]>
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 | 84 | /* |
dec4ad86 DG |
85 | * vma address alignment (but not the pgoff alignment) has |
86 | * already been checked by prepare_hugepage_range. If you add | |
87 | * any error returns here, do so after setting VM_HUGETLB, so | |
88 | * is_vm_hugetlb_page tests below unmap_region go the right | |
89 | * way when do_mmap_pgoff unwinds (may be important on powerpc | |
90 | * and ia64). | |
68589bc3 HD |
91 | */ |
92 | vma->vm_flags |= VM_HUGETLB | VM_RESERVED; | |
93 | vma->vm_ops = &hugetlb_vm_ops; | |
1da177e4 | 94 | |
dec4ad86 DG |
95 | if (vma->vm_pgoff & ~(HPAGE_MASK >> PAGE_SHIFT)) |
96 | return -EINVAL; | |
97 | ||
1da177e4 LT |
98 | vma_len = (loff_t)(vma->vm_end - vma->vm_start); |
99 | ||
1b1dcc1b | 100 | mutex_lock(&inode->i_mutex); |
1da177e4 | 101 | file_accessed(file); |
1da177e4 LT |
102 | |
103 | ret = -ENOMEM; | |
104 | len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); | |
1da177e4 | 105 | |
a43a8c39 KC |
106 | if (vma->vm_flags & VM_MAYSHARE && |
107 | hugetlb_reserve_pages(inode, vma->vm_pgoff >> (HPAGE_SHIFT-PAGE_SHIFT), | |
108 | len >> HPAGE_SHIFT)) | |
109 | goto out; | |
b45b5bd6 | 110 | |
4c887265 AL |
111 | ret = 0; |
112 | hugetlb_prefault_arch_hook(vma->vm_mm); | |
b6174df5 | 113 | if (vma->vm_flags & VM_WRITE && inode->i_size < len) |
1da177e4 LT |
114 | inode->i_size = len; |
115 | out: | |
1b1dcc1b | 116 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
117 | |
118 | return ret; | |
119 | } | |
120 | ||
121 | /* | |
508034a3 | 122 | * Called under down_write(mmap_sem). |
1da177e4 LT |
123 | */ |
124 | ||
d2ba27e8 | 125 | #ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA |
1da177e4 LT |
126 | static unsigned long |
127 | hugetlb_get_unmapped_area(struct file *file, unsigned long addr, | |
128 | unsigned long len, unsigned long pgoff, unsigned long flags) | |
129 | { | |
130 | struct mm_struct *mm = current->mm; | |
131 | struct vm_area_struct *vma; | |
132 | unsigned long start_addr; | |
133 | ||
134 | if (len & ~HPAGE_MASK) | |
135 | return -EINVAL; | |
136 | if (len > TASK_SIZE) | |
137 | return -ENOMEM; | |
138 | ||
036e0856 | 139 | if (flags & MAP_FIXED) { |
dec4ad86 | 140 | if (prepare_hugepage_range(addr, len)) |
036e0856 BH |
141 | return -EINVAL; |
142 | return addr; | |
143 | } | |
144 | ||
1da177e4 LT |
145 | if (addr) { |
146 | addr = ALIGN(addr, HPAGE_SIZE); | |
147 | vma = find_vma(mm, addr); | |
148 | if (TASK_SIZE - len >= addr && | |
149 | (!vma || addr + len <= vma->vm_start)) | |
150 | return addr; | |
151 | } | |
152 | ||
153 | start_addr = mm->free_area_cache; | |
154 | ||
1363c3cd WW |
155 | if (len <= mm->cached_hole_size) |
156 | start_addr = TASK_UNMAPPED_BASE; | |
157 | ||
1da177e4 LT |
158 | full_search: |
159 | addr = ALIGN(start_addr, HPAGE_SIZE); | |
160 | ||
161 | for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { | |
162 | /* At this point: (!vma || addr < vma->vm_end). */ | |
163 | if (TASK_SIZE - len < addr) { | |
164 | /* | |
165 | * Start a new search - just in case we missed | |
166 | * some holes. | |
167 | */ | |
168 | if (start_addr != TASK_UNMAPPED_BASE) { | |
169 | start_addr = TASK_UNMAPPED_BASE; | |
170 | goto full_search; | |
171 | } | |
172 | return -ENOMEM; | |
173 | } | |
174 | ||
175 | if (!vma || addr + len <= vma->vm_start) | |
176 | return addr; | |
177 | addr = ALIGN(vma->vm_end, HPAGE_SIZE); | |
178 | } | |
179 | } | |
180 | #endif | |
181 | ||
182 | /* | |
183 | * Read a page. Again trivial. If it didn't already exist | |
184 | * in the page cache, it is zero-filled. | |
185 | */ | |
186 | static int hugetlbfs_readpage(struct file *file, struct page * page) | |
187 | { | |
188 | unlock_page(page); | |
189 | return -EINVAL; | |
190 | } | |
191 | ||
800d15a5 NP |
192 | static int hugetlbfs_write_begin(struct file *file, |
193 | struct address_space *mapping, | |
194 | loff_t pos, unsigned len, unsigned flags, | |
195 | struct page **pagep, void **fsdata) | |
1da177e4 LT |
196 | { |
197 | return -EINVAL; | |
198 | } | |
199 | ||
800d15a5 NP |
200 | static int hugetlbfs_write_end(struct file *file, struct address_space *mapping, |
201 | loff_t pos, unsigned len, unsigned copied, | |
202 | struct page *page, void *fsdata) | |
1da177e4 | 203 | { |
800d15a5 | 204 | BUG(); |
1da177e4 LT |
205 | return -EINVAL; |
206 | } | |
207 | ||
1da177e4 LT |
208 | static void truncate_huge_page(struct page *page) |
209 | { | |
fba2591b | 210 | cancel_dirty_page(page, /* No IO accounting for huge pages? */0); |
1da177e4 LT |
211 | ClearPageUptodate(page); |
212 | remove_from_page_cache(page); | |
213 | put_page(page); | |
214 | } | |
215 | ||
b45b5bd6 | 216 | static void truncate_hugepages(struct inode *inode, loff_t lstart) |
1da177e4 | 217 | { |
b45b5bd6 | 218 | struct address_space *mapping = &inode->i_data; |
1da177e4 LT |
219 | const pgoff_t start = lstart >> HPAGE_SHIFT; |
220 | struct pagevec pvec; | |
221 | pgoff_t next; | |
a43a8c39 | 222 | int i, freed = 0; |
1da177e4 LT |
223 | |
224 | pagevec_init(&pvec, 0); | |
225 | next = start; | |
226 | while (1) { | |
227 | if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { | |
228 | if (next == start) | |
229 | break; | |
230 | next = start; | |
231 | continue; | |
232 | } | |
233 | ||
234 | for (i = 0; i < pagevec_count(&pvec); ++i) { | |
235 | struct page *page = pvec.pages[i]; | |
236 | ||
237 | lock_page(page); | |
238 | if (page->index > next) | |
239 | next = page->index; | |
240 | ++next; | |
241 | truncate_huge_page(page); | |
242 | unlock_page(page); | |
243 | hugetlb_put_quota(mapping); | |
a43a8c39 | 244 | freed++; |
1da177e4 LT |
245 | } |
246 | huge_pagevec_release(&pvec); | |
247 | } | |
248 | BUG_ON(!lstart && mapping->nrpages); | |
a43a8c39 | 249 | hugetlb_unreserve_pages(inode, start, freed); |
1da177e4 LT |
250 | } |
251 | ||
252 | static void hugetlbfs_delete_inode(struct inode *inode) | |
253 | { | |
b45b5bd6 | 254 | truncate_hugepages(inode, 0); |
149f4211 CH |
255 | clear_inode(inode); |
256 | } | |
257 | ||
ddc0a51d | 258 | static void hugetlbfs_forget_inode(struct inode *inode) __releases(inode_lock) |
1da177e4 | 259 | { |
0b1533f6 CH |
260 | struct super_block *sb = inode->i_sb; |
261 | ||
262 | if (!hlist_unhashed(&inode->i_hash)) { | |
263 | if (!(inode->i_state & (I_DIRTY|I_LOCK))) | |
264 | list_move(&inode->i_list, &inode_unused); | |
265 | inodes_stat.nr_unused++; | |
266 | if (!sb || (sb->s_flags & MS_ACTIVE)) { | |
267 | spin_unlock(&inode_lock); | |
268 | return; | |
269 | } | |
270 | inode->i_state |= I_WILL_FREE; | |
1da177e4 | 271 | spin_unlock(&inode_lock); |
0b1533f6 CH |
272 | /* |
273 | * write_inode_now is a noop as we set BDI_CAP_NO_WRITEBACK | |
274 | * in our backing_dev_info. | |
275 | */ | |
276 | write_inode_now(inode, 1); | |
277 | spin_lock(&inode_lock); | |
278 | inode->i_state &= ~I_WILL_FREE; | |
279 | inodes_stat.nr_unused--; | |
280 | hlist_del_init(&inode->i_hash); | |
1da177e4 | 281 | } |
1da177e4 LT |
282 | list_del_init(&inode->i_list); |
283 | list_del_init(&inode->i_sb_list); | |
284 | inode->i_state |= I_FREEING; | |
285 | inodes_stat.nr_inodes--; | |
286 | spin_unlock(&inode_lock); | |
b45b5bd6 | 287 | truncate_hugepages(inode, 0); |
1da177e4 LT |
288 | clear_inode(inode); |
289 | destroy_inode(inode); | |
290 | } | |
291 | ||
292 | static void hugetlbfs_drop_inode(struct inode *inode) | |
293 | { | |
294 | if (!inode->i_nlink) | |
6b09b9df | 295 | generic_delete_inode(inode); |
1da177e4 LT |
296 | else |
297 | hugetlbfs_forget_inode(inode); | |
298 | } | |
299 | ||
1da177e4 | 300 | static inline void |
856fc295 | 301 | hugetlb_vmtruncate_list(struct prio_tree_root *root, pgoff_t pgoff) |
1da177e4 LT |
302 | { |
303 | struct vm_area_struct *vma; | |
304 | struct prio_tree_iter iter; | |
305 | ||
856fc295 | 306 | vma_prio_tree_foreach(vma, &iter, root, pgoff, ULONG_MAX) { |
1da177e4 LT |
307 | unsigned long v_offset; |
308 | ||
1da177e4 | 309 | /* |
856fc295 HD |
310 | * Can the expression below overflow on 32-bit arches? |
311 | * No, because the prio_tree returns us only those vmas | |
312 | * which overlap the truncated area starting at pgoff, | |
313 | * and no vma on a 32-bit arch can span beyond the 4GB. | |
1da177e4 | 314 | */ |
856fc295 HD |
315 | if (vma->vm_pgoff < pgoff) |
316 | v_offset = (pgoff - vma->vm_pgoff) << PAGE_SHIFT; | |
317 | else | |
1da177e4 LT |
318 | v_offset = 0; |
319 | ||
502717f4 | 320 | __unmap_hugepage_range(vma, |
508034a3 | 321 | vma->vm_start + v_offset, vma->vm_end); |
1da177e4 LT |
322 | } |
323 | } | |
324 | ||
325 | /* | |
326 | * Expanding truncates are not allowed. | |
327 | */ | |
328 | static int hugetlb_vmtruncate(struct inode *inode, loff_t offset) | |
329 | { | |
856fc295 | 330 | pgoff_t pgoff; |
1da177e4 LT |
331 | struct address_space *mapping = inode->i_mapping; |
332 | ||
333 | if (offset > inode->i_size) | |
334 | return -EINVAL; | |
335 | ||
336 | BUG_ON(offset & ~HPAGE_MASK); | |
856fc295 | 337 | pgoff = offset >> PAGE_SHIFT; |
1da177e4 LT |
338 | |
339 | inode->i_size = offset; | |
340 | spin_lock(&mapping->i_mmap_lock); | |
341 | if (!prio_tree_empty(&mapping->i_mmap)) | |
342 | hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff); | |
343 | spin_unlock(&mapping->i_mmap_lock); | |
b45b5bd6 | 344 | truncate_hugepages(inode, offset); |
1da177e4 LT |
345 | return 0; |
346 | } | |
347 | ||
348 | static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr) | |
349 | { | |
350 | struct inode *inode = dentry->d_inode; | |
351 | int error; | |
352 | unsigned int ia_valid = attr->ia_valid; | |
353 | ||
354 | BUG_ON(!inode); | |
355 | ||
356 | error = inode_change_ok(inode, attr); | |
357 | if (error) | |
358 | goto out; | |
359 | ||
360 | if (ia_valid & ATTR_SIZE) { | |
361 | error = -EINVAL; | |
362 | if (!(attr->ia_size & ~HPAGE_MASK)) | |
363 | error = hugetlb_vmtruncate(inode, attr->ia_size); | |
364 | if (error) | |
365 | goto out; | |
366 | attr->ia_valid &= ~ATTR_SIZE; | |
367 | } | |
368 | error = inode_setattr(inode, attr); | |
369 | out: | |
370 | return error; | |
371 | } | |
372 | ||
373 | static struct inode *hugetlbfs_get_inode(struct super_block *sb, uid_t uid, | |
374 | gid_t gid, int mode, dev_t dev) | |
375 | { | |
376 | struct inode *inode; | |
1da177e4 LT |
377 | |
378 | inode = new_inode(sb); | |
379 | if (inode) { | |
380 | struct hugetlbfs_inode_info *info; | |
381 | inode->i_mode = mode; | |
382 | inode->i_uid = uid; | |
383 | inode->i_gid = gid; | |
1da177e4 LT |
384 | inode->i_blocks = 0; |
385 | inode->i_mapping->a_ops = &hugetlbfs_aops; | |
386 | inode->i_mapping->backing_dev_info =&hugetlbfs_backing_dev_info; | |
387 | inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; | |
a43a8c39 | 388 | INIT_LIST_HEAD(&inode->i_mapping->private_list); |
1da177e4 | 389 | info = HUGETLBFS_I(inode); |
7339ff83 | 390 | mpol_shared_policy_init(&info->policy, MPOL_DEFAULT, NULL); |
1da177e4 LT |
391 | switch (mode & S_IFMT) { |
392 | default: | |
393 | init_special_inode(inode, mode, dev); | |
394 | break; | |
395 | case S_IFREG: | |
396 | inode->i_op = &hugetlbfs_inode_operations; | |
397 | inode->i_fop = &hugetlbfs_file_operations; | |
398 | break; | |
399 | case S_IFDIR: | |
400 | inode->i_op = &hugetlbfs_dir_inode_operations; | |
401 | inode->i_fop = &simple_dir_operations; | |
402 | ||
403 | /* directory inodes start off with i_nlink == 2 (for "." entry) */ | |
d8c76e6f | 404 | inc_nlink(inode); |
1da177e4 LT |
405 | break; |
406 | case S_IFLNK: | |
407 | inode->i_op = &page_symlink_inode_operations; | |
408 | break; | |
409 | } | |
410 | } | |
411 | return inode; | |
412 | } | |
413 | ||
414 | /* | |
415 | * File creation. Allocate an inode, and we're done.. | |
416 | */ | |
417 | static int hugetlbfs_mknod(struct inode *dir, | |
418 | struct dentry *dentry, int mode, dev_t dev) | |
419 | { | |
420 | struct inode *inode; | |
421 | int error = -ENOSPC; | |
422 | gid_t gid; | |
423 | ||
424 | if (dir->i_mode & S_ISGID) { | |
425 | gid = dir->i_gid; | |
426 | if (S_ISDIR(mode)) | |
427 | mode |= S_ISGID; | |
428 | } else { | |
429 | gid = current->fsgid; | |
430 | } | |
431 | inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, gid, mode, dev); | |
432 | if (inode) { | |
433 | dir->i_ctime = dir->i_mtime = CURRENT_TIME; | |
434 | d_instantiate(dentry, inode); | |
435 | dget(dentry); /* Extra count - pin the dentry in core */ | |
436 | error = 0; | |
437 | } | |
438 | return error; | |
439 | } | |
440 | ||
441 | static int hugetlbfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) | |
442 | { | |
443 | int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0); | |
444 | if (!retval) | |
d8c76e6f | 445 | inc_nlink(dir); |
1da177e4 LT |
446 | return retval; |
447 | } | |
448 | ||
449 | static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd) | |
450 | { | |
451 | return hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0); | |
452 | } | |
453 | ||
454 | static int hugetlbfs_symlink(struct inode *dir, | |
455 | struct dentry *dentry, const char *symname) | |
456 | { | |
457 | struct inode *inode; | |
458 | int error = -ENOSPC; | |
459 | gid_t gid; | |
460 | ||
461 | if (dir->i_mode & S_ISGID) | |
462 | gid = dir->i_gid; | |
463 | else | |
464 | gid = current->fsgid; | |
465 | ||
466 | inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, | |
467 | gid, S_IFLNK|S_IRWXUGO, 0); | |
468 | if (inode) { | |
469 | int l = strlen(symname)+1; | |
470 | error = page_symlink(inode, symname, l); | |
471 | if (!error) { | |
472 | d_instantiate(dentry, inode); | |
473 | dget(dentry); | |
474 | } else | |
475 | iput(inode); | |
476 | } | |
477 | dir->i_ctime = dir->i_mtime = CURRENT_TIME; | |
478 | ||
479 | return error; | |
480 | } | |
481 | ||
482 | /* | |
6649a386 | 483 | * mark the head page dirty |
1da177e4 LT |
484 | */ |
485 | static int hugetlbfs_set_page_dirty(struct page *page) | |
486 | { | |
d85f3385 | 487 | struct page *head = compound_head(page); |
6649a386 KC |
488 | |
489 | SetPageDirty(head); | |
1da177e4 LT |
490 | return 0; |
491 | } | |
492 | ||
726c3342 | 493 | static int hugetlbfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1da177e4 | 494 | { |
726c3342 | 495 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(dentry->d_sb); |
1da177e4 LT |
496 | |
497 | buf->f_type = HUGETLBFS_MAGIC; | |
498 | buf->f_bsize = HPAGE_SIZE; | |
499 | if (sbinfo) { | |
500 | spin_lock(&sbinfo->stat_lock); | |
74a8a65c DG |
501 | /* If no limits set, just report 0 for max/free/used |
502 | * blocks, like simple_statfs() */ | |
503 | if (sbinfo->max_blocks >= 0) { | |
504 | buf->f_blocks = sbinfo->max_blocks; | |
505 | buf->f_bavail = buf->f_bfree = sbinfo->free_blocks; | |
506 | buf->f_files = sbinfo->max_inodes; | |
507 | buf->f_ffree = sbinfo->free_inodes; | |
508 | } | |
1da177e4 LT |
509 | spin_unlock(&sbinfo->stat_lock); |
510 | } | |
511 | buf->f_namelen = NAME_MAX; | |
512 | return 0; | |
513 | } | |
514 | ||
515 | static void hugetlbfs_put_super(struct super_block *sb) | |
516 | { | |
517 | struct hugetlbfs_sb_info *sbi = HUGETLBFS_SB(sb); | |
518 | ||
519 | if (sbi) { | |
520 | sb->s_fs_info = NULL; | |
521 | kfree(sbi); | |
522 | } | |
523 | } | |
524 | ||
96527980 CH |
525 | static inline int hugetlbfs_dec_free_inodes(struct hugetlbfs_sb_info *sbinfo) |
526 | { | |
527 | if (sbinfo->free_inodes >= 0) { | |
528 | spin_lock(&sbinfo->stat_lock); | |
529 | if (unlikely(!sbinfo->free_inodes)) { | |
530 | spin_unlock(&sbinfo->stat_lock); | |
531 | return 0; | |
532 | } | |
533 | sbinfo->free_inodes--; | |
534 | spin_unlock(&sbinfo->stat_lock); | |
535 | } | |
536 | ||
537 | return 1; | |
538 | } | |
539 | ||
540 | static void hugetlbfs_inc_free_inodes(struct hugetlbfs_sb_info *sbinfo) | |
541 | { | |
542 | if (sbinfo->free_inodes >= 0) { | |
543 | spin_lock(&sbinfo->stat_lock); | |
544 | sbinfo->free_inodes++; | |
545 | spin_unlock(&sbinfo->stat_lock); | |
546 | } | |
547 | } | |
548 | ||
549 | ||
e18b890b | 550 | static struct kmem_cache *hugetlbfs_inode_cachep; |
1da177e4 LT |
551 | |
552 | static struct inode *hugetlbfs_alloc_inode(struct super_block *sb) | |
553 | { | |
96527980 | 554 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb); |
1da177e4 LT |
555 | struct hugetlbfs_inode_info *p; |
556 | ||
96527980 CH |
557 | if (unlikely(!hugetlbfs_dec_free_inodes(sbinfo))) |
558 | return NULL; | |
e94b1766 | 559 | p = kmem_cache_alloc(hugetlbfs_inode_cachep, GFP_KERNEL); |
96527980 CH |
560 | if (unlikely(!p)) { |
561 | hugetlbfs_inc_free_inodes(sbinfo); | |
1da177e4 | 562 | return NULL; |
96527980 | 563 | } |
1da177e4 LT |
564 | return &p->vfs_inode; |
565 | } | |
566 | ||
1da177e4 LT |
567 | static void hugetlbfs_destroy_inode(struct inode *inode) |
568 | { | |
96527980 | 569 | hugetlbfs_inc_free_inodes(HUGETLBFS_SB(inode->i_sb)); |
1da177e4 LT |
570 | mpol_free_shared_policy(&HUGETLBFS_I(inode)->policy); |
571 | kmem_cache_free(hugetlbfs_inode_cachep, HUGETLBFS_I(inode)); | |
572 | } | |
573 | ||
f5e54d6e | 574 | static const struct address_space_operations hugetlbfs_aops = { |
1da177e4 | 575 | .readpage = hugetlbfs_readpage, |
800d15a5 NP |
576 | .write_begin = hugetlbfs_write_begin, |
577 | .write_end = hugetlbfs_write_end, | |
1da177e4 LT |
578 | .set_page_dirty = hugetlbfs_set_page_dirty, |
579 | }; | |
580 | ||
96527980 | 581 | |
e18b890b | 582 | static void init_once(void *foo, struct kmem_cache *cachep, unsigned long flags) |
96527980 CH |
583 | { |
584 | struct hugetlbfs_inode_info *ei = (struct hugetlbfs_inode_info *)foo; | |
585 | ||
a35afb83 | 586 | inode_init_once(&ei->vfs_inode); |
96527980 CH |
587 | } |
588 | ||
4b6f5d20 | 589 | const struct file_operations hugetlbfs_file_operations = { |
1da177e4 LT |
590 | .mmap = hugetlbfs_file_mmap, |
591 | .fsync = simple_sync_file, | |
592 | .get_unmapped_area = hugetlb_get_unmapped_area, | |
593 | }; | |
594 | ||
92e1d5be | 595 | static const struct inode_operations hugetlbfs_dir_inode_operations = { |
1da177e4 LT |
596 | .create = hugetlbfs_create, |
597 | .lookup = simple_lookup, | |
598 | .link = simple_link, | |
599 | .unlink = simple_unlink, | |
600 | .symlink = hugetlbfs_symlink, | |
601 | .mkdir = hugetlbfs_mkdir, | |
602 | .rmdir = simple_rmdir, | |
603 | .mknod = hugetlbfs_mknod, | |
604 | .rename = simple_rename, | |
605 | .setattr = hugetlbfs_setattr, | |
606 | }; | |
607 | ||
92e1d5be | 608 | static const struct inode_operations hugetlbfs_inode_operations = { |
1da177e4 LT |
609 | .setattr = hugetlbfs_setattr, |
610 | }; | |
611 | ||
ee9b6d61 | 612 | static const struct super_operations hugetlbfs_ops = { |
1da177e4 LT |
613 | .alloc_inode = hugetlbfs_alloc_inode, |
614 | .destroy_inode = hugetlbfs_destroy_inode, | |
615 | .statfs = hugetlbfs_statfs, | |
149f4211 | 616 | .delete_inode = hugetlbfs_delete_inode, |
1da177e4 LT |
617 | .drop_inode = hugetlbfs_drop_inode, |
618 | .put_super = hugetlbfs_put_super, | |
619 | }; | |
620 | ||
621 | static int | |
622 | hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) | |
623 | { | |
e73a75fa RD |
624 | char *p, *rest; |
625 | substring_t args[MAX_OPT_ARGS]; | |
626 | int option; | |
1da177e4 LT |
627 | |
628 | if (!options) | |
629 | return 0; | |
1da177e4 | 630 | |
e73a75fa RD |
631 | while ((p = strsep(&options, ",")) != NULL) { |
632 | int token; | |
b4c07bce LS |
633 | if (!*p) |
634 | continue; | |
e73a75fa RD |
635 | |
636 | token = match_token(p, tokens, args); | |
637 | switch (token) { | |
638 | case Opt_uid: | |
639 | if (match_int(&args[0], &option)) | |
640 | goto bad_val; | |
641 | pconfig->uid = option; | |
642 | break; | |
643 | ||
644 | case Opt_gid: | |
645 | if (match_int(&args[0], &option)) | |
646 | goto bad_val; | |
647 | pconfig->gid = option; | |
648 | break; | |
649 | ||
650 | case Opt_mode: | |
651 | if (match_octal(&args[0], &option)) | |
652 | goto bad_val; | |
653 | pconfig->mode = option & 0777U; | |
654 | break; | |
655 | ||
656 | case Opt_size: { | |
657 | unsigned long long size; | |
658 | /* memparse() will accept a K/M/G without a digit */ | |
659 | if (!isdigit(*args[0].from)) | |
660 | goto bad_val; | |
661 | size = memparse(args[0].from, &rest); | |
1da177e4 LT |
662 | if (*rest == '%') { |
663 | size <<= HPAGE_SHIFT; | |
664 | size *= max_huge_pages; | |
665 | do_div(size, 100); | |
1da177e4 | 666 | } |
1da177e4 | 667 | pconfig->nr_blocks = (size >> HPAGE_SHIFT); |
e73a75fa RD |
668 | break; |
669 | } | |
1da177e4 | 670 | |
e73a75fa RD |
671 | case Opt_nr_inodes: |
672 | /* memparse() will accept a K/M/G without a digit */ | |
673 | if (!isdigit(*args[0].from)) | |
674 | goto bad_val; | |
675 | pconfig->nr_inodes = memparse(args[0].from, &rest); | |
676 | break; | |
677 | ||
678 | default: | |
b4c07bce LS |
679 | printk(KERN_ERR "hugetlbfs: Bad mount option: \"%s\"\n", |
680 | p); | |
681 | return -EINVAL; | |
e73a75fa RD |
682 | break; |
683 | } | |
1da177e4 LT |
684 | } |
685 | return 0; | |
e73a75fa RD |
686 | |
687 | bad_val: | |
688 | printk(KERN_ERR "hugetlbfs: Bad value '%s' for mount option '%s'\n", | |
689 | args[0].from, p); | |
690 | return 1; | |
1da177e4 LT |
691 | } |
692 | ||
693 | static int | |
694 | hugetlbfs_fill_super(struct super_block *sb, void *data, int silent) | |
695 | { | |
696 | struct inode * inode; | |
697 | struct dentry * root; | |
698 | int ret; | |
699 | struct hugetlbfs_config config; | |
700 | struct hugetlbfs_sb_info *sbinfo; | |
701 | ||
702 | config.nr_blocks = -1; /* No limit on size by default */ | |
703 | config.nr_inodes = -1; /* No limit on number of inodes by default */ | |
704 | config.uid = current->fsuid; | |
705 | config.gid = current->fsgid; | |
706 | config.mode = 0755; | |
707 | ret = hugetlbfs_parse_options(data, &config); | |
1da177e4 LT |
708 | if (ret) |
709 | return ret; | |
710 | ||
711 | sbinfo = kmalloc(sizeof(struct hugetlbfs_sb_info), GFP_KERNEL); | |
712 | if (!sbinfo) | |
713 | return -ENOMEM; | |
714 | sb->s_fs_info = sbinfo; | |
715 | spin_lock_init(&sbinfo->stat_lock); | |
716 | sbinfo->max_blocks = config.nr_blocks; | |
717 | sbinfo->free_blocks = config.nr_blocks; | |
718 | sbinfo->max_inodes = config.nr_inodes; | |
719 | sbinfo->free_inodes = config.nr_inodes; | |
720 | sb->s_maxbytes = MAX_LFS_FILESIZE; | |
721 | sb->s_blocksize = HPAGE_SIZE; | |
722 | sb->s_blocksize_bits = HPAGE_SHIFT; | |
723 | sb->s_magic = HUGETLBFS_MAGIC; | |
724 | sb->s_op = &hugetlbfs_ops; | |
725 | sb->s_time_gran = 1; | |
726 | inode = hugetlbfs_get_inode(sb, config.uid, config.gid, | |
727 | S_IFDIR | config.mode, 0); | |
728 | if (!inode) | |
729 | goto out_free; | |
730 | ||
731 | root = d_alloc_root(inode); | |
732 | if (!root) { | |
733 | iput(inode); | |
734 | goto out_free; | |
735 | } | |
736 | sb->s_root = root; | |
737 | return 0; | |
738 | out_free: | |
739 | kfree(sbinfo); | |
740 | return -ENOMEM; | |
741 | } | |
742 | ||
743 | int hugetlb_get_quota(struct address_space *mapping) | |
744 | { | |
745 | int ret = 0; | |
746 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); | |
747 | ||
748 | if (sbinfo->free_blocks > -1) { | |
749 | spin_lock(&sbinfo->stat_lock); | |
750 | if (sbinfo->free_blocks > 0) | |
751 | sbinfo->free_blocks--; | |
752 | else | |
753 | ret = -ENOMEM; | |
754 | spin_unlock(&sbinfo->stat_lock); | |
755 | } | |
756 | ||
757 | return ret; | |
758 | } | |
759 | ||
760 | void hugetlb_put_quota(struct address_space *mapping) | |
761 | { | |
762 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); | |
763 | ||
764 | if (sbinfo->free_blocks > -1) { | |
765 | spin_lock(&sbinfo->stat_lock); | |
766 | sbinfo->free_blocks++; | |
767 | spin_unlock(&sbinfo->stat_lock); | |
768 | } | |
769 | } | |
770 | ||
454e2398 DH |
771 | static int hugetlbfs_get_sb(struct file_system_type *fs_type, |
772 | int flags, const char *dev_name, void *data, struct vfsmount *mnt) | |
1da177e4 | 773 | { |
454e2398 | 774 | return get_sb_nodev(fs_type, flags, data, hugetlbfs_fill_super, mnt); |
1da177e4 LT |
775 | } |
776 | ||
777 | static struct file_system_type hugetlbfs_fs_type = { | |
778 | .name = "hugetlbfs", | |
779 | .get_sb = hugetlbfs_get_sb, | |
780 | .kill_sb = kill_litter_super, | |
781 | }; | |
782 | ||
783 | static struct vfsmount *hugetlbfs_vfsmount; | |
784 | ||
1da177e4 LT |
785 | static int can_do_hugetlb_shm(void) |
786 | { | |
787 | return likely(capable(CAP_IPC_LOCK) || | |
788 | in_group_p(sysctl_hugetlb_shm_group) || | |
789 | can_do_mlock()); | |
790 | } | |
791 | ||
9d66586f | 792 | struct file *hugetlb_file_setup(const char *name, size_t size) |
1da177e4 LT |
793 | { |
794 | int error = -ENOMEM; | |
795 | struct file *file; | |
796 | struct inode *inode; | |
797 | struct dentry *dentry, *root; | |
798 | struct qstr quick_string; | |
1da177e4 | 799 | |
5bc98594 AM |
800 | if (!hugetlbfs_vfsmount) |
801 | return ERR_PTR(-ENOENT); | |
802 | ||
1da177e4 LT |
803 | if (!can_do_hugetlb_shm()) |
804 | return ERR_PTR(-EPERM); | |
805 | ||
1da177e4 LT |
806 | if (!user_shm_lock(size, current->user)) |
807 | return ERR_PTR(-ENOMEM); | |
808 | ||
809 | root = hugetlbfs_vfsmount->mnt_root; | |
9d66586f | 810 | quick_string.name = name; |
1da177e4 LT |
811 | quick_string.len = strlen(quick_string.name); |
812 | quick_string.hash = 0; | |
813 | dentry = d_alloc(root, &quick_string); | |
814 | if (!dentry) | |
815 | goto out_shm_unlock; | |
816 | ||
817 | error = -ENFILE; | |
818 | file = get_empty_filp(); | |
819 | if (!file) | |
820 | goto out_dentry; | |
821 | ||
822 | error = -ENOSPC; | |
823 | inode = hugetlbfs_get_inode(root->d_sb, current->fsuid, | |
824 | current->fsgid, S_IFREG | S_IRWXUGO, 0); | |
825 | if (!inode) | |
826 | goto out_file; | |
827 | ||
b45b5bd6 | 828 | error = -ENOMEM; |
a43a8c39 | 829 | if (hugetlb_reserve_pages(inode, 0, size >> HPAGE_SHIFT)) |
b45b5bd6 DG |
830 | goto out_inode; |
831 | ||
1da177e4 LT |
832 | d_instantiate(dentry, inode); |
833 | inode->i_size = size; | |
834 | inode->i_nlink = 0; | |
b39424e2 JS |
835 | file->f_path.mnt = mntget(hugetlbfs_vfsmount); |
836 | file->f_path.dentry = dentry; | |
1da177e4 LT |
837 | file->f_mapping = inode->i_mapping; |
838 | file->f_op = &hugetlbfs_file_operations; | |
839 | file->f_mode = FMODE_WRITE | FMODE_READ; | |
840 | return file; | |
841 | ||
b45b5bd6 DG |
842 | out_inode: |
843 | iput(inode); | |
1da177e4 LT |
844 | out_file: |
845 | put_filp(file); | |
846 | out_dentry: | |
847 | dput(dentry); | |
848 | out_shm_unlock: | |
849 | user_shm_unlock(size, current->user); | |
850 | return ERR_PTR(error); | |
851 | } | |
852 | ||
853 | static int __init init_hugetlbfs_fs(void) | |
854 | { | |
855 | int error; | |
856 | struct vfsmount *vfsmount; | |
857 | ||
858 | hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache", | |
859 | sizeof(struct hugetlbfs_inode_info), | |
20c2df83 | 860 | 0, 0, init_once); |
1da177e4 LT |
861 | if (hugetlbfs_inode_cachep == NULL) |
862 | return -ENOMEM; | |
863 | ||
864 | error = register_filesystem(&hugetlbfs_fs_type); | |
865 | if (error) | |
866 | goto out; | |
867 | ||
868 | vfsmount = kern_mount(&hugetlbfs_fs_type); | |
869 | ||
870 | if (!IS_ERR(vfsmount)) { | |
871 | hugetlbfs_vfsmount = vfsmount; | |
872 | return 0; | |
873 | } | |
874 | ||
875 | error = PTR_ERR(vfsmount); | |
876 | ||
877 | out: | |
878 | if (error) | |
879 | kmem_cache_destroy(hugetlbfs_inode_cachep); | |
880 | return error; | |
881 | } | |
882 | ||
883 | static void __exit exit_hugetlbfs_fs(void) | |
884 | { | |
885 | kmem_cache_destroy(hugetlbfs_inode_cachep); | |
886 | unregister_filesystem(&hugetlbfs_fs_type); | |
887 | } | |
888 | ||
889 | module_init(init_hugetlbfs_fs) | |
890 | module_exit(exit_hugetlbfs_fs) | |
891 | ||
892 | MODULE_LICENSE("GPL"); |