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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; | |
a5516438 | 83 | struct hstate *h = hstate_file(file); |
1da177e4 | 84 | |
68589bc3 | 85 | /* |
dec4ad86 DG |
86 | * vma address alignment (but not the pgoff alignment) has |
87 | * already been checked by prepare_hugepage_range. If you add | |
88 | * any error returns here, do so after setting VM_HUGETLB, so | |
89 | * is_vm_hugetlb_page tests below unmap_region go the right | |
90 | * way when do_mmap_pgoff unwinds (may be important on powerpc | |
91 | * and ia64). | |
68589bc3 HD |
92 | */ |
93 | vma->vm_flags |= VM_HUGETLB | VM_RESERVED; | |
94 | vma->vm_ops = &hugetlb_vm_ops; | |
1da177e4 | 95 | |
a5516438 | 96 | if (vma->vm_pgoff & ~(huge_page_mask(h) >> PAGE_SHIFT)) |
dec4ad86 DG |
97 | return -EINVAL; |
98 | ||
1da177e4 LT |
99 | vma_len = (loff_t)(vma->vm_end - vma->vm_start); |
100 | ||
1b1dcc1b | 101 | mutex_lock(&inode->i_mutex); |
1da177e4 | 102 | file_accessed(file); |
1da177e4 LT |
103 | |
104 | ret = -ENOMEM; | |
105 | len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); | |
1da177e4 | 106 | |
a1e78772 | 107 | if (hugetlb_reserve_pages(inode, |
a5516438 AK |
108 | vma->vm_pgoff >> huge_page_order(h), |
109 | len >> huge_page_shift(h), vma)) | |
a43a8c39 | 110 | goto out; |
b45b5bd6 | 111 | |
4c887265 AL |
112 | ret = 0; |
113 | hugetlb_prefault_arch_hook(vma->vm_mm); | |
b6174df5 | 114 | if (vma->vm_flags & VM_WRITE && inode->i_size < len) |
1da177e4 LT |
115 | inode->i_size = len; |
116 | out: | |
1b1dcc1b | 117 | mutex_unlock(&inode->i_mutex); |
1da177e4 LT |
118 | |
119 | return ret; | |
120 | } | |
121 | ||
122 | /* | |
508034a3 | 123 | * Called under down_write(mmap_sem). |
1da177e4 LT |
124 | */ |
125 | ||
d2ba27e8 | 126 | #ifndef HAVE_ARCH_HUGETLB_UNMAPPED_AREA |
1da177e4 LT |
127 | static unsigned long |
128 | hugetlb_get_unmapped_area(struct file *file, unsigned long addr, | |
129 | unsigned long len, unsigned long pgoff, unsigned long flags) | |
130 | { | |
131 | struct mm_struct *mm = current->mm; | |
132 | struct vm_area_struct *vma; | |
133 | unsigned long start_addr; | |
a5516438 | 134 | struct hstate *h = hstate_file(file); |
1da177e4 | 135 | |
a5516438 | 136 | if (len & ~huge_page_mask(h)) |
1da177e4 LT |
137 | return -EINVAL; |
138 | if (len > TASK_SIZE) | |
139 | return -ENOMEM; | |
140 | ||
036e0856 | 141 | if (flags & MAP_FIXED) { |
a5516438 | 142 | if (prepare_hugepage_range(file, addr, len)) |
036e0856 BH |
143 | return -EINVAL; |
144 | return addr; | |
145 | } | |
146 | ||
1da177e4 | 147 | if (addr) { |
a5516438 | 148 | addr = ALIGN(addr, huge_page_size(h)); |
1da177e4 LT |
149 | vma = find_vma(mm, addr); |
150 | if (TASK_SIZE - len >= addr && | |
151 | (!vma || addr + len <= vma->vm_start)) | |
152 | return addr; | |
153 | } | |
154 | ||
155 | start_addr = mm->free_area_cache; | |
156 | ||
1363c3cd WW |
157 | if (len <= mm->cached_hole_size) |
158 | start_addr = TASK_UNMAPPED_BASE; | |
159 | ||
1da177e4 | 160 | full_search: |
a5516438 | 161 | addr = ALIGN(start_addr, huge_page_size(h)); |
1da177e4 LT |
162 | |
163 | for (vma = find_vma(mm, addr); ; vma = vma->vm_next) { | |
164 | /* At this point: (!vma || addr < vma->vm_end). */ | |
165 | if (TASK_SIZE - len < addr) { | |
166 | /* | |
167 | * Start a new search - just in case we missed | |
168 | * some holes. | |
169 | */ | |
170 | if (start_addr != TASK_UNMAPPED_BASE) { | |
171 | start_addr = TASK_UNMAPPED_BASE; | |
172 | goto full_search; | |
173 | } | |
174 | return -ENOMEM; | |
175 | } | |
176 | ||
177 | if (!vma || addr + len <= vma->vm_start) | |
178 | return addr; | |
a5516438 | 179 | addr = ALIGN(vma->vm_end, huge_page_size(h)); |
1da177e4 LT |
180 | } |
181 | } | |
182 | #endif | |
183 | ||
e63e1e5a BP |
184 | static int |
185 | hugetlbfs_read_actor(struct page *page, unsigned long offset, | |
186 | char __user *buf, unsigned long count, | |
187 | unsigned long size) | |
188 | { | |
189 | char *kaddr; | |
190 | unsigned long left, copied = 0; | |
191 | int i, chunksize; | |
192 | ||
193 | if (size > count) | |
194 | size = count; | |
195 | ||
196 | /* Find which 4k chunk and offset with in that chunk */ | |
197 | i = offset >> PAGE_CACHE_SHIFT; | |
198 | offset = offset & ~PAGE_CACHE_MASK; | |
199 | ||
200 | while (size) { | |
201 | chunksize = PAGE_CACHE_SIZE; | |
202 | if (offset) | |
203 | chunksize -= offset; | |
204 | if (chunksize > size) | |
205 | chunksize = size; | |
206 | kaddr = kmap(&page[i]); | |
207 | left = __copy_to_user(buf, kaddr + offset, chunksize); | |
208 | kunmap(&page[i]); | |
209 | if (left) { | |
210 | copied += (chunksize - left); | |
211 | break; | |
212 | } | |
213 | offset = 0; | |
214 | size -= chunksize; | |
215 | buf += chunksize; | |
216 | copied += chunksize; | |
217 | i++; | |
218 | } | |
219 | return copied ? copied : -EFAULT; | |
220 | } | |
221 | ||
222 | /* | |
223 | * Support for read() - Find the page attached to f_mapping and copy out the | |
224 | * data. Its *very* similar to do_generic_mapping_read(), we can't use that | |
225 | * since it has PAGE_CACHE_SIZE assumptions. | |
226 | */ | |
227 | static ssize_t hugetlbfs_read(struct file *filp, char __user *buf, | |
228 | size_t len, loff_t *ppos) | |
229 | { | |
a5516438 | 230 | struct hstate *h = hstate_file(filp); |
e63e1e5a BP |
231 | struct address_space *mapping = filp->f_mapping; |
232 | struct inode *inode = mapping->host; | |
a5516438 AK |
233 | unsigned long index = *ppos >> huge_page_shift(h); |
234 | unsigned long offset = *ppos & ~huge_page_mask(h); | |
e63e1e5a BP |
235 | unsigned long end_index; |
236 | loff_t isize; | |
237 | ssize_t retval = 0; | |
238 | ||
239 | mutex_lock(&inode->i_mutex); | |
240 | ||
241 | /* validate length */ | |
242 | if (len == 0) | |
243 | goto out; | |
244 | ||
245 | isize = i_size_read(inode); | |
246 | if (!isize) | |
247 | goto out; | |
248 | ||
a5516438 | 249 | end_index = (isize - 1) >> huge_page_shift(h); |
e63e1e5a BP |
250 | for (;;) { |
251 | struct page *page; | |
a5516438 | 252 | unsigned long nr, ret; |
e63e1e5a BP |
253 | |
254 | /* nr is the maximum number of bytes to copy from this page */ | |
a5516438 | 255 | nr = huge_page_size(h); |
e63e1e5a BP |
256 | if (index >= end_index) { |
257 | if (index > end_index) | |
258 | goto out; | |
a5516438 | 259 | nr = ((isize - 1) & ~huge_page_mask(h)) + 1; |
e63e1e5a BP |
260 | if (nr <= offset) { |
261 | goto out; | |
262 | } | |
263 | } | |
264 | nr = nr - offset; | |
265 | ||
266 | /* Find the page */ | |
267 | page = find_get_page(mapping, index); | |
268 | if (unlikely(page == NULL)) { | |
269 | /* | |
270 | * We have a HOLE, zero out the user-buffer for the | |
271 | * length of the hole or request. | |
272 | */ | |
273 | ret = len < nr ? len : nr; | |
274 | if (clear_user(buf, ret)) | |
275 | ret = -EFAULT; | |
276 | } else { | |
277 | /* | |
278 | * We have the page, copy it to user space buffer. | |
279 | */ | |
280 | ret = hugetlbfs_read_actor(page, offset, buf, len, nr); | |
281 | } | |
282 | if (ret < 0) { | |
283 | if (retval == 0) | |
284 | retval = ret; | |
285 | if (page) | |
286 | page_cache_release(page); | |
287 | goto out; | |
288 | } | |
289 | ||
290 | offset += ret; | |
291 | retval += ret; | |
292 | len -= ret; | |
a5516438 AK |
293 | index += offset >> huge_page_shift(h); |
294 | offset &= ~huge_page_mask(h); | |
e63e1e5a BP |
295 | |
296 | if (page) | |
297 | page_cache_release(page); | |
298 | ||
299 | /* short read or no more work */ | |
300 | if ((ret != nr) || (len == 0)) | |
301 | break; | |
302 | } | |
303 | out: | |
a5516438 | 304 | *ppos = ((loff_t)index << huge_page_shift(h)) + offset; |
e63e1e5a BP |
305 | mutex_unlock(&inode->i_mutex); |
306 | return retval; | |
307 | } | |
308 | ||
1da177e4 LT |
309 | /* |
310 | * Read a page. Again trivial. If it didn't already exist | |
311 | * in the page cache, it is zero-filled. | |
312 | */ | |
313 | static int hugetlbfs_readpage(struct file *file, struct page * page) | |
314 | { | |
315 | unlock_page(page); | |
316 | return -EINVAL; | |
317 | } | |
318 | ||
800d15a5 NP |
319 | static int hugetlbfs_write_begin(struct file *file, |
320 | struct address_space *mapping, | |
321 | loff_t pos, unsigned len, unsigned flags, | |
322 | struct page **pagep, void **fsdata) | |
1da177e4 LT |
323 | { |
324 | return -EINVAL; | |
325 | } | |
326 | ||
800d15a5 NP |
327 | static int hugetlbfs_write_end(struct file *file, struct address_space *mapping, |
328 | loff_t pos, unsigned len, unsigned copied, | |
329 | struct page *page, void *fsdata) | |
1da177e4 | 330 | { |
800d15a5 | 331 | BUG(); |
1da177e4 LT |
332 | return -EINVAL; |
333 | } | |
334 | ||
1da177e4 LT |
335 | static void truncate_huge_page(struct page *page) |
336 | { | |
fba2591b | 337 | cancel_dirty_page(page, /* No IO accounting for huge pages? */0); |
1da177e4 LT |
338 | ClearPageUptodate(page); |
339 | remove_from_page_cache(page); | |
340 | put_page(page); | |
341 | } | |
342 | ||
b45b5bd6 | 343 | static void truncate_hugepages(struct inode *inode, loff_t lstart) |
1da177e4 | 344 | { |
a5516438 | 345 | struct hstate *h = hstate_inode(inode); |
b45b5bd6 | 346 | struct address_space *mapping = &inode->i_data; |
a5516438 | 347 | const pgoff_t start = lstart >> huge_page_shift(h); |
1da177e4 LT |
348 | struct pagevec pvec; |
349 | pgoff_t next; | |
a43a8c39 | 350 | int i, freed = 0; |
1da177e4 LT |
351 | |
352 | pagevec_init(&pvec, 0); | |
353 | next = start; | |
354 | while (1) { | |
355 | if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) { | |
356 | if (next == start) | |
357 | break; | |
358 | next = start; | |
359 | continue; | |
360 | } | |
361 | ||
362 | for (i = 0; i < pagevec_count(&pvec); ++i) { | |
363 | struct page *page = pvec.pages[i]; | |
364 | ||
365 | lock_page(page); | |
366 | if (page->index > next) | |
367 | next = page->index; | |
368 | ++next; | |
369 | truncate_huge_page(page); | |
370 | unlock_page(page); | |
a43a8c39 | 371 | freed++; |
1da177e4 LT |
372 | } |
373 | huge_pagevec_release(&pvec); | |
374 | } | |
375 | BUG_ON(!lstart && mapping->nrpages); | |
a43a8c39 | 376 | hugetlb_unreserve_pages(inode, start, freed); |
1da177e4 LT |
377 | } |
378 | ||
379 | static void hugetlbfs_delete_inode(struct inode *inode) | |
380 | { | |
b45b5bd6 | 381 | truncate_hugepages(inode, 0); |
149f4211 CH |
382 | clear_inode(inode); |
383 | } | |
384 | ||
ddc0a51d | 385 | static void hugetlbfs_forget_inode(struct inode *inode) __releases(inode_lock) |
1da177e4 | 386 | { |
0b1533f6 CH |
387 | struct super_block *sb = inode->i_sb; |
388 | ||
389 | if (!hlist_unhashed(&inode->i_hash)) { | |
1c0eeaf5 | 390 | if (!(inode->i_state & (I_DIRTY|I_SYNC))) |
0b1533f6 CH |
391 | list_move(&inode->i_list, &inode_unused); |
392 | inodes_stat.nr_unused++; | |
393 | if (!sb || (sb->s_flags & MS_ACTIVE)) { | |
394 | spin_unlock(&inode_lock); | |
395 | return; | |
396 | } | |
397 | inode->i_state |= I_WILL_FREE; | |
1da177e4 | 398 | spin_unlock(&inode_lock); |
0b1533f6 CH |
399 | /* |
400 | * write_inode_now is a noop as we set BDI_CAP_NO_WRITEBACK | |
401 | * in our backing_dev_info. | |
402 | */ | |
403 | write_inode_now(inode, 1); | |
404 | spin_lock(&inode_lock); | |
405 | inode->i_state &= ~I_WILL_FREE; | |
406 | inodes_stat.nr_unused--; | |
407 | hlist_del_init(&inode->i_hash); | |
1da177e4 | 408 | } |
1da177e4 LT |
409 | list_del_init(&inode->i_list); |
410 | list_del_init(&inode->i_sb_list); | |
411 | inode->i_state |= I_FREEING; | |
412 | inodes_stat.nr_inodes--; | |
413 | spin_unlock(&inode_lock); | |
b45b5bd6 | 414 | truncate_hugepages(inode, 0); |
1da177e4 LT |
415 | clear_inode(inode); |
416 | destroy_inode(inode); | |
417 | } | |
418 | ||
419 | static void hugetlbfs_drop_inode(struct inode *inode) | |
420 | { | |
421 | if (!inode->i_nlink) | |
6b09b9df | 422 | generic_delete_inode(inode); |
1da177e4 LT |
423 | else |
424 | hugetlbfs_forget_inode(inode); | |
425 | } | |
426 | ||
1da177e4 | 427 | static inline void |
856fc295 | 428 | hugetlb_vmtruncate_list(struct prio_tree_root *root, pgoff_t pgoff) |
1da177e4 LT |
429 | { |
430 | struct vm_area_struct *vma; | |
431 | struct prio_tree_iter iter; | |
432 | ||
856fc295 | 433 | vma_prio_tree_foreach(vma, &iter, root, pgoff, ULONG_MAX) { |
1da177e4 LT |
434 | unsigned long v_offset; |
435 | ||
1da177e4 | 436 | /* |
856fc295 HD |
437 | * Can the expression below overflow on 32-bit arches? |
438 | * No, because the prio_tree returns us only those vmas | |
439 | * which overlap the truncated area starting at pgoff, | |
440 | * and no vma on a 32-bit arch can span beyond the 4GB. | |
1da177e4 | 441 | */ |
856fc295 HD |
442 | if (vma->vm_pgoff < pgoff) |
443 | v_offset = (pgoff - vma->vm_pgoff) << PAGE_SHIFT; | |
444 | else | |
1da177e4 LT |
445 | v_offset = 0; |
446 | ||
502717f4 | 447 | __unmap_hugepage_range(vma, |
04f2cbe3 | 448 | vma->vm_start + v_offset, vma->vm_end, NULL); |
1da177e4 LT |
449 | } |
450 | } | |
451 | ||
1da177e4 LT |
452 | static int hugetlb_vmtruncate(struct inode *inode, loff_t offset) |
453 | { | |
856fc295 | 454 | pgoff_t pgoff; |
1da177e4 | 455 | struct address_space *mapping = inode->i_mapping; |
a5516438 | 456 | struct hstate *h = hstate_inode(inode); |
1da177e4 | 457 | |
a5516438 | 458 | BUG_ON(offset & ~huge_page_mask(h)); |
856fc295 | 459 | pgoff = offset >> PAGE_SHIFT; |
1da177e4 | 460 | |
7aa91e10 | 461 | i_size_write(inode, offset); |
1da177e4 LT |
462 | spin_lock(&mapping->i_mmap_lock); |
463 | if (!prio_tree_empty(&mapping->i_mmap)) | |
464 | hugetlb_vmtruncate_list(&mapping->i_mmap, pgoff); | |
465 | spin_unlock(&mapping->i_mmap_lock); | |
b45b5bd6 | 466 | truncate_hugepages(inode, offset); |
1da177e4 LT |
467 | return 0; |
468 | } | |
469 | ||
470 | static int hugetlbfs_setattr(struct dentry *dentry, struct iattr *attr) | |
471 | { | |
472 | struct inode *inode = dentry->d_inode; | |
a5516438 | 473 | struct hstate *h = hstate_inode(inode); |
1da177e4 LT |
474 | int error; |
475 | unsigned int ia_valid = attr->ia_valid; | |
476 | ||
477 | BUG_ON(!inode); | |
478 | ||
479 | error = inode_change_ok(inode, attr); | |
480 | if (error) | |
481 | goto out; | |
482 | ||
483 | if (ia_valid & ATTR_SIZE) { | |
484 | error = -EINVAL; | |
a5516438 | 485 | if (!(attr->ia_size & ~huge_page_mask(h))) |
1da177e4 LT |
486 | error = hugetlb_vmtruncate(inode, attr->ia_size); |
487 | if (error) | |
488 | goto out; | |
489 | attr->ia_valid &= ~ATTR_SIZE; | |
490 | } | |
491 | error = inode_setattr(inode, attr); | |
492 | out: | |
493 | return error; | |
494 | } | |
495 | ||
496 | static struct inode *hugetlbfs_get_inode(struct super_block *sb, uid_t uid, | |
497 | gid_t gid, int mode, dev_t dev) | |
498 | { | |
499 | struct inode *inode; | |
1da177e4 LT |
500 | |
501 | inode = new_inode(sb); | |
502 | if (inode) { | |
503 | struct hugetlbfs_inode_info *info; | |
504 | inode->i_mode = mode; | |
505 | inode->i_uid = uid; | |
506 | inode->i_gid = gid; | |
1da177e4 LT |
507 | inode->i_blocks = 0; |
508 | inode->i_mapping->a_ops = &hugetlbfs_aops; | |
509 | inode->i_mapping->backing_dev_info =&hugetlbfs_backing_dev_info; | |
510 | inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; | |
a43a8c39 | 511 | INIT_LIST_HEAD(&inode->i_mapping->private_list); |
1da177e4 | 512 | info = HUGETLBFS_I(inode); |
71fe804b | 513 | mpol_shared_policy_init(&info->policy, NULL); |
1da177e4 LT |
514 | switch (mode & S_IFMT) { |
515 | default: | |
516 | init_special_inode(inode, mode, dev); | |
517 | break; | |
518 | case S_IFREG: | |
519 | inode->i_op = &hugetlbfs_inode_operations; | |
520 | inode->i_fop = &hugetlbfs_file_operations; | |
521 | break; | |
522 | case S_IFDIR: | |
523 | inode->i_op = &hugetlbfs_dir_inode_operations; | |
524 | inode->i_fop = &simple_dir_operations; | |
525 | ||
526 | /* directory inodes start off with i_nlink == 2 (for "." entry) */ | |
d8c76e6f | 527 | inc_nlink(inode); |
1da177e4 LT |
528 | break; |
529 | case S_IFLNK: | |
530 | inode->i_op = &page_symlink_inode_operations; | |
531 | break; | |
532 | } | |
533 | } | |
534 | return inode; | |
535 | } | |
536 | ||
537 | /* | |
538 | * File creation. Allocate an inode, and we're done.. | |
539 | */ | |
540 | static int hugetlbfs_mknod(struct inode *dir, | |
541 | struct dentry *dentry, int mode, dev_t dev) | |
542 | { | |
543 | struct inode *inode; | |
544 | int error = -ENOSPC; | |
545 | gid_t gid; | |
546 | ||
547 | if (dir->i_mode & S_ISGID) { | |
548 | gid = dir->i_gid; | |
549 | if (S_ISDIR(mode)) | |
550 | mode |= S_ISGID; | |
551 | } else { | |
552 | gid = current->fsgid; | |
553 | } | |
554 | inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, gid, mode, dev); | |
555 | if (inode) { | |
556 | dir->i_ctime = dir->i_mtime = CURRENT_TIME; | |
557 | d_instantiate(dentry, inode); | |
558 | dget(dentry); /* Extra count - pin the dentry in core */ | |
559 | error = 0; | |
560 | } | |
561 | return error; | |
562 | } | |
563 | ||
564 | static int hugetlbfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) | |
565 | { | |
566 | int retval = hugetlbfs_mknod(dir, dentry, mode | S_IFDIR, 0); | |
567 | if (!retval) | |
d8c76e6f | 568 | inc_nlink(dir); |
1da177e4 LT |
569 | return retval; |
570 | } | |
571 | ||
572 | static int hugetlbfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd) | |
573 | { | |
574 | return hugetlbfs_mknod(dir, dentry, mode | S_IFREG, 0); | |
575 | } | |
576 | ||
577 | static int hugetlbfs_symlink(struct inode *dir, | |
578 | struct dentry *dentry, const char *symname) | |
579 | { | |
580 | struct inode *inode; | |
581 | int error = -ENOSPC; | |
582 | gid_t gid; | |
583 | ||
584 | if (dir->i_mode & S_ISGID) | |
585 | gid = dir->i_gid; | |
586 | else | |
587 | gid = current->fsgid; | |
588 | ||
589 | inode = hugetlbfs_get_inode(dir->i_sb, current->fsuid, | |
590 | gid, S_IFLNK|S_IRWXUGO, 0); | |
591 | if (inode) { | |
592 | int l = strlen(symname)+1; | |
593 | error = page_symlink(inode, symname, l); | |
594 | if (!error) { | |
595 | d_instantiate(dentry, inode); | |
596 | dget(dentry); | |
597 | } else | |
598 | iput(inode); | |
599 | } | |
600 | dir->i_ctime = dir->i_mtime = CURRENT_TIME; | |
601 | ||
602 | return error; | |
603 | } | |
604 | ||
605 | /* | |
6649a386 | 606 | * mark the head page dirty |
1da177e4 LT |
607 | */ |
608 | static int hugetlbfs_set_page_dirty(struct page *page) | |
609 | { | |
d85f3385 | 610 | struct page *head = compound_head(page); |
6649a386 KC |
611 | |
612 | SetPageDirty(head); | |
1da177e4 LT |
613 | return 0; |
614 | } | |
615 | ||
726c3342 | 616 | static int hugetlbfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1da177e4 | 617 | { |
726c3342 | 618 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(dentry->d_sb); |
a5516438 | 619 | struct hstate *h = hstate_inode(dentry->d_inode); |
1da177e4 LT |
620 | |
621 | buf->f_type = HUGETLBFS_MAGIC; | |
a5516438 | 622 | buf->f_bsize = huge_page_size(h); |
1da177e4 LT |
623 | if (sbinfo) { |
624 | spin_lock(&sbinfo->stat_lock); | |
74a8a65c DG |
625 | /* If no limits set, just report 0 for max/free/used |
626 | * blocks, like simple_statfs() */ | |
627 | if (sbinfo->max_blocks >= 0) { | |
628 | buf->f_blocks = sbinfo->max_blocks; | |
629 | buf->f_bavail = buf->f_bfree = sbinfo->free_blocks; | |
630 | buf->f_files = sbinfo->max_inodes; | |
631 | buf->f_ffree = sbinfo->free_inodes; | |
632 | } | |
1da177e4 LT |
633 | spin_unlock(&sbinfo->stat_lock); |
634 | } | |
635 | buf->f_namelen = NAME_MAX; | |
636 | return 0; | |
637 | } | |
638 | ||
639 | static void hugetlbfs_put_super(struct super_block *sb) | |
640 | { | |
641 | struct hugetlbfs_sb_info *sbi = HUGETLBFS_SB(sb); | |
642 | ||
643 | if (sbi) { | |
644 | sb->s_fs_info = NULL; | |
645 | kfree(sbi); | |
646 | } | |
647 | } | |
648 | ||
96527980 CH |
649 | static inline int hugetlbfs_dec_free_inodes(struct hugetlbfs_sb_info *sbinfo) |
650 | { | |
651 | if (sbinfo->free_inodes >= 0) { | |
652 | spin_lock(&sbinfo->stat_lock); | |
653 | if (unlikely(!sbinfo->free_inodes)) { | |
654 | spin_unlock(&sbinfo->stat_lock); | |
655 | return 0; | |
656 | } | |
657 | sbinfo->free_inodes--; | |
658 | spin_unlock(&sbinfo->stat_lock); | |
659 | } | |
660 | ||
661 | return 1; | |
662 | } | |
663 | ||
664 | static void hugetlbfs_inc_free_inodes(struct hugetlbfs_sb_info *sbinfo) | |
665 | { | |
666 | if (sbinfo->free_inodes >= 0) { | |
667 | spin_lock(&sbinfo->stat_lock); | |
668 | sbinfo->free_inodes++; | |
669 | spin_unlock(&sbinfo->stat_lock); | |
670 | } | |
671 | } | |
672 | ||
673 | ||
e18b890b | 674 | static struct kmem_cache *hugetlbfs_inode_cachep; |
1da177e4 LT |
675 | |
676 | static struct inode *hugetlbfs_alloc_inode(struct super_block *sb) | |
677 | { | |
96527980 | 678 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(sb); |
1da177e4 LT |
679 | struct hugetlbfs_inode_info *p; |
680 | ||
96527980 CH |
681 | if (unlikely(!hugetlbfs_dec_free_inodes(sbinfo))) |
682 | return NULL; | |
e94b1766 | 683 | p = kmem_cache_alloc(hugetlbfs_inode_cachep, GFP_KERNEL); |
96527980 CH |
684 | if (unlikely(!p)) { |
685 | hugetlbfs_inc_free_inodes(sbinfo); | |
1da177e4 | 686 | return NULL; |
96527980 | 687 | } |
1da177e4 LT |
688 | return &p->vfs_inode; |
689 | } | |
690 | ||
1da177e4 LT |
691 | static void hugetlbfs_destroy_inode(struct inode *inode) |
692 | { | |
96527980 | 693 | hugetlbfs_inc_free_inodes(HUGETLBFS_SB(inode->i_sb)); |
1da177e4 LT |
694 | mpol_free_shared_policy(&HUGETLBFS_I(inode)->policy); |
695 | kmem_cache_free(hugetlbfs_inode_cachep, HUGETLBFS_I(inode)); | |
696 | } | |
697 | ||
f5e54d6e | 698 | static const struct address_space_operations hugetlbfs_aops = { |
1da177e4 | 699 | .readpage = hugetlbfs_readpage, |
800d15a5 NP |
700 | .write_begin = hugetlbfs_write_begin, |
701 | .write_end = hugetlbfs_write_end, | |
1da177e4 LT |
702 | .set_page_dirty = hugetlbfs_set_page_dirty, |
703 | }; | |
704 | ||
96527980 | 705 | |
4ba9b9d0 | 706 | static void init_once(struct kmem_cache *cachep, void *foo) |
96527980 CH |
707 | { |
708 | struct hugetlbfs_inode_info *ei = (struct hugetlbfs_inode_info *)foo; | |
709 | ||
a35afb83 | 710 | inode_init_once(&ei->vfs_inode); |
96527980 CH |
711 | } |
712 | ||
4b6f5d20 | 713 | const struct file_operations hugetlbfs_file_operations = { |
e63e1e5a | 714 | .read = hugetlbfs_read, |
1da177e4 LT |
715 | .mmap = hugetlbfs_file_mmap, |
716 | .fsync = simple_sync_file, | |
717 | .get_unmapped_area = hugetlb_get_unmapped_area, | |
718 | }; | |
719 | ||
92e1d5be | 720 | static const struct inode_operations hugetlbfs_dir_inode_operations = { |
1da177e4 LT |
721 | .create = hugetlbfs_create, |
722 | .lookup = simple_lookup, | |
723 | .link = simple_link, | |
724 | .unlink = simple_unlink, | |
725 | .symlink = hugetlbfs_symlink, | |
726 | .mkdir = hugetlbfs_mkdir, | |
727 | .rmdir = simple_rmdir, | |
728 | .mknod = hugetlbfs_mknod, | |
729 | .rename = simple_rename, | |
730 | .setattr = hugetlbfs_setattr, | |
731 | }; | |
732 | ||
92e1d5be | 733 | static const struct inode_operations hugetlbfs_inode_operations = { |
1da177e4 LT |
734 | .setattr = hugetlbfs_setattr, |
735 | }; | |
736 | ||
ee9b6d61 | 737 | static const struct super_operations hugetlbfs_ops = { |
1da177e4 LT |
738 | .alloc_inode = hugetlbfs_alloc_inode, |
739 | .destroy_inode = hugetlbfs_destroy_inode, | |
740 | .statfs = hugetlbfs_statfs, | |
149f4211 | 741 | .delete_inode = hugetlbfs_delete_inode, |
1da177e4 LT |
742 | .drop_inode = hugetlbfs_drop_inode, |
743 | .put_super = hugetlbfs_put_super, | |
10f19a86 | 744 | .show_options = generic_show_options, |
1da177e4 LT |
745 | }; |
746 | ||
747 | static int | |
748 | hugetlbfs_parse_options(char *options, struct hugetlbfs_config *pconfig) | |
749 | { | |
e73a75fa RD |
750 | char *p, *rest; |
751 | substring_t args[MAX_OPT_ARGS]; | |
752 | int option; | |
1da177e4 LT |
753 | |
754 | if (!options) | |
755 | return 0; | |
1da177e4 | 756 | |
e73a75fa RD |
757 | while ((p = strsep(&options, ",")) != NULL) { |
758 | int token; | |
b4c07bce LS |
759 | if (!*p) |
760 | continue; | |
e73a75fa RD |
761 | |
762 | token = match_token(p, tokens, args); | |
763 | switch (token) { | |
764 | case Opt_uid: | |
765 | if (match_int(&args[0], &option)) | |
766 | goto bad_val; | |
767 | pconfig->uid = option; | |
768 | break; | |
769 | ||
770 | case Opt_gid: | |
771 | if (match_int(&args[0], &option)) | |
772 | goto bad_val; | |
773 | pconfig->gid = option; | |
774 | break; | |
775 | ||
776 | case Opt_mode: | |
777 | if (match_octal(&args[0], &option)) | |
778 | goto bad_val; | |
75897d60 | 779 | pconfig->mode = option & 01777U; |
e73a75fa RD |
780 | break; |
781 | ||
782 | case Opt_size: { | |
783 | unsigned long long size; | |
784 | /* memparse() will accept a K/M/G without a digit */ | |
785 | if (!isdigit(*args[0].from)) | |
786 | goto bad_val; | |
787 | size = memparse(args[0].from, &rest); | |
1da177e4 LT |
788 | if (*rest == '%') { |
789 | size <<= HPAGE_SHIFT; | |
790 | size *= max_huge_pages; | |
791 | do_div(size, 100); | |
1da177e4 | 792 | } |
1da177e4 | 793 | pconfig->nr_blocks = (size >> HPAGE_SHIFT); |
e73a75fa RD |
794 | break; |
795 | } | |
1da177e4 | 796 | |
e73a75fa RD |
797 | case Opt_nr_inodes: |
798 | /* memparse() will accept a K/M/G without a digit */ | |
799 | if (!isdigit(*args[0].from)) | |
800 | goto bad_val; | |
801 | pconfig->nr_inodes = memparse(args[0].from, &rest); | |
802 | break; | |
803 | ||
804 | default: | |
b4c07bce LS |
805 | printk(KERN_ERR "hugetlbfs: Bad mount option: \"%s\"\n", |
806 | p); | |
807 | return -EINVAL; | |
e73a75fa RD |
808 | break; |
809 | } | |
1da177e4 LT |
810 | } |
811 | return 0; | |
e73a75fa RD |
812 | |
813 | bad_val: | |
814 | printk(KERN_ERR "hugetlbfs: Bad value '%s' for mount option '%s'\n", | |
815 | args[0].from, p); | |
816 | return 1; | |
1da177e4 LT |
817 | } |
818 | ||
819 | static int | |
820 | hugetlbfs_fill_super(struct super_block *sb, void *data, int silent) | |
821 | { | |
822 | struct inode * inode; | |
823 | struct dentry * root; | |
824 | int ret; | |
825 | struct hugetlbfs_config config; | |
826 | struct hugetlbfs_sb_info *sbinfo; | |
827 | ||
10f19a86 MS |
828 | save_mount_options(sb, data); |
829 | ||
1da177e4 LT |
830 | config.nr_blocks = -1; /* No limit on size by default */ |
831 | config.nr_inodes = -1; /* No limit on number of inodes by default */ | |
832 | config.uid = current->fsuid; | |
833 | config.gid = current->fsgid; | |
834 | config.mode = 0755; | |
835 | ret = hugetlbfs_parse_options(data, &config); | |
1da177e4 LT |
836 | if (ret) |
837 | return ret; | |
838 | ||
839 | sbinfo = kmalloc(sizeof(struct hugetlbfs_sb_info), GFP_KERNEL); | |
840 | if (!sbinfo) | |
841 | return -ENOMEM; | |
842 | sb->s_fs_info = sbinfo; | |
843 | spin_lock_init(&sbinfo->stat_lock); | |
844 | sbinfo->max_blocks = config.nr_blocks; | |
845 | sbinfo->free_blocks = config.nr_blocks; | |
846 | sbinfo->max_inodes = config.nr_inodes; | |
847 | sbinfo->free_inodes = config.nr_inodes; | |
848 | sb->s_maxbytes = MAX_LFS_FILESIZE; | |
849 | sb->s_blocksize = HPAGE_SIZE; | |
850 | sb->s_blocksize_bits = HPAGE_SHIFT; | |
851 | sb->s_magic = HUGETLBFS_MAGIC; | |
852 | sb->s_op = &hugetlbfs_ops; | |
853 | sb->s_time_gran = 1; | |
854 | inode = hugetlbfs_get_inode(sb, config.uid, config.gid, | |
855 | S_IFDIR | config.mode, 0); | |
856 | if (!inode) | |
857 | goto out_free; | |
858 | ||
859 | root = d_alloc_root(inode); | |
860 | if (!root) { | |
861 | iput(inode); | |
862 | goto out_free; | |
863 | } | |
864 | sb->s_root = root; | |
865 | return 0; | |
866 | out_free: | |
867 | kfree(sbinfo); | |
868 | return -ENOMEM; | |
869 | } | |
870 | ||
9a119c05 | 871 | int hugetlb_get_quota(struct address_space *mapping, long delta) |
1da177e4 LT |
872 | { |
873 | int ret = 0; | |
874 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); | |
875 | ||
876 | if (sbinfo->free_blocks > -1) { | |
877 | spin_lock(&sbinfo->stat_lock); | |
9a119c05 AL |
878 | if (sbinfo->free_blocks - delta >= 0) |
879 | sbinfo->free_blocks -= delta; | |
1da177e4 LT |
880 | else |
881 | ret = -ENOMEM; | |
882 | spin_unlock(&sbinfo->stat_lock); | |
883 | } | |
884 | ||
885 | return ret; | |
886 | } | |
887 | ||
9a119c05 | 888 | void hugetlb_put_quota(struct address_space *mapping, long delta) |
1da177e4 LT |
889 | { |
890 | struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(mapping->host->i_sb); | |
891 | ||
892 | if (sbinfo->free_blocks > -1) { | |
893 | spin_lock(&sbinfo->stat_lock); | |
9a119c05 | 894 | sbinfo->free_blocks += delta; |
1da177e4 LT |
895 | spin_unlock(&sbinfo->stat_lock); |
896 | } | |
897 | } | |
898 | ||
454e2398 DH |
899 | static int hugetlbfs_get_sb(struct file_system_type *fs_type, |
900 | int flags, const char *dev_name, void *data, struct vfsmount *mnt) | |
1da177e4 | 901 | { |
454e2398 | 902 | return get_sb_nodev(fs_type, flags, data, hugetlbfs_fill_super, mnt); |
1da177e4 LT |
903 | } |
904 | ||
905 | static struct file_system_type hugetlbfs_fs_type = { | |
906 | .name = "hugetlbfs", | |
907 | .get_sb = hugetlbfs_get_sb, | |
908 | .kill_sb = kill_litter_super, | |
909 | }; | |
910 | ||
911 | static struct vfsmount *hugetlbfs_vfsmount; | |
912 | ||
1da177e4 LT |
913 | static int can_do_hugetlb_shm(void) |
914 | { | |
915 | return likely(capable(CAP_IPC_LOCK) || | |
916 | in_group_p(sysctl_hugetlb_shm_group) || | |
917 | can_do_mlock()); | |
918 | } | |
919 | ||
9d66586f | 920 | struct file *hugetlb_file_setup(const char *name, size_t size) |
1da177e4 LT |
921 | { |
922 | int error = -ENOMEM; | |
923 | struct file *file; | |
924 | struct inode *inode; | |
925 | struct dentry *dentry, *root; | |
926 | struct qstr quick_string; | |
1da177e4 | 927 | |
5bc98594 AM |
928 | if (!hugetlbfs_vfsmount) |
929 | return ERR_PTR(-ENOENT); | |
930 | ||
1da177e4 LT |
931 | if (!can_do_hugetlb_shm()) |
932 | return ERR_PTR(-EPERM); | |
933 | ||
1da177e4 LT |
934 | if (!user_shm_lock(size, current->user)) |
935 | return ERR_PTR(-ENOMEM); | |
936 | ||
937 | root = hugetlbfs_vfsmount->mnt_root; | |
9d66586f | 938 | quick_string.name = name; |
1da177e4 LT |
939 | quick_string.len = strlen(quick_string.name); |
940 | quick_string.hash = 0; | |
941 | dentry = d_alloc(root, &quick_string); | |
942 | if (!dentry) | |
943 | goto out_shm_unlock; | |
944 | ||
1da177e4 LT |
945 | error = -ENOSPC; |
946 | inode = hugetlbfs_get_inode(root->d_sb, current->fsuid, | |
947 | current->fsgid, S_IFREG | S_IRWXUGO, 0); | |
948 | if (!inode) | |
ce8d2cdf | 949 | goto out_dentry; |
1da177e4 | 950 | |
b45b5bd6 | 951 | error = -ENOMEM; |
a5516438 AK |
952 | if (hugetlb_reserve_pages(inode, 0, |
953 | size >> huge_page_shift(hstate_inode(inode)), NULL)) | |
b45b5bd6 DG |
954 | goto out_inode; |
955 | ||
1da177e4 LT |
956 | d_instantiate(dentry, inode); |
957 | inode->i_size = size; | |
958 | inode->i_nlink = 0; | |
ce8d2cdf DH |
959 | |
960 | error = -ENFILE; | |
961 | file = alloc_file(hugetlbfs_vfsmount, dentry, | |
962 | FMODE_WRITE | FMODE_READ, | |
963 | &hugetlbfs_file_operations); | |
964 | if (!file) | |
b4d232e6 | 965 | goto out_dentry; /* inode is already attached */ |
ce8d2cdf | 966 | |
1da177e4 LT |
967 | return file; |
968 | ||
b45b5bd6 DG |
969 | out_inode: |
970 | iput(inode); | |
1da177e4 LT |
971 | out_dentry: |
972 | dput(dentry); | |
973 | out_shm_unlock: | |
974 | user_shm_unlock(size, current->user); | |
975 | return ERR_PTR(error); | |
976 | } | |
977 | ||
978 | static int __init init_hugetlbfs_fs(void) | |
979 | { | |
980 | int error; | |
981 | struct vfsmount *vfsmount; | |
982 | ||
e0bf68dd PZ |
983 | error = bdi_init(&hugetlbfs_backing_dev_info); |
984 | if (error) | |
985 | return error; | |
986 | ||
1da177e4 LT |
987 | hugetlbfs_inode_cachep = kmem_cache_create("hugetlbfs_inode_cache", |
988 | sizeof(struct hugetlbfs_inode_info), | |
20c2df83 | 989 | 0, 0, init_once); |
1da177e4 | 990 | if (hugetlbfs_inode_cachep == NULL) |
e0bf68dd | 991 | goto out2; |
1da177e4 LT |
992 | |
993 | error = register_filesystem(&hugetlbfs_fs_type); | |
994 | if (error) | |
995 | goto out; | |
996 | ||
997 | vfsmount = kern_mount(&hugetlbfs_fs_type); | |
998 | ||
999 | if (!IS_ERR(vfsmount)) { | |
1000 | hugetlbfs_vfsmount = vfsmount; | |
1001 | return 0; | |
1002 | } | |
1003 | ||
1004 | error = PTR_ERR(vfsmount); | |
1005 | ||
1006 | out: | |
1007 | if (error) | |
1008 | kmem_cache_destroy(hugetlbfs_inode_cachep); | |
e0bf68dd PZ |
1009 | out2: |
1010 | bdi_destroy(&hugetlbfs_backing_dev_info); | |
1da177e4 LT |
1011 | return error; |
1012 | } | |
1013 | ||
1014 | static void __exit exit_hugetlbfs_fs(void) | |
1015 | { | |
1016 | kmem_cache_destroy(hugetlbfs_inode_cachep); | |
1017 | unregister_filesystem(&hugetlbfs_fs_type); | |
e0bf68dd | 1018 | bdi_destroy(&hugetlbfs_backing_dev_info); |
1da177e4 LT |
1019 | } |
1020 | ||
1021 | module_init(init_hugetlbfs_fs) | |
1022 | module_exit(exit_hugetlbfs_fs) | |
1023 | ||
1024 | MODULE_LICENSE("GPL"); |