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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 */ | |
e4ad08fe | 48 | .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK, |
1da177e4 LT |
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 | |
a1e78772 MG |
106 | if (hugetlb_reserve_pages(inode, |
107 | vma->vm_pgoff >> (HPAGE_SHIFT-PAGE_SHIFT), | |
108 | len >> HPAGE_SHIFT, vma)) | |
a43a8c39 | 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 | ||
e63e1e5a BP |
182 | static int |
183 | hugetlbfs_read_actor(struct page *page, unsigned long offset, | |
184 | char __user *buf, unsigned long count, | |
185 | unsigned long size) | |
186 | { | |
187 | char *kaddr; | |
188 | unsigned long left, copied = 0; | |
189 | int i, chunksize; | |
190 | ||
191 | if (size > count) | |
192 | size = count; | |
193 | ||
194 | /* Find which 4k chunk and offset with in that chunk */ | |
195 | i = offset >> PAGE_CACHE_SHIFT; | |
196 | offset = offset & ~PAGE_CACHE_MASK; | |
197 | ||
198 | while (size) { | |
199 | chunksize = PAGE_CACHE_SIZE; | |
200 | if (offset) | |
201 | chunksize -= offset; | |
202 | if (chunksize > size) | |
203 | chunksize = size; | |
204 | kaddr = kmap(&page[i]); | |
205 | left = __copy_to_user(buf, kaddr + offset, chunksize); | |
206 | kunmap(&page[i]); | |
207 | if (left) { | |
208 | copied += (chunksize - left); | |
209 | break; | |
210 | } | |
211 | offset = 0; | |
212 | size -= chunksize; | |
213 | buf += chunksize; | |
214 | copied += chunksize; | |
215 | i++; | |
216 | } | |
217 | return copied ? copied : -EFAULT; | |
218 | } | |
219 | ||
220 | /* | |
221 | * Support for read() - Find the page attached to f_mapping and copy out the | |
222 | * data. Its *very* similar to do_generic_mapping_read(), we can't use that | |
223 | * since it has PAGE_CACHE_SIZE assumptions. | |
224 | */ | |
225 | static ssize_t hugetlbfs_read(struct file *filp, char __user *buf, | |
226 | size_t len, loff_t *ppos) | |
227 | { | |
228 | struct address_space *mapping = filp->f_mapping; | |
229 | struct inode *inode = mapping->host; | |
230 | unsigned long index = *ppos >> HPAGE_SHIFT; | |
231 | unsigned long offset = *ppos & ~HPAGE_MASK; | |
232 | unsigned long end_index; | |
233 | loff_t isize; | |
234 | ssize_t retval = 0; | |
235 | ||
236 | mutex_lock(&inode->i_mutex); | |
237 | ||
238 | /* validate length */ | |
239 | if (len == 0) | |
240 | goto out; | |
241 | ||
242 | isize = i_size_read(inode); | |
243 | if (!isize) | |
244 | goto out; | |
245 | ||
246 | end_index = (isize - 1) >> HPAGE_SHIFT; | |
247 | for (;;) { | |
248 | struct page *page; | |
249 | int nr, ret; | |
250 | ||
251 | /* nr is the maximum number of bytes to copy from this page */ | |
252 | nr = HPAGE_SIZE; | |
253 | if (index >= end_index) { | |
254 | if (index > end_index) | |
255 | goto out; | |
256 | nr = ((isize - 1) & ~HPAGE_MASK) + 1; | |
257 | if (nr <= offset) { | |
258 | goto out; | |
259 | } | |
260 | } | |
261 | nr = nr - offset; | |
262 | ||
263 | /* Find the page */ | |
264 | page = find_get_page(mapping, index); | |
265 | if (unlikely(page == NULL)) { | |
266 | /* | |
267 | * We have a HOLE, zero out the user-buffer for the | |
268 | * length of the hole or request. | |
269 | */ | |
270 | ret = len < nr ? len : nr; | |
271 | if (clear_user(buf, ret)) | |
272 | ret = -EFAULT; | |
273 | } else { | |
274 | /* | |
275 | * We have the page, copy it to user space buffer. | |
276 | */ | |
277 | ret = hugetlbfs_read_actor(page, offset, buf, len, nr); | |
278 | } | |
279 | if (ret < 0) { | |
280 | if (retval == 0) | |
281 | retval = ret; | |
282 | if (page) | |
283 | page_cache_release(page); | |
284 | goto out; | |
285 | } | |
286 | ||
287 | offset += ret; | |
288 | retval += ret; | |
289 | len -= ret; | |
290 | index += offset >> HPAGE_SHIFT; | |
291 | offset &= ~HPAGE_MASK; | |
292 | ||
293 | if (page) | |
294 | page_cache_release(page); | |
295 | ||
296 | /* short read or no more work */ | |
297 | if ((ret != nr) || (len == 0)) | |
298 | break; | |
299 | } | |
300 | out: | |
301 | *ppos = ((loff_t)index << HPAGE_SHIFT) + offset; | |
302 | mutex_unlock(&inode->i_mutex); | |
303 | return retval; | |
304 | } | |
305 | ||
1da177e4 LT |
306 | /* |
307 | * Read a page. Again trivial. If it didn't already exist | |
308 | * in the page cache, it is zero-filled. | |
309 | */ | |
310 | static int hugetlbfs_readpage(struct file *file, struct page * page) | |
311 | { | |
312 | unlock_page(page); | |
313 | return -EINVAL; | |
314 | } | |
315 | ||
800d15a5 NP |
316 | static int hugetlbfs_write_begin(struct file *file, |
317 | struct address_space *mapping, | |
318 | loff_t pos, unsigned len, unsigned flags, | |
319 | struct page **pagep, void **fsdata) | |
1da177e4 LT |
320 | { |
321 | return -EINVAL; | |
322 | } | |
323 | ||
800d15a5 NP |
324 | static int hugetlbfs_write_end(struct file *file, struct address_space *mapping, |
325 | loff_t pos, unsigned len, unsigned copied, | |
326 | struct page *page, void *fsdata) | |
1da177e4 | 327 | { |
800d15a5 | 328 | BUG(); |
1da177e4 LT |
329 | return -EINVAL; |
330 | } | |
331 | ||
1da177e4 LT |
332 | static void truncate_huge_page(struct page *page) |
333 | { | |
fba2591b | 334 | cancel_dirty_page(page, /* No IO accounting for huge pages? */0); |
1da177e4 LT |
335 | ClearPageUptodate(page); |
336 | remove_from_page_cache(page); | |
337 | put_page(page); | |
338 | } | |
339 | ||
b45b5bd6 | 340 | static void truncate_hugepages(struct inode *inode, loff_t lstart) |
1da177e4 | 341 | { |
b45b5bd6 | 342 | struct address_space *mapping = &inode->i_data; |
1da177e4 LT |
343 | const pgoff_t start = lstart >> HPAGE_SHIFT; |
344 | struct pagevec pvec; | |
345 | pgoff_t next; | |
a43a8c39 | 346 | int i, freed = 0; |
1da177e4 LT |
347 | |
348 | pagevec_init(&pvec, 0); | |
349 | next = start; | |
350 | while (1) { | |
351 | if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { | |
352 | if (next == start) | |
353 | break; | |
354 | next = start; | |
355 | continue; | |
356 | } | |
357 | ||
358 | for (i = 0; i < pagevec_count(&pvec); ++i) { | |
359 | struct page *page = pvec.pages[i]; | |
360 | ||
361 | lock_page(page); | |
362 | if (page->index > next) | |
363 | next = page->index; | |
364 | ++next; | |
365 | truncate_huge_page(page); | |
366 | unlock_page(page); | |
a43a8c39 | 367 | freed++; |
1da177e4 LT |
368 | } |
369 | huge_pagevec_release(&pvec); | |
370 | } | |
371 | BUG_ON(!lstart && mapping->nrpages); | |
a43a8c39 | 372 | hugetlb_unreserve_pages(inode, start, freed); |
1da177e4 LT |
373 | } |
374 | ||
375 | static void hugetlbfs_delete_inode(struct inode *inode) | |
376 | { | |
b45b5bd6 | 377 | truncate_hugepages(inode, 0); |
149f4211 CH |
378 | clear_inode(inode); |
379 | } | |
380 | ||
ddc0a51d | 381 | static void hugetlbfs_forget_inode(struct inode *inode) __releases(inode_lock) |
1da177e4 | 382 | { |
0b1533f6 CH |
383 | struct super_block *sb = inode->i_sb; |
384 | ||
385 | if (!hlist_unhashed(&inode->i_hash)) { | |
1c0eeaf5 | 386 | if (!(inode->i_state & (I_DIRTY|I_SYNC))) |
0b1533f6 CH |
387 | list_move(&inode->i_list, &inode_unused); |
388 | inodes_stat.nr_unused++; | |
389 | if (!sb || (sb->s_flags & MS_ACTIVE)) { | |
390 | spin_unlock(&inode_lock); | |
391 | return; | |
392 | } | |
393 | inode->i_state |= I_WILL_FREE; | |
1da177e4 | 394 | spin_unlock(&inode_lock); |
0b1533f6 CH |
395 | /* |
396 | * write_inode_now is a noop as we set BDI_CAP_NO_WRITEBACK | |
397 | * in our backing_dev_info. | |
398 | */ | |
399 | write_inode_now(inode, 1); | |
400 | spin_lock(&inode_lock); | |
401 | inode->i_state &= ~I_WILL_FREE; | |
402 | inodes_stat.nr_unused--; | |
403 | hlist_del_init(&inode->i_hash); | |
1da177e4 | 404 | } |
1da177e4 LT |
405 | list_del_init(&inode->i_list); |
406 | list_del_init(&inode->i_sb_list); | |
407 | inode->i_state |= I_FREEING; | |
408 | inodes_stat.nr_inodes--; | |
409 | spin_unlock(&inode_lock); | |
b45b5bd6 | 410 | truncate_hugepages(inode, 0); |
1da177e4 LT |
411 | clear_inode(inode); |
412 | destroy_inode(inode); | |
413 | } | |
414 | ||
415 | static void hugetlbfs_drop_inode(struct inode *inode) | |
416 | { | |
417 | if (!inode->i_nlink) | |
6b09b9df | 418 | generic_delete_inode(inode); |
1da177e4 LT |
419 | else |
420 | hugetlbfs_forget_inode(inode); | |
421 | } | |
422 | ||
1da177e4 | 423 | static inline void |
856fc295 | 424 | hugetlb_vmtruncate_list(struct prio_tree_root *root, pgoff_t pgoff) |
1da177e4 LT |
425 | { |
426 | struct vm_area_struct *vma; | |
427 | struct prio_tree_iter iter; | |
428 | ||
856fc295 | 429 | vma_prio_tree_foreach(vma, &iter, root, pgoff, ULONG_MAX) { |
1da177e4 LT |
430 | unsigned long v_offset; |
431 | ||
1da177e4 | 432 | /* |
856fc295 HD |
433 | * Can the expression below overflow on 32-bit arches? |
434 | * No, because the prio_tree returns us only those vmas | |
435 | * which overlap the truncated area starting at pgoff, | |
436 | * and no vma on a 32-bit arch can span beyond the 4GB. | |
1da177e4 | 437 | */ |
856fc295 HD |
438 | if (vma->vm_pgoff < pgoff) |
439 | v_offset = (pgoff - vma->vm_pgoff) << PAGE_SHIFT; | |
440 | else | |
1da177e4 LT |
441 | v_offset = 0; |
442 | ||
502717f4 | 443 | __unmap_hugepage_range(vma, |
04f2cbe3 | 444 | vma->vm_start + v_offset, vma->vm_end, NULL); |
1da177e4 LT |
445 | } |
446 | } | |
447 | ||
1da177e4 LT |
448 | static int hugetlb_vmtruncate(struct inode *inode, loff_t offset) |
449 | { | |
856fc295 | 450 | pgoff_t pgoff; |
1da177e4 LT |
451 | struct address_space *mapping = inode->i_mapping; |
452 | ||
1da177e4 | 453 | BUG_ON(offset & ~HPAGE_MASK); |
856fc295 | 454 | pgoff = offset >> PAGE_SHIFT; |
1da177e4 | 455 | |
7aa91e10 | 456 | i_size_write(inode, offset); |
1da177e4 LT |
457 | spin_lock(&mapping->i_mmap_lock); |
458 | if (!prio_tree_empty(&mapping->i_mmap)) | |
459 | hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff); | |
460 | spin_unlock(&mapping->i_mmap_lock); | |
b45b5bd6 | 461 | truncate_hugepages(inode, offset); |
1da177e4 LT |
462 | return 0; |
463 | } | |
464 | ||
465 | static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr) | |
466 | { | |
467 | struct inode *inode = dentry->d_inode; | |
468 | int error; | |
469 | unsigned int ia_valid = attr->ia_valid; | |
470 | ||
471 | BUG_ON(!inode); | |
472 | ||
473 | error = inode_change_ok(inode, attr); | |
474 | if (error) | |
475 | goto out; | |
476 | ||
477 | if (ia_valid & ATTR_SIZE) { | |
478 | error = -EINVAL; | |
479 | if (!(attr->ia_size & ~HPAGE_MASK)) | |
480 | error = hugetlb_vmtruncate(inode, attr->ia_size); | |
481 | if (error) | |
482 | goto out; | |
483 | attr->ia_valid &= ~ATTR_SIZE; | |
484 | } | |
485 | error = inode_setattr(inode, attr); | |
486 | out: | |
487 | return error; | |
488 | } | |
489 | ||
490 | static struct inode *hugetlbfs_get_inode(struct super_block *sb, uid_t uid, | |
491 | gid_t gid, int mode, dev_t dev) | |
492 | { | |
493 | struct inode *inode; | |
1da177e4 LT |
494 | |
495 | inode = new_inode(sb); | |
496 | if (inode) { | |
497 | struct hugetlbfs_inode_info *info; | |
498 | inode->i_mode = mode; | |
499 | inode->i_uid = uid; | |
500 | inode->i_gid = gid; | |
1da177e4 LT |
501 | inode->i_blocks = 0; |
502 | inode->i_mapping->a_ops = &hugetlbfs_aops; | |
503 | inode->i_mapping->backing_dev_info =&hugetlbfs_backing_dev_info; | |
504 | inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; | |
a43a8c39 | 505 | INIT_LIST_HEAD(&inode->i_mapping->private_list); |
1da177e4 | 506 | info = HUGETLBFS_I(inode); |
71fe804b | 507 | mpol_shared_policy_init(&info->policy, NULL); |
1da177e4 LT |
508 | switch (mode & S_IFMT) { |
509 | default: | |
510 | init_special_inode(inode, mode, dev); | |
511 | break; | |
512 | case S_IFREG: | |
513 | inode->i_op = &hugetlbfs_inode_operations; | |
514 | inode->i_fop = &hugetlbfs_file_operations; | |
515 | break; | |
516 | case S_IFDIR: | |
517 | inode->i_op = &hugetlbfs_dir_inode_operations; | |
518 | inode->i_fop = &simple_dir_operations; | |
519 | ||
520 | /* directory inodes start off with i_nlink == 2 (for "." entry) */ | |
d8c76e6f | 521 | inc_nlink(inode); |
1da177e4 LT |
522 | break; |
523 | case S_IFLNK: | |
524 | inode->i_op = &page_symlink_inode_operations; | |
525 | break; | |
526 | } | |
527 | } | |
528 | return inode; | |
529 | } | |
530 | ||
531 | /* | |
532 | * File creation. Allocate an inode, and we're done.. | |
533 | */ | |
534 | static int hugetlbfs_mknod(struct inode *dir, | |
535 | struct dentry *dentry, int mode, dev_t dev) | |
536 | { | |
537 | struct inode *inode; | |
538 | int error = -ENOSPC; | |
539 | gid_t gid; | |
540 | ||
541 | if (dir->i_mode & S_ISGID) { | |
542 | gid = dir->i_gid; | |
543 | if (S_ISDIR(mode)) | |
544 | mode |= S_ISGID; | |
545 | } else { | |
546 | gid = current->fsgid; | |
547 | } | |
548 | inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, gid, mode, dev); | |
549 | if (inode) { | |
550 | dir->i_ctime = dir->i_mtime = CURRENT_TIME; | |
551 | d_instantiate(dentry, inode); | |
552 | dget(dentry); /* Extra count - pin the dentry in core */ | |
553 | error = 0; | |
554 | } | |
555 | return error; | |
556 | } | |
557 | ||
558 | static int hugetlbfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) | |
559 | { | |
560 | int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0); | |
561 | if (!retval) | |
d8c76e6f | 562 | inc_nlink(dir); |
1da177e4 LT |
563 | return retval; |
564 | } | |
565 | ||
566 | static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd) | |
567 | { | |
568 | return hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0); | |
569 | } | |
570 | ||
571 | static int hugetlbfs_symlink(struct inode *dir, | |
572 | struct dentry *dentry, const char *symname) | |
573 | { | |
574 | struct inode *inode; | |
575 | int error = -ENOSPC; | |
576 | gid_t gid; | |
577 | ||
578 | if (dir->i_mode & S_ISGID) | |
579 | gid = dir->i_gid; | |
580 | else | |
581 | gid = current->fsgid; | |
582 | ||
583 | inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, | |
584 | gid, S_IFLNK|S_IRWXUGO, 0); | |
585 | if (inode) { | |
586 | int l = strlen(symname)+1; | |
587 | error = page_symlink(inode, symname, l); | |
588 | if (!error) { | |
589 | d_instantiate(dentry, inode); | |
590 | dget(dentry); | |
591 | } else | |
592 | iput(inode); | |
593 | } | |
594 | dir->i_ctime = dir->i_mtime = CURRENT_TIME; | |
595 | ||
596 | return error; | |
597 | } | |
598 | ||
599 | /* | |
6649a386 | 600 | * mark the head page dirty |
1da177e4 LT |
601 | */ |
602 | static int hugetlbfs_set_page_dirty(struct page *page) | |
603 | { | |
d85f3385 | 604 | struct page *head = compound_head(page); |
6649a386 KC |
605 | |
606 | SetPageDirty(head); | |
1da177e4 LT |
607 | return 0; |
608 | } | |
609 | ||
726c3342 | 610 | static int hugetlbfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1da177e4 | 611 | { |
726c3342 | 612 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(dentry->d_sb); |
1da177e4 LT |
613 | |
614 | buf->f_type = HUGETLBFS_MAGIC; | |
615 | buf->f_bsize = HPAGE_SIZE; | |
616 | if (sbinfo) { | |
617 | spin_lock(&sbinfo->stat_lock); | |
74a8a65c DG |
618 | /* If no limits set, just report 0 for max/free/used |
619 | * blocks, like simple_statfs() */ | |
620 | if (sbinfo->max_blocks >= 0) { | |
621 | buf->f_blocks = sbinfo->max_blocks; | |
622 | buf->f_bavail = buf->f_bfree = sbinfo->free_blocks; | |
623 | buf->f_files = sbinfo->max_inodes; | |
624 | buf->f_ffree = sbinfo->free_inodes; | |
625 | } | |
1da177e4 LT |
626 | spin_unlock(&sbinfo->stat_lock); |
627 | } | |
628 | buf->f_namelen = NAME_MAX; | |
629 | return 0; | |
630 | } | |
631 | ||
632 | static void hugetlbfs_put_super(struct super_block *sb) | |
633 | { | |
634 | struct hugetlbfs_sb_info *sbi = HUGETLBFS_SB(sb); | |
635 | ||
636 | if (sbi) { | |
637 | sb->s_fs_info = NULL; | |
638 | kfree(sbi); | |
639 | } | |
640 | } | |
641 | ||
96527980 CH |
642 | static inline int hugetlbfs_dec_free_inodes(struct hugetlbfs_sb_info *sbinfo) |
643 | { | |
644 | if (sbinfo->free_inodes >= 0) { | |
645 | spin_lock(&sbinfo->stat_lock); | |
646 | if (unlikely(!sbinfo->free_inodes)) { | |
647 | spin_unlock(&sbinfo->stat_lock); | |
648 | return 0; | |
649 | } | |
650 | sbinfo->free_inodes--; | |
651 | spin_unlock(&sbinfo->stat_lock); | |
652 | } | |
653 | ||
654 | return 1; | |
655 | } | |
656 | ||
657 | static void hugetlbfs_inc_free_inodes(struct hugetlbfs_sb_info *sbinfo) | |
658 | { | |
659 | if (sbinfo->free_inodes >= 0) { | |
660 | spin_lock(&sbinfo->stat_lock); | |
661 | sbinfo->free_inodes++; | |
662 | spin_unlock(&sbinfo->stat_lock); | |
663 | } | |
664 | } | |
665 | ||
666 | ||
e18b890b | 667 | static struct kmem_cache *hugetlbfs_inode_cachep; |
1da177e4 LT |
668 | |
669 | static struct inode *hugetlbfs_alloc_inode(struct super_block *sb) | |
670 | { | |
96527980 | 671 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb); |
1da177e4 LT |
672 | struct hugetlbfs_inode_info *p; |
673 | ||
96527980 CH |
674 | if (unlikely(!hugetlbfs_dec_free_inodes(sbinfo))) |
675 | return NULL; | |
e94b1766 | 676 | p = kmem_cache_alloc(hugetlbfs_inode_cachep, GFP_KERNEL); |
96527980 CH |
677 | if (unlikely(!p)) { |
678 | hugetlbfs_inc_free_inodes(sbinfo); | |
1da177e4 | 679 | return NULL; |
96527980 | 680 | } |
1da177e4 LT |
681 | return &p->vfs_inode; |
682 | } | |
683 | ||
1da177e4 LT |
684 | static void hugetlbfs_destroy_inode(struct inode *inode) |
685 | { | |
96527980 | 686 | hugetlbfs_inc_free_inodes(HUGETLBFS_SB(inode->i_sb)); |
1da177e4 LT |
687 | mpol_free_shared_policy(&HUGETLBFS_I(inode)->policy); |
688 | kmem_cache_free(hugetlbfs_inode_cachep, HUGETLBFS_I(inode)); | |
689 | } | |
690 | ||
f5e54d6e | 691 | static const struct address_space_operations hugetlbfs_aops = { |
1da177e4 | 692 | .readpage = hugetlbfs_readpage, |
800d15a5 NP |
693 | .write_begin = hugetlbfs_write_begin, |
694 | .write_end = hugetlbfs_write_end, | |
1da177e4 LT |
695 | .set_page_dirty = hugetlbfs_set_page_dirty, |
696 | }; | |
697 | ||
96527980 | 698 | |
4ba9b9d0 | 699 | static void init_once(struct kmem_cache *cachep, void *foo) |
96527980 CH |
700 | { |
701 | struct hugetlbfs_inode_info *ei = (struct hugetlbfs_inode_info *)foo; | |
702 | ||
a35afb83 | 703 | inode_init_once(&ei->vfs_inode); |
96527980 CH |
704 | } |
705 | ||
4b6f5d20 | 706 | const struct file_operations hugetlbfs_file_operations = { |
e63e1e5a | 707 | .read = hugetlbfs_read, |
1da177e4 LT |
708 | .mmap = hugetlbfs_file_mmap, |
709 | .fsync = simple_sync_file, | |
710 | .get_unmapped_area = hugetlb_get_unmapped_area, | |
711 | }; | |
712 | ||
92e1d5be | 713 | static const struct inode_operations hugetlbfs_dir_inode_operations = { |
1da177e4 LT |
714 | .create = hugetlbfs_create, |
715 | .lookup = simple_lookup, | |
716 | .link = simple_link, | |
717 | .unlink = simple_unlink, | |
718 | .symlink = hugetlbfs_symlink, | |
719 | .mkdir = hugetlbfs_mkdir, | |
720 | .rmdir = simple_rmdir, | |
721 | .mknod = hugetlbfs_mknod, | |
722 | .rename = simple_rename, | |
723 | .setattr = hugetlbfs_setattr, | |
724 | }; | |
725 | ||
92e1d5be | 726 | static const struct inode_operations hugetlbfs_inode_operations = { |
1da177e4 LT |
727 | .setattr = hugetlbfs_setattr, |
728 | }; | |
729 | ||
ee9b6d61 | 730 | static const struct super_operations hugetlbfs_ops = { |
1da177e4 LT |
731 | .alloc_inode = hugetlbfs_alloc_inode, |
732 | .destroy_inode = hugetlbfs_destroy_inode, | |
733 | .statfs = hugetlbfs_statfs, | |
149f4211 | 734 | .delete_inode = hugetlbfs_delete_inode, |
1da177e4 LT |
735 | .drop_inode = hugetlbfs_drop_inode, |
736 | .put_super = hugetlbfs_put_super, | |
10f19a86 | 737 | .show_options = generic_show_options, |
1da177e4 LT |
738 | }; |
739 | ||
740 | static int | |
741 | hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) | |
742 | { | |
e73a75fa RD |
743 | char *p, *rest; |
744 | substring_t args[MAX_OPT_ARGS]; | |
745 | int option; | |
1da177e4 LT |
746 | |
747 | if (!options) | |
748 | return 0; | |
1da177e4 | 749 | |
e73a75fa RD |
750 | while ((p = strsep(&options, ",")) != NULL) { |
751 | int token; | |
b4c07bce LS |
752 | if (!*p) |
753 | continue; | |
e73a75fa RD |
754 | |
755 | token = match_token(p, tokens, args); | |
756 | switch (token) { | |
757 | case Opt_uid: | |
758 | if (match_int(&args[0], &option)) | |
759 | goto bad_val; | |
760 | pconfig->uid = option; | |
761 | break; | |
762 | ||
763 | case Opt_gid: | |
764 | if (match_int(&args[0], &option)) | |
765 | goto bad_val; | |
766 | pconfig->gid = option; | |
767 | break; | |
768 | ||
769 | case Opt_mode: | |
770 | if (match_octal(&args[0], &option)) | |
771 | goto bad_val; | |
75897d60 | 772 | pconfig->mode = option & 01777U; |
e73a75fa RD |
773 | break; |
774 | ||
775 | case Opt_size: { | |
776 | unsigned long long size; | |
777 | /* memparse() will accept a K/M/G without a digit */ | |
778 | if (!isdigit(*args[0].from)) | |
779 | goto bad_val; | |
780 | size = memparse(args[0].from, &rest); | |
1da177e4 LT |
781 | if (*rest == '%') { |
782 | size <<= HPAGE_SHIFT; | |
783 | size *= max_huge_pages; | |
784 | do_div(size, 100); | |
1da177e4 | 785 | } |
1da177e4 | 786 | pconfig->nr_blocks = (size >> HPAGE_SHIFT); |
e73a75fa RD |
787 | break; |
788 | } | |
1da177e4 | 789 | |
e73a75fa RD |
790 | case Opt_nr_inodes: |
791 | /* memparse() will accept a K/M/G without a digit */ | |
792 | if (!isdigit(*args[0].from)) | |
793 | goto bad_val; | |
794 | pconfig->nr_inodes = memparse(args[0].from, &rest); | |
795 | break; | |
796 | ||
797 | default: | |
b4c07bce LS |
798 | printk(KERN_ERR "hugetlbfs: Bad mount option: \"%s\"\n", |
799 | p); | |
800 | return -EINVAL; | |
e73a75fa RD |
801 | break; |
802 | } | |
1da177e4 LT |
803 | } |
804 | return 0; | |
e73a75fa RD |
805 | |
806 | bad_val: | |
807 | printk(KERN_ERR "hugetlbfs: Bad value '%s' for mount option '%s'\n", | |
808 | args[0].from, p); | |
809 | return 1; | |
1da177e4 LT |
810 | } |
811 | ||
812 | static int | |
813 | hugetlbfs_fill_super(struct super_block *sb, void *data, int silent) | |
814 | { | |
815 | struct inode * inode; | |
816 | struct dentry * root; | |
817 | int ret; | |
818 | struct hugetlbfs_config config; | |
819 | struct hugetlbfs_sb_info *sbinfo; | |
820 | ||
10f19a86 MS |
821 | save_mount_options(sb, data); |
822 | ||
1da177e4 LT |
823 | config.nr_blocks = -1; /* No limit on size by default */ |
824 | config.nr_inodes = -1; /* No limit on number of inodes by default */ | |
825 | config.uid = current->fsuid; | |
826 | config.gid = current->fsgid; | |
827 | config.mode = 0755; | |
828 | ret = hugetlbfs_parse_options(data, &config); | |
1da177e4 LT |
829 | if (ret) |
830 | return ret; | |
831 | ||
832 | sbinfo = kmalloc(sizeof(struct hugetlbfs_sb_info), GFP_KERNEL); | |
833 | if (!sbinfo) | |
834 | return -ENOMEM; | |
835 | sb->s_fs_info = sbinfo; | |
836 | spin_lock_init(&sbinfo->stat_lock); | |
837 | sbinfo->max_blocks = config.nr_blocks; | |
838 | sbinfo->free_blocks = config.nr_blocks; | |
839 | sbinfo->max_inodes = config.nr_inodes; | |
840 | sbinfo->free_inodes = config.nr_inodes; | |
841 | sb->s_maxbytes = MAX_LFS_FILESIZE; | |
842 | sb->s_blocksize = HPAGE_SIZE; | |
843 | sb->s_blocksize_bits = HPAGE_SHIFT; | |
844 | sb->s_magic = HUGETLBFS_MAGIC; | |
845 | sb->s_op = &hugetlbfs_ops; | |
846 | sb->s_time_gran = 1; | |
847 | inode = hugetlbfs_get_inode(sb, config.uid, config.gid, | |
848 | S_IFDIR | config.mode, 0); | |
849 | if (!inode) | |
850 | goto out_free; | |
851 | ||
852 | root = d_alloc_root(inode); | |
853 | if (!root) { | |
854 | iput(inode); | |
855 | goto out_free; | |
856 | } | |
857 | sb->s_root = root; | |
858 | return 0; | |
859 | out_free: | |
860 | kfree(sbinfo); | |
861 | return -ENOMEM; | |
862 | } | |
863 | ||
9a119c05 | 864 | int hugetlb_get_quota(struct address_space *mapping, long delta) |
1da177e4 LT |
865 | { |
866 | int ret = 0; | |
867 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); | |
868 | ||
869 | if (sbinfo->free_blocks > -1) { | |
870 | spin_lock(&sbinfo->stat_lock); | |
9a119c05 AL |
871 | if (sbinfo->free_blocks - delta >= 0) |
872 | sbinfo->free_blocks -= delta; | |
1da177e4 LT |
873 | else |
874 | ret = -ENOMEM; | |
875 | spin_unlock(&sbinfo->stat_lock); | |
876 | } | |
877 | ||
878 | return ret; | |
879 | } | |
880 | ||
9a119c05 | 881 | void hugetlb_put_quota(struct address_space *mapping, long delta) |
1da177e4 LT |
882 | { |
883 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); | |
884 | ||
885 | if (sbinfo->free_blocks > -1) { | |
886 | spin_lock(&sbinfo->stat_lock); | |
9a119c05 | 887 | sbinfo->free_blocks += delta; |
1da177e4 LT |
888 | spin_unlock(&sbinfo->stat_lock); |
889 | } | |
890 | } | |
891 | ||
454e2398 DH |
892 | static int hugetlbfs_get_sb(struct file_system_type *fs_type, |
893 | int flags, const char *dev_name, void *data, struct vfsmount *mnt) | |
1da177e4 | 894 | { |
454e2398 | 895 | return get_sb_nodev(fs_type, flags, data, hugetlbfs_fill_super, mnt); |
1da177e4 LT |
896 | } |
897 | ||
898 | static struct file_system_type hugetlbfs_fs_type = { | |
899 | .name = "hugetlbfs", | |
900 | .get_sb = hugetlbfs_get_sb, | |
901 | .kill_sb = kill_litter_super, | |
902 | }; | |
903 | ||
904 | static struct vfsmount *hugetlbfs_vfsmount; | |
905 | ||
1da177e4 LT |
906 | static int can_do_hugetlb_shm(void) |
907 | { | |
908 | return likely(capable(CAP_IPC_LOCK) || | |
909 | in_group_p(sysctl_hugetlb_shm_group) || | |
910 | can_do_mlock()); | |
911 | } | |
912 | ||
9d66586f | 913 | struct file *hugetlb_file_setup(const char *name, size_t size) |
1da177e4 LT |
914 | { |
915 | int error = -ENOMEM; | |
916 | struct file *file; | |
917 | struct inode *inode; | |
918 | struct dentry *dentry, *root; | |
919 | struct qstr quick_string; | |
1da177e4 | 920 | |
5bc98594 AM |
921 | if (!hugetlbfs_vfsmount) |
922 | return ERR_PTR(-ENOENT); | |
923 | ||
1da177e4 LT |
924 | if (!can_do_hugetlb_shm()) |
925 | return ERR_PTR(-EPERM); | |
926 | ||
1da177e4 LT |
927 | if (!user_shm_lock(size, current->user)) |
928 | return ERR_PTR(-ENOMEM); | |
929 | ||
930 | root = hugetlbfs_vfsmount->mnt_root; | |
9d66586f | 931 | quick_string.name = name; |
1da177e4 LT |
932 | quick_string.len = strlen(quick_string.name); |
933 | quick_string.hash = 0; | |
934 | dentry = d_alloc(root, &quick_string); | |
935 | if (!dentry) | |
936 | goto out_shm_unlock; | |
937 | ||
1da177e4 LT |
938 | error = -ENOSPC; |
939 | inode = hugetlbfs_get_inode(root->d_sb, current->fsuid, | |
940 | current->fsgid, S_IFREG | S_IRWXUGO, 0); | |
941 | if (!inode) | |
ce8d2cdf | 942 | goto out_dentry; |
1da177e4 | 943 | |
b45b5bd6 | 944 | error = -ENOMEM; |
a1e78772 | 945 | if (hugetlb_reserve_pages(inode, 0, size >> HPAGE_SHIFT, NULL)) |
b45b5bd6 DG |
946 | goto out_inode; |
947 | ||
1da177e4 LT |
948 | d_instantiate(dentry, inode); |
949 | inode->i_size = size; | |
950 | inode->i_nlink = 0; | |
ce8d2cdf DH |
951 | |
952 | error = -ENFILE; | |
953 | file = alloc_file(hugetlbfs_vfsmount, dentry, | |
954 | FMODE_WRITE | FMODE_READ, | |
955 | &hugetlbfs_file_operations); | |
956 | if (!file) | |
b4d232e6 | 957 | goto out_dentry; /* inode is already attached */ |
ce8d2cdf | 958 | |
1da177e4 LT |
959 | return file; |
960 | ||
b45b5bd6 DG |
961 | out_inode: |
962 | iput(inode); | |
1da177e4 LT |
963 | out_dentry: |
964 | dput(dentry); | |
965 | out_shm_unlock: | |
966 | user_shm_unlock(size, current->user); | |
967 | return ERR_PTR(error); | |
968 | } | |
969 | ||
970 | static int __init init_hugetlbfs_fs(void) | |
971 | { | |
972 | int error; | |
973 | struct vfsmount *vfsmount; | |
974 | ||
e0bf68dd PZ |
975 | error = bdi_init(&hugetlbfs_backing_dev_info); |
976 | if (error) | |
977 | return error; | |
978 | ||
1da177e4 LT |
979 | hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache", |
980 | sizeof(struct hugetlbfs_inode_info), | |
20c2df83 | 981 | 0, 0, init_once); |
1da177e4 | 982 | if (hugetlbfs_inode_cachep == NULL) |
e0bf68dd | 983 | goto out2; |
1da177e4 LT |
984 | |
985 | error = register_filesystem(&hugetlbfs_fs_type); | |
986 | if (error) | |
987 | goto out; | |
988 | ||
989 | vfsmount = kern_mount(&hugetlbfs_fs_type); | |
990 | ||
991 | if (!IS_ERR(vfsmount)) { | |
992 | hugetlbfs_vfsmount = vfsmount; | |
993 | return 0; | |
994 | } | |
995 | ||
996 | error = PTR_ERR(vfsmount); | |
997 | ||
998 | out: | |
999 | if (error) | |
1000 | kmem_cache_destroy(hugetlbfs_inode_cachep); | |
e0bf68dd PZ |
1001 | out2: |
1002 | bdi_destroy(&hugetlbfs_backing_dev_info); | |
1da177e4 LT |
1003 | return error; |
1004 | } | |
1005 | ||
1006 | static void __exit exit_hugetlbfs_fs(void) | |
1007 | { | |
1008 | kmem_cache_destroy(hugetlbfs_inode_cachep); | |
1009 | unregister_filesystem(&hugetlbfs_fs_type); | |
e0bf68dd | 1010 | bdi_destroy(&hugetlbfs_backing_dev_info); |
1da177e4 LT |
1011 | } |
1012 | ||
1013 | module_init(init_hugetlbfs_fs) | |
1014 | module_exit(exit_hugetlbfs_fs) | |
1015 | ||
1016 | MODULE_LICENSE("GPL"); |