1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Read with PG_private_2 [DEPRECATED].
4 * Copyright (C) 2024 Red Hat, Inc. All Rights Reserved.
8 #include <linux/export.h>
11 #include <linux/pagemap.h>
12 #include <linux/slab.h>
13 #include <linux/task_io_accounting_ops.h>
17 * [DEPRECATED] Mark page as requiring copy-to-cache using PG_private_2. The
18 * third mark in the folio queue is used to indicate that this folio needs
21 void netfs_pgpriv2_mark_copy_to_cache(struct netfs_io_subrequest *subreq,
22 struct netfs_io_request *rreq,
23 struct folio_queue *folioq,
26 struct folio *folio = folioq_folio(folioq, slot);
28 trace_netfs_folio(folio, netfs_folio_trace_copy_to_cache);
29 folio_start_private_2(folio);
30 folioq_mark3(folioq, slot);
34 * [DEPRECATED] Cancel PG_private_2 on all marked folios in the event of an
35 * unrecoverable error.
37 static void netfs_pgpriv2_cancel(struct folio_queue *folioq)
43 if (!folioq->marks3) {
44 folioq = folioq->next;
48 slot = __ffs(folioq->marks3);
49 folio = folioq_folio(folioq, slot);
51 trace_netfs_folio(folio, netfs_folio_trace_cancel_copy);
52 folio_end_private_2(folio);
53 folioq_unmark3(folioq, slot);
58 * [DEPRECATED] Copy a folio to the cache with PG_private_2 set.
60 static int netfs_pgpriv2_copy_folio(struct netfs_io_request *wreq, struct folio *folio)
62 struct netfs_io_stream *cache = &wreq->io_streams[1];
63 size_t fsize = folio_size(folio), flen = fsize;
64 loff_t fpos = folio_pos(folio), i_size;
69 /* netfs_perform_write() may shift i_size around the page or from out
70 * of the page to beyond it, but cannot move i_size into or through the
71 * page since we have it locked.
73 i_size = i_size_read(wreq->inode);
76 /* mmap beyond eof. */
78 folio_end_private_2(folio);
82 if (fpos + fsize > wreq->i_size)
83 wreq->i_size = i_size;
85 if (flen > i_size - fpos) {
88 } else if (flen == i_size - fpos) {
92 _debug("folio %zx %zx", flen, fsize);
94 trace_netfs_folio(folio, netfs_folio_trace_store_copy);
96 /* Attach the folio to the rolling buffer. */
97 if (netfs_buffer_append_folio(wreq, folio, false) < 0)
100 cache->submit_extendable_to = fsize;
101 cache->submit_off = 0;
102 cache->submit_len = flen;
104 /* Attach the folio to one or more subrequests. For a big folio, we
105 * could end up with thousands of subrequests if the wsize is small -
106 * but we might need to wait during the creation of subrequests for
107 * network resources (eg. SMB credits).
112 wreq->io_iter.iov_offset = cache->submit_off;
114 atomic64_set(&wreq->issued_to, fpos + cache->submit_off);
115 cache->submit_extendable_to = fsize - cache->submit_off;
116 part = netfs_advance_write(wreq, cache, fpos + cache->submit_off,
117 cache->submit_len, to_eof);
118 cache->submit_off += part;
119 if (part > cache->submit_len)
120 cache->submit_len = 0;
122 cache->submit_len -= part;
123 } while (cache->submit_len > 0);
125 wreq->io_iter.iov_offset = 0;
126 iov_iter_advance(&wreq->io_iter, fsize);
127 atomic64_set(&wreq->issued_to, fpos + fsize);
130 netfs_issue_write(wreq, cache);
137 * [DEPRECATED] Go through the buffer and write any folios that are marked with
138 * the third mark to the cache.
140 void netfs_pgpriv2_write_to_the_cache(struct netfs_io_request *rreq)
142 struct netfs_io_request *wreq;
143 struct folio_queue *folioq;
150 if (!fscache_resources_valid(&rreq->cache_resources))
153 /* Need the first folio to be able to set up the op. */
154 for (folioq = rreq->buffer; folioq; folioq = folioq->next) {
155 if (folioq->marks3) {
156 slot = __ffs(folioq->marks3);
162 folio = folioq_folio(folioq, slot);
164 wreq = netfs_create_write_req(rreq->mapping, NULL, folio_pos(folio),
165 NETFS_PGPRIV2_COPY_TO_CACHE);
167 kleave(" [create %ld]", PTR_ERR(wreq));
171 trace_netfs_write(wreq, netfs_write_trace_copy_to_cache);
172 netfs_stat(&netfs_n_wh_copy_to_cache);
173 if (!wreq->io_streams[1].avail) {
174 netfs_put_request(wreq, false, netfs_rreq_trace_put_return);
179 error = netfs_pgpriv2_copy_folio(wreq, folio);
183 folioq_unmark3(folioq, slot);
184 if (!folioq->marks3) {
185 folioq = folioq->next;
190 slot = __ffs(folioq->marks3);
191 folio = folioq_folio(folioq, slot);
194 netfs_issue_write(wreq, &wreq->io_streams[1]);
195 smp_wmb(); /* Write lists before ALL_QUEUED. */
196 set_bit(NETFS_RREQ_ALL_QUEUED, &wreq->flags);
198 netfs_put_request(wreq, false, netfs_rreq_trace_put_return);
199 _leave(" = %d", error);
201 netfs_pgpriv2_cancel(rreq->buffer);
205 * [DEPRECATED] Remove the PG_private_2 mark from any folios we've finished
208 bool netfs_pgpriv2_unlock_copied_folios(struct netfs_io_request *wreq)
210 struct folio_queue *folioq = wreq->buffer;
211 unsigned long long collected_to = wreq->collected_to;
212 unsigned int slot = wreq->buffer_head_slot;
213 bool made_progress = false;
215 if (slot >= folioq_nr_slots(folioq)) {
216 folioq = netfs_delete_buffer_head(wreq);
222 unsigned long long fpos, fend;
225 folio = folioq_folio(folioq, slot);
226 if (WARN_ONCE(!folio_test_private_2(folio),
227 "R=%08x: folio %lx is not marked private_2\n",
228 wreq->debug_id, folio->index))
229 trace_netfs_folio(folio, netfs_folio_trace_not_under_wback);
231 fpos = folio_pos(folio);
232 fsize = folio_size(folio);
235 fend = min_t(unsigned long long, fpos + flen, wreq->i_size);
237 trace_netfs_collect_folio(wreq, folio, fend, collected_to);
239 /* Unlock any folio we've transferred all of. */
240 if (collected_to < fend)
243 trace_netfs_folio(folio, netfs_folio_trace_end_copy);
244 folio_end_private_2(folio);
245 wreq->cleaned_to = fpos + fsize;
246 made_progress = true;
248 /* Clean up the head folioq. If we clear an entire folioq, then
249 * we can get rid of it provided it's not also the tail folioq
250 * being filled by the issuer.
252 folioq_clear(folioq, slot);
254 if (slot >= folioq_nr_slots(folioq)) {
255 if (READ_ONCE(wreq->buffer_tail) == folioq)
257 folioq = netfs_delete_buffer_head(wreq);
261 if (fpos + fsize >= collected_to)
265 wreq->buffer = folioq;
266 wreq->buffer_head_slot = slot;
267 return made_progress;