Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 1 | #include <linux/ceph/ceph_debug.h> |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 2 | |
| 3 | #include <linux/backing-dev.h> |
| 4 | #include <linux/fs.h> |
| 5 | #include <linux/mm.h> |
| 6 | #include <linux/pagemap.h> |
| 7 | #include <linux/writeback.h> /* generic_writepages */ |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 8 | #include <linux/slab.h> |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 9 | #include <linux/pagevec.h> |
| 10 | #include <linux/task_io_accounting_ops.h> |
| 11 | |
| 12 | #include "super.h" |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 13 | #include "mds_client.h" |
| 14 | #include <linux/ceph/osd_client.h> |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 15 | |
| 16 | /* |
| 17 | * Ceph address space ops. |
| 18 | * |
| 19 | * There are a few funny things going on here. |
| 20 | * |
| 21 | * The page->private field is used to reference a struct |
| 22 | * ceph_snap_context for _every_ dirty page. This indicates which |
| 23 | * snapshot the page was logically dirtied in, and thus which snap |
| 24 | * context needs to be associated with the osd write during writeback. |
| 25 | * |
| 26 | * Similarly, struct ceph_inode_info maintains a set of counters to |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 27 | * count dirty pages on the inode. In the absence of snapshots, |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 28 | * i_wrbuffer_ref == i_wrbuffer_ref_head == the dirty page count. |
| 29 | * |
| 30 | * When a snapshot is taken (that is, when the client receives |
| 31 | * notification that a snapshot was taken), each inode with caps and |
| 32 | * with dirty pages (dirty pages implies there is a cap) gets a new |
| 33 | * ceph_cap_snap in the i_cap_snaps list (which is sorted in ascending |
| 34 | * order, new snaps go to the tail). The i_wrbuffer_ref_head count is |
| 35 | * moved to capsnap->dirty. (Unless a sync write is currently in |
| 36 | * progress. In that case, the capsnap is said to be "pending", new |
| 37 | * writes cannot start, and the capsnap isn't "finalized" until the |
| 38 | * write completes (or fails) and a final size/mtime for the inode for |
| 39 | * that snap can be settled upon.) i_wrbuffer_ref_head is reset to 0. |
| 40 | * |
| 41 | * On writeback, we must submit writes to the osd IN SNAP ORDER. So, |
| 42 | * we look for the first capsnap in i_cap_snaps and write out pages in |
| 43 | * that snap context _only_. Then we move on to the next capsnap, |
| 44 | * eventually reaching the "live" or "head" context (i.e., pages that |
| 45 | * are not yet snapped) and are writing the most recently dirtied |
| 46 | * pages. |
| 47 | * |
| 48 | * Invalidate and so forth must take care to ensure the dirty page |
| 49 | * accounting is preserved. |
| 50 | */ |
| 51 | |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 52 | #define CONGESTION_ON_THRESH(congestion_kb) (congestion_kb >> (PAGE_SHIFT-10)) |
| 53 | #define CONGESTION_OFF_THRESH(congestion_kb) \ |
| 54 | (CONGESTION_ON_THRESH(congestion_kb) - \ |
| 55 | (CONGESTION_ON_THRESH(congestion_kb) >> 2)) |
| 56 | |
| 57 | |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 58 | |
| 59 | /* |
| 60 | * Dirty a page. Optimistically adjust accounting, on the assumption |
| 61 | * that we won't race with invalidate. If we do, readjust. |
| 62 | */ |
| 63 | static int ceph_set_page_dirty(struct page *page) |
| 64 | { |
| 65 | struct address_space *mapping = page->mapping; |
| 66 | struct inode *inode; |
| 67 | struct ceph_inode_info *ci; |
| 68 | int undo = 0; |
| 69 | struct ceph_snap_context *snapc; |
| 70 | |
| 71 | if (unlikely(!mapping)) |
| 72 | return !TestSetPageDirty(page); |
| 73 | |
| 74 | if (TestSetPageDirty(page)) { |
| 75 | dout("%p set_page_dirty %p idx %lu -- already dirty\n", |
| 76 | mapping->host, page, page->index); |
| 77 | return 0; |
| 78 | } |
| 79 | |
| 80 | inode = mapping->host; |
| 81 | ci = ceph_inode(inode); |
| 82 | |
| 83 | /* |
| 84 | * Note that we're grabbing a snapc ref here without holding |
| 85 | * any locks! |
| 86 | */ |
| 87 | snapc = ceph_get_snap_context(ci->i_snap_realm->cached_context); |
| 88 | |
| 89 | /* dirty the head */ |
Sage Weil | be65559 | 2011-11-30 09:47:09 -0800 | [diff] [blame] | 90 | spin_lock(&ci->i_ceph_lock); |
Sage Weil | 7d8cb26 | 2010-08-24 08:44:16 -0700 | [diff] [blame] | 91 | if (ci->i_head_snapc == NULL) |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 92 | ci->i_head_snapc = ceph_get_snap_context(snapc); |
| 93 | ++ci->i_wrbuffer_ref_head; |
| 94 | if (ci->i_wrbuffer_ref == 0) |
Dave Chinner | 0444d76 | 2011-03-29 18:08:50 +1100 | [diff] [blame] | 95 | ihold(inode); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 96 | ++ci->i_wrbuffer_ref; |
| 97 | dout("%p set_page_dirty %p idx %lu head %d/%d -> %d/%d " |
| 98 | "snapc %p seq %lld (%d snaps)\n", |
| 99 | mapping->host, page, page->index, |
| 100 | ci->i_wrbuffer_ref-1, ci->i_wrbuffer_ref_head-1, |
| 101 | ci->i_wrbuffer_ref, ci->i_wrbuffer_ref_head, |
| 102 | snapc, snapc->seq, snapc->num_snaps); |
Sage Weil | be65559 | 2011-11-30 09:47:09 -0800 | [diff] [blame] | 103 | spin_unlock(&ci->i_ceph_lock); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 104 | |
| 105 | /* now adjust page */ |
| 106 | spin_lock_irq(&mapping->tree_lock); |
| 107 | if (page->mapping) { /* Race with truncate? */ |
| 108 | WARN_ON_ONCE(!PageUptodate(page)); |
Michael Rubin | 679ceac | 2010-08-20 02:31:26 -0700 | [diff] [blame] | 109 | account_page_dirtied(page, page->mapping); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 110 | radix_tree_tag_set(&mapping->page_tree, |
| 111 | page_index(page), PAGECACHE_TAG_DIRTY); |
| 112 | |
| 113 | /* |
| 114 | * Reference snap context in page->private. Also set |
| 115 | * PagePrivate so that we get invalidatepage callback. |
| 116 | */ |
| 117 | page->private = (unsigned long)snapc; |
| 118 | SetPagePrivate(page); |
| 119 | } else { |
| 120 | dout("ANON set_page_dirty %p (raced truncate?)\n", page); |
| 121 | undo = 1; |
| 122 | } |
| 123 | |
| 124 | spin_unlock_irq(&mapping->tree_lock); |
| 125 | |
| 126 | if (undo) |
| 127 | /* whoops, we failed to dirty the page */ |
| 128 | ceph_put_wrbuffer_cap_refs(ci, 1, snapc); |
| 129 | |
| 130 | __mark_inode_dirty(mapping->host, I_DIRTY_PAGES); |
| 131 | |
| 132 | BUG_ON(!PageDirty(page)); |
| 133 | return 1; |
| 134 | } |
| 135 | |
| 136 | /* |
| 137 | * If we are truncating the full page (i.e. offset == 0), adjust the |
| 138 | * dirty page counters appropriately. Only called if there is private |
| 139 | * data on the page. |
| 140 | */ |
| 141 | static void ceph_invalidatepage(struct page *page, unsigned long offset) |
| 142 | { |
Alexander Beregalov | 4ce1e9a | 2010-02-22 17:17:44 +0300 | [diff] [blame] | 143 | struct inode *inode; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 144 | struct ceph_inode_info *ci; |
| 145 | struct ceph_snap_context *snapc = (void *)page->private; |
| 146 | |
| 147 | BUG_ON(!PageLocked(page)); |
| 148 | BUG_ON(!page->private); |
| 149 | BUG_ON(!PagePrivate(page)); |
| 150 | BUG_ON(!page->mapping); |
| 151 | |
Alexander Beregalov | 4ce1e9a | 2010-02-22 17:17:44 +0300 | [diff] [blame] | 152 | inode = page->mapping->host; |
| 153 | |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 154 | /* |
| 155 | * We can get non-dirty pages here due to races between |
| 156 | * set_page_dirty and truncate_complete_page; just spit out a |
| 157 | * warning, in case we end up with accounting problems later. |
| 158 | */ |
| 159 | if (!PageDirty(page)) |
| 160 | pr_err("%p invalidatepage %p page not dirty\n", inode, page); |
| 161 | |
| 162 | if (offset == 0) |
| 163 | ClearPageChecked(page); |
| 164 | |
| 165 | ci = ceph_inode(inode); |
| 166 | if (offset == 0) { |
| 167 | dout("%p invalidatepage %p idx %lu full dirty page %lu\n", |
| 168 | inode, page, page->index, offset); |
| 169 | ceph_put_wrbuffer_cap_refs(ci, 1, snapc); |
| 170 | ceph_put_snap_context(snapc); |
| 171 | page->private = 0; |
| 172 | ClearPagePrivate(page); |
| 173 | } else { |
| 174 | dout("%p invalidatepage %p idx %lu partial dirty page\n", |
| 175 | inode, page, page->index); |
| 176 | } |
| 177 | } |
| 178 | |
| 179 | /* just a sanity check */ |
| 180 | static int ceph_releasepage(struct page *page, gfp_t g) |
| 181 | { |
| 182 | struct inode *inode = page->mapping ? page->mapping->host : NULL; |
| 183 | dout("%p releasepage %p idx %lu\n", inode, page, page->index); |
| 184 | WARN_ON(PageDirty(page)); |
| 185 | WARN_ON(page->private); |
| 186 | WARN_ON(PagePrivate(page)); |
| 187 | return 0; |
| 188 | } |
| 189 | |
| 190 | /* |
| 191 | * read a single page, without unlocking it. |
| 192 | */ |
| 193 | static int readpage_nounlock(struct file *filp, struct page *page) |
| 194 | { |
| 195 | struct inode *inode = filp->f_dentry->d_inode; |
| 196 | struct ceph_inode_info *ci = ceph_inode(inode); |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 197 | struct ceph_osd_client *osdc = |
| 198 | &ceph_inode_to_client(inode)->client->osdc; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 199 | int err = 0; |
| 200 | u64 len = PAGE_CACHE_SIZE; |
| 201 | |
| 202 | dout("readpage inode %p file %p page %p index %lu\n", |
| 203 | inode, filp, page, page->index); |
| 204 | err = ceph_osdc_readpages(osdc, ceph_vino(inode), &ci->i_layout, |
| 205 | page->index << PAGE_CACHE_SHIFT, &len, |
| 206 | ci->i_truncate_seq, ci->i_truncate_size, |
Sage Weil | b7495fc | 2010-11-09 12:43:12 -0800 | [diff] [blame] | 207 | &page, 1, 0); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 208 | if (err == -ENOENT) |
| 209 | err = 0; |
| 210 | if (err < 0) { |
| 211 | SetPageError(page); |
| 212 | goto out; |
| 213 | } else if (err < PAGE_CACHE_SIZE) { |
| 214 | /* zero fill remainder of page */ |
| 215 | zero_user_segment(page, err, PAGE_CACHE_SIZE); |
| 216 | } |
| 217 | SetPageUptodate(page); |
| 218 | |
| 219 | out: |
| 220 | return err < 0 ? err : 0; |
| 221 | } |
| 222 | |
| 223 | static int ceph_readpage(struct file *filp, struct page *page) |
| 224 | { |
| 225 | int r = readpage_nounlock(filp, page); |
| 226 | unlock_page(page); |
| 227 | return r; |
| 228 | } |
| 229 | |
| 230 | /* |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 231 | * Finish an async read(ahead) op. |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 232 | */ |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 233 | static void finish_read(struct ceph_osd_request *req, struct ceph_msg *msg) |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 234 | { |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 235 | struct inode *inode = req->r_inode; |
| 236 | struct ceph_osd_reply_head *replyhead; |
| 237 | int rc, bytes; |
| 238 | int i; |
| 239 | |
| 240 | /* parse reply */ |
| 241 | replyhead = msg->front.iov_base; |
| 242 | WARN_ON(le32_to_cpu(replyhead->num_ops) == 0); |
| 243 | rc = le32_to_cpu(replyhead->result); |
| 244 | bytes = le32_to_cpu(msg->hdr.data_len); |
| 245 | |
| 246 | dout("finish_read %p req %p rc %d bytes %d\n", inode, req, rc, bytes); |
| 247 | |
| 248 | /* unlock all pages, zeroing any data we didn't read */ |
| 249 | for (i = 0; i < req->r_num_pages; i++, bytes -= PAGE_CACHE_SIZE) { |
| 250 | struct page *page = req->r_pages[i]; |
| 251 | |
| 252 | if (bytes < (int)PAGE_CACHE_SIZE) { |
| 253 | /* zero (remainder of) page */ |
| 254 | int s = bytes < 0 ? 0 : bytes; |
| 255 | zero_user_segment(page, s, PAGE_CACHE_SIZE); |
| 256 | } |
| 257 | dout("finish_read %p uptodate %p idx %lu\n", inode, page, |
| 258 | page->index); |
| 259 | flush_dcache_page(page); |
| 260 | SetPageUptodate(page); |
| 261 | unlock_page(page); |
| 262 | page_cache_release(page); |
| 263 | } |
| 264 | kfree(req->r_pages); |
| 265 | } |
| 266 | |
| 267 | /* |
| 268 | * start an async read(ahead) operation. return nr_pages we submitted |
| 269 | * a read for on success, or negative error code. |
| 270 | */ |
Sage Weil | 0d66a48 | 2011-08-04 08:21:30 -0700 | [diff] [blame] | 271 | static int start_read(struct inode *inode, struct list_head *page_list, int max) |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 272 | { |
| 273 | struct ceph_osd_client *osdc = |
| 274 | &ceph_inode_to_client(inode)->client->osdc; |
| 275 | struct ceph_inode_info *ci = ceph_inode(inode); |
| 276 | struct page *page = list_entry(page_list->prev, struct page, lru); |
| 277 | struct ceph_osd_request *req; |
| 278 | u64 off; |
| 279 | u64 len; |
| 280 | int i; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 281 | struct page **pages; |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 282 | pgoff_t next_index; |
| 283 | int nr_pages = 0; |
| 284 | int ret; |
| 285 | |
| 286 | off = page->index << PAGE_CACHE_SHIFT; |
| 287 | |
| 288 | /* count pages */ |
| 289 | next_index = page->index; |
| 290 | list_for_each_entry_reverse(page, page_list, lru) { |
| 291 | if (page->index != next_index) |
| 292 | break; |
| 293 | nr_pages++; |
| 294 | next_index++; |
Sage Weil | 0d66a48 | 2011-08-04 08:21:30 -0700 | [diff] [blame] | 295 | if (max && nr_pages == max) |
| 296 | break; |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 297 | } |
| 298 | len = nr_pages << PAGE_CACHE_SHIFT; |
| 299 | dout("start_read %p nr_pages %d is %lld~%lld\n", inode, nr_pages, |
| 300 | off, len); |
| 301 | |
| 302 | req = ceph_osdc_new_request(osdc, &ci->i_layout, ceph_vino(inode), |
| 303 | off, &len, |
| 304 | CEPH_OSD_OP_READ, CEPH_OSD_FLAG_READ, |
| 305 | NULL, 0, |
| 306 | ci->i_truncate_seq, ci->i_truncate_size, |
| 307 | NULL, false, 1, 0); |
| 308 | if (!req) |
| 309 | return -ENOMEM; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 310 | |
| 311 | /* build page vector */ |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 312 | nr_pages = len >> PAGE_CACHE_SHIFT; |
| 313 | pages = kmalloc(sizeof(*pages) * nr_pages, GFP_NOFS); |
| 314 | ret = -ENOMEM; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 315 | if (!pages) |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 316 | goto out; |
| 317 | for (i = 0; i < nr_pages; ++i) { |
| 318 | page = list_entry(page_list->prev, struct page, lru); |
| 319 | BUG_ON(PageLocked(page)); |
| 320 | list_del(&page->lru); |
| 321 | |
| 322 | dout("start_read %p adding %p idx %lu\n", inode, page, |
| 323 | page->index); |
| 324 | if (add_to_page_cache_lru(page, &inode->i_data, page->index, |
| 325 | GFP_NOFS)) { |
| 326 | page_cache_release(page); |
| 327 | dout("start_read %p add_to_page_cache failed %p\n", |
| 328 | inode, page); |
| 329 | nr_pages = i; |
| 330 | goto out_pages; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 331 | } |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 332 | pages[i] = page; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 333 | } |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 334 | req->r_pages = pages; |
| 335 | req->r_num_pages = nr_pages; |
| 336 | req->r_callback = finish_read; |
| 337 | req->r_inode = inode; |
| 338 | |
| 339 | dout("start_read %p starting %p %lld~%lld\n", inode, req, off, len); |
| 340 | ret = ceph_osdc_start_request(osdc, req, false); |
| 341 | if (ret < 0) |
| 342 | goto out_pages; |
| 343 | ceph_osdc_put_request(req); |
| 344 | return nr_pages; |
| 345 | |
| 346 | out_pages: |
| 347 | ceph_release_page_vector(pages, nr_pages); |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 348 | out: |
| 349 | ceph_osdc_put_request(req); |
| 350 | return ret; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 351 | } |
| 352 | |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 353 | |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 354 | /* |
| 355 | * Read multiple pages. Leave pages we don't read + unlock in page_list; |
| 356 | * the caller (VM) cleans them up. |
| 357 | */ |
| 358 | static int ceph_readpages(struct file *file, struct address_space *mapping, |
| 359 | struct list_head *page_list, unsigned nr_pages) |
| 360 | { |
| 361 | struct inode *inode = file->f_dentry->d_inode; |
Sage Weil | 0d66a48 | 2011-08-04 08:21:30 -0700 | [diff] [blame] | 362 | struct ceph_fs_client *fsc = ceph_inode_to_client(inode); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 363 | int rc = 0; |
Sage Weil | 0d66a48 | 2011-08-04 08:21:30 -0700 | [diff] [blame] | 364 | int max = 0; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 365 | |
Sage Weil | 0d66a48 | 2011-08-04 08:21:30 -0700 | [diff] [blame] | 366 | if (fsc->mount_options->rsize >= PAGE_CACHE_SIZE) |
| 367 | max = (fsc->mount_options->rsize + PAGE_CACHE_SIZE - 1) |
| 368 | >> PAGE_SHIFT; |
| 369 | |
| 370 | dout("readpages %p file %p nr_pages %d max %d\n", inode, file, nr_pages, |
| 371 | max); |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 372 | while (!list_empty(page_list)) { |
Sage Weil | 0d66a48 | 2011-08-04 08:21:30 -0700 | [diff] [blame] | 373 | rc = start_read(inode, page_list, max); |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 374 | if (rc < 0) |
| 375 | goto out; |
| 376 | BUG_ON(rc == 0); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 377 | } |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 378 | out: |
Sage Weil | 7c27219 | 2011-08-03 09:58:09 -0700 | [diff] [blame] | 379 | dout("readpages %p file %p ret %d\n", inode, file, rc); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 380 | return rc; |
| 381 | } |
| 382 | |
| 383 | /* |
| 384 | * Get ref for the oldest snapc for an inode with dirty data... that is, the |
| 385 | * only snap context we are allowed to write back. |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 386 | */ |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 387 | static struct ceph_snap_context *get_oldest_context(struct inode *inode, |
| 388 | u64 *snap_size) |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 389 | { |
| 390 | struct ceph_inode_info *ci = ceph_inode(inode); |
| 391 | struct ceph_snap_context *snapc = NULL; |
| 392 | struct ceph_cap_snap *capsnap = NULL; |
| 393 | |
Sage Weil | be65559 | 2011-11-30 09:47:09 -0800 | [diff] [blame] | 394 | spin_lock(&ci->i_ceph_lock); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 395 | list_for_each_entry(capsnap, &ci->i_cap_snaps, ci_item) { |
| 396 | dout(" cap_snap %p snapc %p has %d dirty pages\n", capsnap, |
| 397 | capsnap->context, capsnap->dirty_pages); |
| 398 | if (capsnap->dirty_pages) { |
| 399 | snapc = ceph_get_snap_context(capsnap->context); |
| 400 | if (snap_size) |
| 401 | *snap_size = capsnap->size; |
| 402 | break; |
| 403 | } |
| 404 | } |
Sage Weil | 7d8cb26 | 2010-08-24 08:44:16 -0700 | [diff] [blame] | 405 | if (!snapc && ci->i_wrbuffer_ref_head) { |
Sage Weil | 80e755f | 2010-03-31 21:52:10 -0700 | [diff] [blame] | 406 | snapc = ceph_get_snap_context(ci->i_head_snapc); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 407 | dout(" head snapc %p has %d dirty pages\n", |
| 408 | snapc, ci->i_wrbuffer_ref_head); |
| 409 | } |
Sage Weil | be65559 | 2011-11-30 09:47:09 -0800 | [diff] [blame] | 410 | spin_unlock(&ci->i_ceph_lock); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 411 | return snapc; |
| 412 | } |
| 413 | |
| 414 | /* |
| 415 | * Write a single page, but leave the page locked. |
| 416 | * |
| 417 | * If we get a write error, set the page error bit, but still adjust the |
| 418 | * dirty page accounting (i.e., page is no longer dirty). |
| 419 | */ |
| 420 | static int writepage_nounlock(struct page *page, struct writeback_control *wbc) |
| 421 | { |
| 422 | struct inode *inode; |
| 423 | struct ceph_inode_info *ci; |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 424 | struct ceph_fs_client *fsc; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 425 | struct ceph_osd_client *osdc; |
| 426 | loff_t page_off = page->index << PAGE_CACHE_SHIFT; |
| 427 | int len = PAGE_CACHE_SIZE; |
| 428 | loff_t i_size; |
| 429 | int err = 0; |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 430 | struct ceph_snap_context *snapc, *oldest; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 431 | u64 snap_size = 0; |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 432 | long writeback_stat; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 433 | |
| 434 | dout("writepage %p idx %lu\n", page, page->index); |
| 435 | |
| 436 | if (!page->mapping || !page->mapping->host) { |
| 437 | dout("writepage %p - no mapping\n", page); |
| 438 | return -EFAULT; |
| 439 | } |
| 440 | inode = page->mapping->host; |
| 441 | ci = ceph_inode(inode); |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 442 | fsc = ceph_inode_to_client(inode); |
| 443 | osdc = &fsc->client->osdc; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 444 | |
| 445 | /* verify this is a writeable snap context */ |
| 446 | snapc = (void *)page->private; |
| 447 | if (snapc == NULL) { |
| 448 | dout("writepage %p page %p not dirty?\n", inode, page); |
| 449 | goto out; |
| 450 | } |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 451 | oldest = get_oldest_context(inode, &snap_size); |
| 452 | if (snapc->seq > oldest->seq) { |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 453 | dout("writepage %p page %p snapc %p not writeable - noop\n", |
| 454 | inode, page, (void *)page->private); |
| 455 | /* we should only noop if called by kswapd */ |
| 456 | WARN_ON((current->flags & PF_MEMALLOC) == 0); |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 457 | ceph_put_snap_context(oldest); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 458 | goto out; |
| 459 | } |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 460 | ceph_put_snap_context(oldest); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 461 | |
| 462 | /* is this a partial page at end of file? */ |
| 463 | if (snap_size) |
| 464 | i_size = snap_size; |
| 465 | else |
| 466 | i_size = i_size_read(inode); |
| 467 | if (i_size < page_off + len) |
| 468 | len = i_size - page_off; |
| 469 | |
Sage Weil | ae00d4f | 2010-09-16 16:26:51 -0700 | [diff] [blame] | 470 | dout("writepage %p page %p index %lu on %llu~%u snapc %p\n", |
| 471 | inode, page, page->index, page_off, len, snapc); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 472 | |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 473 | writeback_stat = atomic_long_inc_return(&fsc->writeback_count); |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 474 | if (writeback_stat > |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 475 | CONGESTION_ON_THRESH(fsc->mount_options->congestion_kb)) |
| 476 | set_bdi_congested(&fsc->backing_dev_info, BLK_RW_ASYNC); |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 477 | |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 478 | set_page_writeback(page); |
| 479 | err = ceph_osdc_writepages(osdc, ceph_vino(inode), |
| 480 | &ci->i_layout, snapc, |
| 481 | page_off, len, |
| 482 | ci->i_truncate_seq, ci->i_truncate_size, |
| 483 | &inode->i_mtime, |
| 484 | &page, 1, 0, 0, true); |
| 485 | if (err < 0) { |
| 486 | dout("writepage setting page/mapping error %d %p\n", err, page); |
| 487 | SetPageError(page); |
| 488 | mapping_set_error(&inode->i_data, err); |
| 489 | if (wbc) |
| 490 | wbc->pages_skipped++; |
| 491 | } else { |
| 492 | dout("writepage cleaned page %p\n", page); |
| 493 | err = 0; /* vfs expects us to return 0 */ |
| 494 | } |
| 495 | page->private = 0; |
| 496 | ClearPagePrivate(page); |
| 497 | end_page_writeback(page); |
| 498 | ceph_put_wrbuffer_cap_refs(ci, 1, snapc); |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 499 | ceph_put_snap_context(snapc); /* page's reference */ |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 500 | out: |
| 501 | return err; |
| 502 | } |
| 503 | |
| 504 | static int ceph_writepage(struct page *page, struct writeback_control *wbc) |
| 505 | { |
Yehuda Sadeh | dbd646a | 2009-12-16 14:51:06 -0800 | [diff] [blame] | 506 | int err; |
| 507 | struct inode *inode = page->mapping->host; |
| 508 | BUG_ON(!inode); |
Sage Weil | 70b666c | 2011-05-27 09:24:26 -0700 | [diff] [blame] | 509 | ihold(inode); |
Yehuda Sadeh | dbd646a | 2009-12-16 14:51:06 -0800 | [diff] [blame] | 510 | err = writepage_nounlock(page, wbc); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 511 | unlock_page(page); |
Yehuda Sadeh | dbd646a | 2009-12-16 14:51:06 -0800 | [diff] [blame] | 512 | iput(inode); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 513 | return err; |
| 514 | } |
| 515 | |
| 516 | |
| 517 | /* |
| 518 | * lame release_pages helper. release_pages() isn't exported to |
| 519 | * modules. |
| 520 | */ |
| 521 | static void ceph_release_pages(struct page **pages, int num) |
| 522 | { |
| 523 | struct pagevec pvec; |
| 524 | int i; |
| 525 | |
| 526 | pagevec_init(&pvec, 0); |
| 527 | for (i = 0; i < num; i++) { |
| 528 | if (pagevec_add(&pvec, pages[i]) == 0) |
| 529 | pagevec_release(&pvec); |
| 530 | } |
| 531 | pagevec_release(&pvec); |
| 532 | } |
| 533 | |
| 534 | |
| 535 | /* |
| 536 | * async writeback completion handler. |
| 537 | * |
| 538 | * If we get an error, set the mapping error bit, but not the individual |
| 539 | * page error bits. |
| 540 | */ |
| 541 | static void writepages_finish(struct ceph_osd_request *req, |
| 542 | struct ceph_msg *msg) |
| 543 | { |
| 544 | struct inode *inode = req->r_inode; |
| 545 | struct ceph_osd_reply_head *replyhead; |
| 546 | struct ceph_osd_op *op; |
| 547 | struct ceph_inode_info *ci = ceph_inode(inode); |
| 548 | unsigned wrote; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 549 | struct page *page; |
| 550 | int i; |
| 551 | struct ceph_snap_context *snapc = req->r_snapc; |
| 552 | struct address_space *mapping = inode->i_mapping; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 553 | __s32 rc = -EIO; |
| 554 | u64 bytes = 0; |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 555 | struct ceph_fs_client *fsc = ceph_inode_to_client(inode); |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 556 | long writeback_stat; |
Sage Weil | 7ff899d | 2010-04-23 10:25:33 -0700 | [diff] [blame] | 557 | unsigned issued = ceph_caps_issued(ci); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 558 | |
| 559 | /* parse reply */ |
| 560 | replyhead = msg->front.iov_base; |
| 561 | WARN_ON(le32_to_cpu(replyhead->num_ops) == 0); |
| 562 | op = (void *)(replyhead + 1); |
| 563 | rc = le32_to_cpu(replyhead->result); |
| 564 | bytes = le64_to_cpu(op->extent.length); |
| 565 | |
| 566 | if (rc >= 0) { |
Sage Weil | 79788c6 | 2010-02-02 16:34:04 -0800 | [diff] [blame] | 567 | /* |
| 568 | * Assume we wrote the pages we originally sent. The |
| 569 | * osd might reply with fewer pages if our writeback |
| 570 | * raced with a truncation and was adjusted at the osd, |
| 571 | * so don't believe the reply. |
| 572 | */ |
| 573 | wrote = req->r_num_pages; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 574 | } else { |
| 575 | wrote = 0; |
| 576 | mapping_set_error(mapping, rc); |
| 577 | } |
| 578 | dout("writepages_finish %p rc %d bytes %llu wrote %d (pages)\n", |
| 579 | inode, rc, bytes, wrote); |
| 580 | |
| 581 | /* clean all pages */ |
| 582 | for (i = 0; i < req->r_num_pages; i++) { |
| 583 | page = req->r_pages[i]; |
| 584 | BUG_ON(!page); |
| 585 | WARN_ON(!PageUptodate(page)); |
| 586 | |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 587 | writeback_stat = |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 588 | atomic_long_dec_return(&fsc->writeback_count); |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 589 | if (writeback_stat < |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 590 | CONGESTION_OFF_THRESH(fsc->mount_options->congestion_kb)) |
| 591 | clear_bdi_congested(&fsc->backing_dev_info, |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 592 | BLK_RW_ASYNC); |
| 593 | |
Sage Weil | 80e755f | 2010-03-31 21:52:10 -0700 | [diff] [blame] | 594 | ceph_put_snap_context((void *)page->private); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 595 | page->private = 0; |
| 596 | ClearPagePrivate(page); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 597 | dout("unlocking %d %p\n", i, page); |
| 598 | end_page_writeback(page); |
Yehuda Sadeh | e63dc5c | 2010-02-19 00:07:01 +0000 | [diff] [blame] | 599 | |
| 600 | /* |
| 601 | * We lost the cache cap, need to truncate the page before |
| 602 | * it is unlocked, otherwise we'd truncate it later in the |
| 603 | * page truncation thread, possibly losing some data that |
| 604 | * raced its way in |
| 605 | */ |
Sage Weil | 2962507ca | 2010-05-27 10:40:43 -0700 | [diff] [blame] | 606 | if ((issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0) |
Yehuda Sadeh | e63dc5c | 2010-02-19 00:07:01 +0000 | [diff] [blame] | 607 | generic_error_remove_page(inode->i_mapping, page); |
| 608 | |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 609 | unlock_page(page); |
| 610 | } |
| 611 | dout("%p wrote+cleaned %d pages\n", inode, wrote); |
| 612 | ceph_put_wrbuffer_cap_refs(ci, req->r_num_pages, snapc); |
| 613 | |
| 614 | ceph_release_pages(req->r_pages, req->r_num_pages); |
| 615 | if (req->r_pages_from_pool) |
| 616 | mempool_free(req->r_pages, |
Cheng Renquan | 640ef79 | 2010-03-26 17:40:33 +0800 | [diff] [blame] | 617 | ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 618 | else |
| 619 | kfree(req->r_pages); |
| 620 | ceph_osdc_put_request(req); |
| 621 | } |
| 622 | |
| 623 | /* |
| 624 | * allocate a page vec, either directly, or if necessary, via a the |
| 625 | * mempool. we avoid the mempool if we can because req->r_num_pages |
| 626 | * may be less than the maximum write size. |
| 627 | */ |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 628 | static void alloc_page_vec(struct ceph_fs_client *fsc, |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 629 | struct ceph_osd_request *req) |
| 630 | { |
| 631 | req->r_pages = kmalloc(sizeof(struct page *) * req->r_num_pages, |
| 632 | GFP_NOFS); |
| 633 | if (!req->r_pages) { |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 634 | req->r_pages = mempool_alloc(fsc->wb_pagevec_pool, GFP_NOFS); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 635 | req->r_pages_from_pool = 1; |
| 636 | WARN_ON(!req->r_pages); |
| 637 | } |
| 638 | } |
| 639 | |
| 640 | /* |
| 641 | * initiate async writeback |
| 642 | */ |
| 643 | static int ceph_writepages_start(struct address_space *mapping, |
| 644 | struct writeback_control *wbc) |
| 645 | { |
| 646 | struct inode *inode = mapping->host; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 647 | struct ceph_inode_info *ci = ceph_inode(inode); |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 648 | struct ceph_fs_client *fsc; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 649 | pgoff_t index, start, end; |
| 650 | int range_whole = 0; |
| 651 | int should_loop = 1; |
| 652 | pgoff_t max_pages = 0, max_pages_ever = 0; |
Sage Weil | 80e755f | 2010-03-31 21:52:10 -0700 | [diff] [blame] | 653 | struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 654 | struct pagevec pvec; |
| 655 | int done = 0; |
| 656 | int rc = 0; |
| 657 | unsigned wsize = 1 << inode->i_blkbits; |
| 658 | struct ceph_osd_request *req = NULL; |
| 659 | int do_sync; |
| 660 | u64 snap_size = 0; |
| 661 | |
| 662 | /* |
| 663 | * Include a 'sync' in the OSD request if this is a data |
| 664 | * integrity write (e.g., O_SYNC write or fsync()), or if our |
| 665 | * cap is being revoked. |
| 666 | */ |
| 667 | do_sync = wbc->sync_mode == WB_SYNC_ALL; |
| 668 | if (ceph_caps_revoking(ci, CEPH_CAP_FILE_BUFFER)) |
| 669 | do_sync = 1; |
| 670 | dout("writepages_start %p dosync=%d (mode=%s)\n", |
| 671 | inode, do_sync, |
| 672 | wbc->sync_mode == WB_SYNC_NONE ? "NONE" : |
| 673 | (wbc->sync_mode == WB_SYNC_ALL ? "ALL" : "HOLD")); |
| 674 | |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 675 | fsc = ceph_inode_to_client(inode); |
| 676 | if (fsc->mount_state == CEPH_MOUNT_SHUTDOWN) { |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 677 | pr_warning("writepage_start %p on forced umount\n", inode); |
| 678 | return -EIO; /* we're in a forced umount, don't write! */ |
| 679 | } |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 680 | if (fsc->mount_options->wsize && fsc->mount_options->wsize < wsize) |
| 681 | wsize = fsc->mount_options->wsize; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 682 | if (wsize < PAGE_CACHE_SIZE) |
| 683 | wsize = PAGE_CACHE_SIZE; |
| 684 | max_pages_ever = wsize >> PAGE_CACHE_SHIFT; |
| 685 | |
| 686 | pagevec_init(&pvec, 0); |
| 687 | |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 688 | /* where to start/end? */ |
| 689 | if (wbc->range_cyclic) { |
| 690 | start = mapping->writeback_index; /* Start from prev offset */ |
| 691 | end = -1; |
| 692 | dout(" cyclic, start at %lu\n", start); |
| 693 | } else { |
| 694 | start = wbc->range_start >> PAGE_CACHE_SHIFT; |
| 695 | end = wbc->range_end >> PAGE_CACHE_SHIFT; |
| 696 | if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) |
| 697 | range_whole = 1; |
| 698 | should_loop = 0; |
| 699 | dout(" not cyclic, %lu to %lu\n", start, end); |
| 700 | } |
| 701 | index = start; |
| 702 | |
| 703 | retry: |
| 704 | /* find oldest snap context with dirty data */ |
| 705 | ceph_put_snap_context(snapc); |
| 706 | snapc = get_oldest_context(inode, &snap_size); |
| 707 | if (!snapc) { |
| 708 | /* hmm, why does writepages get called when there |
| 709 | is no dirty data? */ |
| 710 | dout(" no snap context with dirty data?\n"); |
| 711 | goto out; |
| 712 | } |
| 713 | dout(" oldest snapc is %p seq %lld (%d snaps)\n", |
| 714 | snapc, snapc->seq, snapc->num_snaps); |
| 715 | if (last_snapc && snapc != last_snapc) { |
| 716 | /* if we switched to a newer snapc, restart our scan at the |
| 717 | * start of the original file range. */ |
| 718 | dout(" snapc differs from last pass, restarting at %lu\n", |
| 719 | index); |
| 720 | index = start; |
| 721 | } |
| 722 | last_snapc = snapc; |
| 723 | |
| 724 | while (!done && index <= end) { |
| 725 | unsigned i; |
| 726 | int first; |
| 727 | pgoff_t next; |
| 728 | int pvec_pages, locked_pages; |
| 729 | struct page *page; |
| 730 | int want; |
| 731 | u64 offset, len; |
| 732 | struct ceph_osd_request_head *reqhead; |
| 733 | struct ceph_osd_op *op; |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 734 | long writeback_stat; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 735 | |
| 736 | next = 0; |
| 737 | locked_pages = 0; |
| 738 | max_pages = max_pages_ever; |
| 739 | |
| 740 | get_more_pages: |
| 741 | first = -1; |
| 742 | want = min(end - index, |
| 743 | min((pgoff_t)PAGEVEC_SIZE, |
| 744 | max_pages - (pgoff_t)locked_pages) - 1) |
| 745 | + 1; |
| 746 | pvec_pages = pagevec_lookup_tag(&pvec, mapping, &index, |
| 747 | PAGECACHE_TAG_DIRTY, |
| 748 | want); |
| 749 | dout("pagevec_lookup_tag got %d\n", pvec_pages); |
| 750 | if (!pvec_pages && !locked_pages) |
| 751 | break; |
| 752 | for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) { |
| 753 | page = pvec.pages[i]; |
| 754 | dout("? %p idx %lu\n", page, page->index); |
| 755 | if (locked_pages == 0) |
| 756 | lock_page(page); /* first page */ |
| 757 | else if (!trylock_page(page)) |
| 758 | break; |
| 759 | |
| 760 | /* only dirty pages, or our accounting breaks */ |
| 761 | if (unlikely(!PageDirty(page)) || |
| 762 | unlikely(page->mapping != mapping)) { |
| 763 | dout("!dirty or !mapping %p\n", page); |
| 764 | unlock_page(page); |
| 765 | break; |
| 766 | } |
| 767 | if (!wbc->range_cyclic && page->index > end) { |
| 768 | dout("end of range %p\n", page); |
| 769 | done = 1; |
| 770 | unlock_page(page); |
| 771 | break; |
| 772 | } |
| 773 | if (next && (page->index != next)) { |
| 774 | dout("not consecutive %p\n", page); |
| 775 | unlock_page(page); |
| 776 | break; |
| 777 | } |
| 778 | if (wbc->sync_mode != WB_SYNC_NONE) { |
| 779 | dout("waiting on writeback %p\n", page); |
| 780 | wait_on_page_writeback(page); |
| 781 | } |
| 782 | if ((snap_size && page_offset(page) > snap_size) || |
| 783 | (!snap_size && |
| 784 | page_offset(page) > i_size_read(inode))) { |
| 785 | dout("%p page eof %llu\n", page, snap_size ? |
| 786 | snap_size : i_size_read(inode)); |
| 787 | done = 1; |
| 788 | unlock_page(page); |
| 789 | break; |
| 790 | } |
| 791 | if (PageWriteback(page)) { |
| 792 | dout("%p under writeback\n", page); |
| 793 | unlock_page(page); |
| 794 | break; |
| 795 | } |
| 796 | |
| 797 | /* only if matching snap context */ |
Sage Weil | 80e755f | 2010-03-31 21:52:10 -0700 | [diff] [blame] | 798 | pgsnapc = (void *)page->private; |
| 799 | if (pgsnapc->seq > snapc->seq) { |
| 800 | dout("page snapc %p %lld > oldest %p %lld\n", |
| 801 | pgsnapc, pgsnapc->seq, snapc, snapc->seq); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 802 | unlock_page(page); |
| 803 | if (!locked_pages) |
| 804 | continue; /* keep looking for snap */ |
| 805 | break; |
| 806 | } |
| 807 | |
| 808 | if (!clear_page_dirty_for_io(page)) { |
| 809 | dout("%p !clear_page_dirty_for_io\n", page); |
| 810 | unlock_page(page); |
| 811 | break; |
| 812 | } |
| 813 | |
| 814 | /* ok */ |
| 815 | if (locked_pages == 0) { |
| 816 | /* prepare async write request */ |
Sage Weil | a77d9f7 | 2010-09-11 10:55:25 -0700 | [diff] [blame] | 817 | offset = (unsigned long long)page->index |
| 818 | << PAGE_CACHE_SHIFT; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 819 | len = wsize; |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 820 | req = ceph_osdc_new_request(&fsc->client->osdc, |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 821 | &ci->i_layout, |
| 822 | ceph_vino(inode), |
| 823 | offset, &len, |
| 824 | CEPH_OSD_OP_WRITE, |
| 825 | CEPH_OSD_FLAG_WRITE | |
| 826 | CEPH_OSD_FLAG_ONDISK, |
| 827 | snapc, do_sync, |
| 828 | ci->i_truncate_seq, |
| 829 | ci->i_truncate_size, |
Sage Weil | b7495fc | 2010-11-09 12:43:12 -0800 | [diff] [blame] | 830 | &inode->i_mtime, true, 1, 0); |
Henry C Chang | 8c71897 | 2011-05-03 09:45:16 +0000 | [diff] [blame] | 831 | |
| 832 | if (!req) { |
| 833 | rc = -ENOMEM; |
| 834 | unlock_page(page); |
| 835 | break; |
| 836 | } |
| 837 | |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 838 | max_pages = req->r_num_pages; |
| 839 | |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 840 | alloc_page_vec(fsc, req); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 841 | req->r_callback = writepages_finish; |
| 842 | req->r_inode = inode; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 843 | } |
| 844 | |
| 845 | /* note position of first page in pvec */ |
| 846 | if (first < 0) |
| 847 | first = i; |
| 848 | dout("%p will write page %p idx %lu\n", |
| 849 | inode, page, page->index); |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 850 | |
Sage Weil | 213c99e | 2010-08-03 10:25:11 -0700 | [diff] [blame] | 851 | writeback_stat = |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 852 | atomic_long_inc_return(&fsc->writeback_count); |
Sage Weil | 213c99e | 2010-08-03 10:25:11 -0700 | [diff] [blame] | 853 | if (writeback_stat > CONGESTION_ON_THRESH( |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 854 | fsc->mount_options->congestion_kb)) { |
| 855 | set_bdi_congested(&fsc->backing_dev_info, |
Sage Weil | 213c99e | 2010-08-03 10:25:11 -0700 | [diff] [blame] | 856 | BLK_RW_ASYNC); |
Yehuda Sadeh | 2baba25 | 2009-12-18 13:51:57 -0800 | [diff] [blame] | 857 | } |
| 858 | |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 859 | set_page_writeback(page); |
| 860 | req->r_pages[locked_pages] = page; |
| 861 | locked_pages++; |
| 862 | next = page->index + 1; |
| 863 | } |
| 864 | |
| 865 | /* did we get anything? */ |
| 866 | if (!locked_pages) |
| 867 | goto release_pvec_pages; |
| 868 | if (i) { |
| 869 | int j; |
| 870 | BUG_ON(!locked_pages || first < 0); |
| 871 | |
| 872 | if (pvec_pages && i == pvec_pages && |
| 873 | locked_pages < max_pages) { |
| 874 | dout("reached end pvec, trying for more\n"); |
| 875 | pagevec_reinit(&pvec); |
| 876 | goto get_more_pages; |
| 877 | } |
| 878 | |
| 879 | /* shift unused pages over in the pvec... we |
| 880 | * will need to release them below. */ |
| 881 | for (j = i; j < pvec_pages; j++) { |
| 882 | dout(" pvec leftover page %p\n", |
| 883 | pvec.pages[j]); |
| 884 | pvec.pages[j-i+first] = pvec.pages[j]; |
| 885 | } |
| 886 | pvec.nr -= i-first; |
| 887 | } |
| 888 | |
| 889 | /* submit the write */ |
| 890 | offset = req->r_pages[0]->index << PAGE_CACHE_SHIFT; |
| 891 | len = min((snap_size ? snap_size : i_size_read(inode)) - offset, |
| 892 | (u64)locked_pages << PAGE_CACHE_SHIFT); |
| 893 | dout("writepages got %d pages at %llu~%llu\n", |
| 894 | locked_pages, offset, len); |
| 895 | |
| 896 | /* revise final length, page count */ |
| 897 | req->r_num_pages = locked_pages; |
| 898 | reqhead = req->r_request->front.iov_base; |
| 899 | op = (void *)(reqhead + 1); |
| 900 | op->extent.length = cpu_to_le64(len); |
| 901 | op->payload_len = cpu_to_le32(len); |
| 902 | req->r_request->hdr.data_len = cpu_to_le32(len); |
| 903 | |
Sage Weil | 9d6fcb0 | 2011-05-12 15:48:16 -0700 | [diff] [blame] | 904 | rc = ceph_osdc_start_request(&fsc->client->osdc, req, true); |
| 905 | BUG_ON(rc); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 906 | req = NULL; |
| 907 | |
| 908 | /* continue? */ |
| 909 | index = next; |
| 910 | wbc->nr_to_write -= locked_pages; |
| 911 | if (wbc->nr_to_write <= 0) |
| 912 | done = 1; |
| 913 | |
| 914 | release_pvec_pages: |
| 915 | dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr, |
| 916 | pvec.nr ? pvec.pages[0] : NULL); |
| 917 | pagevec_release(&pvec); |
| 918 | |
| 919 | if (locked_pages && !done) |
| 920 | goto retry; |
| 921 | } |
| 922 | |
| 923 | if (should_loop && !done) { |
| 924 | /* more to do; loop back to beginning of file */ |
| 925 | dout("writepages looping back to beginning of file\n"); |
| 926 | should_loop = 0; |
| 927 | index = 0; |
| 928 | goto retry; |
| 929 | } |
| 930 | |
| 931 | if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0)) |
| 932 | mapping->writeback_index = index; |
| 933 | |
| 934 | out: |
| 935 | if (req) |
| 936 | ceph_osdc_put_request(req); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 937 | ceph_put_snap_context(snapc); |
| 938 | dout("writepages done, rc = %d\n", rc); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 939 | return rc; |
| 940 | } |
| 941 | |
| 942 | |
| 943 | |
| 944 | /* |
| 945 | * See if a given @snapc is either writeable, or already written. |
| 946 | */ |
| 947 | static int context_is_writeable_or_written(struct inode *inode, |
| 948 | struct ceph_snap_context *snapc) |
| 949 | { |
| 950 | struct ceph_snap_context *oldest = get_oldest_context(inode, NULL); |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 951 | int ret = !oldest || snapc->seq <= oldest->seq; |
| 952 | |
| 953 | ceph_put_snap_context(oldest); |
| 954 | return ret; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 955 | } |
| 956 | |
| 957 | /* |
| 958 | * We are only allowed to write into/dirty the page if the page is |
| 959 | * clean, or already dirty within the same snap context. |
Sage Weil | 8f883c2 | 2010-03-19 13:27:53 -0700 | [diff] [blame] | 960 | * |
| 961 | * called with page locked. |
| 962 | * return success with page locked, |
| 963 | * or any failure (incl -EAGAIN) with page unlocked. |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 964 | */ |
Yehuda Sadeh | 4af6b22 | 2010-02-09 11:02:51 -0800 | [diff] [blame] | 965 | static int ceph_update_writeable_page(struct file *file, |
| 966 | loff_t pos, unsigned len, |
| 967 | struct page *page) |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 968 | { |
| 969 | struct inode *inode = file->f_dentry->d_inode; |
| 970 | struct ceph_inode_info *ci = ceph_inode(inode); |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 971 | struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 972 | loff_t page_off = pos & PAGE_CACHE_MASK; |
| 973 | int pos_in_page = pos & ~PAGE_CACHE_MASK; |
| 974 | int end_in_page = pos_in_page + len; |
| 975 | loff_t i_size; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 976 | int r; |
Sage Weil | 80e755f | 2010-03-31 21:52:10 -0700 | [diff] [blame] | 977 | struct ceph_snap_context *snapc, *oldest; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 978 | |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 979 | retry_locked: |
| 980 | /* writepages currently holds page lock, but if we change that later, */ |
| 981 | wait_on_page_writeback(page); |
| 982 | |
| 983 | /* check snap context */ |
| 984 | BUG_ON(!ci->i_snap_realm); |
| 985 | down_read(&mdsc->snap_rwsem); |
| 986 | BUG_ON(!ci->i_snap_realm->cached_context); |
Sage Weil | 80e755f | 2010-03-31 21:52:10 -0700 | [diff] [blame] | 987 | snapc = (void *)page->private; |
| 988 | if (snapc && snapc != ci->i_head_snapc) { |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 989 | /* |
| 990 | * this page is already dirty in another (older) snap |
| 991 | * context! is it writeable now? |
| 992 | */ |
Sage Weil | 80e755f | 2010-03-31 21:52:10 -0700 | [diff] [blame] | 993 | oldest = get_oldest_context(inode, NULL); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 994 | up_read(&mdsc->snap_rwsem); |
| 995 | |
Sage Weil | 80e755f | 2010-03-31 21:52:10 -0700 | [diff] [blame] | 996 | if (snapc->seq > oldest->seq) { |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 997 | ceph_put_snap_context(oldest); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 998 | dout(" page %p snapc %p not current or oldest\n", |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 999 | page, snapc); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1000 | /* |
| 1001 | * queue for writeback, and wait for snapc to |
| 1002 | * be writeable or written |
| 1003 | */ |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 1004 | snapc = ceph_get_snap_context(snapc); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1005 | unlock_page(page); |
Sage Weil | 3c6f6b7 | 2010-02-09 15:24:44 -0800 | [diff] [blame] | 1006 | ceph_queue_writeback(inode); |
Sage Weil | 8f883c2 | 2010-03-19 13:27:53 -0700 | [diff] [blame] | 1007 | r = wait_event_interruptible(ci->i_cap_wq, |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1008 | context_is_writeable_or_written(inode, snapc)); |
| 1009 | ceph_put_snap_context(snapc); |
Sage Weil | 8f883c2 | 2010-03-19 13:27:53 -0700 | [diff] [blame] | 1010 | if (r == -ERESTARTSYS) |
| 1011 | return r; |
Yehuda Sadeh | 4af6b22 | 2010-02-09 11:02:51 -0800 | [diff] [blame] | 1012 | return -EAGAIN; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1013 | } |
Sage Weil | 6298a33 | 2010-03-31 22:01:38 -0700 | [diff] [blame] | 1014 | ceph_put_snap_context(oldest); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1015 | |
| 1016 | /* yay, writeable, do it now (without dropping page lock) */ |
| 1017 | dout(" page %p snapc %p not current, but oldest\n", |
| 1018 | page, snapc); |
| 1019 | if (!clear_page_dirty_for_io(page)) |
| 1020 | goto retry_locked; |
| 1021 | r = writepage_nounlock(page, NULL); |
| 1022 | if (r < 0) |
| 1023 | goto fail_nosnap; |
| 1024 | goto retry_locked; |
| 1025 | } |
| 1026 | |
| 1027 | if (PageUptodate(page)) { |
| 1028 | dout(" page %p already uptodate\n", page); |
| 1029 | return 0; |
| 1030 | } |
| 1031 | |
| 1032 | /* full page? */ |
| 1033 | if (pos_in_page == 0 && len == PAGE_CACHE_SIZE) |
| 1034 | return 0; |
| 1035 | |
| 1036 | /* past end of file? */ |
| 1037 | i_size = inode->i_size; /* caller holds i_mutex */ |
| 1038 | |
| 1039 | if (i_size + len > inode->i_sb->s_maxbytes) { |
| 1040 | /* file is too big */ |
| 1041 | r = -EINVAL; |
| 1042 | goto fail; |
| 1043 | } |
| 1044 | |
| 1045 | if (page_off >= i_size || |
| 1046 | (pos_in_page == 0 && (pos+len) >= i_size && |
| 1047 | end_in_page - pos_in_page != PAGE_CACHE_SIZE)) { |
| 1048 | dout(" zeroing %p 0 - %d and %d - %d\n", |
| 1049 | page, pos_in_page, end_in_page, (int)PAGE_CACHE_SIZE); |
| 1050 | zero_user_segments(page, |
| 1051 | 0, pos_in_page, |
| 1052 | end_in_page, PAGE_CACHE_SIZE); |
| 1053 | return 0; |
| 1054 | } |
| 1055 | |
| 1056 | /* we need to read it. */ |
| 1057 | up_read(&mdsc->snap_rwsem); |
| 1058 | r = readpage_nounlock(file, page); |
| 1059 | if (r < 0) |
| 1060 | goto fail_nosnap; |
| 1061 | goto retry_locked; |
| 1062 | |
| 1063 | fail: |
| 1064 | up_read(&mdsc->snap_rwsem); |
| 1065 | fail_nosnap: |
| 1066 | unlock_page(page); |
| 1067 | return r; |
| 1068 | } |
| 1069 | |
| 1070 | /* |
Yehuda Sadeh | 4af6b22 | 2010-02-09 11:02:51 -0800 | [diff] [blame] | 1071 | * We are only allowed to write into/dirty the page if the page is |
| 1072 | * clean, or already dirty within the same snap context. |
| 1073 | */ |
| 1074 | static int ceph_write_begin(struct file *file, struct address_space *mapping, |
| 1075 | loff_t pos, unsigned len, unsigned flags, |
| 1076 | struct page **pagep, void **fsdata) |
| 1077 | { |
| 1078 | struct inode *inode = file->f_dentry->d_inode; |
| 1079 | struct page *page; |
| 1080 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
| 1081 | int r; |
| 1082 | |
| 1083 | do { |
Sage Weil | 8f883c2 | 2010-03-19 13:27:53 -0700 | [diff] [blame] | 1084 | /* get a page */ |
Yehuda Sadeh | 4af6b22 | 2010-02-09 11:02:51 -0800 | [diff] [blame] | 1085 | page = grab_cache_page_write_begin(mapping, index, 0); |
| 1086 | if (!page) |
| 1087 | return -ENOMEM; |
| 1088 | *pagep = page; |
| 1089 | |
| 1090 | dout("write_begin file %p inode %p page %p %d~%d\n", file, |
Sage Weil | 213c99e | 2010-08-03 10:25:11 -0700 | [diff] [blame] | 1091 | inode, page, (int)pos, (int)len); |
Yehuda Sadeh | 4af6b22 | 2010-02-09 11:02:51 -0800 | [diff] [blame] | 1092 | |
| 1093 | r = ceph_update_writeable_page(file, pos, len, page); |
| 1094 | } while (r == -EAGAIN); |
| 1095 | |
| 1096 | return r; |
| 1097 | } |
| 1098 | |
| 1099 | /* |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1100 | * we don't do anything in here that simple_write_end doesn't do |
| 1101 | * except adjust dirty page accounting and drop read lock on |
| 1102 | * mdsc->snap_rwsem. |
| 1103 | */ |
| 1104 | static int ceph_write_end(struct file *file, struct address_space *mapping, |
| 1105 | loff_t pos, unsigned len, unsigned copied, |
| 1106 | struct page *page, void *fsdata) |
| 1107 | { |
| 1108 | struct inode *inode = file->f_dentry->d_inode; |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 1109 | struct ceph_fs_client *fsc = ceph_inode_to_client(inode); |
| 1110 | struct ceph_mds_client *mdsc = fsc->mdsc; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1111 | unsigned from = pos & (PAGE_CACHE_SIZE - 1); |
| 1112 | int check_cap = 0; |
| 1113 | |
| 1114 | dout("write_end file %p inode %p page %p %d~%d (%d)\n", file, |
| 1115 | inode, page, (int)pos, (int)copied, (int)len); |
| 1116 | |
| 1117 | /* zero the stale part of the page if we did a short copy */ |
| 1118 | if (copied < len) |
| 1119 | zero_user_segment(page, from+copied, len); |
| 1120 | |
| 1121 | /* did file size increase? */ |
| 1122 | /* (no need for i_size_read(); we caller holds i_mutex */ |
| 1123 | if (pos+copied > inode->i_size) |
| 1124 | check_cap = ceph_inode_set_size(inode, pos+copied); |
| 1125 | |
| 1126 | if (!PageUptodate(page)) |
| 1127 | SetPageUptodate(page); |
| 1128 | |
| 1129 | set_page_dirty(page); |
| 1130 | |
| 1131 | unlock_page(page); |
| 1132 | up_read(&mdsc->snap_rwsem); |
| 1133 | page_cache_release(page); |
| 1134 | |
| 1135 | if (check_cap) |
| 1136 | ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL); |
| 1137 | |
| 1138 | return copied; |
| 1139 | } |
| 1140 | |
| 1141 | /* |
| 1142 | * we set .direct_IO to indicate direct io is supported, but since we |
| 1143 | * intercept O_DIRECT reads and writes early, this function should |
| 1144 | * never get called. |
| 1145 | */ |
| 1146 | static ssize_t ceph_direct_io(int rw, struct kiocb *iocb, |
| 1147 | const struct iovec *iov, |
| 1148 | loff_t pos, unsigned long nr_segs) |
| 1149 | { |
| 1150 | WARN_ON(1); |
| 1151 | return -EINVAL; |
| 1152 | } |
| 1153 | |
| 1154 | const struct address_space_operations ceph_aops = { |
| 1155 | .readpage = ceph_readpage, |
| 1156 | .readpages = ceph_readpages, |
| 1157 | .writepage = ceph_writepage, |
| 1158 | .writepages = ceph_writepages_start, |
| 1159 | .write_begin = ceph_write_begin, |
| 1160 | .write_end = ceph_write_end, |
| 1161 | .set_page_dirty = ceph_set_page_dirty, |
| 1162 | .invalidatepage = ceph_invalidatepage, |
| 1163 | .releasepage = ceph_releasepage, |
| 1164 | .direct_IO = ceph_direct_io, |
| 1165 | }; |
| 1166 | |
| 1167 | |
| 1168 | /* |
| 1169 | * vm ops |
| 1170 | */ |
| 1171 | |
| 1172 | /* |
| 1173 | * Reuse write_begin here for simplicity. |
| 1174 | */ |
| 1175 | static int ceph_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
| 1176 | { |
| 1177 | struct inode *inode = vma->vm_file->f_dentry->d_inode; |
| 1178 | struct page *page = vmf->page; |
Yehuda Sadeh | 3d14c5d | 2010-04-06 15:14:15 -0700 | [diff] [blame] | 1179 | struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1180 | loff_t off = page->index << PAGE_CACHE_SHIFT; |
| 1181 | loff_t size, len; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1182 | int ret; |
| 1183 | |
| 1184 | size = i_size_read(inode); |
| 1185 | if (off + PAGE_CACHE_SIZE <= size) |
| 1186 | len = PAGE_CACHE_SIZE; |
| 1187 | else |
| 1188 | len = size & ~PAGE_CACHE_MASK; |
| 1189 | |
| 1190 | dout("page_mkwrite %p %llu~%llu page %p idx %lu\n", inode, |
| 1191 | off, len, page, page->index); |
Yehuda Sadeh | 4af6b22 | 2010-02-09 11:02:51 -0800 | [diff] [blame] | 1192 | |
| 1193 | lock_page(page); |
| 1194 | |
| 1195 | ret = VM_FAULT_NOPAGE; |
| 1196 | if ((off > size) || |
| 1197 | (page->mapping != inode->i_mapping)) |
| 1198 | goto out; |
| 1199 | |
| 1200 | ret = ceph_update_writeable_page(vma->vm_file, off, len, page); |
| 1201 | if (ret == 0) { |
| 1202 | /* success. we'll keep the page locked. */ |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1203 | set_page_dirty(page); |
| 1204 | up_read(&mdsc->snap_rwsem); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1205 | ret = VM_FAULT_LOCKED; |
| 1206 | } else { |
Yehuda Sadeh | 4af6b22 | 2010-02-09 11:02:51 -0800 | [diff] [blame] | 1207 | if (ret == -ENOMEM) |
| 1208 | ret = VM_FAULT_OOM; |
| 1209 | else |
| 1210 | ret = VM_FAULT_SIGBUS; |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1211 | } |
Yehuda Sadeh | 4af6b22 | 2010-02-09 11:02:51 -0800 | [diff] [blame] | 1212 | out: |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1213 | dout("page_mkwrite %p %llu~%llu = %d\n", inode, off, len, ret); |
Yehuda Sadeh | 4af6b22 | 2010-02-09 11:02:51 -0800 | [diff] [blame] | 1214 | if (ret != VM_FAULT_LOCKED) |
| 1215 | unlock_page(page); |
Sage Weil | 1d3576f | 2009-10-06 11:31:09 -0700 | [diff] [blame] | 1216 | return ret; |
| 1217 | } |
| 1218 | |
| 1219 | static struct vm_operations_struct ceph_vmops = { |
| 1220 | .fault = filemap_fault, |
| 1221 | .page_mkwrite = ceph_page_mkwrite, |
| 1222 | }; |
| 1223 | |
| 1224 | int ceph_mmap(struct file *file, struct vm_area_struct *vma) |
| 1225 | { |
| 1226 | struct address_space *mapping = file->f_mapping; |
| 1227 | |
| 1228 | if (!mapping->a_ops->readpage) |
| 1229 | return -ENOEXEC; |
| 1230 | file_accessed(file); |
| 1231 | vma->vm_ops = &ceph_vmops; |
| 1232 | vma->vm_flags |= VM_CAN_NONLINEAR; |
| 1233 | return 0; |
| 1234 | } |