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1// SPDX-License-Identifier: GPL-2.0-or-later
2/* AFS filesystem file handling
3 *
4 * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/fs.h>
12#include <linux/pagemap.h>
13#include <linux/writeback.h>
14#include <linux/gfp.h>
15#include <linux/task_io_accounting_ops.h>
16#include <linux/mm.h>
17#include <linux/swap.h>
18#include <linux/netfs.h>
19#include <trace/events/netfs.h>
20#include "internal.h"
21
22static int afs_file_mmap(struct file *file, struct vm_area_struct *vma);
23static int afs_symlink_read_folio(struct file *file, struct folio *folio);
24
25static ssize_t afs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter);
26static ssize_t afs_file_splice_read(struct file *in, loff_t *ppos,
27 struct pipe_inode_info *pipe,
28 size_t len, unsigned int flags);
29static void afs_vm_open(struct vm_area_struct *area);
30static void afs_vm_close(struct vm_area_struct *area);
31static vm_fault_t afs_vm_map_pages(struct vm_fault *vmf, pgoff_t start_pgoff, pgoff_t end_pgoff);
32
33const struct file_operations afs_file_operations = {
34 .open = afs_open,
35 .release = afs_release,
36 .llseek = generic_file_llseek,
37 .read_iter = afs_file_read_iter,
38 .write_iter = netfs_file_write_iter,
39 .mmap = afs_file_mmap,
40 .splice_read = afs_file_splice_read,
41 .splice_write = iter_file_splice_write,
42 .fsync = afs_fsync,
43 .lock = afs_lock,
44 .flock = afs_flock,
45};
46
47const struct inode_operations afs_file_inode_operations = {
48 .getattr = afs_getattr,
49 .setattr = afs_setattr,
50 .permission = afs_permission,
51};
52
53const struct address_space_operations afs_file_aops = {
54 .direct_IO = noop_direct_IO,
55 .read_folio = netfs_read_folio,
56 .readahead = netfs_readahead,
57 .dirty_folio = netfs_dirty_folio,
58 .release_folio = netfs_release_folio,
59 .invalidate_folio = netfs_invalidate_folio,
60 .migrate_folio = filemap_migrate_folio,
61 .writepages = afs_writepages,
62};
63
64const struct address_space_operations afs_symlink_aops = {
65 .read_folio = afs_symlink_read_folio,
66 .release_folio = netfs_release_folio,
67 .invalidate_folio = netfs_invalidate_folio,
68 .migrate_folio = filemap_migrate_folio,
69};
70
71static const struct vm_operations_struct afs_vm_ops = {
72 .open = afs_vm_open,
73 .close = afs_vm_close,
74 .fault = filemap_fault,
75 .map_pages = afs_vm_map_pages,
76 .page_mkwrite = afs_page_mkwrite,
77};
78
79/*
80 * Discard a pin on a writeback key.
81 */
82void afs_put_wb_key(struct afs_wb_key *wbk)
83{
84 if (wbk && refcount_dec_and_test(&wbk->usage)) {
85 key_put(wbk->key);
86 kfree(wbk);
87 }
88}
89
90/*
91 * Cache key for writeback.
92 */
93int afs_cache_wb_key(struct afs_vnode *vnode, struct afs_file *af)
94{
95 struct afs_wb_key *wbk, *p;
96
97 wbk = kzalloc(sizeof(struct afs_wb_key), GFP_KERNEL);
98 if (!wbk)
99 return -ENOMEM;
100 refcount_set(&wbk->usage, 2);
101 wbk->key = af->key;
102
103 spin_lock(&vnode->wb_lock);
104 list_for_each_entry(p, &vnode->wb_keys, vnode_link) {
105 if (p->key == wbk->key)
106 goto found;
107 }
108
109 key_get(wbk->key);
110 list_add_tail(&wbk->vnode_link, &vnode->wb_keys);
111 spin_unlock(&vnode->wb_lock);
112 af->wb = wbk;
113 return 0;
114
115found:
116 refcount_inc(&p->usage);
117 spin_unlock(&vnode->wb_lock);
118 af->wb = p;
119 kfree(wbk);
120 return 0;
121}
122
123/*
124 * open an AFS file or directory and attach a key to it
125 */
126int afs_open(struct inode *inode, struct file *file)
127{
128 struct afs_vnode *vnode = AFS_FS_I(inode);
129 struct afs_file *af;
130 struct key *key;
131 int ret;
132
133 _enter("{%llx:%llu},", vnode->fid.vid, vnode->fid.vnode);
134
135 key = afs_request_key(vnode->volume->cell);
136 if (IS_ERR(key)) {
137 ret = PTR_ERR(key);
138 goto error;
139 }
140
141 af = kzalloc(sizeof(*af), GFP_KERNEL);
142 if (!af) {
143 ret = -ENOMEM;
144 goto error_key;
145 }
146 af->key = key;
147
148 ret = afs_validate(vnode, key);
149 if (ret < 0)
150 goto error_af;
151
152 if (file->f_mode & FMODE_WRITE) {
153 ret = afs_cache_wb_key(vnode, af);
154 if (ret < 0)
155 goto error_af;
156 }
157
158 if (file->f_flags & O_TRUNC)
159 set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags);
160
161 fscache_use_cookie(afs_vnode_cache(vnode), file->f_mode & FMODE_WRITE);
162
163 file->private_data = af;
164 _leave(" = 0");
165 return 0;
166
167error_af:
168 kfree(af);
169error_key:
170 key_put(key);
171error:
172 _leave(" = %d", ret);
173 return ret;
174}
175
176/*
177 * release an AFS file or directory and discard its key
178 */
179int afs_release(struct inode *inode, struct file *file)
180{
181 struct afs_vnode_cache_aux aux;
182 struct afs_vnode *vnode = AFS_FS_I(inode);
183 struct afs_file *af = file->private_data;
184 loff_t i_size;
185 int ret = 0;
186
187 _enter("{%llx:%llu},", vnode->fid.vid, vnode->fid.vnode);
188
189 if ((file->f_mode & FMODE_WRITE))
190 ret = vfs_fsync(file, 0);
191
192 file->private_data = NULL;
193 if (af->wb)
194 afs_put_wb_key(af->wb);
195
196 if ((file->f_mode & FMODE_WRITE)) {
197 i_size = i_size_read(&vnode->netfs.inode);
198 afs_set_cache_aux(vnode, &aux);
199 fscache_unuse_cookie(afs_vnode_cache(vnode), &aux, &i_size);
200 } else {
201 fscache_unuse_cookie(afs_vnode_cache(vnode), NULL, NULL);
202 }
203
204 key_put(af->key);
205 kfree(af);
206 afs_prune_wb_keys(vnode);
207 _leave(" = %d", ret);
208 return ret;
209}
210
211/*
212 * Allocate a new read record.
213 */
214struct afs_read *afs_alloc_read(gfp_t gfp)
215{
216 struct afs_read *req;
217
218 req = kzalloc(sizeof(struct afs_read), gfp);
219 if (req)
220 refcount_set(&req->usage, 1);
221
222 return req;
223}
224
225/*
226 * Dispose of a ref to a read record.
227 */
228void afs_put_read(struct afs_read *req)
229{
230 if (refcount_dec_and_test(&req->usage)) {
231 if (req->cleanup)
232 req->cleanup(req);
233 key_put(req->key);
234 kfree(req);
235 }
236}
237
238static void afs_fetch_data_notify(struct afs_operation *op)
239{
240 struct afs_read *req = op->fetch.req;
241 struct netfs_io_subrequest *subreq = req->subreq;
242 int error = afs_op_error(op);
243
244 req->error = error;
245 if (subreq) {
246 subreq->rreq->i_size = req->file_size;
247 if (req->pos + req->actual_len >= req->file_size)
248 __set_bit(NETFS_SREQ_HIT_EOF, &subreq->flags);
249 netfs_read_subreq_terminated(subreq, error, false);
250 req->subreq = NULL;
251 } else if (req->done) {
252 req->done(req);
253 }
254}
255
256static void afs_fetch_data_success(struct afs_operation *op)
257{
258 struct afs_vnode *vnode = op->file[0].vnode;
259
260 _enter("op=%08x", op->debug_id);
261 afs_vnode_commit_status(op, &op->file[0]);
262 afs_stat_v(vnode, n_fetches);
263 atomic_long_add(op->fetch.req->actual_len, &op->net->n_fetch_bytes);
264 afs_fetch_data_notify(op);
265}
266
267static void afs_fetch_data_aborted(struct afs_operation *op)
268{
269 afs_check_for_remote_deletion(op);
270 afs_fetch_data_notify(op);
271}
272
273static void afs_fetch_data_put(struct afs_operation *op)
274{
275 op->fetch.req->error = afs_op_error(op);
276 afs_put_read(op->fetch.req);
277}
278
279static const struct afs_operation_ops afs_fetch_data_operation = {
280 .issue_afs_rpc = afs_fs_fetch_data,
281 .issue_yfs_rpc = yfs_fs_fetch_data,
282 .success = afs_fetch_data_success,
283 .aborted = afs_fetch_data_aborted,
284 .failed = afs_fetch_data_notify,
285 .put = afs_fetch_data_put,
286};
287
288/*
289 * Fetch file data from the volume.
290 */
291int afs_fetch_data(struct afs_vnode *vnode, struct afs_read *req)
292{
293 struct afs_operation *op;
294
295 _enter("%s{%llx:%llu.%u},%x,,,",
296 vnode->volume->name,
297 vnode->fid.vid,
298 vnode->fid.vnode,
299 vnode->fid.unique,
300 key_serial(req->key));
301
302 op = afs_alloc_operation(req->key, vnode->volume);
303 if (IS_ERR(op)) {
304 if (req->subreq)
305 netfs_read_subreq_terminated(req->subreq, PTR_ERR(op), false);
306 return PTR_ERR(op);
307 }
308
309 afs_op_set_vnode(op, 0, vnode);
310
311 op->fetch.req = afs_get_read(req);
312 op->ops = &afs_fetch_data_operation;
313 return afs_do_sync_operation(op);
314}
315
316static void afs_read_worker(struct work_struct *work)
317{
318 struct netfs_io_subrequest *subreq = container_of(work, struct netfs_io_subrequest, work);
319 struct afs_vnode *vnode = AFS_FS_I(subreq->rreq->inode);
320 struct afs_read *fsreq;
321
322 fsreq = afs_alloc_read(GFP_NOFS);
323 if (!fsreq)
324 return netfs_read_subreq_terminated(subreq, -ENOMEM, false);
325
326 fsreq->subreq = subreq;
327 fsreq->pos = subreq->start + subreq->transferred;
328 fsreq->len = subreq->len - subreq->transferred;
329 fsreq->key = key_get(subreq->rreq->netfs_priv);
330 fsreq->vnode = vnode;
331 fsreq->iter = &subreq->io_iter;
332
333 trace_netfs_sreq(subreq, netfs_sreq_trace_submit);
334 afs_fetch_data(fsreq->vnode, fsreq);
335 afs_put_read(fsreq);
336}
337
338static void afs_issue_read(struct netfs_io_subrequest *subreq)
339{
340 INIT_WORK(&subreq->work, afs_read_worker);
341 queue_work(system_long_wq, &subreq->work);
342}
343
344static int afs_symlink_read_folio(struct file *file, struct folio *folio)
345{
346 struct afs_vnode *vnode = AFS_FS_I(folio->mapping->host);
347 struct afs_read *fsreq;
348 int ret;
349
350 fsreq = afs_alloc_read(GFP_NOFS);
351 if (!fsreq)
352 return -ENOMEM;
353
354 fsreq->pos = folio_pos(folio);
355 fsreq->len = folio_size(folio);
356 fsreq->vnode = vnode;
357 fsreq->iter = &fsreq->def_iter;
358 iov_iter_xarray(&fsreq->def_iter, ITER_DEST, &folio->mapping->i_pages,
359 fsreq->pos, fsreq->len);
360
361 ret = afs_fetch_data(fsreq->vnode, fsreq);
362 if (ret == 0)
363 folio_mark_uptodate(folio);
364 folio_unlock(folio);
365 return ret;
366}
367
368static int afs_init_request(struct netfs_io_request *rreq, struct file *file)
369{
370 if (file)
371 rreq->netfs_priv = key_get(afs_file_key(file));
372 rreq->rsize = 256 * 1024;
373 rreq->wsize = 256 * 1024 * 1024;
374 return 0;
375}
376
377static int afs_check_write_begin(struct file *file, loff_t pos, unsigned len,
378 struct folio **foliop, void **_fsdata)
379{
380 struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
381
382 return test_bit(AFS_VNODE_DELETED, &vnode->flags) ? -ESTALE : 0;
383}
384
385static void afs_free_request(struct netfs_io_request *rreq)
386{
387 key_put(rreq->netfs_priv);
388 afs_put_wb_key(rreq->netfs_priv2);
389}
390
391static void afs_update_i_size(struct inode *inode, loff_t new_i_size)
392{
393 struct afs_vnode *vnode = AFS_FS_I(inode);
394 loff_t i_size;
395
396 write_seqlock(&vnode->cb_lock);
397 i_size = i_size_read(&vnode->netfs.inode);
398 if (new_i_size > i_size) {
399 i_size_write(&vnode->netfs.inode, new_i_size);
400 inode_set_bytes(&vnode->netfs.inode, new_i_size);
401 }
402 write_sequnlock(&vnode->cb_lock);
403 fscache_update_cookie(afs_vnode_cache(vnode), NULL, &new_i_size);
404}
405
406static void afs_netfs_invalidate_cache(struct netfs_io_request *wreq)
407{
408 struct afs_vnode *vnode = AFS_FS_I(wreq->inode);
409
410 afs_invalidate_cache(vnode, 0);
411}
412
413const struct netfs_request_ops afs_req_ops = {
414 .init_request = afs_init_request,
415 .free_request = afs_free_request,
416 .check_write_begin = afs_check_write_begin,
417 .issue_read = afs_issue_read,
418 .update_i_size = afs_update_i_size,
419 .invalidate_cache = afs_netfs_invalidate_cache,
420 .begin_writeback = afs_begin_writeback,
421 .prepare_write = afs_prepare_write,
422 .issue_write = afs_issue_write,
423 .retry_request = afs_retry_request,
424};
425
426static void afs_add_open_mmap(struct afs_vnode *vnode)
427{
428 if (atomic_inc_return(&vnode->cb_nr_mmap) == 1) {
429 down_write(&vnode->volume->open_mmaps_lock);
430
431 if (list_empty(&vnode->cb_mmap_link))
432 list_add_tail(&vnode->cb_mmap_link, &vnode->volume->open_mmaps);
433
434 up_write(&vnode->volume->open_mmaps_lock);
435 }
436}
437
438static void afs_drop_open_mmap(struct afs_vnode *vnode)
439{
440 if (atomic_add_unless(&vnode->cb_nr_mmap, -1, 1))
441 return;
442
443 down_write(&vnode->volume->open_mmaps_lock);
444
445 read_seqlock_excl(&vnode->cb_lock);
446 // the only place where ->cb_nr_mmap may hit 0
447 // see __afs_break_callback() for the other side...
448 if (atomic_dec_and_test(&vnode->cb_nr_mmap))
449 list_del_init(&vnode->cb_mmap_link);
450 read_sequnlock_excl(&vnode->cb_lock);
451
452 up_write(&vnode->volume->open_mmaps_lock);
453 flush_work(&vnode->cb_work);
454}
455
456/*
457 * Handle setting up a memory mapping on an AFS file.
458 */
459static int afs_file_mmap(struct file *file, struct vm_area_struct *vma)
460{
461 struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
462 int ret;
463
464 afs_add_open_mmap(vnode);
465
466 ret = generic_file_mmap(file, vma);
467 if (ret == 0)
468 vma->vm_ops = &afs_vm_ops;
469 else
470 afs_drop_open_mmap(vnode);
471 return ret;
472}
473
474static void afs_vm_open(struct vm_area_struct *vma)
475{
476 afs_add_open_mmap(AFS_FS_I(file_inode(vma->vm_file)));
477}
478
479static void afs_vm_close(struct vm_area_struct *vma)
480{
481 afs_drop_open_mmap(AFS_FS_I(file_inode(vma->vm_file)));
482}
483
484static vm_fault_t afs_vm_map_pages(struct vm_fault *vmf, pgoff_t start_pgoff, pgoff_t end_pgoff)
485{
486 struct afs_vnode *vnode = AFS_FS_I(file_inode(vmf->vma->vm_file));
487
488 if (afs_check_validity(vnode))
489 return filemap_map_pages(vmf, start_pgoff, end_pgoff);
490 return 0;
491}
492
493static ssize_t afs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
494{
495 struct inode *inode = file_inode(iocb->ki_filp);
496 struct afs_vnode *vnode = AFS_FS_I(inode);
497 struct afs_file *af = iocb->ki_filp->private_data;
498 ssize_t ret;
499
500 if (iocb->ki_flags & IOCB_DIRECT)
501 return netfs_unbuffered_read_iter(iocb, iter);
502
503 ret = netfs_start_io_read(inode);
504 if (ret < 0)
505 return ret;
506 ret = afs_validate(vnode, af->key);
507 if (ret == 0)
508 ret = filemap_read(iocb, iter, 0);
509 netfs_end_io_read(inode);
510 return ret;
511}
512
513static ssize_t afs_file_splice_read(struct file *in, loff_t *ppos,
514 struct pipe_inode_info *pipe,
515 size_t len, unsigned int flags)
516{
517 struct inode *inode = file_inode(in);
518 struct afs_vnode *vnode = AFS_FS_I(inode);
519 struct afs_file *af = in->private_data;
520 ssize_t ret;
521
522 ret = netfs_start_io_read(inode);
523 if (ret < 0)
524 return ret;
525 ret = afs_validate(vnode, af->key);
526 if (ret == 0)
527 ret = filemap_splice_read(in, ppos, pipe, len, flags);
528 netfs_end_io_read(inode);
529 return ret;
530}
1// SPDX-License-Identifier: GPL-2.0-or-later
2/* AFS filesystem file handling
3 *
4 * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/fs.h>
12#include <linux/pagemap.h>
13#include <linux/writeback.h>
14#include <linux/gfp.h>
15#include <linux/task_io_accounting_ops.h>
16#include <linux/mm.h>
17#include <linux/netfs.h>
18#include "internal.h"
19
20static int afs_file_mmap(struct file *file, struct vm_area_struct *vma);
21static int afs_readpage(struct file *file, struct page *page);
22static void afs_invalidatepage(struct page *page, unsigned int offset,
23 unsigned int length);
24static int afs_releasepage(struct page *page, gfp_t gfp_flags);
25
26static void afs_readahead(struct readahead_control *ractl);
27static ssize_t afs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter);
28
29const struct file_operations afs_file_operations = {
30 .open = afs_open,
31 .release = afs_release,
32 .llseek = generic_file_llseek,
33 .read_iter = afs_file_read_iter,
34 .write_iter = afs_file_write,
35 .mmap = afs_file_mmap,
36 .splice_read = generic_file_splice_read,
37 .splice_write = iter_file_splice_write,
38 .fsync = afs_fsync,
39 .lock = afs_lock,
40 .flock = afs_flock,
41};
42
43const struct inode_operations afs_file_inode_operations = {
44 .getattr = afs_getattr,
45 .setattr = afs_setattr,
46 .permission = afs_permission,
47};
48
49const struct address_space_operations afs_fs_aops = {
50 .readpage = afs_readpage,
51 .readahead = afs_readahead,
52 .set_page_dirty = afs_set_page_dirty,
53 .launder_page = afs_launder_page,
54 .releasepage = afs_releasepage,
55 .invalidatepage = afs_invalidatepage,
56 .write_begin = afs_write_begin,
57 .write_end = afs_write_end,
58 .writepage = afs_writepage,
59 .writepages = afs_writepages,
60};
61
62static const struct vm_operations_struct afs_vm_ops = {
63 .fault = filemap_fault,
64 .map_pages = filemap_map_pages,
65 .page_mkwrite = afs_page_mkwrite,
66};
67
68/*
69 * Discard a pin on a writeback key.
70 */
71void afs_put_wb_key(struct afs_wb_key *wbk)
72{
73 if (wbk && refcount_dec_and_test(&wbk->usage)) {
74 key_put(wbk->key);
75 kfree(wbk);
76 }
77}
78
79/*
80 * Cache key for writeback.
81 */
82int afs_cache_wb_key(struct afs_vnode *vnode, struct afs_file *af)
83{
84 struct afs_wb_key *wbk, *p;
85
86 wbk = kzalloc(sizeof(struct afs_wb_key), GFP_KERNEL);
87 if (!wbk)
88 return -ENOMEM;
89 refcount_set(&wbk->usage, 2);
90 wbk->key = af->key;
91
92 spin_lock(&vnode->wb_lock);
93 list_for_each_entry(p, &vnode->wb_keys, vnode_link) {
94 if (p->key == wbk->key)
95 goto found;
96 }
97
98 key_get(wbk->key);
99 list_add_tail(&wbk->vnode_link, &vnode->wb_keys);
100 spin_unlock(&vnode->wb_lock);
101 af->wb = wbk;
102 return 0;
103
104found:
105 refcount_inc(&p->usage);
106 spin_unlock(&vnode->wb_lock);
107 af->wb = p;
108 kfree(wbk);
109 return 0;
110}
111
112/*
113 * open an AFS file or directory and attach a key to it
114 */
115int afs_open(struct inode *inode, struct file *file)
116{
117 struct afs_vnode *vnode = AFS_FS_I(inode);
118 struct afs_file *af;
119 struct key *key;
120 int ret;
121
122 _enter("{%llx:%llu},", vnode->fid.vid, vnode->fid.vnode);
123
124 key = afs_request_key(vnode->volume->cell);
125 if (IS_ERR(key)) {
126 ret = PTR_ERR(key);
127 goto error;
128 }
129
130 af = kzalloc(sizeof(*af), GFP_KERNEL);
131 if (!af) {
132 ret = -ENOMEM;
133 goto error_key;
134 }
135 af->key = key;
136
137 ret = afs_validate(vnode, key);
138 if (ret < 0)
139 goto error_af;
140
141 if (file->f_mode & FMODE_WRITE) {
142 ret = afs_cache_wb_key(vnode, af);
143 if (ret < 0)
144 goto error_af;
145 }
146
147 if (file->f_flags & O_TRUNC)
148 set_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags);
149
150 file->private_data = af;
151 _leave(" = 0");
152 return 0;
153
154error_af:
155 kfree(af);
156error_key:
157 key_put(key);
158error:
159 _leave(" = %d", ret);
160 return ret;
161}
162
163/*
164 * release an AFS file or directory and discard its key
165 */
166int afs_release(struct inode *inode, struct file *file)
167{
168 struct afs_vnode *vnode = AFS_FS_I(inode);
169 struct afs_file *af = file->private_data;
170 int ret = 0;
171
172 _enter("{%llx:%llu},", vnode->fid.vid, vnode->fid.vnode);
173
174 if ((file->f_mode & FMODE_WRITE))
175 ret = vfs_fsync(file, 0);
176
177 file->private_data = NULL;
178 if (af->wb)
179 afs_put_wb_key(af->wb);
180 key_put(af->key);
181 kfree(af);
182 afs_prune_wb_keys(vnode);
183 _leave(" = %d", ret);
184 return ret;
185}
186
187/*
188 * Allocate a new read record.
189 */
190struct afs_read *afs_alloc_read(gfp_t gfp)
191{
192 struct afs_read *req;
193
194 req = kzalloc(sizeof(struct afs_read), gfp);
195 if (req)
196 refcount_set(&req->usage, 1);
197
198 return req;
199}
200
201/*
202 * Dispose of a ref to a read record.
203 */
204void afs_put_read(struct afs_read *req)
205{
206 if (refcount_dec_and_test(&req->usage)) {
207 if (req->cleanup)
208 req->cleanup(req);
209 key_put(req->key);
210 kfree(req);
211 }
212}
213
214static void afs_fetch_data_notify(struct afs_operation *op)
215{
216 struct afs_read *req = op->fetch.req;
217 struct netfs_read_subrequest *subreq = req->subreq;
218 int error = op->error;
219
220 if (error == -ECONNABORTED)
221 error = afs_abort_to_error(op->ac.abort_code);
222 req->error = error;
223
224 if (subreq) {
225 __set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags);
226 netfs_subreq_terminated(subreq, error ?: req->actual_len, false);
227 req->subreq = NULL;
228 } else if (req->done) {
229 req->done(req);
230 }
231}
232
233static void afs_fetch_data_success(struct afs_operation *op)
234{
235 struct afs_vnode *vnode = op->file[0].vnode;
236
237 _enter("op=%08x", op->debug_id);
238 afs_vnode_commit_status(op, &op->file[0]);
239 afs_stat_v(vnode, n_fetches);
240 atomic_long_add(op->fetch.req->actual_len, &op->net->n_fetch_bytes);
241 afs_fetch_data_notify(op);
242}
243
244static void afs_fetch_data_put(struct afs_operation *op)
245{
246 op->fetch.req->error = op->error;
247 afs_put_read(op->fetch.req);
248}
249
250static const struct afs_operation_ops afs_fetch_data_operation = {
251 .issue_afs_rpc = afs_fs_fetch_data,
252 .issue_yfs_rpc = yfs_fs_fetch_data,
253 .success = afs_fetch_data_success,
254 .aborted = afs_check_for_remote_deletion,
255 .failed = afs_fetch_data_notify,
256 .put = afs_fetch_data_put,
257};
258
259/*
260 * Fetch file data from the volume.
261 */
262int afs_fetch_data(struct afs_vnode *vnode, struct afs_read *req)
263{
264 struct afs_operation *op;
265
266 _enter("%s{%llx:%llu.%u},%x,,,",
267 vnode->volume->name,
268 vnode->fid.vid,
269 vnode->fid.vnode,
270 vnode->fid.unique,
271 key_serial(req->key));
272
273 op = afs_alloc_operation(req->key, vnode->volume);
274 if (IS_ERR(op)) {
275 if (req->subreq)
276 netfs_subreq_terminated(req->subreq, PTR_ERR(op), false);
277 return PTR_ERR(op);
278 }
279
280 afs_op_set_vnode(op, 0, vnode);
281
282 op->fetch.req = afs_get_read(req);
283 op->ops = &afs_fetch_data_operation;
284 return afs_do_sync_operation(op);
285}
286
287static void afs_req_issue_op(struct netfs_read_subrequest *subreq)
288{
289 struct afs_vnode *vnode = AFS_FS_I(subreq->rreq->inode);
290 struct afs_read *fsreq;
291
292 fsreq = afs_alloc_read(GFP_NOFS);
293 if (!fsreq)
294 return netfs_subreq_terminated(subreq, -ENOMEM, false);
295
296 fsreq->subreq = subreq;
297 fsreq->pos = subreq->start + subreq->transferred;
298 fsreq->len = subreq->len - subreq->transferred;
299 fsreq->key = subreq->rreq->netfs_priv;
300 fsreq->vnode = vnode;
301 fsreq->iter = &fsreq->def_iter;
302
303 iov_iter_xarray(&fsreq->def_iter, READ,
304 &fsreq->vnode->vfs_inode.i_mapping->i_pages,
305 fsreq->pos, fsreq->len);
306
307 afs_fetch_data(fsreq->vnode, fsreq);
308}
309
310static int afs_symlink_readpage(struct page *page)
311{
312 struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
313 struct afs_read *fsreq;
314 int ret;
315
316 fsreq = afs_alloc_read(GFP_NOFS);
317 if (!fsreq)
318 return -ENOMEM;
319
320 fsreq->pos = page->index * PAGE_SIZE;
321 fsreq->len = PAGE_SIZE;
322 fsreq->vnode = vnode;
323 fsreq->iter = &fsreq->def_iter;
324 iov_iter_xarray(&fsreq->def_iter, READ, &page->mapping->i_pages,
325 fsreq->pos, fsreq->len);
326
327 ret = afs_fetch_data(fsreq->vnode, fsreq);
328 page_endio(page, false, ret);
329 return ret;
330}
331
332static void afs_init_rreq(struct netfs_read_request *rreq, struct file *file)
333{
334 rreq->netfs_priv = key_get(afs_file_key(file));
335}
336
337static bool afs_is_cache_enabled(struct inode *inode)
338{
339 struct fscache_cookie *cookie = afs_vnode_cache(AFS_FS_I(inode));
340
341 return fscache_cookie_enabled(cookie) && !hlist_empty(&cookie->backing_objects);
342}
343
344static int afs_begin_cache_operation(struct netfs_read_request *rreq)
345{
346 struct afs_vnode *vnode = AFS_FS_I(rreq->inode);
347
348 return fscache_begin_read_operation(rreq, afs_vnode_cache(vnode));
349}
350
351static int afs_check_write_begin(struct file *file, loff_t pos, unsigned len,
352 struct page *page, void **_fsdata)
353{
354 struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
355
356 return test_bit(AFS_VNODE_DELETED, &vnode->flags) ? -ESTALE : 0;
357}
358
359static void afs_priv_cleanup(struct address_space *mapping, void *netfs_priv)
360{
361 key_put(netfs_priv);
362}
363
364const struct netfs_read_request_ops afs_req_ops = {
365 .init_rreq = afs_init_rreq,
366 .is_cache_enabled = afs_is_cache_enabled,
367 .begin_cache_operation = afs_begin_cache_operation,
368 .check_write_begin = afs_check_write_begin,
369 .issue_op = afs_req_issue_op,
370 .cleanup = afs_priv_cleanup,
371};
372
373static int afs_readpage(struct file *file, struct page *page)
374{
375 if (!file)
376 return afs_symlink_readpage(page);
377
378 return netfs_readpage(file, page, &afs_req_ops, NULL);
379}
380
381static void afs_readahead(struct readahead_control *ractl)
382{
383 netfs_readahead(ractl, &afs_req_ops, NULL);
384}
385
386/*
387 * Adjust the dirty region of the page on truncation or full invalidation,
388 * getting rid of the markers altogether if the region is entirely invalidated.
389 */
390static void afs_invalidate_dirty(struct page *page, unsigned int offset,
391 unsigned int length)
392{
393 struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
394 unsigned long priv;
395 unsigned int f, t, end = offset + length;
396
397 priv = page_private(page);
398
399 /* we clean up only if the entire page is being invalidated */
400 if (offset == 0 && length == thp_size(page))
401 goto full_invalidate;
402
403 /* If the page was dirtied by page_mkwrite(), the PTE stays writable
404 * and we don't get another notification to tell us to expand it
405 * again.
406 */
407 if (afs_is_page_dirty_mmapped(priv))
408 return;
409
410 /* We may need to shorten the dirty region */
411 f = afs_page_dirty_from(page, priv);
412 t = afs_page_dirty_to(page, priv);
413
414 if (t <= offset || f >= end)
415 return; /* Doesn't overlap */
416
417 if (f < offset && t > end)
418 return; /* Splits the dirty region - just absorb it */
419
420 if (f >= offset && t <= end)
421 goto undirty;
422
423 if (f < offset)
424 t = offset;
425 else
426 f = end;
427 if (f == t)
428 goto undirty;
429
430 priv = afs_page_dirty(page, f, t);
431 set_page_private(page, priv);
432 trace_afs_page_dirty(vnode, tracepoint_string("trunc"), page);
433 return;
434
435undirty:
436 trace_afs_page_dirty(vnode, tracepoint_string("undirty"), page);
437 clear_page_dirty_for_io(page);
438full_invalidate:
439 trace_afs_page_dirty(vnode, tracepoint_string("inval"), page);
440 detach_page_private(page);
441}
442
443/*
444 * invalidate part or all of a page
445 * - release a page and clean up its private data if offset is 0 (indicating
446 * the entire page)
447 */
448static void afs_invalidatepage(struct page *page, unsigned int offset,
449 unsigned int length)
450{
451 _enter("{%lu},%u,%u", page->index, offset, length);
452
453 BUG_ON(!PageLocked(page));
454
455 if (PagePrivate(page))
456 afs_invalidate_dirty(page, offset, length);
457
458 wait_on_page_fscache(page);
459 _leave("");
460}
461
462/*
463 * release a page and clean up its private state if it's not busy
464 * - return true if the page can now be released, false if not
465 */
466static int afs_releasepage(struct page *page, gfp_t gfp_flags)
467{
468 struct afs_vnode *vnode = AFS_FS_I(page->mapping->host);
469
470 _enter("{{%llx:%llu}[%lu],%lx},%x",
471 vnode->fid.vid, vnode->fid.vnode, page->index, page->flags,
472 gfp_flags);
473
474 /* deny if page is being written to the cache and the caller hasn't
475 * elected to wait */
476#ifdef CONFIG_AFS_FSCACHE
477 if (PageFsCache(page)) {
478 if (!(gfp_flags & __GFP_DIRECT_RECLAIM) || !(gfp_flags & __GFP_FS))
479 return false;
480 wait_on_page_fscache(page);
481 }
482#endif
483
484 if (PagePrivate(page)) {
485 trace_afs_page_dirty(vnode, tracepoint_string("rel"), page);
486 detach_page_private(page);
487 }
488
489 /* indicate that the page can be released */
490 _leave(" = T");
491 return 1;
492}
493
494/*
495 * Handle setting up a memory mapping on an AFS file.
496 */
497static int afs_file_mmap(struct file *file, struct vm_area_struct *vma)
498{
499 int ret;
500
501 ret = generic_file_mmap(file, vma);
502 if (ret == 0)
503 vma->vm_ops = &afs_vm_ops;
504 return ret;
505}
506
507static ssize_t afs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter)
508{
509 struct afs_vnode *vnode = AFS_FS_I(file_inode(iocb->ki_filp));
510 struct afs_file *af = iocb->ki_filp->private_data;
511 int ret;
512
513 ret = afs_validate(vnode, af->key);
514 if (ret < 0)
515 return ret;
516
517 return generic_file_read_iter(iocb, iter);
518}