
419 static void hugetlbfs_drop_inode(struct inode *inode)
422 generic_delete_inode(inode);
424 hugetlbfs_forget_inode(inode);
428 hugetlb_vmtruncate_list(struct prio_tree_root *root, pgoff_t pgoff)
430 struct vm_area_struct *vma;
431 struct prio_tree_iter iter;
433 vma_prio_tree_foreach(vma, &iter, root, pgoff, ULONG_MAX) {
434 unsigned long v_offset;
437 * Can the expression below overflow on 32-bit arches?
438 * No, because the prio_tree returns us only those vmas
439 * which overlap the truncated area starting at pgoff,
440 * and no vma on a 32-bit arch can span beyond the 4GB.
442 if (vma->vm_pgoff < pgoff)
443 v_offset = (pgoff - vma->vm_pgoff) << PAGE_SHIFT;
447 __unmap_hugepage_range(vma,
448 vma->vm_start + v_offset, vma->vm_end, NULL);
452 static int hugetlb_vmtruncate(struct inode *inode, loff_t offset)
455 struct address_space *mapping = inode->i_mapping;
456 struct hstate *h = hstate_inode(inode);
458 BUG_ON(offset & ~huge_page_mask(h));
459 pgoff = offset >> PAGE_SHIFT;
461 i_size_write(inode, offset);
462 spin_lock(&mapping->i_mmap_lock);
463 if (!prio_tree_empty(&mapping->i_mmap))
464 hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff);
465 spin_unlock(&mapping->i_mmap_lock);
466 truncate_hugepages(inode, offset);
470 static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr)
472 struct inode *inode = dentry->d_inode;
473 struct hstate *h = hstate_inode(inode);
475 unsigned int ia_valid = attr->ia_valid;
479 error = inode_change_ok(inode, attr);
483 if (ia_valid & ATTR_SIZE) {
485 if (!(attr->ia_size & ~huge_page_mask(h)))
486 error = hugetlb_vmtruncate(inode, attr->ia_size);
489 attr->ia_valid &= ~ATTR_SIZE;
491 error = inode_setattr(inode, attr);
496 static struct inode *hugetlbfs_get_inode(struct super_block *sb, uid_t uid,
497 gid_t gid, int mode, dev_t dev)
501 inode = new_inode(sb);
503 struct hugetlbfs_inode_info *info;
504 inode->i_mode = mode;
508 inode->i_mapping->a_ops = &hugetlbfs_aops;
509 inode->i_mapping->backing_dev_info =&hugetlbfs_backing_dev_info;
510 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
511 INIT_LIST_HEAD(&inode->i_mapping->private_list);
512 info = HUGETLBFS_I(inode);
513 mpol_shared_policy_init(&info->policy, NULL);
514 switch (mode & S_IFMT) {
516 init_special_inode(inode, mode, dev);
519 inode->i_op = &hugetlbfs_inode_operations;
520 inode->i_fop = &hugetlbfs_file_operations;
523 inode->i_op = &hugetlbfs_dir_inode_operations;
524 inode->i_fop = &simple_dir_operations;
526 /* directory inodes start off with i_nlink == 2 (for "." entry) */
530 inode->i_op = &page_symlink_inode_operations;
538 * File creation. Allocate an inode, and we're done..
540 static int hugetlbfs_mknod(struct inode *dir,
541 struct dentry *dentry, int mode, dev_t dev)
547 if (dir->i_mode & S_ISGID) {
552 gid = current->fsgid;
554 inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, gid, mode, dev);
556 dir->i_ctime = dir->i_mtime = CURRENT_TIME;
557 d_instantiate(dentry, inode);
558 dget(dentry); /* Extra count - pin the dentry in core */
564 static int hugetlbfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
566 int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0);
572 static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd)
574 return hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0);
577 static int hugetlbfs_symlink(struct inode *dir,
578 struct dentry *dentry, const char *symname)
584 if (dir->i_mode & S_ISGID)
587 gid = current->fsgid;
589 inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid,
590 gid, S_IFLNK|S_IRWXUGO, 0);
592 int l = strlen(symname)+1;
593 error = page_symlink(inode, symname, l);
595 d_instantiate(dentry, inode);
600 dir->i_ctime = dir->i_mtime = CURRENT_TIME;
606 * mark the head page dirty
608 static int hugetlbfs_set_page_dirty(struct page *page)
610 struct page *head = compound_head(page);
616 static int hugetlbfs_statfs(struct dentry *dentry, struct kstatfs *buf)
618 struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(dentry->d_sb);
619 struct hstate *h = hstate_inode(dentry->d_inode);
621 buf->f_type = HUGETLBFS_MAGIC;
622 buf->f_bsize = huge_page_size(h);
624 spin_lock(&sbinfo->stat_lock);
625 /* If no limits set, just report 0 for max/free/used
626 * blocks, like simple_statfs() */
627 if (sbinfo->max_blocks >= 0) {
628 buf->f_blocks = sbinfo->max_blocks;
629 buf->f_bavail = buf->f_bfree = sbinfo->free_blocks;
630 buf->f_files = sbinfo->max_inodes;
631 buf->f_ffree = sbinfo->free_inodes;
633 spin_unlock(&sbinfo->stat_lock);
635 buf->f_namelen = NAME_MAX;
639 static void hugetlbfs_put_super(struct super_block *sb)
641 struct hugetlbfs_sb_info *sbi = HUGETLBFS_SB(sb);
644 sb->s_fs_info = NULL;
649 static inline int hugetlbfs_dec_free_inodes(struct hugetlbfs_sb_info *sbinfo)
651 if (sbinfo->free_inodes >= 0) {
652 spin_lock(&sbinfo->stat_lock);
653 if (unlikely(!sbinfo->free_inodes)) {
654 spin_unlock(&sbinfo->stat_lock);
657 sbinfo->free_inodes--;
658 spin_unlock(&sbinfo->stat_lock);
664 static void hugetlbfs_inc_free_inodes(struct hugetlbfs_sb_info *sbinfo)
666 if (sbinfo->free_inodes >= 0) {
667 spin_lock(&sbinfo->stat_lock);
668 sbinfo->free_inodes++;
669 spin_unlock(&sbinfo->stat_lock);
674 static struct kmem_cache *hugetlbfs_inode_cachep;
676 static struct inode *hugetlbfs_alloc_inode(struct super_block *sb)
678 struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb);
679 struct hugetlbfs_inode_info *p;
681 if (unlikely(!hugetlbfs_dec_free_inodes(sbinfo)))
683 p = kmem_cache_alloc(hugetlbfs_inode_cachep, GFP_KERNEL);
685 hugetlbfs_inc_free_inodes(sbinfo);
688 return &p->vfs_inode;
691 static void hugetlbfs_destroy_inode(struct inode *inode)
693 hugetlbfs_inc_free_inodes(HUGETLBFS_SB(inode->i_sb));
694 mpol_free_shared_policy(&HUGETLBFS_I(inode)->policy);
695 kmem_cache_free(hugetlbfs_inode_cachep, HUGETLBFS_I(inode));
698 static const struct address_space_operations hugetlbfs_aops = {
699 .readpage = hugetlbfs_readpage,
700 .write_begin = hugetlbfs_write_begin,
701 .write_end = hugetlbfs_write_end,
702 .set_page_dirty = hugetlbfs_set_page_dirty,
706 static void init_once(struct kmem_cache *cachep, void *foo)
708 struct hugetlbfs_inode_info *ei = (struct hugetlbfs_inode_info *)foo;
710 inode_init_once(&ei->vfs_inode);
713 const struct file_operations hugetlbfs_file_operations = {
714 .read = hugetlbfs_read,
715 .mmap = hugetlbfs_file_mmap,
716 .fsync = simple_sync_file,
717 .get_unmapped_area = hugetlb_get_unmapped_area,
720 static const struct inode_operations hugetlbfs_dir_inode_operations = {
721 .create = hugetlbfs_create,
722 .lookup = simple_lookup,
724 .unlink = simple_unlink,
725 .symlink = hugetlbfs_symlink,
726 .mkdir = hugetlbfs_mkdir,
727 .rmdir = simple_rmdir,
728 .mknod = hugetlbfs_mknod,
729 .rename = simple_rename,
730 .setattr = hugetlbfs_setattr,
733 static const struct inode_operations hugetlbfs_inode_operations = {
734 .setattr = hugetlbfs_setattr,
737 static const struct super_operations hugetlbfs_ops = {
738 .alloc_inode = hugetlbfs_alloc_inode,
739 .destroy_inode = hugetlbfs_destroy_inode,
740 .statfs = hugetlbfs_statfs,
741 .delete_inode = hugetlbfs_delete_inode,
742 .drop_inode = hugetlbfs_drop_inode,
743 .put_super = hugetlbfs_put_super,
744 .show_options = generic_show_options,
748 hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig)
751 substring_t args[MAX_OPT_ARGS];
757 while ((p = strsep(&options, ",")) != NULL) {
762 token = match_token(p, tokens, args);
765 if (match_int(&args[0], &option))
767 pconfig->uid = option;
771 if (match_int(&args[0], &option))
773 pconfig->gid = option;
777 if (match_octal(&args[0], &option))
779 pconfig->mode = option & 01777U;
783 unsigned long long size;
784 /* memparse() will accept a K/M/G without a digit */
785 if (!isdigit(*args[0].from))
787 size = memparse(args[0].from, &rest);
789 size <<= HPAGE_SHIFT;
790 size *= max_huge_pages;
793 pconfig->nr_blocks = (size >> HPAGE_SHIFT);
798 /* memparse() will accept a K/M/G without a digit */
799 if (!isdigit(*args[0].from))
801 pconfig->nr_inodes = memparse(args[0].from, &rest);
805 printk(KERN_ERR "hugetlbfs: Bad mount option: \"%s\"\n",
814 printk(KERN_ERR "hugetlbfs: Bad value '%s' for mount option '%s'\n",
820 hugetlbfs_fill_super(struct super_block *sb, void *data, int silent)
822 struct inode * inode;
823 struct dentry * root;
825 struct hugetlbfs_config config;
826 struct hugetlbfs_sb_info *sbinfo;
828 save_mount_options(sb, data);
830 config.nr_blocks = -1; /* No limit on size by default */
831 config.nr_inodes = -1; /* No limit on number of inodes by default */
832 config.uid = current->fsuid;
833 config.gid = current->fsgid;
835 ret = hugetlbfs_parse_options(data, &config);
839 sbinfo = kmalloc(sizeof(struct hugetlbfs_sb_info), GFP_KERNEL);
842 sb->s_fs_info = sbinfo;
843 spin_lock_init(&sbinfo->stat_lock);
844 sbinfo->max_blocks = config.nr_blocks;
845 sbinfo->free_blocks = config.nr_blocks;
846 sbinfo->max_inodes = config.nr_inodes;
847 sbinfo->free_inodes = config.nr_inodes;
848 sb->s_maxbytes = MAX_LFS_FILESIZE;
849 sb->s_blocksize = HPAGE_SIZE;
850 sb->s_blocksize_bits = HPAGE_SHIFT;
851 sb->s_magic = HUGETLBFS_MAGIC;
852 sb->s_op = &hugetlbfs_ops;
854 inode = hugetlbfs_get_inode(sb, config.uid, config.gid,
855 S_IFDIR | config.mode, 0);
859 root = d_alloc_root(inode);
871 int hugetlb_get_quota(struct address_space *mapping, long delta)
874 struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb);
876 if (sbinfo->free_blocks > -1) {
877 spin_lock(&sbinfo->stat_lock);
878 if (sbinfo->free_blocks - delta >= 0)
879 sbinfo->free_blocks -= delta;
882 spin_unlock(&sbinfo->stat_lock);
888 void hugetlb_put_quota(struct address_space *mapping, long delta)
890 struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb);
892 if (sbinfo->free_blocks > -1) {
893 spin_lock(&sbinfo->stat_lock);
894 sbinfo->free_blocks += delta;
895 spin_unlock(&sbinfo->stat_lock);
899 static int hugetlbfs_get_sb(struct file_system_type *fs_type,
900 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
902 return get_sb_nodev(fs_type, flags, data, hugetlbfs_fill_super, mnt);
905 static struct file_system_type hugetlbfs_fs_type = {
907 .get_sb = hugetlbfs_get_sb,
908 .kill_sb = kill_litter_super,
911 static struct vfsmount *hugetlbfs_vfsmount;
913 static int can_do_hugetlb_shm(void)
915 return likely(capable(CAP_IPC_LOCK) ||
916 in_group_p(sysctl_hugetlb_shm_group) ||
920 struct file *hugetlb_file_setup(const char *name, size_t size)
925 struct dentry *dentry, *root;
926 struct qstr quick_string;
928 if (!hugetlbfs_vfsmount)
929 return ERR_PTR(-ENOENT);
931 if (!can_do_hugetlb_shm())
932 return ERR_PTR(-EPERM);
934 if (!user_shm_lock(size, current->user))
935 return ERR_PTR(-ENOMEM);
937 root = hugetlbfs_vfsmount->mnt_root;
938 quick_string.name = name;
939 quick_string.len = strlen(quick_string.name);
940 quick_string.hash = 0;
941 dentry = d_alloc(root, &quick_string);
946 inode = hugetlbfs_get_inode(root->d_sb, current->fsuid,
947 current->fsgid, S_IFREG | S_IRWXUGO, 0);
952 if (hugetlb_reserve_pages(inode, 0,
953 size >> huge_page_shift(hstate_inode(inode)), NULL))
956 d_instantiate(dentry, inode);
957 inode->i_size = size;
961 file = alloc_file(hugetlbfs_vfsmount, dentry,
962 FMODE_WRITE | FMODE_READ,
963 &hugetlbfs_file_operations);
965 goto out_dentry; /* inode is already attached */
974 user_shm_unlock(size, current->user);
975 return ERR_PTR(error);
978 static int __init init_hugetlbfs_fs(void)
981 struct vfsmount *vfsmount;
983 error = bdi_init(&hugetlbfs_backing_dev_info);
987 hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache",
988 sizeof(struct hugetlbfs_inode_info),
990 if (hugetlbfs_inode_cachep == NULL)
993 error = register_filesystem(&hugetlbfs_fs_type);
997 vfsmount = kern_mount(&hugetlbfs_fs_type);
999 if (!IS_ERR(vfsmount)) {
1000 hugetlbfs_vfsmount = vfsmount;
1004 error = PTR_ERR(vfsmount);
1008 kmem_cache_destroy(hugetlbfs_inode_cachep);
1010 bdi_destroy(&hugetlbfs_backing_dev_info);
1014 static void __exit exit_hugetlbfs_fs(void)
1016 kmem_cache_destroy(hugetlbfs_inode_cachep);
1017 unregister_filesystem(&hugetlbfs_fs_type);
1018 bdi_destroy(&hugetlbfs_backing_dev_info);
1021 module_init(init_hugetlbfs_fs)
1022 module_exit(exit_hugetlbfs_fs)
1024 MODULE_LICENSE("GPL");