Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * hugetlbpage-backed filesystem. Based on ramfs. | |
3 | * | |
4 | * William Irwin, 2002 | |
5 | * | |
6 | * Copyright (C) 2002 Linus Torvalds. | |
7 | */ | |
8 | ||
9 | #include <linux/module.h> | |
10 | #include <linux/thread_info.h> | |
11 | #include <asm/current.h> | |
12 | #include <linux/sched.h> /* remove ASAP */ | |
13 | #include <linux/fs.h> | |
14 | #include <linux/mount.h> | |
15 | #include <linux/file.h> | |
e73a75fa | 16 | #include <linux/kernel.h> |
1da177e4 LT |
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> | |
16f7e0fe | 22 | #include <linux/capability.h> |
e73a75fa | 23 | #include <linux/ctype.h> |
1da177e4 LT |
24 | #include <linux/backing-dev.h> |
25 | #include <linux/hugetlb.h> | |
26 | #include <linux/pagevec.h> | |
e73a75fa | 27 | #include <linux/parser.h> |
036e0856 | 28 | #include <linux/mman.h> |
1da177e4 LT |
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> | |
34 | ||
35 | #include <asm/uaccess.h> | |
36 | ||
37 | /* some random number */ | |
38 | #define HUGETLBFS_MAGIC 0x958458f6 | |
39 | ||
ee9b6d61 | 40 | static const struct super_operations hugetlbfs_ops; |
f5e54d6e | 41 | static const struct address_space_operations hugetlbfs_aops; |
4b6f5d20 | 42 | const struct file_operations hugetlbfs_file_operations; |
92e1d5be AV |
43 | static const struct inode_operations hugetlbfs_dir_inode_operations; |
44 | static const struct inode_operations hugetlbfs_inode_operations; | |
1da177e4 LT |
45 | |
46 | static struct backing_dev_info hugetlbfs_backing_dev_info = { | |
47 | .ra_pages = 0, /* No readahead */ | |
48 | .capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK, | |
49 | }; | |
50 | ||
51 | int sysctl_hugetlb_shm_group; | |
52 | ||
e73a75fa RD |
53 | enum { |
54 | Opt_size, Opt_nr_inodes, | |
55 | Opt_mode, Opt_uid, Opt_gid, | |
56 | Opt_err, | |
57 | }; | |
58 | ||
59 | static match_table_t tokens = { | |
60 | {Opt_size, "size=%s"}, | |
61 | {Opt_nr_inodes, "nr_inodes=%s"}, | |
62 | {Opt_mode, "mode=%o"}, | |
63 | {Opt_uid, "uid=%u"}, | |
64 | {Opt_gid, "gid=%u"}, | |
65 | {Opt_err, NULL}, | |
66 | }; | |
67 | ||
2e9b367c AL |
68 | static void huge_pagevec_release(struct pagevec *pvec) |
69 | { | |
70 | int i; | |
71 | ||
72 | for (i = 0; i < pagevec_count(pvec); ++i) | |
73 | put_page(pvec->pages[i]); | |
74 | ||
75 | pagevec_reinit(pvec); | |
76 | } | |
77 | ||
1da177e4 LT |
78 | static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma) |
79 | { | |
b39424e2 | 80 | struct inode *inode = file->f_path.dentry->d_inode; |
1da177e4 LT |
81 | loff_t len, vma_len; |
82 | int ret; | |
83 | ||
68589bc3 HD |
84 | /* |
85 | * vma alignment has already been checked by prepare_hugepage_range. | |
86 | * If you add any error returns here, do so after setting VM_HUGETLB, | |
87 | * so is_vm_hugetlb_page tests below unmap_region go the right way | |
88 | * when do_mmap_pgoff unwinds (may be important on powerpc and ia64). | |
89 | */ | |
90 | vma->vm_flags |= VM_HUGETLB | VM_RESERVED; | |
91 | vma->vm_ops = &hugetlb_vm_ops; | |
1da177e4 LT |
92 | |
93 | vma_len = (loff_t)(vma->vm_end - vma->vm_start); | |
94 | ||
1b1dcc1b | 95 | mutex_lock(&inode->i_mutex); |
1da177e4 | 96 | file_accessed(file); |
1da177e4 LT |
97 | |
98 | ret = -ENOMEM; | |
99 | len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); | |
1da177e4 | 100 | |
a43a8c39 CK |
101 | if (vma->vm_flags & VM_MAYSHARE && |
102 | hugetlb_reserve_pages(inode, vma->vm_pgoff >> (HPAGE_SHIFT-PAGE_SHIFT), | |
103 | len >> HPAGE_SHIFT)) | |
104 | goto out; | |
b45b5bd6 | 105 | |
4c887265 AL |
106 | ret = 0; |
107 | hugetlb_prefault_arch_hook(vma->vm_mm); | |
b6174df5 | 108 | if (vma->vm_flags & VM_WRITE && inode->i_size < len) |
1da177e4 LT |
109 | inode->i_size = len; |
110 | out: | |
1b1dcc1b | 111 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
112 | |
113 | return ret; | |
114 | } | |
115 | ||
116 | /* | |
508034a3 | 117 | * Called under down_write(mmap_sem). |
1da177e4 LT |
118 | */ |
119 | ||
d2ba27e8 | 120 | #ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA |
1da177e4 LT |
121 | static unsigned long |
122 | hugetlb_get_unmapped_area(struct file *file, unsigned long addr, | |
123 | unsigned long len, unsigned long pgoff, unsigned long flags) | |
124 | { | |
125 | struct mm_struct *mm = current->mm; | |
126 | struct vm_area_struct *vma; | |
127 | unsigned long start_addr; | |
128 | ||
129 | if (len & ~HPAGE_MASK) | |
130 | return -EINVAL; | |
131 | if (len > TASK_SIZE) | |
132 | return -ENOMEM; | |
133 | ||
036e0856 BH |
134 | if (flags & MAP_FIXED) { |
135 | if (prepare_hugepage_range(addr, len, pgoff)) | |
136 | return -EINVAL; | |
137 | return addr; | |
138 | } | |
139 | ||
1da177e4 LT |
140 | if (addr) { |
141 | addr = ALIGN(addr, HPAGE_SIZE); | |
142 | vma = find_vma(mm, addr); | |
143 | if (TASK_SIZE - len >= addr && | |
144 | (!vma || addr + len <= vma->vm_start)) | |
145 | return addr; | |
146 | } | |
147 | ||
148 | start_addr = mm->free_area_cache; | |
149 | ||
1363c3cd WW |
150 | if (len <= mm->cached_hole_size) |
151 | start_addr = TASK_UNMAPPED_BASE; | |
152 | ||
1da177e4 LT |
153 | full_search: |
154 | addr = ALIGN(start_addr, HPAGE_SIZE); | |
155 | ||
156 | for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { | |
157 | /* At this point: (!vma || addr < vma->vm_end). */ | |
158 | if (TASK_SIZE - len < addr) { | |
159 | /* | |
160 | * Start a new search - just in case we missed | |
161 | * some holes. | |
162 | */ | |
163 | if (start_addr != TASK_UNMAPPED_BASE) { | |
164 | start_addr = TASK_UNMAPPED_BASE; | |
165 | goto full_search; | |
166 | } | |
167 | return -ENOMEM; | |
168 | } | |
169 | ||
170 | if (!vma || addr + len <= vma->vm_start) | |
171 | return addr; | |
172 | addr = ALIGN(vma->vm_end, HPAGE_SIZE); | |
173 | } | |
174 | } | |
175 | #endif | |
176 | ||
177 | /* | |
178 | * Read a page. Again trivial. If it didn't already exist | |
179 | * in the page cache, it is zero-filled. | |
180 | */ | |
181 | static int hugetlbfs_readpage(struct file *file, struct page * page) | |
182 | { | |
183 | unlock_page(page); | |
184 | return -EINVAL; | |
185 | } | |
186 | ||
187 | static int hugetlbfs_prepare_write(struct file *file, | |
188 | struct page *page, unsigned offset, unsigned to) | |
189 | { | |
190 | return -EINVAL; | |
191 | } | |
192 | ||
193 | static int hugetlbfs_commit_write(struct file *file, | |
194 | struct page *page, unsigned offset, unsigned to) | |
195 | { | |
196 | return -EINVAL; | |
197 | } | |
198 | ||
1da177e4 LT |
199 | static void truncate_huge_page(struct page *page) |
200 | { | |
fba2591b | 201 | cancel_dirty_page(page, /* No IO accounting for huge pages? */0); |
1da177e4 LT |
202 | ClearPageUptodate(page); |
203 | remove_from_page_cache(page); | |
204 | put_page(page); | |
205 | } | |
206 | ||
b45b5bd6 | 207 | static void truncate_hugepages(struct inode *inode, loff_t lstart) |
1da177e4 | 208 | { |
b45b5bd6 | 209 | struct address_space *mapping = &inode->i_data; |
1da177e4 LT |
210 | const pgoff_t start = lstart >> HPAGE_SHIFT; |
211 | struct pagevec pvec; | |
212 | pgoff_t next; | |
a43a8c39 | 213 | int i, freed = 0; |
1da177e4 LT |
214 | |
215 | pagevec_init(&pvec, 0); | |
216 | next = start; | |
217 | while (1) { | |
218 | if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { | |
219 | if (next == start) | |
220 | break; | |
221 | next = start; | |
222 | continue; | |
223 | } | |
224 | ||
225 | for (i = 0; i < pagevec_count(&pvec); ++i) { | |
226 | struct page *page = pvec.pages[i]; | |
227 | ||
228 | lock_page(page); | |
229 | if (page->index > next) | |
230 | next = page->index; | |
231 | ++next; | |
232 | truncate_huge_page(page); | |
233 | unlock_page(page); | |
234 | hugetlb_put_quota(mapping); | |
a43a8c39 | 235 | freed++; |
1da177e4 LT |
236 | } |
237 | huge_pagevec_release(&pvec); | |
238 | } | |
239 | BUG_ON(!lstart && mapping->nrpages); | |
a43a8c39 | 240 | hugetlb_unreserve_pages(inode, start, freed); |
1da177e4 LT |
241 | } |
242 | ||
243 | static void hugetlbfs_delete_inode(struct inode *inode) | |
244 | { | |
b45b5bd6 | 245 | truncate_hugepages(inode, 0); |
149f4211 CH |
246 | clear_inode(inode); |
247 | } | |
248 | ||
ddc0a51d | 249 | static void hugetlbfs_forget_inode(struct inode *inode) __releases(inode_lock) |
1da177e4 | 250 | { |
0b1533f6 CH |
251 | struct super_block *sb = inode->i_sb; |
252 | ||
253 | if (!hlist_unhashed(&inode->i_hash)) { | |
254 | if (!(inode->i_state & (I_DIRTY|I_LOCK))) | |
255 | list_move(&inode->i_list, &inode_unused); | |
256 | inodes_stat.nr_unused++; | |
257 | if (!sb || (sb->s_flags & MS_ACTIVE)) { | |
258 | spin_unlock(&inode_lock); | |
259 | return; | |
260 | } | |
261 | inode->i_state |= I_WILL_FREE; | |
1da177e4 | 262 | spin_unlock(&inode_lock); |
0b1533f6 CH |
263 | /* |
264 | * write_inode_now is a noop as we set BDI_CAP_NO_WRITEBACK | |
265 | * in our backing_dev_info. | |
266 | */ | |
267 | write_inode_now(inode, 1); | |
268 | spin_lock(&inode_lock); | |
269 | inode->i_state &= ~I_WILL_FREE; | |
270 | inodes_stat.nr_unused--; | |
271 | hlist_del_init(&inode->i_hash); | |
1da177e4 | 272 | } |
1da177e4 LT |
273 | list_del_init(&inode->i_list); |
274 | list_del_init(&inode->i_sb_list); | |
275 | inode->i_state |= I_FREEING; | |
276 | inodes_stat.nr_inodes--; | |
277 | spin_unlock(&inode_lock); | |
b45b5bd6 | 278 | truncate_hugepages(inode, 0); |
1da177e4 LT |
279 | clear_inode(inode); |
280 | destroy_inode(inode); | |
281 | } | |
282 | ||
283 | static void hugetlbfs_drop_inode(struct inode *inode) | |
284 | { | |
285 | if (!inode->i_nlink) | |
6b09b9df | 286 | generic_delete_inode(inode); |
1da177e4 LT |
287 | else |
288 | hugetlbfs_forget_inode(inode); | |
289 | } | |
290 | ||
1da177e4 | 291 | static inline void |
856fc295 | 292 | hugetlb_vmtruncate_list(struct prio_tree_root *root, pgoff_t pgoff) |
1da177e4 LT |
293 | { |
294 | struct vm_area_struct *vma; | |
295 | struct prio_tree_iter iter; | |
296 | ||
856fc295 | 297 | vma_prio_tree_foreach(vma, &iter, root, pgoff, ULONG_MAX) { |
1da177e4 LT |
298 | unsigned long v_offset; |
299 | ||
1da177e4 | 300 | /* |
856fc295 HD |
301 | * Can the expression below overflow on 32-bit arches? |
302 | * No, because the prio_tree returns us only those vmas | |
303 | * which overlap the truncated area starting at pgoff, | |
304 | * and no vma on a 32-bit arch can span beyond the 4GB. | |
1da177e4 | 305 | */ |
856fc295 HD |
306 | if (vma->vm_pgoff < pgoff) |
307 | v_offset = (pgoff - vma->vm_pgoff) << PAGE_SHIFT; | |
308 | else | |
1da177e4 LT |
309 | v_offset = 0; |
310 | ||
502717f4 | 311 | __unmap_hugepage_range(vma, |
508034a3 | 312 | vma->vm_start + v_offset, vma->vm_end); |
1da177e4 LT |
313 | } |
314 | } | |
315 | ||
316 | /* | |
317 | * Expanding truncates are not allowed. | |
318 | */ | |
319 | static int hugetlb_vmtruncate(struct inode *inode, loff_t offset) | |
320 | { | |
856fc295 | 321 | pgoff_t pgoff; |
1da177e4 LT |
322 | struct address_space *mapping = inode->i_mapping; |
323 | ||
324 | if (offset > inode->i_size) | |
325 | return -EINVAL; | |
326 | ||
327 | BUG_ON(offset & ~HPAGE_MASK); | |
856fc295 | 328 | pgoff = offset >> PAGE_SHIFT; |
1da177e4 LT |
329 | |
330 | inode->i_size = offset; | |
331 | spin_lock(&mapping->i_mmap_lock); | |
332 | if (!prio_tree_empty(&mapping->i_mmap)) | |
333 | hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff); | |
334 | spin_unlock(&mapping->i_mmap_lock); | |
b45b5bd6 | 335 | truncate_hugepages(inode, offset); |
1da177e4 LT |
336 | return 0; |
337 | } | |
338 | ||
339 | static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr) | |
340 | { | |
341 | struct inode *inode = dentry->d_inode; | |
342 | int error; | |
343 | unsigned int ia_valid = attr->ia_valid; | |
344 | ||
345 | BUG_ON(!inode); | |
346 | ||
347 | error = inode_change_ok(inode, attr); | |
348 | if (error) | |
349 | goto out; | |
350 | ||
351 | if (ia_valid & ATTR_SIZE) { | |
352 | error = -EINVAL; | |
353 | if (!(attr->ia_size & ~HPAGE_MASK)) | |
354 | error = hugetlb_vmtruncate(inode, attr->ia_size); | |
355 | if (error) | |
356 | goto out; | |
357 | attr->ia_valid &= ~ATTR_SIZE; | |
358 | } | |
359 | error = inode_setattr(inode, attr); | |
360 | out: | |
361 | return error; | |
362 | } | |
363 | ||
364 | static struct inode *hugetlbfs_get_inode(struct super_block *sb, uid_t uid, | |
365 | gid_t gid, int mode, dev_t dev) | |
366 | { | |
367 | struct inode *inode; | |
1da177e4 LT |
368 | |
369 | inode = new_inode(sb); | |
370 | if (inode) { | |
371 | struct hugetlbfs_inode_info *info; | |
372 | inode->i_mode = mode; | |
373 | inode->i_uid = uid; | |
374 | inode->i_gid = gid; | |
1da177e4 LT |
375 | inode->i_blocks = 0; |
376 | inode->i_mapping->a_ops = &hugetlbfs_aops; | |
377 | inode->i_mapping->backing_dev_info =&hugetlbfs_backing_dev_info; | |
378 | inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; | |
a43a8c39 | 379 | INIT_LIST_HEAD(&inode->i_mapping->private_list); |
1da177e4 | 380 | info = HUGETLBFS_I(inode); |
7339ff83 | 381 | mpol_shared_policy_init(&info->policy, MPOL_DEFAULT, NULL); |
1da177e4 LT |
382 | switch (mode & S_IFMT) { |
383 | default: | |
384 | init_special_inode(inode, mode, dev); | |
385 | break; | |
386 | case S_IFREG: | |
387 | inode->i_op = &hugetlbfs_inode_operations; | |
388 | inode->i_fop = &hugetlbfs_file_operations; | |
389 | break; | |
390 | case S_IFDIR: | |
391 | inode->i_op = &hugetlbfs_dir_inode_operations; | |
392 | inode->i_fop = &simple_dir_operations; | |
393 | ||
394 | /* directory inodes start off with i_nlink == 2 (for "." entry) */ | |
d8c76e6f | 395 | inc_nlink(inode); |
1da177e4 LT |
396 | break; |
397 | case S_IFLNK: | |
398 | inode->i_op = &page_symlink_inode_operations; | |
399 | break; | |
400 | } | |
401 | } | |
402 | return inode; | |
403 | } | |
404 | ||
405 | /* | |
406 | * File creation. Allocate an inode, and we're done.. | |
407 | */ | |
408 | static int hugetlbfs_mknod(struct inode *dir, | |
409 | struct dentry *dentry, int mode, dev_t dev) | |
410 | { | |
411 | struct inode *inode; | |
412 | int error = -ENOSPC; | |
413 | gid_t gid; | |
414 | ||
415 | if (dir->i_mode & S_ISGID) { | |
416 | gid = dir->i_gid; | |
417 | if (S_ISDIR(mode)) | |
418 | mode |= S_ISGID; | |
419 | } else { | |
420 | gid = current->fsgid; | |
421 | } | |
422 | inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, gid, mode, dev); | |
423 | if (inode) { | |
424 | dir->i_ctime = dir->i_mtime = CURRENT_TIME; | |
425 | d_instantiate(dentry, inode); | |
426 | dget(dentry); /* Extra count - pin the dentry in core */ | |
427 | error = 0; | |
428 | } | |
429 | return error; | |
430 | } | |
431 | ||
432 | static int hugetlbfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) | |
433 | { | |
434 | int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0); | |
435 | if (!retval) | |
d8c76e6f | 436 | inc_nlink(dir); |
1da177e4 LT |
437 | return retval; |
438 | } | |
439 | ||
440 | static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd) | |
441 | { | |
442 | return hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0); | |
443 | } | |
444 | ||
445 | static int hugetlbfs_symlink(struct inode *dir, | |
446 | struct dentry *dentry, const char *symname) | |
447 | { | |
448 | struct inode *inode; | |
449 | int error = -ENOSPC; | |
450 | gid_t gid; | |
451 | ||
452 | if (dir->i_mode & S_ISGID) | |
453 | gid = dir->i_gid; | |
454 | else | |
455 | gid = current->fsgid; | |
456 | ||
457 | inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, | |
458 | gid, S_IFLNK|S_IRWXUGO, 0); | |
459 | if (inode) { | |
460 | int l = strlen(symname)+1; | |
461 | error = page_symlink(inode, symname, l); | |
462 | if (!error) { | |
463 | d_instantiate(dentry, inode); | |
464 | dget(dentry); | |
465 | } else | |
466 | iput(inode); | |
467 | } | |
468 | dir->i_ctime = dir->i_mtime = CURRENT_TIME; | |
469 | ||
470 | return error; | |
471 | } | |
472 | ||
473 | /* | |
6649a386 | 474 | * mark the head page dirty |
1da177e4 LT |
475 | */ |
476 | static int hugetlbfs_set_page_dirty(struct page *page) | |
477 | { | |
d85f3385 | 478 | struct page *head = compound_head(page); |
6649a386 KC |
479 | |
480 | SetPageDirty(head); | |
1da177e4 LT |
481 | return 0; |
482 | } | |
483 | ||
726c3342 | 484 | static int hugetlbfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1da177e4 | 485 | { |
726c3342 | 486 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(dentry->d_sb); |
1da177e4 LT |
487 | |
488 | buf->f_type = HUGETLBFS_MAGIC; | |
489 | buf->f_bsize = HPAGE_SIZE; | |
490 | if (sbinfo) { | |
491 | spin_lock(&sbinfo->stat_lock); | |
74a8a65c DG |
492 | /* If no limits set, just report 0 for max/free/used |
493 | * blocks, like simple_statfs() */ | |
494 | if (sbinfo->max_blocks >= 0) { | |
495 | buf->f_blocks = sbinfo->max_blocks; | |
496 | buf->f_bavail = buf->f_bfree = sbinfo->free_blocks; | |
497 | buf->f_files = sbinfo->max_inodes; | |
498 | buf->f_ffree = sbinfo->free_inodes; | |
499 | } | |
1da177e4 LT |
500 | spin_unlock(&sbinfo->stat_lock); |
501 | } | |
502 | buf->f_namelen = NAME_MAX; | |
503 | return 0; | |
504 | } | |
505 | ||
506 | static void hugetlbfs_put_super(struct super_block *sb) | |
507 | { | |
508 | struct hugetlbfs_sb_info *sbi = HUGETLBFS_SB(sb); | |
509 | ||
510 | if (sbi) { | |
511 | sb->s_fs_info = NULL; | |
512 | kfree(sbi); | |
513 | } | |
514 | } | |
515 | ||
96527980 CH |
516 | static inline int hugetlbfs_dec_free_inodes(struct hugetlbfs_sb_info *sbinfo) |
517 | { | |
518 | if (sbinfo->free_inodes >= 0) { | |
519 | spin_lock(&sbinfo->stat_lock); | |
520 | if (unlikely(!sbinfo->free_inodes)) { | |
521 | spin_unlock(&sbinfo->stat_lock); | |
522 | return 0; | |
523 | } | |
524 | sbinfo->free_inodes--; | |
525 | spin_unlock(&sbinfo->stat_lock); | |
526 | } | |
527 | ||
528 | return 1; | |
529 | } | |
530 | ||
531 | static void hugetlbfs_inc_free_inodes(struct hugetlbfs_sb_info *sbinfo) | |
532 | { | |
533 | if (sbinfo->free_inodes >= 0) { | |
534 | spin_lock(&sbinfo->stat_lock); | |
535 | sbinfo->free_inodes++; | |
536 | spin_unlock(&sbinfo->stat_lock); | |
537 | } | |
538 | } | |
539 | ||
540 | ||
e18b890b | 541 | static struct kmem_cache *hugetlbfs_inode_cachep; |
1da177e4 LT |
542 | |
543 | static struct inode *hugetlbfs_alloc_inode(struct super_block *sb) | |
544 | { | |
96527980 | 545 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb); |
1da177e4 LT |
546 | struct hugetlbfs_inode_info *p; |
547 | ||
96527980 CH |
548 | if (unlikely(!hugetlbfs_dec_free_inodes(sbinfo))) |
549 | return NULL; | |
e94b1766 | 550 | p = kmem_cache_alloc(hugetlbfs_inode_cachep, GFP_KERNEL); |
96527980 CH |
551 | if (unlikely(!p)) { |
552 | hugetlbfs_inc_free_inodes(sbinfo); | |
1da177e4 | 553 | return NULL; |
96527980 | 554 | } |
1da177e4 LT |
555 | return &p->vfs_inode; |
556 | } | |
557 | ||
1da177e4 LT |
558 | static void hugetlbfs_destroy_inode(struct inode *inode) |
559 | { | |
96527980 | 560 | hugetlbfs_inc_free_inodes(HUGETLBFS_SB(inode->i_sb)); |
1da177e4 LT |
561 | mpol_free_shared_policy(&HUGETLBFS_I(inode)->policy); |
562 | kmem_cache_free(hugetlbfs_inode_cachep, HUGETLBFS_I(inode)); | |
563 | } | |
564 | ||
f5e54d6e | 565 | static const struct address_space_operations hugetlbfs_aops = { |
1da177e4 LT |
566 | .readpage = hugetlbfs_readpage, |
567 | .prepare_write = hugetlbfs_prepare_write, | |
568 | .commit_write = hugetlbfs_commit_write, | |
569 | .set_page_dirty = hugetlbfs_set_page_dirty, | |
570 | }; | |
571 | ||
96527980 | 572 | |
e18b890b | 573 | static void init_once(void *foo, struct kmem_cache *cachep, unsigned long flags) |
96527980 CH |
574 | { |
575 | struct hugetlbfs_inode_info *ei = (struct hugetlbfs_inode_info *)foo; | |
576 | ||
a35afb83 | 577 | inode_init_once(&ei->vfs_inode); |
96527980 CH |
578 | } |
579 | ||
4b6f5d20 | 580 | const struct file_operations hugetlbfs_file_operations = { |
1da177e4 LT |
581 | .mmap = hugetlbfs_file_mmap, |
582 | .fsync = simple_sync_file, | |
583 | .get_unmapped_area = hugetlb_get_unmapped_area, | |
584 | }; | |
585 | ||
92e1d5be | 586 | static const struct inode_operations hugetlbfs_dir_inode_operations = { |
1da177e4 LT |
587 | .create = hugetlbfs_create, |
588 | .lookup = simple_lookup, | |
589 | .link = simple_link, | |
590 | .unlink = simple_unlink, | |
591 | .symlink = hugetlbfs_symlink, | |
592 | .mkdir = hugetlbfs_mkdir, | |
593 | .rmdir = simple_rmdir, | |
594 | .mknod = hugetlbfs_mknod, | |
595 | .rename = simple_rename, | |
596 | .setattr = hugetlbfs_setattr, | |
597 | }; | |
598 | ||
92e1d5be | 599 | static const struct inode_operations hugetlbfs_inode_operations = { |
1da177e4 LT |
600 | .setattr = hugetlbfs_setattr, |
601 | }; | |
602 | ||
ee9b6d61 | 603 | static const struct super_operations hugetlbfs_ops = { |
1da177e4 LT |
604 | .alloc_inode = hugetlbfs_alloc_inode, |
605 | .destroy_inode = hugetlbfs_destroy_inode, | |
606 | .statfs = hugetlbfs_statfs, | |
149f4211 | 607 | .delete_inode = hugetlbfs_delete_inode, |
1da177e4 LT |
608 | .drop_inode = hugetlbfs_drop_inode, |
609 | .put_super = hugetlbfs_put_super, | |
610 | }; | |
611 | ||
612 | static int | |
613 | hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) | |
614 | { | |
e73a75fa RD |
615 | char *p, *rest; |
616 | substring_t args[MAX_OPT_ARGS]; | |
617 | int option; | |
1da177e4 LT |
618 | |
619 | if (!options) | |
620 | return 0; | |
1da177e4 | 621 | |
e73a75fa RD |
622 | while ((p = strsep(&options, ",")) != NULL) { |
623 | int token; | |
b4c07bce LS |
624 | if (!*p) |
625 | continue; | |
e73a75fa RD |
626 | |
627 | token = match_token(p, tokens, args); | |
628 | switch (token) { | |
629 | case Opt_uid: | |
630 | if (match_int(&args[0], &option)) | |
631 | goto bad_val; | |
632 | pconfig->uid = option; | |
633 | break; | |
634 | ||
635 | case Opt_gid: | |
636 | if (match_int(&args[0], &option)) | |
637 | goto bad_val; | |
638 | pconfig->gid = option; | |
639 | break; | |
640 | ||
641 | case Opt_mode: | |
642 | if (match_octal(&args[0], &option)) | |
643 | goto bad_val; | |
644 | pconfig->mode = option & 0777U; | |
645 | break; | |
646 | ||
647 | case Opt_size: { | |
648 | unsigned long long size; | |
649 | /* memparse() will accept a K/M/G without a digit */ | |
650 | if (!isdigit(*args[0].from)) | |
651 | goto bad_val; | |
652 | size = memparse(args[0].from, &rest); | |
1da177e4 LT |
653 | if (*rest == '%') { |
654 | size <<= HPAGE_SHIFT; | |
655 | size *= max_huge_pages; | |
656 | do_div(size, 100); | |
1da177e4 | 657 | } |
1da177e4 | 658 | pconfig->nr_blocks = (size >> HPAGE_SHIFT); |
e73a75fa RD |
659 | break; |
660 | } | |
1da177e4 | 661 | |
e73a75fa RD |
662 | case Opt_nr_inodes: |
663 | /* memparse() will accept a K/M/G without a digit */ | |
664 | if (!isdigit(*args[0].from)) | |
665 | goto bad_val; | |
666 | pconfig->nr_inodes = memparse(args[0].from, &rest); | |
667 | break; | |
668 | ||
669 | default: | |
b4c07bce LS |
670 | printk(KERN_ERR "hugetlbfs: Bad mount option: \"%s\"\n", |
671 | p); | |
672 | return -EINVAL; | |
e73a75fa RD |
673 | break; |
674 | } | |
1da177e4 LT |
675 | } |
676 | return 0; | |
e73a75fa RD |
677 | |
678 | bad_val: | |
679 | printk(KERN_ERR "hugetlbfs: Bad value '%s' for mount option '%s'\n", | |
680 | args[0].from, p); | |
681 | return 1; | |
1da177e4 LT |
682 | } |
683 | ||
684 | static int | |
685 | hugetlbfs_fill_super(struct super_block *sb, void *data, int silent) | |
686 | { | |
687 | struct inode * inode; | |
688 | struct dentry * root; | |
689 | int ret; | |
690 | struct hugetlbfs_config config; | |
691 | struct hugetlbfs_sb_info *sbinfo; | |
692 | ||
693 | config.nr_blocks = -1; /* No limit on size by default */ | |
694 | config.nr_inodes = -1; /* No limit on number of inodes by default */ | |
695 | config.uid = current->fsuid; | |
696 | config.gid = current->fsgid; | |
697 | config.mode = 0755; | |
698 | ret = hugetlbfs_parse_options(data, &config); | |
1da177e4 LT |
699 | if (ret) |
700 | return ret; | |
701 | ||
702 | sbinfo = kmalloc(sizeof(struct hugetlbfs_sb_info), GFP_KERNEL); | |
703 | if (!sbinfo) | |
704 | return -ENOMEM; | |
705 | sb->s_fs_info = sbinfo; | |
706 | spin_lock_init(&sbinfo->stat_lock); | |
707 | sbinfo->max_blocks = config.nr_blocks; | |
708 | sbinfo->free_blocks = config.nr_blocks; | |
709 | sbinfo->max_inodes = config.nr_inodes; | |
710 | sbinfo->free_inodes = config.nr_inodes; | |
711 | sb->s_maxbytes = MAX_LFS_FILESIZE; | |
712 | sb->s_blocksize = HPAGE_SIZE; | |
713 | sb->s_blocksize_bits = HPAGE_SHIFT; | |
714 | sb->s_magic = HUGETLBFS_MAGIC; | |
715 | sb->s_op = &hugetlbfs_ops; | |
716 | sb->s_time_gran = 1; | |
717 | inode = hugetlbfs_get_inode(sb, config.uid, config.gid, | |
718 | S_IFDIR | config.mode, 0); | |
719 | if (!inode) | |
720 | goto out_free; | |
721 | ||
722 | root = d_alloc_root(inode); | |
723 | if (!root) { | |
724 | iput(inode); | |
725 | goto out_free; | |
726 | } | |
727 | sb->s_root = root; | |
728 | return 0; | |
729 | out_free: | |
730 | kfree(sbinfo); | |
731 | return -ENOMEM; | |
732 | } | |
733 | ||
734 | int hugetlb_get_quota(struct address_space *mapping) | |
735 | { | |
736 | int ret = 0; | |
737 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); | |
738 | ||
739 | if (sbinfo->free_blocks > -1) { | |
740 | spin_lock(&sbinfo->stat_lock); | |
741 | if (sbinfo->free_blocks > 0) | |
742 | sbinfo->free_blocks--; | |
743 | else | |
744 | ret = -ENOMEM; | |
745 | spin_unlock(&sbinfo->stat_lock); | |
746 | } | |
747 | ||
748 | return ret; | |
749 | } | |
750 | ||
751 | void hugetlb_put_quota(struct address_space *mapping) | |
752 | { | |
753 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); | |
754 | ||
755 | if (sbinfo->free_blocks > -1) { | |
756 | spin_lock(&sbinfo->stat_lock); | |
757 | sbinfo->free_blocks++; | |
758 | spin_unlock(&sbinfo->stat_lock); | |
759 | } | |
760 | } | |
761 | ||
454e2398 DH |
762 | static int hugetlbfs_get_sb(struct file_system_type *fs_type, |
763 | int flags, const char *dev_name, void *data, struct vfsmount *mnt) | |
1da177e4 | 764 | { |
454e2398 | 765 | return get_sb_nodev(fs_type, flags, data, hugetlbfs_fill_super, mnt); |
1da177e4 LT |
766 | } |
767 | ||
768 | static struct file_system_type hugetlbfs_fs_type = { | |
769 | .name = "hugetlbfs", | |
770 | .get_sb = hugetlbfs_get_sb, | |
771 | .kill_sb = kill_litter_super, | |
772 | }; | |
773 | ||
774 | static struct vfsmount *hugetlbfs_vfsmount; | |
775 | ||
1da177e4 LT |
776 | static int can_do_hugetlb_shm(void) |
777 | { | |
778 | return likely(capable(CAP_IPC_LOCK) || | |
779 | in_group_p(sysctl_hugetlb_shm_group) || | |
780 | can_do_mlock()); | |
781 | } | |
782 | ||
9d66586f | 783 | struct file *hugetlb_file_setup(const char *name, size_t size) |
1da177e4 LT |
784 | { |
785 | int error = -ENOMEM; | |
786 | struct file *file; | |
787 | struct inode *inode; | |
788 | struct dentry *dentry, *root; | |
789 | struct qstr quick_string; | |
1da177e4 | 790 | |
5bc98594 AM |
791 | if (!hugetlbfs_vfsmount) |
792 | return ERR_PTR(-ENOENT); | |
793 | ||
1da177e4 LT |
794 | if (!can_do_hugetlb_shm()) |
795 | return ERR_PTR(-EPERM); | |
796 | ||
1da177e4 LT |
797 | if (!user_shm_lock(size, current->user)) |
798 | return ERR_PTR(-ENOMEM); | |
799 | ||
800 | root = hugetlbfs_vfsmount->mnt_root; | |
9d66586f | 801 | quick_string.name = name; |
1da177e4 LT |
802 | quick_string.len = strlen(quick_string.name); |
803 | quick_string.hash = 0; | |
804 | dentry = d_alloc(root, &quick_string); | |
805 | if (!dentry) | |
806 | goto out_shm_unlock; | |
807 | ||
808 | error = -ENFILE; | |
809 | file = get_empty_filp(); | |
810 | if (!file) | |
811 | goto out_dentry; | |
812 | ||
813 | error = -ENOSPC; | |
814 | inode = hugetlbfs_get_inode(root->d_sb, current->fsuid, | |
815 | current->fsgid, S_IFREG | S_IRWXUGO, 0); | |
816 | if (!inode) | |
817 | goto out_file; | |
818 | ||
b45b5bd6 | 819 | error = -ENOMEM; |
a43a8c39 | 820 | if (hugetlb_reserve_pages(inode, 0, size >> HPAGE_SHIFT)) |
b45b5bd6 DG |
821 | goto out_inode; |
822 | ||
1da177e4 LT |
823 | d_instantiate(dentry, inode); |
824 | inode->i_size = size; | |
825 | inode->i_nlink = 0; | |
b39424e2 JS |
826 | file->f_path.mnt = mntget(hugetlbfs_vfsmount); |
827 | file->f_path.dentry = dentry; | |
1da177e4 LT |
828 | file->f_mapping = inode->i_mapping; |
829 | file->f_op = &hugetlbfs_file_operations; | |
830 | file->f_mode = FMODE_WRITE | FMODE_READ; | |
831 | return file; | |
832 | ||
b45b5bd6 DG |
833 | out_inode: |
834 | iput(inode); | |
1da177e4 LT |
835 | out_file: |
836 | put_filp(file); | |
837 | out_dentry: | |
838 | dput(dentry); | |
839 | out_shm_unlock: | |
840 | user_shm_unlock(size, current->user); | |
841 | return ERR_PTR(error); | |
842 | } | |
843 | ||
844 | static int __init init_hugetlbfs_fs(void) | |
845 | { | |
846 | int error; | |
847 | struct vfsmount *vfsmount; | |
848 | ||
849 | hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache", | |
850 | sizeof(struct hugetlbfs_inode_info), | |
20c2df83 | 851 | 0, 0, init_once); |
1da177e4 LT |
852 | if (hugetlbfs_inode_cachep == NULL) |
853 | return -ENOMEM; | |
854 | ||
855 | error = register_filesystem(&hugetlbfs_fs_type); | |
856 | if (error) | |
857 | goto out; | |
858 | ||
859 | vfsmount = kern_mount(&hugetlbfs_fs_type); | |
860 | ||
861 | if (!IS_ERR(vfsmount)) { | |
862 | hugetlbfs_vfsmount = vfsmount; | |
863 | return 0; | |
864 | } | |
865 | ||
866 | error = PTR_ERR(vfsmount); | |
867 | ||
868 | out: | |
869 | if (error) | |
870 | kmem_cache_destroy(hugetlbfs_inode_cachep); | |
871 | return error; | |
872 | } | |
873 | ||
874 | static void __exit exit_hugetlbfs_fs(void) | |
875 | { | |
876 | kmem_cache_destroy(hugetlbfs_inode_cachep); | |
877 | unregister_filesystem(&hugetlbfs_fs_type); | |
878 | } | |
879 | ||
880 | module_init(init_hugetlbfs_fs) | |
881 | module_exit(exit_hugetlbfs_fs) | |
882 | ||
883 | MODULE_LICENSE("GPL"); |