12874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later 231143d5dSDavid Howells /* handling of writes to regular files and writing back to the server 331143d5dSDavid Howells * 431143d5dSDavid Howells * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. 531143d5dSDavid Howells * Written by David Howells (dhowells@redhat.com) 631143d5dSDavid Howells */ 74343d008SDavid Howells 84af3c9ccSAlexey Dobriyan #include <linux/backing-dev.h> 931143d5dSDavid Howells #include <linux/slab.h> 1031143d5dSDavid Howells #include <linux/fs.h> 1131143d5dSDavid Howells #include <linux/pagemap.h> 1231143d5dSDavid Howells #include <linux/writeback.h> 1331143d5dSDavid Howells #include <linux/pagevec.h> 1431143d5dSDavid Howells #include "internal.h" 1531143d5dSDavid Howells 1631143d5dSDavid Howells /* 1731143d5dSDavid Howells * mark a page as having been made dirty and thus needing writeback 1831143d5dSDavid Howells */ 1931143d5dSDavid Howells int afs_set_page_dirty(struct page *page) 2031143d5dSDavid Howells { 2131143d5dSDavid Howells _enter(""); 2231143d5dSDavid Howells return __set_page_dirty_nobuffers(page); 2331143d5dSDavid Howells } 2431143d5dSDavid Howells 2531143d5dSDavid Howells /* 2631143d5dSDavid Howells * partly or wholly fill a page that's under preparation for writing 2731143d5dSDavid Howells */ 2831143d5dSDavid Howells static int afs_fill_page(struct afs_vnode *vnode, struct key *key, 29e8e581a8SDavid Howells loff_t pos, unsigned int len, struct page *page) 3031143d5dSDavid Howells { 31196ee9cdSDavid Howells struct afs_read *req; 322a0b4f64SDavid Howells size_t p; 332a0b4f64SDavid Howells void *data; 3431143d5dSDavid Howells int ret; 3531143d5dSDavid Howells 365e7f2337SAnton Blanchard _enter(",,%llu", (unsigned long long)pos); 3731143d5dSDavid Howells 382a0b4f64SDavid Howells if (pos >= vnode->vfs_inode.i_size) { 392a0b4f64SDavid Howells p = pos & ~PAGE_MASK; 402a0b4f64SDavid Howells ASSERTCMP(p + len, <=, PAGE_SIZE); 412a0b4f64SDavid Howells data = kmap(page); 422a0b4f64SDavid Howells memset(data + p, 0, len); 432a0b4f64SDavid Howells kunmap(page); 442a0b4f64SDavid Howells return 0; 452a0b4f64SDavid Howells } 462a0b4f64SDavid Howells 47ee102584SZhengyuan Liu req = kzalloc(struct_size(req, array, 1), GFP_KERNEL); 48196ee9cdSDavid Howells if (!req) 49196ee9cdSDavid Howells return -ENOMEM; 50196ee9cdSDavid Howells 51f3ddee8dSDavid Howells refcount_set(&req->usage, 1); 52196ee9cdSDavid Howells req->pos = pos; 53e8e581a8SDavid Howells req->len = len; 54196ee9cdSDavid Howells req->nr_pages = 1; 55f3ddee8dSDavid Howells req->pages = req->array; 56196ee9cdSDavid Howells req->pages[0] = page; 575611ef28SDavid Howells get_page(page); 58196ee9cdSDavid Howells 59d2ddc776SDavid Howells ret = afs_fetch_data(vnode, key, req); 60196ee9cdSDavid Howells afs_put_read(req); 6131143d5dSDavid Howells if (ret < 0) { 6231143d5dSDavid Howells if (ret == -ENOENT) { 6331143d5dSDavid Howells _debug("got NOENT from server" 6431143d5dSDavid Howells " - marking file deleted and stale"); 6531143d5dSDavid Howells set_bit(AFS_VNODE_DELETED, &vnode->flags); 6631143d5dSDavid Howells ret = -ESTALE; 6731143d5dSDavid Howells } 6831143d5dSDavid Howells } 6931143d5dSDavid Howells 7031143d5dSDavid Howells _leave(" = %d", ret); 7131143d5dSDavid Howells return ret; 7231143d5dSDavid Howells } 7331143d5dSDavid Howells 7431143d5dSDavid Howells /* 7531143d5dSDavid Howells * prepare to perform part of a write to a page 7631143d5dSDavid Howells */ 7715b4650eSNick Piggin int afs_write_begin(struct file *file, struct address_space *mapping, 7815b4650eSNick Piggin loff_t pos, unsigned len, unsigned flags, 7921db2cdcSDavid Howells struct page **_page, void **fsdata) 8031143d5dSDavid Howells { 81496ad9aaSAl Viro struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); 8215b4650eSNick Piggin struct page *page; 83215804a9SDavid Howells struct key *key = afs_file_key(file); 844343d008SDavid Howells unsigned long priv; 854343d008SDavid Howells unsigned f, from = pos & (PAGE_SIZE - 1); 864343d008SDavid Howells unsigned t, to = from + len; 8709cbfeafSKirill A. Shutemov pgoff_t index = pos >> PAGE_SHIFT; 8831143d5dSDavid Howells int ret; 8931143d5dSDavid Howells 903b6492dfSDavid Howells _enter("{%llx:%llu},{%lx},%u,%u", 9115b4650eSNick Piggin vnode->fid.vid, vnode->fid.vnode, index, from, to); 9231143d5dSDavid Howells 9354566b2cSNick Piggin page = grab_cache_page_write_begin(mapping, index, flags); 944343d008SDavid Howells if (!page) 9515b4650eSNick Piggin return -ENOMEM; 9615b4650eSNick Piggin 9709cbfeafSKirill A. Shutemov if (!PageUptodate(page) && len != PAGE_SIZE) { 98e8e581a8SDavid Howells ret = afs_fill_page(vnode, key, pos & PAGE_MASK, PAGE_SIZE, page); 9931143d5dSDavid Howells if (ret < 0) { 1006d06b0d2SDavid Howells unlock_page(page); 1016d06b0d2SDavid Howells put_page(page); 10231143d5dSDavid Howells _leave(" = %d [prep]", ret); 10331143d5dSDavid Howells return ret; 10431143d5dSDavid Howells } 10515b4650eSNick Piggin SetPageUptodate(page); 10631143d5dSDavid Howells } 10731143d5dSDavid Howells 10831143d5dSDavid Howells try_again: 1094343d008SDavid Howells /* See if this page is already partially written in a way that we can 1104343d008SDavid Howells * merge the new write with. 1114343d008SDavid Howells */ 1124343d008SDavid Howells t = f = 0; 1134343d008SDavid Howells if (PagePrivate(page)) { 1144343d008SDavid Howells priv = page_private(page); 115185f0c70SDavid Howells f = afs_page_dirty_from(priv); 116185f0c70SDavid Howells t = afs_page_dirty_to(priv); 1174343d008SDavid Howells ASSERTCMP(f, <=, t); 11831143d5dSDavid Howells } 11931143d5dSDavid Howells 1204343d008SDavid Howells if (f != t) { 1215a039c32SDavid Howells if (PageWriteback(page)) { 1225a039c32SDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("alrdy"), 1235a039c32SDavid Howells page->index, priv); 1245a039c32SDavid Howells goto flush_conflicting_write; 1255a039c32SDavid Howells } 1265a813276SDavid Howells /* If the file is being filled locally, allow inter-write 1275a813276SDavid Howells * spaces to be merged into writes. If it's not, only write 1285a813276SDavid Howells * back what the user gives us. 1295a813276SDavid Howells */ 1305a813276SDavid Howells if (!test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags) && 1315a813276SDavid Howells (to < f || from > t)) 1324343d008SDavid Howells goto flush_conflicting_write; 13331143d5dSDavid Howells } 13431143d5dSDavid Howells 13521db2cdcSDavid Howells *_page = page; 1364343d008SDavid Howells _leave(" = 0"); 13731143d5dSDavid Howells return 0; 13831143d5dSDavid Howells 1394343d008SDavid Howells /* The previous write and this write aren't adjacent or overlapping, so 1404343d008SDavid Howells * flush the page out. 1414343d008SDavid Howells */ 1424343d008SDavid Howells flush_conflicting_write: 14331143d5dSDavid Howells _debug("flush conflict"); 1444343d008SDavid Howells ret = write_one_page(page); 14521db2cdcSDavid Howells if (ret < 0) 14621db2cdcSDavid Howells goto error; 14731143d5dSDavid Howells 1484343d008SDavid Howells ret = lock_page_killable(page); 14921db2cdcSDavid Howells if (ret < 0) 15021db2cdcSDavid Howells goto error; 15121db2cdcSDavid Howells goto try_again; 15221db2cdcSDavid Howells 15321db2cdcSDavid Howells error: 15421db2cdcSDavid Howells put_page(page); 1554343d008SDavid Howells _leave(" = %d", ret); 1564343d008SDavid Howells return ret; 1574343d008SDavid Howells } 15831143d5dSDavid Howells 15931143d5dSDavid Howells /* 16031143d5dSDavid Howells * finalise part of a write to a page 16131143d5dSDavid Howells */ 16215b4650eSNick Piggin int afs_write_end(struct file *file, struct address_space *mapping, 16315b4650eSNick Piggin loff_t pos, unsigned len, unsigned copied, 16415b4650eSNick Piggin struct page *page, void *fsdata) 16531143d5dSDavid Howells { 166496ad9aaSAl Viro struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); 167215804a9SDavid Howells struct key *key = afs_file_key(file); 168f792e3acSDavid Howells unsigned long priv; 169f792e3acSDavid Howells unsigned int f, from = pos & (PAGE_SIZE - 1); 170f792e3acSDavid Howells unsigned int t, to = from + copied; 17131143d5dSDavid Howells loff_t i_size, maybe_i_size; 1723ad216eeSDavid Howells int ret = 0; 17331143d5dSDavid Howells 1743b6492dfSDavid Howells _enter("{%llx:%llu},{%lx}", 17515b4650eSNick Piggin vnode->fid.vid, vnode->fid.vnode, page->index); 17631143d5dSDavid Howells 1773ad216eeSDavid Howells if (copied == 0) 1783ad216eeSDavid Howells goto out; 1793ad216eeSDavid Howells 18015b4650eSNick Piggin maybe_i_size = pos + copied; 18131143d5dSDavid Howells 18231143d5dSDavid Howells i_size = i_size_read(&vnode->vfs_inode); 18331143d5dSDavid Howells if (maybe_i_size > i_size) { 1841f32ef79SDavid Howells write_seqlock(&vnode->cb_lock); 18531143d5dSDavid Howells i_size = i_size_read(&vnode->vfs_inode); 18631143d5dSDavid Howells if (maybe_i_size > i_size) 18731143d5dSDavid Howells i_size_write(&vnode->vfs_inode, maybe_i_size); 1881f32ef79SDavid Howells write_sequnlock(&vnode->cb_lock); 18931143d5dSDavid Howells } 19031143d5dSDavid Howells 191e8e581a8SDavid Howells if (!PageUptodate(page)) { 192e8e581a8SDavid Howells if (copied < len) { 193e8e581a8SDavid Howells /* Try and load any missing data from the server. The 194e8e581a8SDavid Howells * unmarshalling routine will take care of clearing any 195e8e581a8SDavid Howells * bits that are beyond the EOF. 196e8e581a8SDavid Howells */ 197e8e581a8SDavid Howells ret = afs_fill_page(vnode, key, pos + copied, 198e8e581a8SDavid Howells len - copied, page); 199e8e581a8SDavid Howells if (ret < 0) 200afae457dSDavid Howells goto out; 201e8e581a8SDavid Howells } 202e8e581a8SDavid Howells SetPageUptodate(page); 203e8e581a8SDavid Howells } 204e8e581a8SDavid Howells 205f792e3acSDavid Howells if (PagePrivate(page)) { 206f792e3acSDavid Howells priv = page_private(page); 207185f0c70SDavid Howells f = afs_page_dirty_from(priv); 208185f0c70SDavid Howells t = afs_page_dirty_to(priv); 209f792e3acSDavid Howells if (from < f) 210f792e3acSDavid Howells f = from; 211f792e3acSDavid Howells if (to > t) 212f792e3acSDavid Howells t = to; 213185f0c70SDavid Howells priv = afs_page_dirty(f, t); 214f792e3acSDavid Howells set_page_private(page, priv); 215f792e3acSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("dirty+"), 216f792e3acSDavid Howells page->index, priv); 217f792e3acSDavid Howells } else { 218185f0c70SDavid Howells priv = afs_page_dirty(from, to); 219f792e3acSDavid Howells attach_page_private(page, (void *)priv); 220f792e3acSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("dirty"), 221f792e3acSDavid Howells page->index, priv); 222f792e3acSDavid Howells } 223f792e3acSDavid Howells 22431143d5dSDavid Howells set_page_dirty(page); 22531143d5dSDavid Howells if (PageDirty(page)) 22631143d5dSDavid Howells _debug("dirtied"); 227afae457dSDavid Howells ret = copied; 228afae457dSDavid Howells 229afae457dSDavid Howells out: 23015b4650eSNick Piggin unlock_page(page); 23109cbfeafSKirill A. Shutemov put_page(page); 232afae457dSDavid Howells return ret; 23331143d5dSDavid Howells } 23431143d5dSDavid Howells 23531143d5dSDavid Howells /* 23631143d5dSDavid Howells * kill all the pages in the given range 23731143d5dSDavid Howells */ 2384343d008SDavid Howells static void afs_kill_pages(struct address_space *mapping, 23931143d5dSDavid Howells pgoff_t first, pgoff_t last) 24031143d5dSDavid Howells { 2414343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 24231143d5dSDavid Howells struct pagevec pv; 24331143d5dSDavid Howells unsigned count, loop; 24431143d5dSDavid Howells 2453b6492dfSDavid Howells _enter("{%llx:%llu},%lx-%lx", 24631143d5dSDavid Howells vnode->fid.vid, vnode->fid.vnode, first, last); 24731143d5dSDavid Howells 24886679820SMel Gorman pagevec_init(&pv); 24931143d5dSDavid Howells 25031143d5dSDavid Howells do { 25131143d5dSDavid Howells _debug("kill %lx-%lx", first, last); 25231143d5dSDavid Howells 25331143d5dSDavid Howells count = last - first + 1; 25431143d5dSDavid Howells if (count > PAGEVEC_SIZE) 25531143d5dSDavid Howells count = PAGEVEC_SIZE; 2564343d008SDavid Howells pv.nr = find_get_pages_contig(mapping, first, count, pv.pages); 25731143d5dSDavid Howells ASSERTCMP(pv.nr, ==, count); 25831143d5dSDavid Howells 25931143d5dSDavid Howells for (loop = 0; loop < count; loop++) { 2607286a35eSDavid Howells struct page *page = pv.pages[loop]; 2617286a35eSDavid Howells ClearPageUptodate(page); 2627286a35eSDavid Howells SetPageError(page); 2634343d008SDavid Howells end_page_writeback(page); 2644343d008SDavid Howells if (page->index >= first) 2654343d008SDavid Howells first = page->index + 1; 2664343d008SDavid Howells lock_page(page); 2674343d008SDavid Howells generic_error_remove_page(mapping, page); 26821bd68f1SMarc Dionne unlock_page(page); 2694343d008SDavid Howells } 2704343d008SDavid Howells 2714343d008SDavid Howells __pagevec_release(&pv); 2724343d008SDavid Howells } while (first <= last); 2734343d008SDavid Howells 2744343d008SDavid Howells _leave(""); 2754343d008SDavid Howells } 2764343d008SDavid Howells 2774343d008SDavid Howells /* 2784343d008SDavid Howells * Redirty all the pages in a given range. 2794343d008SDavid Howells */ 2804343d008SDavid Howells static void afs_redirty_pages(struct writeback_control *wbc, 2814343d008SDavid Howells struct address_space *mapping, 2824343d008SDavid Howells pgoff_t first, pgoff_t last) 2834343d008SDavid Howells { 2844343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 2854343d008SDavid Howells struct pagevec pv; 2864343d008SDavid Howells unsigned count, loop; 2874343d008SDavid Howells 2883b6492dfSDavid Howells _enter("{%llx:%llu},%lx-%lx", 2894343d008SDavid Howells vnode->fid.vid, vnode->fid.vnode, first, last); 2904343d008SDavid Howells 291487e2c9fSLinus Torvalds pagevec_init(&pv); 2924343d008SDavid Howells 2934343d008SDavid Howells do { 2944343d008SDavid Howells _debug("redirty %lx-%lx", first, last); 2954343d008SDavid Howells 2964343d008SDavid Howells count = last - first + 1; 2974343d008SDavid Howells if (count > PAGEVEC_SIZE) 2984343d008SDavid Howells count = PAGEVEC_SIZE; 2994343d008SDavid Howells pv.nr = find_get_pages_contig(mapping, first, count, pv.pages); 3004343d008SDavid Howells ASSERTCMP(pv.nr, ==, count); 3014343d008SDavid Howells 3024343d008SDavid Howells for (loop = 0; loop < count; loop++) { 3034343d008SDavid Howells struct page *page = pv.pages[loop]; 3044343d008SDavid Howells 3054343d008SDavid Howells redirty_page_for_writepage(wbc, page); 3067286a35eSDavid Howells end_page_writeback(page); 3077286a35eSDavid Howells if (page->index >= first) 3087286a35eSDavid Howells first = page->index + 1; 30931143d5dSDavid Howells } 31031143d5dSDavid Howells 31131143d5dSDavid Howells __pagevec_release(&pv); 3124343d008SDavid Howells } while (first <= last); 31331143d5dSDavid Howells 31431143d5dSDavid Howells _leave(""); 31531143d5dSDavid Howells } 31631143d5dSDavid Howells 31731143d5dSDavid Howells /* 318a58823acSDavid Howells * completion of write to server 319a58823acSDavid Howells */ 320a58823acSDavid Howells static void afs_pages_written_back(struct afs_vnode *vnode, 321a58823acSDavid Howells pgoff_t first, pgoff_t last) 322a58823acSDavid Howells { 323a58823acSDavid Howells struct pagevec pv; 324a58823acSDavid Howells unsigned long priv; 325a58823acSDavid Howells unsigned count, loop; 326a58823acSDavid Howells 327a58823acSDavid Howells _enter("{%llx:%llu},{%lx-%lx}", 328a58823acSDavid Howells vnode->fid.vid, vnode->fid.vnode, first, last); 329a58823acSDavid Howells 330a58823acSDavid Howells pagevec_init(&pv); 331a58823acSDavid Howells 332a58823acSDavid Howells do { 333a58823acSDavid Howells _debug("done %lx-%lx", first, last); 334a58823acSDavid Howells 335a58823acSDavid Howells count = last - first + 1; 336a58823acSDavid Howells if (count > PAGEVEC_SIZE) 337a58823acSDavid Howells count = PAGEVEC_SIZE; 338a58823acSDavid Howells pv.nr = find_get_pages_contig(vnode->vfs_inode.i_mapping, 339a58823acSDavid Howells first, count, pv.pages); 340a58823acSDavid Howells ASSERTCMP(pv.nr, ==, count); 341a58823acSDavid Howells 342a58823acSDavid Howells for (loop = 0; loop < count; loop++) { 343fa04a40bSDavid Howells priv = (unsigned long)detach_page_private(pv.pages[loop]); 344a58823acSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("clear"), 345a58823acSDavid Howells pv.pages[loop]->index, priv); 346a58823acSDavid Howells end_page_writeback(pv.pages[loop]); 347a58823acSDavid Howells } 348a58823acSDavid Howells first += count; 349a58823acSDavid Howells __pagevec_release(&pv); 350a58823acSDavid Howells } while (first <= last); 351a58823acSDavid Howells 352a58823acSDavid Howells afs_prune_wb_keys(vnode); 353a58823acSDavid Howells _leave(""); 354a58823acSDavid Howells } 355a58823acSDavid Howells 356a58823acSDavid Howells /* 357e49c7b2fSDavid Howells * Find a key to use for the writeback. We cached the keys used to author the 358e49c7b2fSDavid Howells * writes on the vnode. *_wbk will contain the last writeback key used or NULL 359e49c7b2fSDavid Howells * and we need to start from there if it's set. 360e49c7b2fSDavid Howells */ 361e49c7b2fSDavid Howells static int afs_get_writeback_key(struct afs_vnode *vnode, 362e49c7b2fSDavid Howells struct afs_wb_key **_wbk) 363e49c7b2fSDavid Howells { 364e49c7b2fSDavid Howells struct afs_wb_key *wbk = NULL; 365e49c7b2fSDavid Howells struct list_head *p; 366e49c7b2fSDavid Howells int ret = -ENOKEY, ret2; 367e49c7b2fSDavid Howells 368e49c7b2fSDavid Howells spin_lock(&vnode->wb_lock); 369e49c7b2fSDavid Howells if (*_wbk) 370e49c7b2fSDavid Howells p = (*_wbk)->vnode_link.next; 371e49c7b2fSDavid Howells else 372e49c7b2fSDavid Howells p = vnode->wb_keys.next; 373e49c7b2fSDavid Howells 374e49c7b2fSDavid Howells while (p != &vnode->wb_keys) { 375e49c7b2fSDavid Howells wbk = list_entry(p, struct afs_wb_key, vnode_link); 376e49c7b2fSDavid Howells _debug("wbk %u", key_serial(wbk->key)); 377e49c7b2fSDavid Howells ret2 = key_validate(wbk->key); 378e49c7b2fSDavid Howells if (ret2 == 0) { 379e49c7b2fSDavid Howells refcount_inc(&wbk->usage); 380e49c7b2fSDavid Howells _debug("USE WB KEY %u", key_serial(wbk->key)); 381e49c7b2fSDavid Howells break; 382e49c7b2fSDavid Howells } 383e49c7b2fSDavid Howells 384e49c7b2fSDavid Howells wbk = NULL; 385e49c7b2fSDavid Howells if (ret == -ENOKEY) 386e49c7b2fSDavid Howells ret = ret2; 387e49c7b2fSDavid Howells p = p->next; 388e49c7b2fSDavid Howells } 389e49c7b2fSDavid Howells 390e49c7b2fSDavid Howells spin_unlock(&vnode->wb_lock); 391e49c7b2fSDavid Howells if (*_wbk) 392e49c7b2fSDavid Howells afs_put_wb_key(*_wbk); 393e49c7b2fSDavid Howells *_wbk = wbk; 394e49c7b2fSDavid Howells return 0; 395e49c7b2fSDavid Howells } 396e49c7b2fSDavid Howells 397e49c7b2fSDavid Howells static void afs_store_data_success(struct afs_operation *op) 398e49c7b2fSDavid Howells { 399e49c7b2fSDavid Howells struct afs_vnode *vnode = op->file[0].vnode; 400e49c7b2fSDavid Howells 401da8d0755SDavid Howells op->ctime = op->file[0].scb.status.mtime_client; 402e49c7b2fSDavid Howells afs_vnode_commit_status(op, &op->file[0]); 403e49c7b2fSDavid Howells if (op->error == 0) { 404d383e346SDavid Howells if (!op->store.laundering) 405e49c7b2fSDavid Howells afs_pages_written_back(vnode, op->store.first, op->store.last); 406e49c7b2fSDavid Howells afs_stat_v(vnode, n_stores); 407e49c7b2fSDavid Howells atomic_long_add((op->store.last * PAGE_SIZE + op->store.last_to) - 408e49c7b2fSDavid Howells (op->store.first * PAGE_SIZE + op->store.first_offset), 409e49c7b2fSDavid Howells &afs_v2net(vnode)->n_store_bytes); 410e49c7b2fSDavid Howells } 411e49c7b2fSDavid Howells } 412e49c7b2fSDavid Howells 413e49c7b2fSDavid Howells static const struct afs_operation_ops afs_store_data_operation = { 414e49c7b2fSDavid Howells .issue_afs_rpc = afs_fs_store_data, 415e49c7b2fSDavid Howells .issue_yfs_rpc = yfs_fs_store_data, 416e49c7b2fSDavid Howells .success = afs_store_data_success, 417e49c7b2fSDavid Howells }; 418e49c7b2fSDavid Howells 419e49c7b2fSDavid Howells /* 420d2ddc776SDavid Howells * write to a file 42131143d5dSDavid Howells */ 4224343d008SDavid Howells static int afs_store_data(struct address_space *mapping, 4234343d008SDavid Howells pgoff_t first, pgoff_t last, 424d383e346SDavid Howells unsigned offset, unsigned to, bool laundering) 42531143d5dSDavid Howells { 4264343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 427e49c7b2fSDavid Howells struct afs_operation *op; 4284343d008SDavid Howells struct afs_wb_key *wbk = NULL; 429e49c7b2fSDavid Howells int ret; 430d2ddc776SDavid Howells 4313b6492dfSDavid Howells _enter("%s{%llx:%llu.%u},%lx,%lx,%x,%x", 432d2ddc776SDavid Howells vnode->volume->name, 433d2ddc776SDavid Howells vnode->fid.vid, 434d2ddc776SDavid Howells vnode->fid.vnode, 435d2ddc776SDavid Howells vnode->fid.unique, 436d2ddc776SDavid Howells first, last, offset, to); 437d2ddc776SDavid Howells 438e49c7b2fSDavid Howells ret = afs_get_writeback_key(vnode, &wbk); 439e49c7b2fSDavid Howells if (ret) { 4404343d008SDavid Howells _leave(" = %d [no keys]", ret); 4414343d008SDavid Howells return ret; 442d2ddc776SDavid Howells } 443d2ddc776SDavid Howells 444e49c7b2fSDavid Howells op = afs_alloc_operation(wbk->key, vnode->volume); 445e49c7b2fSDavid Howells if (IS_ERR(op)) { 446e49c7b2fSDavid Howells afs_put_wb_key(wbk); 447e49c7b2fSDavid Howells return -ENOMEM; 448d2ddc776SDavid Howells } 449d2ddc776SDavid Howells 450e49c7b2fSDavid Howells afs_op_set_vnode(op, 0, vnode); 451e49c7b2fSDavid Howells op->file[0].dv_delta = 1; 452e49c7b2fSDavid Howells op->store.mapping = mapping; 453e49c7b2fSDavid Howells op->store.first = first; 454e49c7b2fSDavid Howells op->store.last = last; 455e49c7b2fSDavid Howells op->store.first_offset = offset; 456e49c7b2fSDavid Howells op->store.last_to = to; 457d383e346SDavid Howells op->store.laundering = laundering; 458b3597945SDavid Howells op->mtime = vnode->vfs_inode.i_mtime; 459811f04baSDavid Howells op->flags |= AFS_OPERATION_UNINTR; 460e49c7b2fSDavid Howells op->ops = &afs_store_data_operation; 461e49c7b2fSDavid Howells 462e49c7b2fSDavid Howells try_next_key: 463e49c7b2fSDavid Howells afs_begin_vnode_operation(op); 464e49c7b2fSDavid Howells afs_wait_for_operation(op); 465e49c7b2fSDavid Howells 466e49c7b2fSDavid Howells switch (op->error) { 4674343d008SDavid Howells case -EACCES: 4684343d008SDavid Howells case -EPERM: 4694343d008SDavid Howells case -ENOKEY: 4704343d008SDavid Howells case -EKEYEXPIRED: 4714343d008SDavid Howells case -EKEYREJECTED: 4724343d008SDavid Howells case -EKEYREVOKED: 4734343d008SDavid Howells _debug("next"); 474e49c7b2fSDavid Howells 475e49c7b2fSDavid Howells ret = afs_get_writeback_key(vnode, &wbk); 476e49c7b2fSDavid Howells if (ret == 0) { 477e49c7b2fSDavid Howells key_put(op->key); 478e49c7b2fSDavid Howells op->key = key_get(wbk->key); 4794343d008SDavid Howells goto try_next_key; 4804343d008SDavid Howells } 481e49c7b2fSDavid Howells break; 482e49c7b2fSDavid Howells } 4834343d008SDavid Howells 4844343d008SDavid Howells afs_put_wb_key(wbk); 485e49c7b2fSDavid Howells _leave(" = %d", op->error); 486e49c7b2fSDavid Howells return afs_put_operation(op); 487d2ddc776SDavid Howells } 488d2ddc776SDavid Howells 489d2ddc776SDavid Howells /* 4904343d008SDavid Howells * Synchronously write back the locked page and any subsequent non-locked dirty 4914343d008SDavid Howells * pages. 49231143d5dSDavid Howells */ 4934343d008SDavid Howells static int afs_write_back_from_locked_page(struct address_space *mapping, 4944343d008SDavid Howells struct writeback_control *wbc, 4954343d008SDavid Howells struct page *primary_page, 4964343d008SDavid Howells pgoff_t final_page) 49731143d5dSDavid Howells { 49813524ab3SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 49931143d5dSDavid Howells struct page *pages[8], *page; 5004343d008SDavid Howells unsigned long count, priv; 5014343d008SDavid Howells unsigned n, offset, to, f, t; 50231143d5dSDavid Howells pgoff_t start, first, last; 503793fe82eSDavid Howells loff_t i_size, end; 50431143d5dSDavid Howells int loop, ret; 50531143d5dSDavid Howells 50631143d5dSDavid Howells _enter(",%lx", primary_page->index); 50731143d5dSDavid Howells 50831143d5dSDavid Howells count = 1; 50931143d5dSDavid Howells if (test_set_page_writeback(primary_page)) 51031143d5dSDavid Howells BUG(); 51131143d5dSDavid Howells 5124343d008SDavid Howells /* Find all consecutive lockable dirty pages that have contiguous 5134343d008SDavid Howells * written regions, stopping when we find a page that is not 5144343d008SDavid Howells * immediately lockable, is not dirty or is missing, or we reach the 5154343d008SDavid Howells * end of the range. 5164343d008SDavid Howells */ 51731143d5dSDavid Howells start = primary_page->index; 5184343d008SDavid Howells priv = page_private(primary_page); 519185f0c70SDavid Howells offset = afs_page_dirty_from(priv); 520185f0c70SDavid Howells to = afs_page_dirty_to(priv); 52113524ab3SDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("store"), 52213524ab3SDavid Howells primary_page->index, priv); 5234343d008SDavid Howells 5244343d008SDavid Howells WARN_ON(offset == to); 52513524ab3SDavid Howells if (offset == to) 52613524ab3SDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("WARN"), 52713524ab3SDavid Howells primary_page->index, priv); 5284343d008SDavid Howells 5295a813276SDavid Howells if (start >= final_page || 5305a813276SDavid Howells (to < PAGE_SIZE && !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags))) 53131143d5dSDavid Howells goto no_more; 5324343d008SDavid Howells 53331143d5dSDavid Howells start++; 53431143d5dSDavid Howells do { 53531143d5dSDavid Howells _debug("more %lx [%lx]", start, count); 5364343d008SDavid Howells n = final_page - start + 1; 53731143d5dSDavid Howells if (n > ARRAY_SIZE(pages)) 53831143d5dSDavid Howells n = ARRAY_SIZE(pages); 5394343d008SDavid Howells n = find_get_pages_contig(mapping, start, ARRAY_SIZE(pages), pages); 54031143d5dSDavid Howells _debug("fgpc %u", n); 54131143d5dSDavid Howells if (n == 0) 54231143d5dSDavid Howells goto no_more; 54331143d5dSDavid Howells if (pages[0]->index != start) { 5449d577b6aSDavid Howells do { 5459d577b6aSDavid Howells put_page(pages[--n]); 5469d577b6aSDavid Howells } while (n > 0); 54731143d5dSDavid Howells goto no_more; 54831143d5dSDavid Howells } 54931143d5dSDavid Howells 55031143d5dSDavid Howells for (loop = 0; loop < n; loop++) { 55131143d5dSDavid Howells page = pages[loop]; 5525a813276SDavid Howells if (to != PAGE_SIZE && 5535a813276SDavid Howells !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)) 5545a813276SDavid Howells break; 5554343d008SDavid Howells if (page->index > final_page) 55631143d5dSDavid Howells break; 557529ae9aaSNick Piggin if (!trylock_page(page)) 55831143d5dSDavid Howells break; 5594343d008SDavid Howells if (!PageDirty(page) || PageWriteback(page)) { 56031143d5dSDavid Howells unlock_page(page); 56131143d5dSDavid Howells break; 56231143d5dSDavid Howells } 5634343d008SDavid Howells 5644343d008SDavid Howells priv = page_private(page); 565185f0c70SDavid Howells f = afs_page_dirty_from(priv); 566185f0c70SDavid Howells t = afs_page_dirty_to(priv); 5675a813276SDavid Howells if (f != 0 && 5685a813276SDavid Howells !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)) { 5694343d008SDavid Howells unlock_page(page); 5704343d008SDavid Howells break; 5714343d008SDavid Howells } 5724343d008SDavid Howells to = t; 5734343d008SDavid Howells 57413524ab3SDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("store+"), 57513524ab3SDavid Howells page->index, priv); 57613524ab3SDavid Howells 57731143d5dSDavid Howells if (!clear_page_dirty_for_io(page)) 57831143d5dSDavid Howells BUG(); 57931143d5dSDavid Howells if (test_set_page_writeback(page)) 58031143d5dSDavid Howells BUG(); 58131143d5dSDavid Howells unlock_page(page); 58231143d5dSDavid Howells put_page(page); 58331143d5dSDavid Howells } 58431143d5dSDavid Howells count += loop; 58531143d5dSDavid Howells if (loop < n) { 58631143d5dSDavid Howells for (; loop < n; loop++) 58731143d5dSDavid Howells put_page(pages[loop]); 58831143d5dSDavid Howells goto no_more; 58931143d5dSDavid Howells } 59031143d5dSDavid Howells 59131143d5dSDavid Howells start += loop; 5924343d008SDavid Howells } while (start <= final_page && count < 65536); 59331143d5dSDavid Howells 59431143d5dSDavid Howells no_more: 5954343d008SDavid Howells /* We now have a contiguous set of dirty pages, each with writeback 5964343d008SDavid Howells * set; the first page is still locked at this point, but all the rest 5974343d008SDavid Howells * have been unlocked. 5984343d008SDavid Howells */ 5994343d008SDavid Howells unlock_page(primary_page); 6004343d008SDavid Howells 60131143d5dSDavid Howells first = primary_page->index; 60231143d5dSDavid Howells last = first + count - 1; 60331143d5dSDavid Howells 604793fe82eSDavid Howells end = (loff_t)last * PAGE_SIZE + to; 605793fe82eSDavid Howells i_size = i_size_read(&vnode->vfs_inode); 606793fe82eSDavid Howells 60731143d5dSDavid Howells _debug("write back %lx[%u..] to %lx[..%u]", first, offset, last, to); 608793fe82eSDavid Howells if (end > i_size) 609793fe82eSDavid Howells to = i_size & ~PAGE_MASK; 61031143d5dSDavid Howells 611d383e346SDavid Howells ret = afs_store_data(mapping, first, last, offset, to, false); 61231143d5dSDavid Howells switch (ret) { 6134343d008SDavid Howells case 0: 6144343d008SDavid Howells ret = count; 6154343d008SDavid Howells break; 6164343d008SDavid Howells 6174343d008SDavid Howells default: 6184343d008SDavid Howells pr_notice("kAFS: Unexpected error from FS.StoreData %d\n", ret); 619df561f66SGustavo A. R. Silva fallthrough; 6204343d008SDavid Howells case -EACCES: 6214343d008SDavid Howells case -EPERM: 6224343d008SDavid Howells case -ENOKEY: 6234343d008SDavid Howells case -EKEYEXPIRED: 6244343d008SDavid Howells case -EKEYREJECTED: 6254343d008SDavid Howells case -EKEYREVOKED: 6264343d008SDavid Howells afs_redirty_pages(wbc, mapping, first, last); 6274343d008SDavid Howells mapping_set_error(mapping, ret); 6284343d008SDavid Howells break; 6294343d008SDavid Howells 63031143d5dSDavid Howells case -EDQUOT: 63131143d5dSDavid Howells case -ENOSPC: 6324343d008SDavid Howells afs_redirty_pages(wbc, mapping, first, last); 6334343d008SDavid Howells mapping_set_error(mapping, -ENOSPC); 63431143d5dSDavid Howells break; 6354343d008SDavid Howells 63631143d5dSDavid Howells case -EROFS: 63731143d5dSDavid Howells case -EIO: 63831143d5dSDavid Howells case -EREMOTEIO: 63931143d5dSDavid Howells case -EFBIG: 64031143d5dSDavid Howells case -ENOENT: 64131143d5dSDavid Howells case -ENOMEDIUM: 64231143d5dSDavid Howells case -ENXIO: 643f51375cdSDavid Howells trace_afs_file_error(vnode, ret, afs_file_error_writeback_fail); 6444343d008SDavid Howells afs_kill_pages(mapping, first, last); 6454343d008SDavid Howells mapping_set_error(mapping, ret); 64631143d5dSDavid Howells break; 64731143d5dSDavid Howells } 64831143d5dSDavid Howells 64931143d5dSDavid Howells _leave(" = %d", ret); 65031143d5dSDavid Howells return ret; 65131143d5dSDavid Howells } 65231143d5dSDavid Howells 65331143d5dSDavid Howells /* 65431143d5dSDavid Howells * write a page back to the server 65531143d5dSDavid Howells * - the caller locked the page for us 65631143d5dSDavid Howells */ 65731143d5dSDavid Howells int afs_writepage(struct page *page, struct writeback_control *wbc) 65831143d5dSDavid Howells { 65931143d5dSDavid Howells int ret; 66031143d5dSDavid Howells 66131143d5dSDavid Howells _enter("{%lx},", page->index); 66231143d5dSDavid Howells 6634343d008SDavid Howells ret = afs_write_back_from_locked_page(page->mapping, wbc, page, 6644343d008SDavid Howells wbc->range_end >> PAGE_SHIFT); 66531143d5dSDavid Howells if (ret < 0) { 66631143d5dSDavid Howells _leave(" = %d", ret); 66731143d5dSDavid Howells return 0; 66831143d5dSDavid Howells } 66931143d5dSDavid Howells 67031143d5dSDavid Howells wbc->nr_to_write -= ret; 67131143d5dSDavid Howells 67231143d5dSDavid Howells _leave(" = 0"); 67331143d5dSDavid Howells return 0; 67431143d5dSDavid Howells } 67531143d5dSDavid Howells 67631143d5dSDavid Howells /* 67731143d5dSDavid Howells * write a region of pages back to the server 67831143d5dSDavid Howells */ 679c1206a2cSAdrian Bunk static int afs_writepages_region(struct address_space *mapping, 68031143d5dSDavid Howells struct writeback_control *wbc, 68131143d5dSDavid Howells pgoff_t index, pgoff_t end, pgoff_t *_next) 68231143d5dSDavid Howells { 68331143d5dSDavid Howells struct page *page; 68431143d5dSDavid Howells int ret, n; 68531143d5dSDavid Howells 68631143d5dSDavid Howells _enter(",,%lx,%lx,", index, end); 68731143d5dSDavid Howells 68831143d5dSDavid Howells do { 689aef6e415SJan Kara n = find_get_pages_range_tag(mapping, &index, end, 690aef6e415SJan Kara PAGECACHE_TAG_DIRTY, 1, &page); 69131143d5dSDavid Howells if (!n) 69231143d5dSDavid Howells break; 69331143d5dSDavid Howells 69431143d5dSDavid Howells _debug("wback %lx", page->index); 69531143d5dSDavid Howells 696b93b0163SMatthew Wilcox /* 697b93b0163SMatthew Wilcox * at this point we hold neither the i_pages lock nor the 698b93b0163SMatthew Wilcox * page lock: the page may be truncated or invalidated 699b93b0163SMatthew Wilcox * (changing page->mapping to NULL), or even swizzled 700b93b0163SMatthew Wilcox * back from swapper_space to tmpfs file mapping 70131143d5dSDavid Howells */ 7024343d008SDavid Howells ret = lock_page_killable(page); 7034343d008SDavid Howells if (ret < 0) { 7044343d008SDavid Howells put_page(page); 7054343d008SDavid Howells _leave(" = %d", ret); 7064343d008SDavid Howells return ret; 7074343d008SDavid Howells } 70831143d5dSDavid Howells 709c5051c7bSDavid Howells if (page->mapping != mapping || !PageDirty(page)) { 71031143d5dSDavid Howells unlock_page(page); 71109cbfeafSKirill A. Shutemov put_page(page); 71231143d5dSDavid Howells continue; 71331143d5dSDavid Howells } 71431143d5dSDavid Howells 715c5051c7bSDavid Howells if (PageWriteback(page)) { 716c5051c7bSDavid Howells unlock_page(page); 71731143d5dSDavid Howells if (wbc->sync_mode != WB_SYNC_NONE) 71831143d5dSDavid Howells wait_on_page_writeback(page); 71929c8bbbdSDavid Howells put_page(page); 72031143d5dSDavid Howells continue; 72131143d5dSDavid Howells } 72231143d5dSDavid Howells 72365a15109SDavid Howells if (!clear_page_dirty_for_io(page)) 72465a15109SDavid Howells BUG(); 7254343d008SDavid Howells ret = afs_write_back_from_locked_page(mapping, wbc, page, end); 72609cbfeafSKirill A. Shutemov put_page(page); 72731143d5dSDavid Howells if (ret < 0) { 72831143d5dSDavid Howells _leave(" = %d", ret); 72931143d5dSDavid Howells return ret; 73031143d5dSDavid Howells } 73131143d5dSDavid Howells 73231143d5dSDavid Howells wbc->nr_to_write -= ret; 73331143d5dSDavid Howells 73431143d5dSDavid Howells cond_resched(); 73531143d5dSDavid Howells } while (index < end && wbc->nr_to_write > 0); 73631143d5dSDavid Howells 73731143d5dSDavid Howells *_next = index; 73831143d5dSDavid Howells _leave(" = 0 [%lx]", *_next); 73931143d5dSDavid Howells return 0; 74031143d5dSDavid Howells } 74131143d5dSDavid Howells 74231143d5dSDavid Howells /* 74331143d5dSDavid Howells * write some of the pending data back to the server 74431143d5dSDavid Howells */ 74531143d5dSDavid Howells int afs_writepages(struct address_space *mapping, 74631143d5dSDavid Howells struct writeback_control *wbc) 74731143d5dSDavid Howells { 748ec0fa0b6SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 74931143d5dSDavid Howells pgoff_t start, end, next; 75031143d5dSDavid Howells int ret; 75131143d5dSDavid Howells 75231143d5dSDavid Howells _enter(""); 75331143d5dSDavid Howells 754ec0fa0b6SDavid Howells /* We have to be careful as we can end up racing with setattr() 755ec0fa0b6SDavid Howells * truncating the pagecache since the caller doesn't take a lock here 756ec0fa0b6SDavid Howells * to prevent it. 757ec0fa0b6SDavid Howells */ 758ec0fa0b6SDavid Howells if (wbc->sync_mode == WB_SYNC_ALL) 759ec0fa0b6SDavid Howells down_read(&vnode->validate_lock); 760ec0fa0b6SDavid Howells else if (!down_read_trylock(&vnode->validate_lock)) 761ec0fa0b6SDavid Howells return 0; 762ec0fa0b6SDavid Howells 76331143d5dSDavid Howells if (wbc->range_cyclic) { 76431143d5dSDavid Howells start = mapping->writeback_index; 76531143d5dSDavid Howells end = -1; 76631143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, start, end, &next); 7671b430beeSWu Fengguang if (start > 0 && wbc->nr_to_write > 0 && ret == 0) 76831143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, 0, start, 76931143d5dSDavid Howells &next); 77031143d5dSDavid Howells mapping->writeback_index = next; 77131143d5dSDavid Howells } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) { 77209cbfeafSKirill A. Shutemov end = (pgoff_t)(LLONG_MAX >> PAGE_SHIFT); 77331143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, 0, end, &next); 77431143d5dSDavid Howells if (wbc->nr_to_write > 0) 77531143d5dSDavid Howells mapping->writeback_index = next; 77631143d5dSDavid Howells } else { 77709cbfeafSKirill A. Shutemov start = wbc->range_start >> PAGE_SHIFT; 77809cbfeafSKirill A. Shutemov end = wbc->range_end >> PAGE_SHIFT; 77931143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, start, end, &next); 78031143d5dSDavid Howells } 78131143d5dSDavid Howells 782ec0fa0b6SDavid Howells up_read(&vnode->validate_lock); 78331143d5dSDavid Howells _leave(" = %d", ret); 78431143d5dSDavid Howells return ret; 78531143d5dSDavid Howells } 78631143d5dSDavid Howells 78731143d5dSDavid Howells /* 78831143d5dSDavid Howells * write to an AFS file 78931143d5dSDavid Howells */ 79050b5551dSAl Viro ssize_t afs_file_write(struct kiocb *iocb, struct iov_iter *from) 79131143d5dSDavid Howells { 792496ad9aaSAl Viro struct afs_vnode *vnode = AFS_FS_I(file_inode(iocb->ki_filp)); 79331143d5dSDavid Howells ssize_t result; 79450b5551dSAl Viro size_t count = iov_iter_count(from); 79531143d5dSDavid Howells 7963b6492dfSDavid Howells _enter("{%llx:%llu},{%zu},", 79750b5551dSAl Viro vnode->fid.vid, vnode->fid.vnode, count); 79831143d5dSDavid Howells 79931143d5dSDavid Howells if (IS_SWAPFILE(&vnode->vfs_inode)) { 80031143d5dSDavid Howells printk(KERN_INFO 80131143d5dSDavid Howells "AFS: Attempt to write to active swap file!\n"); 80231143d5dSDavid Howells return -EBUSY; 80331143d5dSDavid Howells } 80431143d5dSDavid Howells 80531143d5dSDavid Howells if (!count) 80631143d5dSDavid Howells return 0; 80731143d5dSDavid Howells 80850b5551dSAl Viro result = generic_file_write_iter(iocb, from); 80931143d5dSDavid Howells 81031143d5dSDavid Howells _leave(" = %zd", result); 81131143d5dSDavid Howells return result; 81231143d5dSDavid Howells } 81331143d5dSDavid Howells 81431143d5dSDavid Howells /* 81531143d5dSDavid Howells * flush any dirty pages for this process, and check for write errors. 81631143d5dSDavid Howells * - the return status from this call provides a reliable indication of 81731143d5dSDavid Howells * whether any write errors occurred for this process. 81831143d5dSDavid Howells */ 81902c24a82SJosef Bacik int afs_fsync(struct file *file, loff_t start, loff_t end, int datasync) 82031143d5dSDavid Howells { 8213c981bfcSAl Viro struct inode *inode = file_inode(file); 8223c981bfcSAl Viro struct afs_vnode *vnode = AFS_FS_I(inode); 82331143d5dSDavid Howells 8243b6492dfSDavid Howells _enter("{%llx:%llu},{n=%pD},%d", 8253c981bfcSAl Viro vnode->fid.vid, vnode->fid.vnode, file, 82631143d5dSDavid Howells datasync); 82731143d5dSDavid Howells 8284343d008SDavid Howells return file_write_and_wait_range(file, start, end); 82931143d5dSDavid Howells } 8309b3f26c9SDavid Howells 8319b3f26c9SDavid Howells /* 8329b3f26c9SDavid Howells * notification that a previously read-only page is about to become writable 8339b3f26c9SDavid Howells * - if it returns an error, the caller will deliver a bus error signal 8349b3f26c9SDavid Howells */ 8350722f186SSouptick Joarder vm_fault_t afs_page_mkwrite(struct vm_fault *vmf) 8369b3f26c9SDavid Howells { 8371cf7a151SDavid Howells struct file *file = vmf->vma->vm_file; 8381cf7a151SDavid Howells struct inode *inode = file_inode(file); 8391cf7a151SDavid Howells struct afs_vnode *vnode = AFS_FS_I(inode); 8401cf7a151SDavid Howells unsigned long priv; 8419b3f26c9SDavid Howells 8423b6492dfSDavid Howells _enter("{{%llx:%llu}},{%lx}", 8431cf7a151SDavid Howells vnode->fid.vid, vnode->fid.vnode, vmf->page->index); 8449b3f26c9SDavid Howells 8451cf7a151SDavid Howells sb_start_pagefault(inode->i_sb); 8461cf7a151SDavid Howells 8471cf7a151SDavid Howells /* Wait for the page to be written to the cache before we allow it to 8481cf7a151SDavid Howells * be modified. We then assume the entire page will need writing back. 8491cf7a151SDavid Howells */ 8509b3f26c9SDavid Howells #ifdef CONFIG_AFS_FSCACHE 8511cf7a151SDavid Howells fscache_wait_on_page_write(vnode->cache, vmf->page); 8529b3f26c9SDavid Howells #endif 8539b3f26c9SDavid Howells 854*75b69799SMatthew Wilcox (Oracle) if (wait_on_page_writeback_killable(vmf->page)) 8551cf7a151SDavid Howells return VM_FAULT_RETRY; 8561cf7a151SDavid Howells 8571cf7a151SDavid Howells if (lock_page_killable(vmf->page) < 0) 8581cf7a151SDavid Howells return VM_FAULT_RETRY; 8591cf7a151SDavid Howells 8601cf7a151SDavid Howells /* We mustn't change page->private until writeback is complete as that 8611cf7a151SDavid Howells * details the portion of the page we need to write back and we might 8621cf7a151SDavid Howells * need to redirty the page if there's a problem. 8631cf7a151SDavid Howells */ 8641cf7a151SDavid Howells wait_on_page_writeback(vmf->page); 8651cf7a151SDavid Howells 866185f0c70SDavid Howells priv = afs_page_dirty(0, PAGE_SIZE); 867f86726a6SDavid Howells priv = afs_page_dirty_mmapped(priv); 86813524ab3SDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("mkwrite"), 86913524ab3SDavid Howells vmf->page->index, priv); 870fa04a40bSDavid Howells if (PagePrivate(vmf->page)) 8711cf7a151SDavid Howells set_page_private(vmf->page, priv); 872fa04a40bSDavid Howells else 873fa04a40bSDavid Howells attach_page_private(vmf->page, (void *)priv); 874bb413489SDavid Howells file_update_time(file); 8751cf7a151SDavid Howells 8761cf7a151SDavid Howells sb_end_pagefault(inode->i_sb); 8771cf7a151SDavid Howells return VM_FAULT_LOCKED; 8789b3f26c9SDavid Howells } 8794343d008SDavid Howells 8804343d008SDavid Howells /* 8814343d008SDavid Howells * Prune the keys cached for writeback. The caller must hold vnode->wb_lock. 8824343d008SDavid Howells */ 8834343d008SDavid Howells void afs_prune_wb_keys(struct afs_vnode *vnode) 8844343d008SDavid Howells { 8854343d008SDavid Howells LIST_HEAD(graveyard); 8864343d008SDavid Howells struct afs_wb_key *wbk, *tmp; 8874343d008SDavid Howells 8884343d008SDavid Howells /* Discard unused keys */ 8894343d008SDavid Howells spin_lock(&vnode->wb_lock); 8904343d008SDavid Howells 8914343d008SDavid Howells if (!mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_WRITEBACK) && 8924343d008SDavid Howells !mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_DIRTY)) { 8934343d008SDavid Howells list_for_each_entry_safe(wbk, tmp, &vnode->wb_keys, vnode_link) { 8944343d008SDavid Howells if (refcount_read(&wbk->usage) == 1) 8954343d008SDavid Howells list_move(&wbk->vnode_link, &graveyard); 8964343d008SDavid Howells } 8974343d008SDavid Howells } 8984343d008SDavid Howells 8994343d008SDavid Howells spin_unlock(&vnode->wb_lock); 9004343d008SDavid Howells 9014343d008SDavid Howells while (!list_empty(&graveyard)) { 9024343d008SDavid Howells wbk = list_entry(graveyard.next, struct afs_wb_key, vnode_link); 9034343d008SDavid Howells list_del(&wbk->vnode_link); 9044343d008SDavid Howells afs_put_wb_key(wbk); 9054343d008SDavid Howells } 9064343d008SDavid Howells } 9074343d008SDavid Howells 9084343d008SDavid Howells /* 9094343d008SDavid Howells * Clean up a page during invalidation. 9104343d008SDavid Howells */ 9114343d008SDavid Howells int afs_launder_page(struct page *page) 9124343d008SDavid Howells { 9134343d008SDavid Howells struct address_space *mapping = page->mapping; 9144343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 9154343d008SDavid Howells unsigned long priv; 9164343d008SDavid Howells unsigned int f, t; 9174343d008SDavid Howells int ret = 0; 9184343d008SDavid Howells 9194343d008SDavid Howells _enter("{%lx}", page->index); 9204343d008SDavid Howells 9214343d008SDavid Howells priv = page_private(page); 9224343d008SDavid Howells if (clear_page_dirty_for_io(page)) { 9234343d008SDavid Howells f = 0; 9244343d008SDavid Howells t = PAGE_SIZE; 9254343d008SDavid Howells if (PagePrivate(page)) { 926185f0c70SDavid Howells f = afs_page_dirty_from(priv); 927185f0c70SDavid Howells t = afs_page_dirty_to(priv); 9284343d008SDavid Howells } 9294343d008SDavid Howells 93013524ab3SDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("launder"), 93113524ab3SDavid Howells page->index, priv); 932d383e346SDavid Howells ret = afs_store_data(mapping, page->index, page->index, t, f, true); 9334343d008SDavid Howells } 9344343d008SDavid Howells 935fa04a40bSDavid Howells priv = (unsigned long)detach_page_private(page); 93613524ab3SDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("laundered"), 93713524ab3SDavid Howells page->index, priv); 9384343d008SDavid Howells 9394343d008SDavid Howells #ifdef CONFIG_AFS_FSCACHE 9404343d008SDavid Howells if (PageFsCache(page)) { 9414343d008SDavid Howells fscache_wait_on_page_write(vnode->cache, page); 9424343d008SDavid Howells fscache_uncache_page(vnode->cache, page); 9434343d008SDavid Howells } 9444343d008SDavid Howells #endif 9454343d008SDavid Howells return ret; 94631143d5dSDavid Howells } 947