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Commit ff638b7df5a9264024a6448bdfde2b2bf5d1994a

Authored by Li Wang
Committed by Sage Weil
1 parent fc55d2c944
Exists in smarc-imx_3.14.28_1.0.0_ga and in 1 other branch imx_3.14.28_1.0.0_ga

ceph: allocate non-zero page to fscache in readpage() 

ceph_osdc_readpages() returns number of bytes read, currently,
the code only allocate full-zero page into fscache, this patch
fixes this.

Signed-off-by: Li Wang <liwang@ubuntukylin.com>
Reviewed-by: Milosz Tanski <milosz@adfin.com>
Reviewed-by: Sage Weil <sage@inktank.com>

Showing 1 changed file with 1 additions and 1 deletions Inline Diff

1 #include <linux/ceph/ceph_debug.h> 1 #include <linux/ceph/ceph_debug.h>
2 2
3 #include <linux/backing-dev.h> 3 #include <linux/backing-dev.h>
4 #include <linux/fs.h> 4 #include <linux/fs.h>
5 #include <linux/mm.h> 5 #include <linux/mm.h>
6 #include <linux/pagemap.h> 6 #include <linux/pagemap.h>
7 #include <linux/writeback.h> /* generic_writepages */ 7 #include <linux/writeback.h> /* generic_writepages */
8 #include <linux/slab.h> 8 #include <linux/slab.h>
9 #include <linux/pagevec.h> 9 #include <linux/pagevec.h>
10 #include <linux/task_io_accounting_ops.h> 10 #include <linux/task_io_accounting_ops.h>
11 11
12 #include "super.h" 12 #include "super.h"
13 #include "mds_client.h" 13 #include "mds_client.h"
14 #include "cache.h" 14 #include "cache.h"
15 #include <linux/ceph/osd_client.h> 15 #include <linux/ceph/osd_client.h>
16 16
17 /* 17 /*
18 * Ceph address space ops. 18 * Ceph address space ops.
19 * 19 *
20 * There are a few funny things going on here. 20 * There are a few funny things going on here.
21 * 21 *
22 * The page->private field is used to reference a struct 22 * The page->private field is used to reference a struct
23 * ceph_snap_context for _every_ dirty page. This indicates which 23 * ceph_snap_context for _every_ dirty page. This indicates which
24 * snapshot the page was logically dirtied in, and thus which snap 24 * snapshot the page was logically dirtied in, and thus which snap
25 * context needs to be associated with the osd write during writeback. 25 * context needs to be associated with the osd write during writeback.
26 * 26 *
27 * Similarly, struct ceph_inode_info maintains a set of counters to 27 * Similarly, struct ceph_inode_info maintains a set of counters to
28 * count dirty pages on the inode. In the absence of snapshots, 28 * count dirty pages on the inode. In the absence of snapshots,
29 * i_wrbuffer_ref == i_wrbuffer_ref_head == the dirty page count. 29 * i_wrbuffer_ref == i_wrbuffer_ref_head == the dirty page count.
30 * 30 *
31 * When a snapshot is taken (that is, when the client receives 31 * When a snapshot is taken (that is, when the client receives
32 * notification that a snapshot was taken), each inode with caps and 32 * notification that a snapshot was taken), each inode with caps and
33 * with dirty pages (dirty pages implies there is a cap) gets a new 33 * with dirty pages (dirty pages implies there is a cap) gets a new
34 * ceph_cap_snap in the i_cap_snaps list (which is sorted in ascending 34 * ceph_cap_snap in the i_cap_snaps list (which is sorted in ascending
35 * order, new snaps go to the tail). The i_wrbuffer_ref_head count is 35 * order, new snaps go to the tail). The i_wrbuffer_ref_head count is
36 * moved to capsnap->dirty. (Unless a sync write is currently in 36 * moved to capsnap->dirty. (Unless a sync write is currently in
37 * progress. In that case, the capsnap is said to be "pending", new 37 * progress. In that case, the capsnap is said to be "pending", new
38 * writes cannot start, and the capsnap isn't "finalized" until the 38 * writes cannot start, and the capsnap isn't "finalized" until the
39 * write completes (or fails) and a final size/mtime for the inode for 39 * write completes (or fails) and a final size/mtime for the inode for
40 * that snap can be settled upon.) i_wrbuffer_ref_head is reset to 0. 40 * that snap can be settled upon.) i_wrbuffer_ref_head is reset to 0.
41 * 41 *
42 * On writeback, we must submit writes to the osd IN SNAP ORDER. So, 42 * On writeback, we must submit writes to the osd IN SNAP ORDER. So,
43 * we look for the first capsnap in i_cap_snaps and write out pages in 43 * we look for the first capsnap in i_cap_snaps and write out pages in
44 * that snap context _only_. Then we move on to the next capsnap, 44 * that snap context _only_. Then we move on to the next capsnap,
45 * eventually reaching the "live" or "head" context (i.e., pages that 45 * eventually reaching the "live" or "head" context (i.e., pages that
46 * are not yet snapped) and are writing the most recently dirtied 46 * are not yet snapped) and are writing the most recently dirtied
47 * pages. 47 * pages.
48 * 48 *
49 * Invalidate and so forth must take care to ensure the dirty page 49 * Invalidate and so forth must take care to ensure the dirty page
50 * accounting is preserved. 50 * accounting is preserved.
51 */ 51 */
52 52
53 #define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10)) 53 #define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10))
54 #define CONGESTION_OFF_THRESH(congestion_kb) \ 54 #define CONGESTION_OFF_THRESH(congestion_kb) \
55 (CONGESTION_ON_THRESH(congestion_kb) - \ 55 (CONGESTION_ON_THRESH(congestion_kb) - \
56 (CONGESTION_ON_THRESH(congestion_kb) >> 2)) 56 (CONGESTION_ON_THRESH(congestion_kb) >> 2))
57 57
58 static inline struct ceph_snap_context *page_snap_context(struct page *page) 58 static inline struct ceph_snap_context *page_snap_context(struct page *page)
59 { 59 {
60 if (PagePrivate(page)) 60 if (PagePrivate(page))
61 return (void *)page->private; 61 return (void *)page->private;
62 return NULL; 62 return NULL;
63 } 63 }
64 64
65 /* 65 /*
66 * Dirty a page. Optimistically adjust accounting, on the assumption 66 * Dirty a page. Optimistically adjust accounting, on the assumption
67 * that we won't race with invalidate. If we do, readjust. 67 * that we won't race with invalidate. If we do, readjust.
68 */ 68 */
69 static int ceph_set_page_dirty(struct page *page) 69 static int ceph_set_page_dirty(struct page *page)
70 { 70 {
71 struct address_space *mapping = page->mapping; 71 struct address_space *mapping = page->mapping;
72 struct inode *inode; 72 struct inode *inode;
73 struct ceph_inode_info *ci; 73 struct ceph_inode_info *ci;
74 struct ceph_snap_context *snapc; 74 struct ceph_snap_context *snapc;
75 int ret; 75 int ret;
76 76
77 if (unlikely(!mapping)) 77 if (unlikely(!mapping))
78 return !TestSetPageDirty(page); 78 return !TestSetPageDirty(page);
79 79
80 if (PageDirty(page)) { 80 if (PageDirty(page)) {
81 dout("%p set_page_dirty %p idx %lu -- already dirty\n", 81 dout("%p set_page_dirty %p idx %lu -- already dirty\n",
82 mapping->host, page, page->index); 82 mapping->host, page, page->index);
83 BUG_ON(!PagePrivate(page)); 83 BUG_ON(!PagePrivate(page));
84 return 0; 84 return 0;
85 } 85 }
86 86
87 inode = mapping->host; 87 inode = mapping->host;
88 ci = ceph_inode(inode); 88 ci = ceph_inode(inode);
89 89
90 /* 90 /*
91 * Note that we're grabbing a snapc ref here without holding 91 * Note that we're grabbing a snapc ref here without holding
92 * any locks! 92 * any locks!
93 */ 93 */
94 snapc = ceph_get_snap_context(ci->i_snap_realm->cached_context); 94 snapc = ceph_get_snap_context(ci->i_snap_realm->cached_context);
95 95
96 /* dirty the head */ 96 /* dirty the head */
97 spin_lock(&ci->i_ceph_lock); 97 spin_lock(&ci->i_ceph_lock);
98 if (ci->i_head_snapc == NULL) 98 if (ci->i_head_snapc == NULL)
99 ci->i_head_snapc = ceph_get_snap_context(snapc); 99 ci->i_head_snapc = ceph_get_snap_context(snapc);
100 ++ci->i_wrbuffer_ref_head; 100 ++ci->i_wrbuffer_ref_head;
101 if (ci->i_wrbuffer_ref == 0) 101 if (ci->i_wrbuffer_ref == 0)
102 ihold(inode); 102 ihold(inode);
103 ++ci->i_wrbuffer_ref; 103 ++ci->i_wrbuffer_ref;
104 dout("%p set_page_dirty %p idx %lu head %d/%d -> %d/%d " 104 dout("%p set_page_dirty %p idx %lu head %d/%d -> %d/%d "
105 "snapc %p seq %lld (%d snaps)\n", 105 "snapc %p seq %lld (%d snaps)\n",
106 mapping->host, page, page->index, 106 mapping->host, page, page->index,
107 ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref_head-1, 107 ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref_head-1,
108 ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head, 108 ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head,
109 snapc, snapc->seq, snapc->num_snaps); 109 snapc, snapc->seq, snapc->num_snaps);
110 spin_unlock(&ci->i_ceph_lock); 110 spin_unlock(&ci->i_ceph_lock);
111 111
112 /* 112 /*
113 * Reference snap context in page->private. Also set 113 * Reference snap context in page->private. Also set
114 * PagePrivate so that we get invalidatepage callback. 114 * PagePrivate so that we get invalidatepage callback.
115 */ 115 */
116 BUG_ON(PagePrivate(page)); 116 BUG_ON(PagePrivate(page));
117 page->private = (unsigned long)snapc; 117 page->private = (unsigned long)snapc;
118 SetPagePrivate(page); 118 SetPagePrivate(page);
119 119
120 ret = __set_page_dirty_nobuffers(page); 120 ret = __set_page_dirty_nobuffers(page);
121 WARN_ON(!PageLocked(page)); 121 WARN_ON(!PageLocked(page));
122 WARN_ON(!page->mapping); 122 WARN_ON(!page->mapping);
123 123
124 return ret; 124 return ret;
125 } 125 }
126 126
127 /* 127 /*
128 * If we are truncating the full page (i.e. offset == 0), adjust the 128 * If we are truncating the full page (i.e. offset == 0), adjust the
129 * dirty page counters appropriately. Only called if there is private 129 * dirty page counters appropriately. Only called if there is private
130 * data on the page. 130 * data on the page.
131 */ 131 */
132 static void ceph_invalidatepage(struct page *page, unsigned int offset, 132 static void ceph_invalidatepage(struct page *page, unsigned int offset,
133 unsigned int length) 133 unsigned int length)
134 { 134 {
135 struct inode *inode; 135 struct inode *inode;
136 struct ceph_inode_info *ci; 136 struct ceph_inode_info *ci;
137 struct ceph_snap_context *snapc = page_snap_context(page); 137 struct ceph_snap_context *snapc = page_snap_context(page);
138 138
139 inode = page->mapping->host; 139 inode = page->mapping->host;
140 ci = ceph_inode(inode); 140 ci = ceph_inode(inode);
141 141
142 if (offset != 0 || length != PAGE_CACHE_SIZE) { 142 if (offset != 0 || length != PAGE_CACHE_SIZE) {
143 dout("%p invalidatepage %p idx %lu partial dirty page %u~%u\n", 143 dout("%p invalidatepage %p idx %lu partial dirty page %u~%u\n",
144 inode, page, page->index, offset, length); 144 inode, page, page->index, offset, length);
145 return; 145 return;
146 } 146 }
147 147
148 ceph_invalidate_fscache_page(inode, page); 148 ceph_invalidate_fscache_page(inode, page);
149 149
150 if (!PagePrivate(page)) 150 if (!PagePrivate(page))
151 return; 151 return;
152 152
153 /* 153 /*
154 * We can get non-dirty pages here due to races between 154 * We can get non-dirty pages here due to races between
155 * set_page_dirty and truncate_complete_page; just spit out a 155 * set_page_dirty and truncate_complete_page; just spit out a
156 * warning, in case we end up with accounting problems later. 156 * warning, in case we end up with accounting problems later.
157 */ 157 */
158 if (!PageDirty(page)) 158 if (!PageDirty(page))
159 pr_err("%p invalidatepage %p page not dirty\n", inode, page); 159 pr_err("%p invalidatepage %p page not dirty\n", inode, page);
160 160
161 ClearPageChecked(page); 161 ClearPageChecked(page);
162 162
163 dout("%p invalidatepage %p idx %lu full dirty page\n", 163 dout("%p invalidatepage %p idx %lu full dirty page\n",
164 inode, page, page->index); 164 inode, page, page->index);
165 165
166 ceph_put_wrbuffer_cap_refs(ci, 1, snapc); 166 ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
167 ceph_put_snap_context(snapc); 167 ceph_put_snap_context(snapc);
168 page->private = 0; 168 page->private = 0;
169 ClearPagePrivate(page); 169 ClearPagePrivate(page);
170 } 170 }
171 171
172 static int ceph_releasepage(struct page *page, gfp_t g) 172 static int ceph_releasepage(struct page *page, gfp_t g)
173 { 173 {
174 struct inode *inode = page->mapping ? page->mapping->host : NULL; 174 struct inode *inode = page->mapping ? page->mapping->host : NULL;
175 dout("%p releasepage %p idx %lu\n", inode, page, page->index); 175 dout("%p releasepage %p idx %lu\n", inode, page, page->index);
176 WARN_ON(PageDirty(page)); 176 WARN_ON(PageDirty(page));
177 177
178 /* Can we release the page from the cache? */ 178 /* Can we release the page from the cache? */
179 if (!ceph_release_fscache_page(page, g)) 179 if (!ceph_release_fscache_page(page, g))
180 return 0; 180 return 0;
181 181
182 return !PagePrivate(page); 182 return !PagePrivate(page);
183 } 183 }
184 184
185 /* 185 /*
186 * read a single page, without unlocking it. 186 * read a single page, without unlocking it.
187 */ 187 */
188 static int readpage_nounlock(struct file *filp, struct page *page) 188 static int readpage_nounlock(struct file *filp, struct page *page)
189 { 189 {
190 struct inode *inode = file_inode(filp); 190 struct inode *inode = file_inode(filp);
191 struct ceph_inode_info *ci = ceph_inode(inode); 191 struct ceph_inode_info *ci = ceph_inode(inode);
192 struct ceph_osd_client *osdc = 192 struct ceph_osd_client *osdc =
193 &ceph_inode_to_client(inode)->client->osdc; 193 &ceph_inode_to_client(inode)->client->osdc;
194 int err = 0; 194 int err = 0;
195 u64 len = PAGE_CACHE_SIZE; 195 u64 len = PAGE_CACHE_SIZE;
196 196
197 err = ceph_readpage_from_fscache(inode, page); 197 err = ceph_readpage_from_fscache(inode, page);
198 198
199 if (err == 0) 199 if (err == 0)
200 goto out; 200 goto out;
201 201
202 dout("readpage inode %p file %p page %p index %lu\n", 202 dout("readpage inode %p file %p page %p index %lu\n",
203 inode, filp, page, page->index); 203 inode, filp, page, page->index);
204 err = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout, 204 err = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout,
205 (u64) page_offset(page), &len, 205 (u64) page_offset(page), &len,
206 ci->i_truncate_seq, ci->i_truncate_size, 206 ci->i_truncate_seq, ci->i_truncate_size,
207 &page, 1, 0); 207 &page, 1, 0);
208 if (err == -ENOENT) 208 if (err == -ENOENT)
209 err = 0; 209 err = 0;
210 if (err < 0) { 210 if (err < 0) {
211 SetPageError(page); 211 SetPageError(page);
212 goto out; 212 goto out;
213 } else if (err < PAGE_CACHE_SIZE) { 213 } else if (err < PAGE_CACHE_SIZE) {
214 /* zero fill remainder of page */ 214 /* zero fill remainder of page */
215 zero_user_segment(page, err, PAGE_CACHE_SIZE); 215 zero_user_segment(page, err, PAGE_CACHE_SIZE);
216 } 216 }
217 SetPageUptodate(page); 217 SetPageUptodate(page);
218 218
219 if (err == 0) 219 if (err >= 0)
220 ceph_readpage_to_fscache(inode, page); 220 ceph_readpage_to_fscache(inode, page);
221 221
222 out: 222 out:
223 return err < 0 ? err : 0; 223 return err < 0 ? err : 0;
224 } 224 }
225 225
226 static int ceph_readpage(struct file *filp, struct page *page) 226 static int ceph_readpage(struct file *filp, struct page *page)
227 { 227 {
228 int r = readpage_nounlock(filp, page); 228 int r = readpage_nounlock(filp, page);
229 unlock_page(page); 229 unlock_page(page);
230 return r; 230 return r;
231 } 231 }
232 232
233 /* 233 /*
234 * Finish an async read(ahead) op. 234 * Finish an async read(ahead) op.
235 */ 235 */
236 static void finish_read(struct ceph_osd_request *req, struct ceph_msg *msg) 236 static void finish_read(struct ceph_osd_request *req, struct ceph_msg *msg)
237 { 237 {
238 struct inode *inode = req->r_inode; 238 struct inode *inode = req->r_inode;
239 struct ceph_osd_data *osd_data; 239 struct ceph_osd_data *osd_data;
240 int rc = req->r_result; 240 int rc = req->r_result;
241 int bytes = le32_to_cpu(msg->hdr.data_len); 241 int bytes = le32_to_cpu(msg->hdr.data_len);
242 int num_pages; 242 int num_pages;
243 int i; 243 int i;
244 244
245 dout("finish_read %p req %p rc %d bytes %d\n", inode, req, rc, bytes); 245 dout("finish_read %p req %p rc %d bytes %d\n", inode, req, rc, bytes);
246 246
247 /* unlock all pages, zeroing any data we didn't read */ 247 /* unlock all pages, zeroing any data we didn't read */
248 osd_data = osd_req_op_extent_osd_data(req, 0); 248 osd_data = osd_req_op_extent_osd_data(req, 0);
249 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES); 249 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
250 num_pages = calc_pages_for((u64)osd_data->alignment, 250 num_pages = calc_pages_for((u64)osd_data->alignment,
251 (u64)osd_data->length); 251 (u64)osd_data->length);
252 for (i = 0; i < num_pages; i++) { 252 for (i = 0; i < num_pages; i++) {
253 struct page *page = osd_data->pages[i]; 253 struct page *page = osd_data->pages[i];
254 254
255 if (bytes < (int)PAGE_CACHE_SIZE) { 255 if (bytes < (int)PAGE_CACHE_SIZE) {
256 /* zero (remainder of) page */ 256 /* zero (remainder of) page */
257 int s = bytes < 0 ? 0 : bytes; 257 int s = bytes < 0 ? 0 : bytes;
258 zero_user_segment(page, s, PAGE_CACHE_SIZE); 258 zero_user_segment(page, s, PAGE_CACHE_SIZE);
259 } 259 }
260 dout("finish_read %p uptodate %p idx %lu\n", inode, page, 260 dout("finish_read %p uptodate %p idx %lu\n", inode, page,
261 page->index); 261 page->index);
262 flush_dcache_page(page); 262 flush_dcache_page(page);
263 SetPageUptodate(page); 263 SetPageUptodate(page);
264 ceph_readpage_to_fscache(inode, page); 264 ceph_readpage_to_fscache(inode, page);
265 unlock_page(page); 265 unlock_page(page);
266 page_cache_release(page); 266 page_cache_release(page);
267 bytes -= PAGE_CACHE_SIZE; 267 bytes -= PAGE_CACHE_SIZE;
268 } 268 }
269 kfree(osd_data->pages); 269 kfree(osd_data->pages);
270 } 270 }
271 271
272 static void ceph_unlock_page_vector(struct page **pages, int num_pages) 272 static void ceph_unlock_page_vector(struct page **pages, int num_pages)
273 { 273 {
274 int i; 274 int i;
275 275
276 for (i = 0; i < num_pages; i++) 276 for (i = 0; i < num_pages; i++)
277 unlock_page(pages[i]); 277 unlock_page(pages[i]);
278 } 278 }
279 279
280 /* 280 /*
281 * start an async read(ahead) operation. return nr_pages we submitted 281 * start an async read(ahead) operation. return nr_pages we submitted
282 * a read for on success, or negative error code. 282 * a read for on success, or negative error code.
283 */ 283 */
284 static int start_read(struct inode *inode, struct list_head *page_list, int max) 284 static int start_read(struct inode *inode, struct list_head *page_list, int max)
285 { 285 {
286 struct ceph_osd_client *osdc = 286 struct ceph_osd_client *osdc =
287 &ceph_inode_to_client(inode)->client->osdc; 287 &ceph_inode_to_client(inode)->client->osdc;
288 struct ceph_inode_info *ci = ceph_inode(inode); 288 struct ceph_inode_info *ci = ceph_inode(inode);
289 struct page *page = list_entry(page_list->prev, struct page, lru); 289 struct page *page = list_entry(page_list->prev, struct page, lru);
290 struct ceph_vino vino; 290 struct ceph_vino vino;
291 struct ceph_osd_request *req; 291 struct ceph_osd_request *req;
292 u64 off; 292 u64 off;
293 u64 len; 293 u64 len;
294 int i; 294 int i;
295 struct page **pages; 295 struct page **pages;
296 pgoff_t next_index; 296 pgoff_t next_index;
297 int nr_pages = 0; 297 int nr_pages = 0;
298 int ret; 298 int ret;
299 299
300 off = (u64) page_offset(page); 300 off = (u64) page_offset(page);
301 301
302 /* count pages */ 302 /* count pages */
303 next_index = page->index; 303 next_index = page->index;
304 list_for_each_entry_reverse(page, page_list, lru) { 304 list_for_each_entry_reverse(page, page_list, lru) {
305 if (page->index != next_index) 305 if (page->index != next_index)
306 break; 306 break;
307 nr_pages++; 307 nr_pages++;
308 next_index++; 308 next_index++;
309 if (max && nr_pages == max) 309 if (max && nr_pages == max)
310 break; 310 break;
311 } 311 }
312 len = nr_pages << PAGE_CACHE_SHIFT; 312 len = nr_pages << PAGE_CACHE_SHIFT;
313 dout("start_read %p nr_pages %d is %lld~%lld\n", inode, nr_pages, 313 dout("start_read %p nr_pages %d is %lld~%lld\n", inode, nr_pages,
314 off, len); 314 off, len);
315 vino = ceph_vino(inode); 315 vino = ceph_vino(inode);
316 req = ceph_osdc_new_request(osdc, &ci->i_layout, vino, off, &len, 316 req = ceph_osdc_new_request(osdc, &ci->i_layout, vino, off, &len,
317 1, CEPH_OSD_OP_READ, 317 1, CEPH_OSD_OP_READ,
318 CEPH_OSD_FLAG_READ, NULL, 318 CEPH_OSD_FLAG_READ, NULL,
319 ci->i_truncate_seq, ci->i_truncate_size, 319 ci->i_truncate_seq, ci->i_truncate_size,
320 false); 320 false);
321 if (IS_ERR(req)) 321 if (IS_ERR(req))
322 return PTR_ERR(req); 322 return PTR_ERR(req);
323 323
324 /* build page vector */ 324 /* build page vector */
325 nr_pages = calc_pages_for(0, len); 325 nr_pages = calc_pages_for(0, len);
326 pages = kmalloc(sizeof(*pages) * nr_pages, GFP_NOFS); 326 pages = kmalloc(sizeof(*pages) * nr_pages, GFP_NOFS);
327 ret = -ENOMEM; 327 ret = -ENOMEM;
328 if (!pages) 328 if (!pages)
329 goto out; 329 goto out;
330 for (i = 0; i < nr_pages; ++i) { 330 for (i = 0; i < nr_pages; ++i) {
331 page = list_entry(page_list->prev, struct page, lru); 331 page = list_entry(page_list->prev, struct page, lru);
332 BUG_ON(PageLocked(page)); 332 BUG_ON(PageLocked(page));
333 list_del(&page->lru); 333 list_del(&page->lru);
334 334
335 dout("start_read %p adding %p idx %lu\n", inode, page, 335 dout("start_read %p adding %p idx %lu\n", inode, page,
336 page->index); 336 page->index);
337 if (add_to_page_cache_lru(page, &inode->i_data, page->index, 337 if (add_to_page_cache_lru(page, &inode->i_data, page->index,
338 GFP_NOFS)) { 338 GFP_NOFS)) {
339 ceph_fscache_uncache_page(inode, page); 339 ceph_fscache_uncache_page(inode, page);
340 page_cache_release(page); 340 page_cache_release(page);
341 dout("start_read %p add_to_page_cache failed %p\n", 341 dout("start_read %p add_to_page_cache failed %p\n",
342 inode, page); 342 inode, page);
343 nr_pages = i; 343 nr_pages = i;
344 goto out_pages; 344 goto out_pages;
345 } 345 }
346 pages[i] = page; 346 pages[i] = page;
347 } 347 }
348 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false); 348 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false);
349 req->r_callback = finish_read; 349 req->r_callback = finish_read;
350 req->r_inode = inode; 350 req->r_inode = inode;
351 351
352 ceph_osdc_build_request(req, off, NULL, vino.snap, NULL); 352 ceph_osdc_build_request(req, off, NULL, vino.snap, NULL);
353 353
354 dout("start_read %p starting %p %lld~%lld\n", inode, req, off, len); 354 dout("start_read %p starting %p %lld~%lld\n", inode, req, off, len);
355 ret = ceph_osdc_start_request(osdc, req, false); 355 ret = ceph_osdc_start_request(osdc, req, false);
356 if (ret < 0) 356 if (ret < 0)
357 goto out_pages; 357 goto out_pages;
358 ceph_osdc_put_request(req); 358 ceph_osdc_put_request(req);
359 return nr_pages; 359 return nr_pages;
360 360
361 out_pages: 361 out_pages:
362 ceph_unlock_page_vector(pages, nr_pages); 362 ceph_unlock_page_vector(pages, nr_pages);
363 ceph_release_page_vector(pages, nr_pages); 363 ceph_release_page_vector(pages, nr_pages);
364 out: 364 out:
365 ceph_osdc_put_request(req); 365 ceph_osdc_put_request(req);
366 return ret; 366 return ret;
367 } 367 }
368 368
369 369
370 /* 370 /*
371 * Read multiple pages. Leave pages we don't read + unlock in page_list; 371 * Read multiple pages. Leave pages we don't read + unlock in page_list;
372 * the caller (VM) cleans them up. 372 * the caller (VM) cleans them up.
373 */ 373 */
374 static int ceph_readpages(struct file *file, struct address_space *mapping, 374 static int ceph_readpages(struct file *file, struct address_space *mapping,
375 struct list_head *page_list, unsigned nr_pages) 375 struct list_head *page_list, unsigned nr_pages)
376 { 376 {
377 struct inode *inode = file_inode(file); 377 struct inode *inode = file_inode(file);
378 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 378 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
379 int rc = 0; 379 int rc = 0;
380 int max = 0; 380 int max = 0;
381 381
382 rc = ceph_readpages_from_fscache(mapping->host, mapping, page_list, 382 rc = ceph_readpages_from_fscache(mapping->host, mapping, page_list,
383 &nr_pages); 383 &nr_pages);
384 384
385 if (rc == 0) 385 if (rc == 0)
386 goto out; 386 goto out;
387 387
388 if (fsc->mount_options->rsize >= PAGE_CACHE_SIZE) 388 if (fsc->mount_options->rsize >= PAGE_CACHE_SIZE)
389 max = (fsc->mount_options->rsize + PAGE_CACHE_SIZE - 1) 389 max = (fsc->mount_options->rsize + PAGE_CACHE_SIZE - 1)
390 >> PAGE_SHIFT; 390 >> PAGE_SHIFT;
391 391
392 dout("readpages %p file %p nr_pages %d max %d\n", inode, 392 dout("readpages %p file %p nr_pages %d max %d\n", inode,
393 file, nr_pages, 393 file, nr_pages,
394 max); 394 max);
395 while (!list_empty(page_list)) { 395 while (!list_empty(page_list)) {
396 rc = start_read(inode, page_list, max); 396 rc = start_read(inode, page_list, max);
397 if (rc < 0) 397 if (rc < 0)
398 goto out; 398 goto out;
399 BUG_ON(rc == 0); 399 BUG_ON(rc == 0);
400 } 400 }
401 out: 401 out:
402 ceph_fscache_readpages_cancel(inode, page_list); 402 ceph_fscache_readpages_cancel(inode, page_list);
403 403
404 dout("readpages %p file %p ret %d\n", inode, file, rc); 404 dout("readpages %p file %p ret %d\n", inode, file, rc);
405 return rc; 405 return rc;
406 } 406 }
407 407
408 /* 408 /*
409 * Get ref for the oldest snapc for an inode with dirty data... that is, the 409 * Get ref for the oldest snapc for an inode with dirty data... that is, the
410 * only snap context we are allowed to write back. 410 * only snap context we are allowed to write back.
411 */ 411 */
412 static struct ceph_snap_context *get_oldest_context(struct inode *inode, 412 static struct ceph_snap_context *get_oldest_context(struct inode *inode,
413 u64 *snap_size) 413 u64 *snap_size)
414 { 414 {
415 struct ceph_inode_info *ci = ceph_inode(inode); 415 struct ceph_inode_info *ci = ceph_inode(inode);
416 struct ceph_snap_context *snapc = NULL; 416 struct ceph_snap_context *snapc = NULL;
417 struct ceph_cap_snap *capsnap = NULL; 417 struct ceph_cap_snap *capsnap = NULL;
418 418
419 spin_lock(&ci->i_ceph_lock); 419 spin_lock(&ci->i_ceph_lock);
420 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) { 420 list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) {
421 dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap, 421 dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap,
422 capsnap->context, capsnap->dirty_pages); 422 capsnap->context, capsnap->dirty_pages);
423 if (capsnap->dirty_pages) { 423 if (capsnap->dirty_pages) {
424 snapc = ceph_get_snap_context(capsnap->context); 424 snapc = ceph_get_snap_context(capsnap->context);
425 if (snap_size) 425 if (snap_size)
426 *snap_size = capsnap->size; 426 *snap_size = capsnap->size;
427 break; 427 break;
428 } 428 }
429 } 429 }
430 if (!snapc && ci->i_wrbuffer_ref_head) { 430 if (!snapc && ci->i_wrbuffer_ref_head) {
431 snapc = ceph_get_snap_context(ci->i_head_snapc); 431 snapc = ceph_get_snap_context(ci->i_head_snapc);
432 dout(" head snapc %p has %d dirty pages\n", 432 dout(" head snapc %p has %d dirty pages\n",
433 snapc, ci->i_wrbuffer_ref_head); 433 snapc, ci->i_wrbuffer_ref_head);
434 } 434 }
435 spin_unlock(&ci->i_ceph_lock); 435 spin_unlock(&ci->i_ceph_lock);
436 return snapc; 436 return snapc;
437 } 437 }
438 438
439 /* 439 /*
440 * Write a single page, but leave the page locked. 440 * Write a single page, but leave the page locked.
441 * 441 *
442 * If we get a write error, set the page error bit, but still adjust the 442 * If we get a write error, set the page error bit, but still adjust the
443 * dirty page accounting (i.e., page is no longer dirty). 443 * dirty page accounting (i.e., page is no longer dirty).
444 */ 444 */
445 static int writepage_nounlock(struct page *page, struct writeback_control *wbc) 445 static int writepage_nounlock(struct page *page, struct writeback_control *wbc)
446 { 446 {
447 struct inode *inode; 447 struct inode *inode;
448 struct ceph_inode_info *ci; 448 struct ceph_inode_info *ci;
449 struct ceph_fs_client *fsc; 449 struct ceph_fs_client *fsc;
450 struct ceph_osd_client *osdc; 450 struct ceph_osd_client *osdc;
451 struct ceph_snap_context *snapc, *oldest; 451 struct ceph_snap_context *snapc, *oldest;
452 loff_t page_off = page_offset(page); 452 loff_t page_off = page_offset(page);
453 long writeback_stat; 453 long writeback_stat;
454 u64 truncate_size, snap_size = 0; 454 u64 truncate_size, snap_size = 0;
455 u32 truncate_seq; 455 u32 truncate_seq;
456 int err = 0, len = PAGE_CACHE_SIZE; 456 int err = 0, len = PAGE_CACHE_SIZE;
457 457
458 dout("writepage %p idx %lu\n", page, page->index); 458 dout("writepage %p idx %lu\n", page, page->index);
459 459
460 if (!page->mapping || !page->mapping->host) { 460 if (!page->mapping || !page->mapping->host) {
461 dout("writepage %p - no mapping\n", page); 461 dout("writepage %p - no mapping\n", page);
462 return -EFAULT; 462 return -EFAULT;
463 } 463 }
464 inode = page->mapping->host; 464 inode = page->mapping->host;
465 ci = ceph_inode(inode); 465 ci = ceph_inode(inode);
466 fsc = ceph_inode_to_client(inode); 466 fsc = ceph_inode_to_client(inode);
467 osdc = &fsc->client->osdc; 467 osdc = &fsc->client->osdc;
468 468
469 /* verify this is a writeable snap context */ 469 /* verify this is a writeable snap context */
470 snapc = page_snap_context(page); 470 snapc = page_snap_context(page);
471 if (snapc == NULL) { 471 if (snapc == NULL) {
472 dout("writepage %p page %p not dirty?\n", inode, page); 472 dout("writepage %p page %p not dirty?\n", inode, page);
473 goto out; 473 goto out;
474 } 474 }
475 oldest = get_oldest_context(inode, &snap_size); 475 oldest = get_oldest_context(inode, &snap_size);
476 if (snapc->seq > oldest->seq) { 476 if (snapc->seq > oldest->seq) {
477 dout("writepage %p page %p snapc %p not writeable - noop\n", 477 dout("writepage %p page %p snapc %p not writeable - noop\n",
478 inode, page, snapc); 478 inode, page, snapc);
479 /* we should only noop if called by kswapd */ 479 /* we should only noop if called by kswapd */
480 WARN_ON((current->flags & PF_MEMALLOC) == 0); 480 WARN_ON((current->flags & PF_MEMALLOC) == 0);
481 ceph_put_snap_context(oldest); 481 ceph_put_snap_context(oldest);
482 goto out; 482 goto out;
483 } 483 }
484 ceph_put_snap_context(oldest); 484 ceph_put_snap_context(oldest);
485 485
486 spin_lock(&ci->i_ceph_lock); 486 spin_lock(&ci->i_ceph_lock);
487 truncate_seq = ci->i_truncate_seq; 487 truncate_seq = ci->i_truncate_seq;
488 truncate_size = ci->i_truncate_size; 488 truncate_size = ci->i_truncate_size;
489 if (!snap_size) 489 if (!snap_size)
490 snap_size = i_size_read(inode); 490 snap_size = i_size_read(inode);
491 spin_unlock(&ci->i_ceph_lock); 491 spin_unlock(&ci->i_ceph_lock);
492 492
493 /* is this a partial page at end of file? */ 493 /* is this a partial page at end of file? */
494 if (page_off >= snap_size) { 494 if (page_off >= snap_size) {
495 dout("%p page eof %llu\n", page, snap_size); 495 dout("%p page eof %llu\n", page, snap_size);
496 goto out; 496 goto out;
497 } 497 }
498 if (snap_size < page_off + len) 498 if (snap_size < page_off + len)
499 len = snap_size - page_off; 499 len = snap_size - page_off;
500 500
501 dout("writepage %p page %p index %lu on %llu~%u snapc %p\n", 501 dout("writepage %p page %p index %lu on %llu~%u snapc %p\n",
502 inode, page, page->index, page_off, len, snapc); 502 inode, page, page->index, page_off, len, snapc);
503 503
504 writeback_stat = atomic_long_inc_return(&fsc->writeback_count); 504 writeback_stat = atomic_long_inc_return(&fsc->writeback_count);
505 if (writeback_stat > 505 if (writeback_stat >
506 CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb)) 506 CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb))
507 set_bdi_congested(&fsc->backing_dev_info, BLK_RW_ASYNC); 507 set_bdi_congested(&fsc->backing_dev_info, BLK_RW_ASYNC);
508 508
509 ceph_readpage_to_fscache(inode, page); 509 ceph_readpage_to_fscache(inode, page);
510 510
511 set_page_writeback(page); 511 set_page_writeback(page);
512 err = ceph_osdc_writepages(osdc, ceph_vino(inode), 512 err = ceph_osdc_writepages(osdc, ceph_vino(inode),
513 &ci->i_layout, snapc, 513 &ci->i_layout, snapc,
514 page_off, len, 514 page_off, len,
515 truncate_seq, truncate_size, 515 truncate_seq, truncate_size,
516 &inode->i_mtime, &page, 1); 516 &inode->i_mtime, &page, 1);
517 if (err < 0) { 517 if (err < 0) {
518 dout("writepage setting page/mapping error %d %p\n", err, page); 518 dout("writepage setting page/mapping error %d %p\n", err, page);
519 SetPageError(page); 519 SetPageError(page);
520 mapping_set_error(&inode->i_data, err); 520 mapping_set_error(&inode->i_data, err);
521 if (wbc) 521 if (wbc)
522 wbc->pages_skipped++; 522 wbc->pages_skipped++;
523 } else { 523 } else {
524 dout("writepage cleaned page %p\n", page); 524 dout("writepage cleaned page %p\n", page);
525 err = 0; /* vfs expects us to return 0 */ 525 err = 0; /* vfs expects us to return 0 */
526 } 526 }
527 page->private = 0; 527 page->private = 0;
528 ClearPagePrivate(page); 528 ClearPagePrivate(page);
529 end_page_writeback(page); 529 end_page_writeback(page);
530 ceph_put_wrbuffer_cap_refs(ci, 1, snapc); 530 ceph_put_wrbuffer_cap_refs(ci, 1, snapc);
531 ceph_put_snap_context(snapc); /* page's reference */ 531 ceph_put_snap_context(snapc); /* page's reference */
532 out: 532 out:
533 return err; 533 return err;
534 } 534 }
535 535
536 static int ceph_writepage(struct page *page, struct writeback_control *wbc) 536 static int ceph_writepage(struct page *page, struct writeback_control *wbc)
537 { 537 {
538 int err; 538 int err;
539 struct inode *inode = page->mapping->host; 539 struct inode *inode = page->mapping->host;
540 BUG_ON(!inode); 540 BUG_ON(!inode);
541 ihold(inode); 541 ihold(inode);
542 err = writepage_nounlock(page, wbc); 542 err = writepage_nounlock(page, wbc);
543 unlock_page(page); 543 unlock_page(page);
544 iput(inode); 544 iput(inode);
545 return err; 545 return err;
546 } 546 }
547 547
548 548
549 /* 549 /*
550 * lame release_pages helper. release_pages() isn't exported to 550 * lame release_pages helper. release_pages() isn't exported to
551 * modules. 551 * modules.
552 */ 552 */
553 static void ceph_release_pages(struct page **pages, int num) 553 static void ceph_release_pages(struct page **pages, int num)
554 { 554 {
555 struct pagevec pvec; 555 struct pagevec pvec;
556 int i; 556 int i;
557 557
558 pagevec_init(&pvec, 0); 558 pagevec_init(&pvec, 0);
559 for (i = 0; i < num; i++) { 559 for (i = 0; i < num; i++) {
560 if (pagevec_add(&pvec, pages[i]) == 0) 560 if (pagevec_add(&pvec, pages[i]) == 0)
561 pagevec_release(&pvec); 561 pagevec_release(&pvec);
562 } 562 }
563 pagevec_release(&pvec); 563 pagevec_release(&pvec);
564 } 564 }
565 565
566 /* 566 /*
567 * async writeback completion handler. 567 * async writeback completion handler.
568 * 568 *
569 * If we get an error, set the mapping error bit, but not the individual 569 * If we get an error, set the mapping error bit, but not the individual
570 * page error bits. 570 * page error bits.
571 */ 571 */
572 static void writepages_finish(struct ceph_osd_request *req, 572 static void writepages_finish(struct ceph_osd_request *req,
573 struct ceph_msg *msg) 573 struct ceph_msg *msg)
574 { 574 {
575 struct inode *inode = req->r_inode; 575 struct inode *inode = req->r_inode;
576 struct ceph_inode_info *ci = ceph_inode(inode); 576 struct ceph_inode_info *ci = ceph_inode(inode);
577 struct ceph_osd_data *osd_data; 577 struct ceph_osd_data *osd_data;
578 unsigned wrote; 578 unsigned wrote;
579 struct page *page; 579 struct page *page;
580 int num_pages; 580 int num_pages;
581 int i; 581 int i;
582 struct ceph_snap_context *snapc = req->r_snapc; 582 struct ceph_snap_context *snapc = req->r_snapc;
583 struct address_space *mapping = inode->i_mapping; 583 struct address_space *mapping = inode->i_mapping;
584 int rc = req->r_result; 584 int rc = req->r_result;
585 u64 bytes = req->r_ops[0].extent.length; 585 u64 bytes = req->r_ops[0].extent.length;
586 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 586 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
587 long writeback_stat; 587 long writeback_stat;
588 unsigned issued = ceph_caps_issued(ci); 588 unsigned issued = ceph_caps_issued(ci);
589 589
590 osd_data = osd_req_op_extent_osd_data(req, 0); 590 osd_data = osd_req_op_extent_osd_data(req, 0);
591 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES); 591 BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
592 num_pages = calc_pages_for((u64)osd_data->alignment, 592 num_pages = calc_pages_for((u64)osd_data->alignment,
593 (u64)osd_data->length); 593 (u64)osd_data->length);
594 if (rc >= 0) { 594 if (rc >= 0) {
595 /* 595 /*
596 * Assume we wrote the pages we originally sent. The 596 * Assume we wrote the pages we originally sent. The
597 * osd might reply with fewer pages if our writeback 597 * osd might reply with fewer pages if our writeback
598 * raced with a truncation and was adjusted at the osd, 598 * raced with a truncation and was adjusted at the osd,
599 * so don't believe the reply. 599 * so don't believe the reply.
600 */ 600 */
601 wrote = num_pages; 601 wrote = num_pages;
602 } else { 602 } else {
603 wrote = 0; 603 wrote = 0;
604 mapping_set_error(mapping, rc); 604 mapping_set_error(mapping, rc);
605 } 605 }
606 dout("writepages_finish %p rc %d bytes %llu wrote %d (pages)\n", 606 dout("writepages_finish %p rc %d bytes %llu wrote %d (pages)\n",
607 inode, rc, bytes, wrote); 607 inode, rc, bytes, wrote);
608 608
609 /* clean all pages */ 609 /* clean all pages */
610 for (i = 0; i < num_pages; i++) { 610 for (i = 0; i < num_pages; i++) {
611 page = osd_data->pages[i]; 611 page = osd_data->pages[i];
612 BUG_ON(!page); 612 BUG_ON(!page);
613 WARN_ON(!PageUptodate(page)); 613 WARN_ON(!PageUptodate(page));
614 614
615 writeback_stat = 615 writeback_stat =
616 atomic_long_dec_return(&fsc->writeback_count); 616 atomic_long_dec_return(&fsc->writeback_count);
617 if (writeback_stat < 617 if (writeback_stat <
618 CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb)) 618 CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb))
619 clear_bdi_congested(&fsc->backing_dev_info, 619 clear_bdi_congested(&fsc->backing_dev_info,
620 BLK_RW_ASYNC); 620 BLK_RW_ASYNC);
621 621
622 ceph_put_snap_context(page_snap_context(page)); 622 ceph_put_snap_context(page_snap_context(page));
623 page->private = 0; 623 page->private = 0;
624 ClearPagePrivate(page); 624 ClearPagePrivate(page);
625 dout("unlocking %d %p\n", i, page); 625 dout("unlocking %d %p\n", i, page);
626 end_page_writeback(page); 626 end_page_writeback(page);
627 627
628 /* 628 /*
629 * We lost the cache cap, need to truncate the page before 629 * We lost the cache cap, need to truncate the page before
630 * it is unlocked, otherwise we'd truncate it later in the 630 * it is unlocked, otherwise we'd truncate it later in the
631 * page truncation thread, possibly losing some data that 631 * page truncation thread, possibly losing some data that
632 * raced its way in 632 * raced its way in
633 */ 633 */
634 if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0) 634 if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0)
635 generic_error_remove_page(inode->i_mapping, page); 635 generic_error_remove_page(inode->i_mapping, page);
636 636
637 unlock_page(page); 637 unlock_page(page);
638 } 638 }
639 dout("%p wrote+cleaned %d pages\n", inode, wrote); 639 dout("%p wrote+cleaned %d pages\n", inode, wrote);
640 ceph_put_wrbuffer_cap_refs(ci, num_pages, snapc); 640 ceph_put_wrbuffer_cap_refs(ci, num_pages, snapc);
641 641
642 ceph_release_pages(osd_data->pages, num_pages); 642 ceph_release_pages(osd_data->pages, num_pages);
643 if (osd_data->pages_from_pool) 643 if (osd_data->pages_from_pool)
644 mempool_free(osd_data->pages, 644 mempool_free(osd_data->pages,
645 ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool); 645 ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool);
646 else 646 else
647 kfree(osd_data->pages); 647 kfree(osd_data->pages);
648 ceph_osdc_put_request(req); 648 ceph_osdc_put_request(req);
649 } 649 }
650 650
651 /* 651 /*
652 * initiate async writeback 652 * initiate async writeback
653 */ 653 */
654 static int ceph_writepages_start(struct address_space *mapping, 654 static int ceph_writepages_start(struct address_space *mapping,
655 struct writeback_control *wbc) 655 struct writeback_control *wbc)
656 { 656 {
657 struct inode *inode = mapping->host; 657 struct inode *inode = mapping->host;
658 struct ceph_inode_info *ci = ceph_inode(inode); 658 struct ceph_inode_info *ci = ceph_inode(inode);
659 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 659 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
660 struct ceph_vino vino = ceph_vino(inode); 660 struct ceph_vino vino = ceph_vino(inode);
661 pgoff_t index, start, end; 661 pgoff_t index, start, end;
662 int range_whole = 0; 662 int range_whole = 0;
663 int should_loop = 1; 663 int should_loop = 1;
664 pgoff_t max_pages = 0, max_pages_ever = 0; 664 pgoff_t max_pages = 0, max_pages_ever = 0;
665 struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc; 665 struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc;
666 struct pagevec pvec; 666 struct pagevec pvec;
667 int done = 0; 667 int done = 0;
668 int rc = 0; 668 int rc = 0;
669 unsigned wsize = 1 << inode->i_blkbits; 669 unsigned wsize = 1 << inode->i_blkbits;
670 struct ceph_osd_request *req = NULL; 670 struct ceph_osd_request *req = NULL;
671 int do_sync; 671 int do_sync;
672 u64 truncate_size, snap_size; 672 u64 truncate_size, snap_size;
673 u32 truncate_seq; 673 u32 truncate_seq;
674 674
675 /* 675 /*
676 * Include a 'sync' in the OSD request if this is a data 676 * Include a 'sync' in the OSD request if this is a data
677 * integrity write (e.g., O_SYNC write or fsync()), or if our 677 * integrity write (e.g., O_SYNC write or fsync()), or if our
678 * cap is being revoked. 678 * cap is being revoked.
679 */ 679 */
680 if ((wbc->sync_mode == WB_SYNC_ALL) || 680 if ((wbc->sync_mode == WB_SYNC_ALL) ||
681 ceph_caps_revoking(ci, CEPH_CAP_FILE_BUFFER)) 681 ceph_caps_revoking(ci, CEPH_CAP_FILE_BUFFER))
682 do_sync = 1; 682 do_sync = 1;
683 dout("writepages_start %p dosync=%d (mode=%s)\n", 683 dout("writepages_start %p dosync=%d (mode=%s)\n",
684 inode, do_sync, 684 inode, do_sync,
685 wbc->sync_mode == WB_SYNC_NONE ? "NONE" : 685 wbc->sync_mode == WB_SYNC_NONE ? "NONE" :
686 (wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD")); 686 (wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD"));
687 687
688 if (fsc->mount_state == CEPH_MOUNT_SHUTDOWN) { 688 if (fsc->mount_state == CEPH_MOUNT_SHUTDOWN) {
689 pr_warning("writepage_start %p on forced umount\n", inode); 689 pr_warning("writepage_start %p on forced umount\n", inode);
690 return -EIO; /* we're in a forced umount, don't write! */ 690 return -EIO; /* we're in a forced umount, don't write! */
691 } 691 }
692 if (fsc->mount_options->wsize && fsc->mount_options->wsize < wsize) 692 if (fsc->mount_options->wsize && fsc->mount_options->wsize < wsize)
693 wsize = fsc->mount_options->wsize; 693 wsize = fsc->mount_options->wsize;
694 if (wsize < PAGE_CACHE_SIZE) 694 if (wsize < PAGE_CACHE_SIZE)
695 wsize = PAGE_CACHE_SIZE; 695 wsize = PAGE_CACHE_SIZE;
696 max_pages_ever = wsize >> PAGE_CACHE_SHIFT; 696 max_pages_ever = wsize >> PAGE_CACHE_SHIFT;
697 697
698 pagevec_init(&pvec, 0); 698 pagevec_init(&pvec, 0);
699 699
700 /* where to start/end? */ 700 /* where to start/end? */
701 if (wbc->range_cyclic) { 701 if (wbc->range_cyclic) {
702 start = mapping->writeback_index; /* Start from prev offset */ 702 start = mapping->writeback_index; /* Start from prev offset */
703 end = -1; 703 end = -1;
704 dout(" cyclic, start at %lu\n", start); 704 dout(" cyclic, start at %lu\n", start);
705 } else { 705 } else {
706 start = wbc->range_start >> PAGE_CACHE_SHIFT; 706 start = wbc->range_start >> PAGE_CACHE_SHIFT;
707 end = wbc->range_end >> PAGE_CACHE_SHIFT; 707 end = wbc->range_end >> PAGE_CACHE_SHIFT;
708 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) 708 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
709 range_whole = 1; 709 range_whole = 1;
710 should_loop = 0; 710 should_loop = 0;
711 dout(" not cyclic, %lu to %lu\n", start, end); 711 dout(" not cyclic, %lu to %lu\n", start, end);
712 } 712 }
713 index = start; 713 index = start;
714 714
715 retry: 715 retry:
716 /* find oldest snap context with dirty data */ 716 /* find oldest snap context with dirty data */
717 ceph_put_snap_context(snapc); 717 ceph_put_snap_context(snapc);
718 snap_size = 0; 718 snap_size = 0;
719 snapc = get_oldest_context(inode, &snap_size); 719 snapc = get_oldest_context(inode, &snap_size);
720 if (!snapc) { 720 if (!snapc) {
721 /* hmm, why does writepages get called when there 721 /* hmm, why does writepages get called when there
722 is no dirty data? */ 722 is no dirty data? */
723 dout(" no snap context with dirty data?\n"); 723 dout(" no snap context with dirty data?\n");
724 goto out; 724 goto out;
725 } 725 }
726 if (snap_size == 0) 726 if (snap_size == 0)
727 snap_size = i_size_read(inode); 727 snap_size = i_size_read(inode);
728 dout(" oldest snapc is %p seq %lld (%d snaps)\n", 728 dout(" oldest snapc is %p seq %lld (%d snaps)\n",
729 snapc, snapc->seq, snapc->num_snaps); 729 snapc, snapc->seq, snapc->num_snaps);
730 730
731 spin_lock(&ci->i_ceph_lock); 731 spin_lock(&ci->i_ceph_lock);
732 truncate_seq = ci->i_truncate_seq; 732 truncate_seq = ci->i_truncate_seq;
733 truncate_size = ci->i_truncate_size; 733 truncate_size = ci->i_truncate_size;
734 if (!snap_size) 734 if (!snap_size)
735 snap_size = i_size_read(inode); 735 snap_size = i_size_read(inode);
736 spin_unlock(&ci->i_ceph_lock); 736 spin_unlock(&ci->i_ceph_lock);
737 737
738 if (last_snapc && snapc != last_snapc) { 738 if (last_snapc && snapc != last_snapc) {
739 /* if we switched to a newer snapc, restart our scan at the 739 /* if we switched to a newer snapc, restart our scan at the
740 * start of the original file range. */ 740 * start of the original file range. */
741 dout(" snapc differs from last pass, restarting at %lu\n", 741 dout(" snapc differs from last pass, restarting at %lu\n",
742 index); 742 index);
743 index = start; 743 index = start;
744 } 744 }
745 last_snapc = snapc; 745 last_snapc = snapc;
746 746
747 while (!done && index <= end) { 747 while (!done && index <= end) {
748 int num_ops = do_sync ? 2 : 1; 748 int num_ops = do_sync ? 2 : 1;
749 unsigned i; 749 unsigned i;
750 int first; 750 int first;
751 pgoff_t next; 751 pgoff_t next;
752 int pvec_pages, locked_pages; 752 int pvec_pages, locked_pages;
753 struct page **pages = NULL; 753 struct page **pages = NULL;
754 mempool_t *pool = NULL; /* Becomes non-null if mempool used */ 754 mempool_t *pool = NULL; /* Becomes non-null if mempool used */
755 struct page *page; 755 struct page *page;
756 int want; 756 int want;
757 u64 offset, len; 757 u64 offset, len;
758 long writeback_stat; 758 long writeback_stat;
759 759
760 next = 0; 760 next = 0;
761 locked_pages = 0; 761 locked_pages = 0;
762 max_pages = max_pages_ever; 762 max_pages = max_pages_ever;
763 763
764 get_more_pages: 764 get_more_pages:
765 first = -1; 765 first = -1;
766 want = min(end - index, 766 want = min(end - index,
767 min((pgoff_t)PAGEVEC_SIZE, 767 min((pgoff_t)PAGEVEC_SIZE,
768 max_pages - (pgoff_t)locked_pages) - 1) 768 max_pages - (pgoff_t)locked_pages) - 1)
769 + 1; 769 + 1;
770 pvec_pages = pagevec_lookup_tag(&pvec, mapping, &index, 770 pvec_pages = pagevec_lookup_tag(&pvec, mapping, &index,
771 PAGECACHE_TAG_DIRTY, 771 PAGECACHE_TAG_DIRTY,
772 want); 772 want);
773 dout("pagevec_lookup_tag got %d\n", pvec_pages); 773 dout("pagevec_lookup_tag got %d\n", pvec_pages);
774 if (!pvec_pages && !locked_pages) 774 if (!pvec_pages && !locked_pages)
775 break; 775 break;
776 for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) { 776 for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) {
777 page = pvec.pages[i]; 777 page = pvec.pages[i];
778 dout("? %p idx %lu\n", page, page->index); 778 dout("? %p idx %lu\n", page, page->index);
779 if (locked_pages == 0) 779 if (locked_pages == 0)
780 lock_page(page); /* first page */ 780 lock_page(page); /* first page */
781 else if (!trylock_page(page)) 781 else if (!trylock_page(page))
782 break; 782 break;
783 783
784 /* only dirty pages, or our accounting breaks */ 784 /* only dirty pages, or our accounting breaks */
785 if (unlikely(!PageDirty(page)) || 785 if (unlikely(!PageDirty(page)) ||
786 unlikely(page->mapping != mapping)) { 786 unlikely(page->mapping != mapping)) {
787 dout("!dirty or !mapping %p\n", page); 787 dout("!dirty or !mapping %p\n", page);
788 unlock_page(page); 788 unlock_page(page);
789 break; 789 break;
790 } 790 }
791 if (!wbc->range_cyclic && page->index > end) { 791 if (!wbc->range_cyclic && page->index > end) {
792 dout("end of range %p\n", page); 792 dout("end of range %p\n", page);
793 done = 1; 793 done = 1;
794 unlock_page(page); 794 unlock_page(page);
795 break; 795 break;
796 } 796 }
797 if (next && (page->index != next)) { 797 if (next && (page->index != next)) {
798 dout("not consecutive %p\n", page); 798 dout("not consecutive %p\n", page);
799 unlock_page(page); 799 unlock_page(page);
800 break; 800 break;
801 } 801 }
802 if (wbc->sync_mode != WB_SYNC_NONE) { 802 if (wbc->sync_mode != WB_SYNC_NONE) {
803 dout("waiting on writeback %p\n", page); 803 dout("waiting on writeback %p\n", page);
804 wait_on_page_writeback(page); 804 wait_on_page_writeback(page);
805 } 805 }
806 if (page_offset(page) >= snap_size) { 806 if (page_offset(page) >= snap_size) {
807 dout("%p page eof %llu\n", page, snap_size); 807 dout("%p page eof %llu\n", page, snap_size);
808 done = 1; 808 done = 1;
809 unlock_page(page); 809 unlock_page(page);
810 break; 810 break;
811 } 811 }
812 if (PageWriteback(page)) { 812 if (PageWriteback(page)) {
813 dout("%p under writeback\n", page); 813 dout("%p under writeback\n", page);
814 unlock_page(page); 814 unlock_page(page);
815 break; 815 break;
816 } 816 }
817 817
818 /* only if matching snap context */ 818 /* only if matching snap context */
819 pgsnapc = page_snap_context(page); 819 pgsnapc = page_snap_context(page);
820 if (pgsnapc->seq > snapc->seq) { 820 if (pgsnapc->seq > snapc->seq) {
821 dout("page snapc %p %lld > oldest %p %lld\n", 821 dout("page snapc %p %lld > oldest %p %lld\n",
822 pgsnapc, pgsnapc->seq, snapc, snapc->seq); 822 pgsnapc, pgsnapc->seq, snapc, snapc->seq);
823 unlock_page(page); 823 unlock_page(page);
824 if (!locked_pages) 824 if (!locked_pages)
825 continue; /* keep looking for snap */ 825 continue; /* keep looking for snap */
826 break; 826 break;
827 } 827 }
828 828
829 if (!clear_page_dirty_for_io(page)) { 829 if (!clear_page_dirty_for_io(page)) {
830 dout("%p !clear_page_dirty_for_io\n", page); 830 dout("%p !clear_page_dirty_for_io\n", page);
831 unlock_page(page); 831 unlock_page(page);
832 break; 832 break;
833 } 833 }
834 834
835 /* 835 /*
836 * We have something to write. If this is 836 * We have something to write. If this is
837 * the first locked page this time through, 837 * the first locked page this time through,
838 * allocate an osd request and a page array 838 * allocate an osd request and a page array
839 * that it will use. 839 * that it will use.
840 */ 840 */
841 if (locked_pages == 0) { 841 if (locked_pages == 0) {
842 BUG_ON(pages); 842 BUG_ON(pages);
843 /* prepare async write request */ 843 /* prepare async write request */
844 offset = (u64)page_offset(page); 844 offset = (u64)page_offset(page);
845 len = wsize; 845 len = wsize;
846 req = ceph_osdc_new_request(&fsc->client->osdc, 846 req = ceph_osdc_new_request(&fsc->client->osdc,
847 &ci->i_layout, vino, 847 &ci->i_layout, vino,
848 offset, &len, num_ops, 848 offset, &len, num_ops,
849 CEPH_OSD_OP_WRITE, 849 CEPH_OSD_OP_WRITE,
850 CEPH_OSD_FLAG_WRITE | 850 CEPH_OSD_FLAG_WRITE |
851 CEPH_OSD_FLAG_ONDISK, 851 CEPH_OSD_FLAG_ONDISK,
852 snapc, truncate_seq, 852 snapc, truncate_seq,
853 truncate_size, true); 853 truncate_size, true);
854 if (IS_ERR(req)) { 854 if (IS_ERR(req)) {
855 rc = PTR_ERR(req); 855 rc = PTR_ERR(req);
856 unlock_page(page); 856 unlock_page(page);
857 break; 857 break;
858 } 858 }
859 859
860 req->r_callback = writepages_finish; 860 req->r_callback = writepages_finish;
861 req->r_inode = inode; 861 req->r_inode = inode;
862 862
863 max_pages = calc_pages_for(0, (u64)len); 863 max_pages = calc_pages_for(0, (u64)len);
864 pages = kmalloc(max_pages * sizeof (*pages), 864 pages = kmalloc(max_pages * sizeof (*pages),
865 GFP_NOFS); 865 GFP_NOFS);
866 if (!pages) { 866 if (!pages) {
867 pool = fsc->wb_pagevec_pool; 867 pool = fsc->wb_pagevec_pool;
868 pages = mempool_alloc(pool, GFP_NOFS); 868 pages = mempool_alloc(pool, GFP_NOFS);
869 BUG_ON(!pages); 869 BUG_ON(!pages);
870 } 870 }
871 } 871 }
872 872
873 /* note position of first page in pvec */ 873 /* note position of first page in pvec */
874 if (first < 0) 874 if (first < 0)
875 first = i; 875 first = i;
876 dout("%p will write page %p idx %lu\n", 876 dout("%p will write page %p idx %lu\n",
877 inode, page, page->index); 877 inode, page, page->index);
878 878
879 writeback_stat = 879 writeback_stat =
880 atomic_long_inc_return(&fsc->writeback_count); 880 atomic_long_inc_return(&fsc->writeback_count);
881 if (writeback_stat > CONGESTION_ON_THRESH( 881 if (writeback_stat > CONGESTION_ON_THRESH(
882 fsc->mount_options->congestion_kb)) { 882 fsc->mount_options->congestion_kb)) {
883 set_bdi_congested(&fsc->backing_dev_info, 883 set_bdi_congested(&fsc->backing_dev_info,
884 BLK_RW_ASYNC); 884 BLK_RW_ASYNC);
885 } 885 }
886 886
887 set_page_writeback(page); 887 set_page_writeback(page);
888 pages[locked_pages] = page; 888 pages[locked_pages] = page;
889 locked_pages++; 889 locked_pages++;
890 next = page->index + 1; 890 next = page->index + 1;
891 } 891 }
892 892
893 /* did we get anything? */ 893 /* did we get anything? */
894 if (!locked_pages) 894 if (!locked_pages)
895 goto release_pvec_pages; 895 goto release_pvec_pages;
896 if (i) { 896 if (i) {
897 int j; 897 int j;
898 BUG_ON(!locked_pages || first < 0); 898 BUG_ON(!locked_pages || first < 0);
899 899
900 if (pvec_pages && i == pvec_pages && 900 if (pvec_pages && i == pvec_pages &&
901 locked_pages < max_pages) { 901 locked_pages < max_pages) {
902 dout("reached end pvec, trying for more\n"); 902 dout("reached end pvec, trying for more\n");
903 pagevec_reinit(&pvec); 903 pagevec_reinit(&pvec);
904 goto get_more_pages; 904 goto get_more_pages;
905 } 905 }
906 906
907 /* shift unused pages over in the pvec... we 907 /* shift unused pages over in the pvec... we
908 * will need to release them below. */ 908 * will need to release them below. */
909 for (j = i; j < pvec_pages; j++) { 909 for (j = i; j < pvec_pages; j++) {
910 dout(" pvec leftover page %p\n", 910 dout(" pvec leftover page %p\n",
911 pvec.pages[j]); 911 pvec.pages[j]);
912 pvec.pages[j-i+first] = pvec.pages[j]; 912 pvec.pages[j-i+first] = pvec.pages[j];
913 } 913 }
914 pvec.nr -= i-first; 914 pvec.nr -= i-first;
915 } 915 }
916 916
917 /* Format the osd request message and submit the write */ 917 /* Format the osd request message and submit the write */
918 918
919 offset = page_offset(pages[0]); 919 offset = page_offset(pages[0]);
920 len = min(snap_size - offset, 920 len = min(snap_size - offset,
921 (u64)locked_pages << PAGE_CACHE_SHIFT); 921 (u64)locked_pages << PAGE_CACHE_SHIFT);
922 dout("writepages got %d pages at %llu~%llu\n", 922 dout("writepages got %d pages at %llu~%llu\n",
923 locked_pages, offset, len); 923 locked_pages, offset, len);
924 924
925 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, 925 osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
926 !!pool, false); 926 !!pool, false);
927 927
928 pages = NULL; /* request message now owns the pages array */ 928 pages = NULL; /* request message now owns the pages array */
929 pool = NULL; 929 pool = NULL;
930 930
931 /* Update the write op length in case we changed it */ 931 /* Update the write op length in case we changed it */
932 932
933 osd_req_op_extent_update(req, 0, len); 933 osd_req_op_extent_update(req, 0, len);
934 934
935 vino = ceph_vino(inode); 935 vino = ceph_vino(inode);
936 ceph_osdc_build_request(req, offset, snapc, vino.snap, 936 ceph_osdc_build_request(req, offset, snapc, vino.snap,
937 &inode->i_mtime); 937 &inode->i_mtime);
938 938
939 rc = ceph_osdc_start_request(&fsc->client->osdc, req, true); 939 rc = ceph_osdc_start_request(&fsc->client->osdc, req, true);
940 BUG_ON(rc); 940 BUG_ON(rc);
941 req = NULL; 941 req = NULL;
942 942
943 /* continue? */ 943 /* continue? */
944 index = next; 944 index = next;
945 wbc->nr_to_write -= locked_pages; 945 wbc->nr_to_write -= locked_pages;
946 if (wbc->nr_to_write <= 0) 946 if (wbc->nr_to_write <= 0)
947 done = 1; 947 done = 1;
948 948
949 release_pvec_pages: 949 release_pvec_pages:
950 dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr, 950 dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr,
951 pvec.nr ? pvec.pages[0] : NULL); 951 pvec.nr ? pvec.pages[0] : NULL);
952 pagevec_release(&pvec); 952 pagevec_release(&pvec);
953 953
954 if (locked_pages && !done) 954 if (locked_pages && !done)
955 goto retry; 955 goto retry;
956 } 956 }
957 957
958 if (should_loop && !done) { 958 if (should_loop && !done) {
959 /* more to do; loop back to beginning of file */ 959 /* more to do; loop back to beginning of file */
960 dout("writepages looping back to beginning of file\n"); 960 dout("writepages looping back to beginning of file\n");
961 should_loop = 0; 961 should_loop = 0;
962 index = 0; 962 index = 0;
963 goto retry; 963 goto retry;
964 } 964 }
965 965
966 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) 966 if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
967 mapping->writeback_index = index; 967 mapping->writeback_index = index;
968 968
969 out: 969 out:
970 if (req) 970 if (req)
971 ceph_osdc_put_request(req); 971 ceph_osdc_put_request(req);
972 ceph_put_snap_context(snapc); 972 ceph_put_snap_context(snapc);
973 dout("writepages done, rc = %d\n", rc); 973 dout("writepages done, rc = %d\n", rc);
974 return rc; 974 return rc;
975 } 975 }
976 976
977 977
978 978
979 /* 979 /*
980 * See if a given @snapc is either writeable, or already written. 980 * See if a given @snapc is either writeable, or already written.
981 */ 981 */
982 static int context_is_writeable_or_written(struct inode *inode, 982 static int context_is_writeable_or_written(struct inode *inode,
983 struct ceph_snap_context *snapc) 983 struct ceph_snap_context *snapc)
984 { 984 {
985 struct ceph_snap_context *oldest = get_oldest_context(inode, NULL); 985 struct ceph_snap_context *oldest = get_oldest_context(inode, NULL);
986 int ret = !oldest || snapc->seq <= oldest->seq; 986 int ret = !oldest || snapc->seq <= oldest->seq;
987 987
988 ceph_put_snap_context(oldest); 988 ceph_put_snap_context(oldest);
989 return ret; 989 return ret;
990 } 990 }
991 991
992 /* 992 /*
993 * We are only allowed to write into/dirty the page if the page is 993 * We are only allowed to write into/dirty the page if the page is
994 * clean, or already dirty within the same snap context. 994 * clean, or already dirty within the same snap context.
995 * 995 *
996 * called with page locked. 996 * called with page locked.
997 * return success with page locked, 997 * return success with page locked,
998 * or any failure (incl -EAGAIN) with page unlocked. 998 * or any failure (incl -EAGAIN) with page unlocked.
999 */ 999 */
1000 static int ceph_update_writeable_page(struct file *file, 1000 static int ceph_update_writeable_page(struct file *file,
1001 loff_t pos, unsigned len, 1001 loff_t pos, unsigned len,
1002 struct page *page) 1002 struct page *page)
1003 { 1003 {
1004 struct inode *inode = file_inode(file); 1004 struct inode *inode = file_inode(file);
1005 struct ceph_inode_info *ci = ceph_inode(inode); 1005 struct ceph_inode_info *ci = ceph_inode(inode);
1006 struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc; 1006 struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1007 loff_t page_off = pos & PAGE_CACHE_MASK; 1007 loff_t page_off = pos & PAGE_CACHE_MASK;
1008 int pos_in_page = pos & ~PAGE_CACHE_MASK; 1008 int pos_in_page = pos & ~PAGE_CACHE_MASK;
1009 int end_in_page = pos_in_page + len; 1009 int end_in_page = pos_in_page + len;
1010 loff_t i_size; 1010 loff_t i_size;
1011 int r; 1011 int r;
1012 struct ceph_snap_context *snapc, *oldest; 1012 struct ceph_snap_context *snapc, *oldest;
1013 1013
1014 retry_locked: 1014 retry_locked:
1015 /* writepages currently holds page lock, but if we change that later, */ 1015 /* writepages currently holds page lock, but if we change that later, */
1016 wait_on_page_writeback(page); 1016 wait_on_page_writeback(page);
1017 1017
1018 /* check snap context */ 1018 /* check snap context */
1019 BUG_ON(!ci->i_snap_realm); 1019 BUG_ON(!ci->i_snap_realm);
1020 down_read(&mdsc->snap_rwsem); 1020 down_read(&mdsc->snap_rwsem);
1021 BUG_ON(!ci->i_snap_realm->cached_context); 1021 BUG_ON(!ci->i_snap_realm->cached_context);
1022 snapc = page_snap_context(page); 1022 snapc = page_snap_context(page);
1023 if (snapc && snapc != ci->i_head_snapc) { 1023 if (snapc && snapc != ci->i_head_snapc) {
1024 /* 1024 /*
1025 * this page is already dirty in another (older) snap 1025 * this page is already dirty in another (older) snap
1026 * context! is it writeable now? 1026 * context! is it writeable now?
1027 */ 1027 */
1028 oldest = get_oldest_context(inode, NULL); 1028 oldest = get_oldest_context(inode, NULL);
1029 up_read(&mdsc->snap_rwsem); 1029 up_read(&mdsc->snap_rwsem);
1030 1030
1031 if (snapc->seq > oldest->seq) { 1031 if (snapc->seq > oldest->seq) {
1032 ceph_put_snap_context(oldest); 1032 ceph_put_snap_context(oldest);
1033 dout(" page %p snapc %p not current or oldest\n", 1033 dout(" page %p snapc %p not current or oldest\n",
1034 page, snapc); 1034 page, snapc);
1035 /* 1035 /*
1036 * queue for writeback, and wait for snapc to 1036 * queue for writeback, and wait for snapc to
1037 * be writeable or written 1037 * be writeable or written
1038 */ 1038 */
1039 snapc = ceph_get_snap_context(snapc); 1039 snapc = ceph_get_snap_context(snapc);
1040 unlock_page(page); 1040 unlock_page(page);
1041 ceph_queue_writeback(inode); 1041 ceph_queue_writeback(inode);
1042 r = wait_event_interruptible(ci->i_cap_wq, 1042 r = wait_event_interruptible(ci->i_cap_wq,
1043 context_is_writeable_or_written(inode, snapc)); 1043 context_is_writeable_or_written(inode, snapc));
1044 ceph_put_snap_context(snapc); 1044 ceph_put_snap_context(snapc);
1045 if (r == -ERESTARTSYS) 1045 if (r == -ERESTARTSYS)
1046 return r; 1046 return r;
1047 return -EAGAIN; 1047 return -EAGAIN;
1048 } 1048 }
1049 ceph_put_snap_context(oldest); 1049 ceph_put_snap_context(oldest);
1050 1050
1051 /* yay, writeable, do it now (without dropping page lock) */ 1051 /* yay, writeable, do it now (without dropping page lock) */
1052 dout(" page %p snapc %p not current, but oldest\n", 1052 dout(" page %p snapc %p not current, but oldest\n",
1053 page, snapc); 1053 page, snapc);
1054 if (!clear_page_dirty_for_io(page)) 1054 if (!clear_page_dirty_for_io(page))
1055 goto retry_locked; 1055 goto retry_locked;
1056 r = writepage_nounlock(page, NULL); 1056 r = writepage_nounlock(page, NULL);
1057 if (r < 0) 1057 if (r < 0)
1058 goto fail_nosnap; 1058 goto fail_nosnap;
1059 goto retry_locked; 1059 goto retry_locked;
1060 } 1060 }
1061 1061
1062 if (PageUptodate(page)) { 1062 if (PageUptodate(page)) {
1063 dout(" page %p already uptodate\n", page); 1063 dout(" page %p already uptodate\n", page);
1064 return 0; 1064 return 0;
1065 } 1065 }
1066 1066
1067 /* full page? */ 1067 /* full page? */
1068 if (pos_in_page == 0 && len == PAGE_CACHE_SIZE) 1068 if (pos_in_page == 0 && len == PAGE_CACHE_SIZE)
1069 return 0; 1069 return 0;
1070 1070
1071 /* past end of file? */ 1071 /* past end of file? */
1072 i_size = inode->i_size; /* caller holds i_mutex */ 1072 i_size = inode->i_size; /* caller holds i_mutex */
1073 1073
1074 if (i_size + len > inode->i_sb->s_maxbytes) { 1074 if (i_size + len > inode->i_sb->s_maxbytes) {
1075 /* file is too big */ 1075 /* file is too big */
1076 r = -EINVAL; 1076 r = -EINVAL;
1077 goto fail; 1077 goto fail;
1078 } 1078 }
1079 1079
1080 if (page_off >= i_size || 1080 if (page_off >= i_size ||
1081 (pos_in_page == 0 && (pos+len) >= i_size && 1081 (pos_in_page == 0 && (pos+len) >= i_size &&
1082 end_in_page - pos_in_page != PAGE_CACHE_SIZE)) { 1082 end_in_page - pos_in_page != PAGE_CACHE_SIZE)) {
1083 dout(" zeroing %p 0 - %d and %d - %d\n", 1083 dout(" zeroing %p 0 - %d and %d - %d\n",
1084 page, pos_in_page, end_in_page, (int)PAGE_CACHE_SIZE); 1084 page, pos_in_page, end_in_page, (int)PAGE_CACHE_SIZE);
1085 zero_user_segments(page, 1085 zero_user_segments(page,
1086 0, pos_in_page, 1086 0, pos_in_page,
1087 end_in_page, PAGE_CACHE_SIZE); 1087 end_in_page, PAGE_CACHE_SIZE);
1088 return 0; 1088 return 0;
1089 } 1089 }
1090 1090
1091 /* we need to read it. */ 1091 /* we need to read it. */
1092 up_read(&mdsc->snap_rwsem); 1092 up_read(&mdsc->snap_rwsem);
1093 r = readpage_nounlock(file, page); 1093 r = readpage_nounlock(file, page);
1094 if (r < 0) 1094 if (r < 0)
1095 goto fail_nosnap; 1095 goto fail_nosnap;
1096 goto retry_locked; 1096 goto retry_locked;
1097 1097
1098 fail: 1098 fail:
1099 up_read(&mdsc->snap_rwsem); 1099 up_read(&mdsc->snap_rwsem);
1100 fail_nosnap: 1100 fail_nosnap:
1101 unlock_page(page); 1101 unlock_page(page);
1102 return r; 1102 return r;
1103 } 1103 }
1104 1104
1105 /* 1105 /*
1106 * We are only allowed to write into/dirty the page if the page is 1106 * We are only allowed to write into/dirty the page if the page is
1107 * clean, or already dirty within the same snap context. 1107 * clean, or already dirty within the same snap context.
1108 */ 1108 */
1109 static int ceph_write_begin(struct file *file, struct address_space *mapping, 1109 static int ceph_write_begin(struct file *file, struct address_space *mapping,
1110 loff_t pos, unsigned len, unsigned flags, 1110 loff_t pos, unsigned len, unsigned flags,
1111 struct page **pagep, void **fsdata) 1111 struct page **pagep, void **fsdata)
1112 { 1112 {
1113 struct inode *inode = file_inode(file); 1113 struct inode *inode = file_inode(file);
1114 struct page *page; 1114 struct page *page;
1115 pgoff_t index = pos >> PAGE_CACHE_SHIFT; 1115 pgoff_t index = pos >> PAGE_CACHE_SHIFT;
1116 int r; 1116 int r;
1117 1117
1118 do { 1118 do {
1119 /* get a page */ 1119 /* get a page */
1120 page = grab_cache_page_write_begin(mapping, index, 0); 1120 page = grab_cache_page_write_begin(mapping, index, 0);
1121 if (!page) 1121 if (!page)
1122 return -ENOMEM; 1122 return -ENOMEM;
1123 *pagep = page; 1123 *pagep = page;
1124 1124
1125 dout("write_begin file %p inode %p page %p %d~%d\n", file, 1125 dout("write_begin file %p inode %p page %p %d~%d\n", file,
1126 inode, page, (int)pos, (int)len); 1126 inode, page, (int)pos, (int)len);
1127 1127
1128 r = ceph_update_writeable_page(file, pos, len, page); 1128 r = ceph_update_writeable_page(file, pos, len, page);
1129 } while (r == -EAGAIN); 1129 } while (r == -EAGAIN);
1130 1130
1131 return r; 1131 return r;
1132 } 1132 }
1133 1133
1134 /* 1134 /*
1135 * we don't do anything in here that simple_write_end doesn't do 1135 * we don't do anything in here that simple_write_end doesn't do
1136 * except adjust dirty page accounting and drop read lock on 1136 * except adjust dirty page accounting and drop read lock on
1137 * mdsc->snap_rwsem. 1137 * mdsc->snap_rwsem.
1138 */ 1138 */
1139 static int ceph_write_end(struct file *file, struct address_space *mapping, 1139 static int ceph_write_end(struct file *file, struct address_space *mapping,
1140 loff_t pos, unsigned len, unsigned copied, 1140 loff_t pos, unsigned len, unsigned copied,
1141 struct page *page, void *fsdata) 1141 struct page *page, void *fsdata)
1142 { 1142 {
1143 struct inode *inode = file_inode(file); 1143 struct inode *inode = file_inode(file);
1144 struct ceph_fs_client *fsc = ceph_inode_to_client(inode); 1144 struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1145 struct ceph_mds_client *mdsc = fsc->mdsc; 1145 struct ceph_mds_client *mdsc = fsc->mdsc;
1146 unsigned from = pos & (PAGE_CACHE_SIZE - 1); 1146 unsigned from = pos & (PAGE_CACHE_SIZE - 1);
1147 int check_cap = 0; 1147 int check_cap = 0;
1148 1148
1149 dout("write_end file %p inode %p page %p %d~%d (%d)\n", file, 1149 dout("write_end file %p inode %p page %p %d~%d (%d)\n", file,
1150 inode, page, (int)pos, (int)copied, (int)len); 1150 inode, page, (int)pos, (int)copied, (int)len);
1151 1151
1152 /* zero the stale part of the page if we did a short copy */ 1152 /* zero the stale part of the page if we did a short copy */
1153 if (copied < len) 1153 if (copied < len)
1154 zero_user_segment(page, from+copied, len); 1154 zero_user_segment(page, from+copied, len);
1155 1155
1156 /* did file size increase? */ 1156 /* did file size increase? */
1157 /* (no need for i_size_read(); we caller holds i_mutex */ 1157 /* (no need for i_size_read(); we caller holds i_mutex */
1158 if (pos+copied > inode->i_size) 1158 if (pos+copied > inode->i_size)
1159 check_cap = ceph_inode_set_size(inode, pos+copied); 1159 check_cap = ceph_inode_set_size(inode, pos+copied);
1160 1160
1161 if (!PageUptodate(page)) 1161 if (!PageUptodate(page))
1162 SetPageUptodate(page); 1162 SetPageUptodate(page);
1163 1163
1164 set_page_dirty(page); 1164 set_page_dirty(page);
1165 1165
1166 unlock_page(page); 1166 unlock_page(page);
1167 up_read(&mdsc->snap_rwsem); 1167 up_read(&mdsc->snap_rwsem);
1168 page_cache_release(page); 1168 page_cache_release(page);
1169 1169
1170 if (check_cap) 1170 if (check_cap)
1171 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL); 1171 ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL);
1172 1172
1173 return copied; 1173 return copied;
1174 } 1174 }
1175 1175
1176 /* 1176 /*
1177 * we set .direct_IO to indicate direct io is supported, but since we 1177 * we set .direct_IO to indicate direct io is supported, but since we
1178 * intercept O_DIRECT reads and writes early, this function should 1178 * intercept O_DIRECT reads and writes early, this function should
1179 * never get called. 1179 * never get called.
1180 */ 1180 */
1181 static ssize_t ceph_direct_io(int rw, struct kiocb *iocb, 1181 static ssize_t ceph_direct_io(int rw, struct kiocb *iocb,
1182 const struct iovec *iov, 1182 const struct iovec *iov,
1183 loff_t pos, unsigned long nr_segs) 1183 loff_t pos, unsigned long nr_segs)
1184 { 1184 {
1185 WARN_ON(1); 1185 WARN_ON(1);
1186 return -EINVAL; 1186 return -EINVAL;
1187 } 1187 }
1188 1188
1189 const struct address_space_operations ceph_aops = { 1189 const struct address_space_operations ceph_aops = {
1190 .readpage = ceph_readpage, 1190 .readpage = ceph_readpage,
1191 .readpages = ceph_readpages, 1191 .readpages = ceph_readpages,
1192 .writepage = ceph_writepage, 1192 .writepage = ceph_writepage,
1193 .writepages = ceph_writepages_start, 1193 .writepages = ceph_writepages_start,
1194 .write_begin = ceph_write_begin, 1194 .write_begin = ceph_write_begin,
1195 .write_end = ceph_write_end, 1195 .write_end = ceph_write_end,
1196 .set_page_dirty = ceph_set_page_dirty, 1196 .set_page_dirty = ceph_set_page_dirty,
1197 .invalidatepage = ceph_invalidatepage, 1197 .invalidatepage = ceph_invalidatepage,
1198 .releasepage = ceph_releasepage, 1198 .releasepage = ceph_releasepage,
1199 .direct_IO = ceph_direct_io, 1199 .direct_IO = ceph_direct_io,
1200 }; 1200 };
1201 1201
1202 1202
1203 /* 1203 /*
1204 * vm ops 1204 * vm ops
1205 */ 1205 */
1206 1206
1207 /* 1207 /*
1208 * Reuse write_begin here for simplicity. 1208 * Reuse write_begin here for simplicity.
1209 */ 1209 */
1210 static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) 1210 static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
1211 { 1211 {
1212 struct inode *inode = file_inode(vma->vm_file); 1212 struct inode *inode = file_inode(vma->vm_file);
1213 struct page *page = vmf->page; 1213 struct page *page = vmf->page;
1214 struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc; 1214 struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
1215 loff_t off = page_offset(page); 1215 loff_t off = page_offset(page);
1216 loff_t size, len; 1216 loff_t size, len;
1217 int ret; 1217 int ret;
1218 1218
1219 /* Update time before taking page lock */ 1219 /* Update time before taking page lock */
1220 file_update_time(vma->vm_file); 1220 file_update_time(vma->vm_file);
1221 1221
1222 size = i_size_read(inode); 1222 size = i_size_read(inode);
1223 if (off + PAGE_CACHE_SIZE <= size) 1223 if (off + PAGE_CACHE_SIZE <= size)
1224 len = PAGE_CACHE_SIZE; 1224 len = PAGE_CACHE_SIZE;
1225 else 1225 else
1226 len = size & ~PAGE_CACHE_MASK; 1226 len = size & ~PAGE_CACHE_MASK;
1227 1227
1228 dout("page_mkwrite %p %llu~%llu page %p idx %lu\n", inode, 1228 dout("page_mkwrite %p %llu~%llu page %p idx %lu\n", inode,
1229 off, len, page, page->index); 1229 off, len, page, page->index);
1230 1230
1231 lock_page(page); 1231 lock_page(page);
1232 1232
1233 ret = VM_FAULT_NOPAGE; 1233 ret = VM_FAULT_NOPAGE;
1234 if ((off > size) || 1234 if ((off > size) ||
1235 (page->mapping != inode->i_mapping)) 1235 (page->mapping != inode->i_mapping))
1236 goto out; 1236 goto out;
1237 1237
1238 ret = ceph_update_writeable_page(vma->vm_file, off, len, page); 1238 ret = ceph_update_writeable_page(vma->vm_file, off, len, page);
1239 if (ret == 0) { 1239 if (ret == 0) {
1240 /* success. we'll keep the page locked. */ 1240 /* success. we'll keep the page locked. */
1241 set_page_dirty(page); 1241 set_page_dirty(page);
1242 up_read(&mdsc->snap_rwsem); 1242 up_read(&mdsc->snap_rwsem);
1243 ret = VM_FAULT_LOCKED; 1243 ret = VM_FAULT_LOCKED;
1244 } else { 1244 } else {
1245 if (ret == -ENOMEM) 1245 if (ret == -ENOMEM)
1246 ret = VM_FAULT_OOM; 1246 ret = VM_FAULT_OOM;
1247 else 1247 else
1248 ret = VM_FAULT_SIGBUS; 1248 ret = VM_FAULT_SIGBUS;
1249 } 1249 }
1250 out: 1250 out:
1251 dout("page_mkwrite %p %llu~%llu = %d\n", inode, off, len, ret); 1251 dout("page_mkwrite %p %llu~%llu = %d\n", inode, off, len, ret);
1252 if (ret != VM_FAULT_LOCKED) 1252 if (ret != VM_FAULT_LOCKED)
1253 unlock_page(page); 1253 unlock_page(page);
1254 return ret; 1254 return ret;
1255 } 1255 }
1256 1256
1257 static struct vm_operations_struct ceph_vmops = { 1257 static struct vm_operations_struct ceph_vmops = {
1258 .fault = filemap_fault, 1258 .fault = filemap_fault,
1259 .page_mkwrite = ceph_page_mkwrite, 1259 .page_mkwrite = ceph_page_mkwrite,
1260 .remap_pages = generic_file_remap_pages, 1260 .remap_pages = generic_file_remap_pages,
1261 }; 1261 };
1262 1262
1263 int ceph_mmap(struct file *file, struct vm_area_struct *vma) 1263 int ceph_mmap(struct file *file, struct vm_area_struct *vma)
1264 { 1264 {
1265 struct address_space *mapping = file->f_mapping; 1265 struct address_space *mapping = file->f_mapping;
1266 1266
1267 if (!mapping->a_ops->readpage) 1267 if (!mapping->a_ops->readpage)
1268 return -ENOEXEC; 1268 return -ENOEXEC;
1269 file_accessed(file); 1269 file_accessed(file);
1270 vma->vm_ops = &ceph_vmops; 1270 vma->vm_ops = &ceph_vmops;
1271 return 0; 1271 return 0;
1272 } 1272 }
1273 1273