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 /* 26c4508464SDavid Howells * Handle completion of a read operation to fill a page. 27c4508464SDavid Howells */ 28c4508464SDavid Howells static void afs_fill_hole(struct afs_read *req) 29c4508464SDavid Howells { 30c4508464SDavid Howells if (iov_iter_count(req->iter) > 0) 31c4508464SDavid Howells /* The read was short - clear the excess buffer. */ 32c4508464SDavid Howells iov_iter_zero(iov_iter_count(req->iter), req->iter); 33c4508464SDavid Howells } 34c4508464SDavid Howells 35c4508464SDavid Howells /* 3631143d5dSDavid Howells * partly or wholly fill a page that's under preparation for writing 3731143d5dSDavid Howells */ 38c69bf479SDavid Howells static int afs_fill_page(struct file *file, 39e8e581a8SDavid Howells loff_t pos, unsigned int len, struct page *page) 4031143d5dSDavid Howells { 41c69bf479SDavid Howells struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); 42196ee9cdSDavid Howells struct afs_read *req; 432a0b4f64SDavid Howells size_t p; 442a0b4f64SDavid Howells void *data; 4531143d5dSDavid Howells int ret; 4631143d5dSDavid Howells 475e7f2337SAnton Blanchard _enter(",,%llu", (unsigned long long)pos); 4831143d5dSDavid Howells 492a0b4f64SDavid Howells if (pos >= vnode->vfs_inode.i_size) { 502a0b4f64SDavid Howells p = pos & ~PAGE_MASK; 512a0b4f64SDavid Howells ASSERTCMP(p + len, <=, PAGE_SIZE); 522a0b4f64SDavid Howells data = kmap(page); 532a0b4f64SDavid Howells memset(data + p, 0, len); 542a0b4f64SDavid Howells kunmap(page); 552a0b4f64SDavid Howells return 0; 562a0b4f64SDavid Howells } 572a0b4f64SDavid Howells 58c4508464SDavid Howells req = kzalloc(sizeof(struct afs_read), GFP_KERNEL); 59196ee9cdSDavid Howells if (!req) 60196ee9cdSDavid Howells return -ENOMEM; 61196ee9cdSDavid Howells 62f3ddee8dSDavid Howells refcount_set(&req->usage, 1); 63c4508464SDavid Howells req->vnode = vnode; 64c4508464SDavid Howells req->done = afs_fill_hole; 65c69bf479SDavid Howells req->key = key_get(afs_file_key(file)); 66196ee9cdSDavid Howells req->pos = pos; 67e8e581a8SDavid Howells req->len = len; 68196ee9cdSDavid Howells req->nr_pages = 1; 69c4508464SDavid Howells req->iter = &req->def_iter; 70c4508464SDavid Howells iov_iter_xarray(&req->def_iter, READ, &file->f_mapping->i_pages, pos, len); 71196ee9cdSDavid Howells 72c69bf479SDavid Howells ret = afs_fetch_data(vnode, req); 73196ee9cdSDavid Howells afs_put_read(req); 7431143d5dSDavid Howells if (ret < 0) { 7531143d5dSDavid Howells if (ret == -ENOENT) { 7631143d5dSDavid Howells _debug("got NOENT from server" 7731143d5dSDavid Howells " - marking file deleted and stale"); 7831143d5dSDavid Howells set_bit(AFS_VNODE_DELETED, &vnode->flags); 7931143d5dSDavid Howells ret = -ESTALE; 8031143d5dSDavid Howells } 8131143d5dSDavid Howells } 8231143d5dSDavid Howells 8331143d5dSDavid Howells _leave(" = %d", ret); 8431143d5dSDavid Howells return ret; 8531143d5dSDavid Howells } 8631143d5dSDavid Howells 8731143d5dSDavid Howells /* 8831143d5dSDavid Howells * prepare to perform part of a write to a page 8931143d5dSDavid Howells */ 9015b4650eSNick Piggin int afs_write_begin(struct file *file, struct address_space *mapping, 9115b4650eSNick Piggin loff_t pos, unsigned len, unsigned flags, 9221db2cdcSDavid Howells struct page **_page, void **fsdata) 9331143d5dSDavid Howells { 94496ad9aaSAl Viro struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); 9515b4650eSNick Piggin struct page *page; 964343d008SDavid Howells unsigned long priv; 974343d008SDavid Howells unsigned f, from = pos & (PAGE_SIZE - 1); 984343d008SDavid Howells unsigned t, to = from + len; 9909cbfeafSKirill A. Shutemov pgoff_t index = pos >> PAGE_SHIFT; 10031143d5dSDavid Howells int ret; 10131143d5dSDavid Howells 1023b6492dfSDavid Howells _enter("{%llx:%llu},{%lx},%u,%u", 10315b4650eSNick Piggin vnode->fid.vid, vnode->fid.vnode, index, from, to); 10431143d5dSDavid Howells 10554566b2cSNick Piggin page = grab_cache_page_write_begin(mapping, index, flags); 1064343d008SDavid Howells if (!page) 10715b4650eSNick Piggin return -ENOMEM; 10815b4650eSNick Piggin 10909cbfeafSKirill A. Shutemov if (!PageUptodate(page) && len != PAGE_SIZE) { 110c69bf479SDavid Howells ret = afs_fill_page(file, pos & PAGE_MASK, PAGE_SIZE, page); 11131143d5dSDavid Howells if (ret < 0) { 1126d06b0d2SDavid Howells unlock_page(page); 1136d06b0d2SDavid Howells put_page(page); 11431143d5dSDavid Howells _leave(" = %d [prep]", ret); 11531143d5dSDavid Howells return ret; 11631143d5dSDavid Howells } 11715b4650eSNick Piggin SetPageUptodate(page); 11831143d5dSDavid Howells } 11931143d5dSDavid Howells 120*630f5ddaSDavid Howells #ifdef CONFIG_AFS_FSCACHE 121*630f5ddaSDavid Howells wait_on_page_fscache(page); 122*630f5ddaSDavid Howells #endif 123*630f5ddaSDavid Howells 12431143d5dSDavid Howells try_again: 1254343d008SDavid Howells /* See if this page is already partially written in a way that we can 1264343d008SDavid Howells * merge the new write with. 1274343d008SDavid Howells */ 1284343d008SDavid Howells t = f = 0; 1294343d008SDavid Howells if (PagePrivate(page)) { 1304343d008SDavid Howells priv = page_private(page); 13167d78a6fSDavid Howells f = afs_page_dirty_from(page, priv); 13267d78a6fSDavid Howells t = afs_page_dirty_to(page, priv); 1334343d008SDavid Howells ASSERTCMP(f, <=, t); 13431143d5dSDavid Howells } 13531143d5dSDavid Howells 1364343d008SDavid Howells if (f != t) { 1375a039c32SDavid Howells if (PageWriteback(page)) { 13867d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("alrdy"), page); 1395a039c32SDavid Howells goto flush_conflicting_write; 1405a039c32SDavid Howells } 1415a813276SDavid Howells /* If the file is being filled locally, allow inter-write 1425a813276SDavid Howells * spaces to be merged into writes. If it's not, only write 1435a813276SDavid Howells * back what the user gives us. 1445a813276SDavid Howells */ 1455a813276SDavid Howells if (!test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags) && 1465a813276SDavid Howells (to < f || from > t)) 1474343d008SDavid Howells goto flush_conflicting_write; 14831143d5dSDavid Howells } 14931143d5dSDavid Howells 15021db2cdcSDavid Howells *_page = page; 1514343d008SDavid Howells _leave(" = 0"); 15231143d5dSDavid Howells return 0; 15331143d5dSDavid Howells 1544343d008SDavid Howells /* The previous write and this write aren't adjacent or overlapping, so 1554343d008SDavid Howells * flush the page out. 1564343d008SDavid Howells */ 1574343d008SDavid Howells flush_conflicting_write: 15831143d5dSDavid Howells _debug("flush conflict"); 1594343d008SDavid Howells ret = write_one_page(page); 16021db2cdcSDavid Howells if (ret < 0) 16121db2cdcSDavid Howells goto error; 16231143d5dSDavid Howells 1634343d008SDavid Howells ret = lock_page_killable(page); 16421db2cdcSDavid Howells if (ret < 0) 16521db2cdcSDavid Howells goto error; 16621db2cdcSDavid Howells goto try_again; 16721db2cdcSDavid Howells 16821db2cdcSDavid Howells error: 16921db2cdcSDavid Howells put_page(page); 1704343d008SDavid Howells _leave(" = %d", ret); 1714343d008SDavid Howells return ret; 1724343d008SDavid Howells } 17331143d5dSDavid Howells 17431143d5dSDavid Howells /* 17531143d5dSDavid Howells * finalise part of a write to a page 17631143d5dSDavid Howells */ 17715b4650eSNick Piggin int afs_write_end(struct file *file, struct address_space *mapping, 17815b4650eSNick Piggin loff_t pos, unsigned len, unsigned copied, 17915b4650eSNick Piggin struct page *page, void *fsdata) 18031143d5dSDavid Howells { 181496ad9aaSAl Viro struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); 182f792e3acSDavid Howells unsigned long priv; 183f792e3acSDavid Howells unsigned int f, from = pos & (PAGE_SIZE - 1); 184f792e3acSDavid Howells unsigned int t, to = from + copied; 18531143d5dSDavid Howells loff_t i_size, maybe_i_size; 1863ad216eeSDavid Howells int ret = 0; 18731143d5dSDavid Howells 1883b6492dfSDavid Howells _enter("{%llx:%llu},{%lx}", 18915b4650eSNick Piggin vnode->fid.vid, vnode->fid.vnode, page->index); 19031143d5dSDavid Howells 1913ad216eeSDavid Howells if (copied == 0) 1923ad216eeSDavid Howells goto out; 1933ad216eeSDavid Howells 19415b4650eSNick Piggin maybe_i_size = pos + copied; 19531143d5dSDavid Howells 19631143d5dSDavid Howells i_size = i_size_read(&vnode->vfs_inode); 19731143d5dSDavid Howells if (maybe_i_size > i_size) { 1981f32ef79SDavid Howells write_seqlock(&vnode->cb_lock); 19931143d5dSDavid Howells i_size = i_size_read(&vnode->vfs_inode); 20031143d5dSDavid Howells if (maybe_i_size > i_size) 20131143d5dSDavid Howells i_size_write(&vnode->vfs_inode, maybe_i_size); 2021f32ef79SDavid Howells write_sequnlock(&vnode->cb_lock); 20331143d5dSDavid Howells } 20431143d5dSDavid Howells 205e8e581a8SDavid Howells if (!PageUptodate(page)) { 206e8e581a8SDavid Howells if (copied < len) { 207e8e581a8SDavid Howells /* Try and load any missing data from the server. The 208e8e581a8SDavid Howells * unmarshalling routine will take care of clearing any 209e8e581a8SDavid Howells * bits that are beyond the EOF. 210e8e581a8SDavid Howells */ 211c69bf479SDavid Howells ret = afs_fill_page(file, pos + copied, 212e8e581a8SDavid Howells len - copied, page); 213e8e581a8SDavid Howells if (ret < 0) 214afae457dSDavid Howells goto out; 215e8e581a8SDavid Howells } 216e8e581a8SDavid Howells SetPageUptodate(page); 217e8e581a8SDavid Howells } 218e8e581a8SDavid Howells 219f792e3acSDavid Howells if (PagePrivate(page)) { 220f792e3acSDavid Howells priv = page_private(page); 22167d78a6fSDavid Howells f = afs_page_dirty_from(page, priv); 22267d78a6fSDavid Howells t = afs_page_dirty_to(page, priv); 223f792e3acSDavid Howells if (from < f) 224f792e3acSDavid Howells f = from; 225f792e3acSDavid Howells if (to > t) 226f792e3acSDavid Howells t = to; 22767d78a6fSDavid Howells priv = afs_page_dirty(page, f, t); 228f792e3acSDavid Howells set_page_private(page, priv); 22967d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("dirty+"), page); 230f792e3acSDavid Howells } else { 23167d78a6fSDavid Howells priv = afs_page_dirty(page, from, to); 232f792e3acSDavid Howells attach_page_private(page, (void *)priv); 23367d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("dirty"), page); 234f792e3acSDavid Howells } 235f792e3acSDavid Howells 23631143d5dSDavid Howells set_page_dirty(page); 23731143d5dSDavid Howells if (PageDirty(page)) 23831143d5dSDavid Howells _debug("dirtied"); 239afae457dSDavid Howells ret = copied; 240afae457dSDavid Howells 241afae457dSDavid Howells out: 24215b4650eSNick Piggin unlock_page(page); 24309cbfeafSKirill A. Shutemov put_page(page); 244afae457dSDavid Howells return ret; 24531143d5dSDavid Howells } 24631143d5dSDavid Howells 24731143d5dSDavid Howells /* 24831143d5dSDavid Howells * kill all the pages in the given range 24931143d5dSDavid Howells */ 2504343d008SDavid Howells static void afs_kill_pages(struct address_space *mapping, 25131143d5dSDavid Howells pgoff_t first, pgoff_t last) 25231143d5dSDavid Howells { 2534343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 25431143d5dSDavid Howells struct pagevec pv; 25531143d5dSDavid Howells unsigned count, loop; 25631143d5dSDavid Howells 2573b6492dfSDavid Howells _enter("{%llx:%llu},%lx-%lx", 25831143d5dSDavid Howells vnode->fid.vid, vnode->fid.vnode, first, last); 25931143d5dSDavid Howells 26086679820SMel Gorman pagevec_init(&pv); 26131143d5dSDavid Howells 26231143d5dSDavid Howells do { 26331143d5dSDavid Howells _debug("kill %lx-%lx", first, last); 26431143d5dSDavid Howells 26531143d5dSDavid Howells count = last - first + 1; 26631143d5dSDavid Howells if (count > PAGEVEC_SIZE) 26731143d5dSDavid Howells count = PAGEVEC_SIZE; 2684343d008SDavid Howells pv.nr = find_get_pages_contig(mapping, first, count, pv.pages); 26931143d5dSDavid Howells ASSERTCMP(pv.nr, ==, count); 27031143d5dSDavid Howells 27131143d5dSDavid Howells for (loop = 0; loop < count; loop++) { 2727286a35eSDavid Howells struct page *page = pv.pages[loop]; 2737286a35eSDavid Howells ClearPageUptodate(page); 2747286a35eSDavid Howells SetPageError(page); 2754343d008SDavid Howells end_page_writeback(page); 2764343d008SDavid Howells if (page->index >= first) 2774343d008SDavid Howells first = page->index + 1; 2784343d008SDavid Howells lock_page(page); 2794343d008SDavid Howells generic_error_remove_page(mapping, page); 28021bd68f1SMarc Dionne unlock_page(page); 2814343d008SDavid Howells } 2824343d008SDavid Howells 2834343d008SDavid Howells __pagevec_release(&pv); 2844343d008SDavid Howells } while (first <= last); 2854343d008SDavid Howells 2864343d008SDavid Howells _leave(""); 2874343d008SDavid Howells } 2884343d008SDavid Howells 2894343d008SDavid Howells /* 2904343d008SDavid Howells * Redirty all the pages in a given range. 2914343d008SDavid Howells */ 2924343d008SDavid Howells static void afs_redirty_pages(struct writeback_control *wbc, 2934343d008SDavid Howells struct address_space *mapping, 2944343d008SDavid Howells pgoff_t first, pgoff_t last) 2954343d008SDavid Howells { 2964343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 2974343d008SDavid Howells struct pagevec pv; 2984343d008SDavid Howells unsigned count, loop; 2994343d008SDavid Howells 3003b6492dfSDavid Howells _enter("{%llx:%llu},%lx-%lx", 3014343d008SDavid Howells vnode->fid.vid, vnode->fid.vnode, first, last); 3024343d008SDavid Howells 303487e2c9fSLinus Torvalds pagevec_init(&pv); 3044343d008SDavid Howells 3054343d008SDavid Howells do { 3064343d008SDavid Howells _debug("redirty %lx-%lx", first, last); 3074343d008SDavid Howells 3084343d008SDavid Howells count = last - first + 1; 3094343d008SDavid Howells if (count > PAGEVEC_SIZE) 3104343d008SDavid Howells count = PAGEVEC_SIZE; 3114343d008SDavid Howells pv.nr = find_get_pages_contig(mapping, first, count, pv.pages); 3124343d008SDavid Howells ASSERTCMP(pv.nr, ==, count); 3134343d008SDavid Howells 3144343d008SDavid Howells for (loop = 0; loop < count; loop++) { 3154343d008SDavid Howells struct page *page = pv.pages[loop]; 3164343d008SDavid Howells 3174343d008SDavid Howells redirty_page_for_writepage(wbc, page); 3187286a35eSDavid Howells end_page_writeback(page); 3197286a35eSDavid Howells if (page->index >= first) 3207286a35eSDavid Howells first = page->index + 1; 32131143d5dSDavid Howells } 32231143d5dSDavid Howells 32331143d5dSDavid Howells __pagevec_release(&pv); 3244343d008SDavid Howells } while (first <= last); 32531143d5dSDavid Howells 32631143d5dSDavid Howells _leave(""); 32731143d5dSDavid Howells } 32831143d5dSDavid Howells 32931143d5dSDavid Howells /* 330a58823acSDavid Howells * completion of write to server 331a58823acSDavid Howells */ 332bd80d8a8SDavid Howells static void afs_pages_written_back(struct afs_vnode *vnode, pgoff_t start, pgoff_t last) 333a58823acSDavid Howells { 334bd80d8a8SDavid Howells struct address_space *mapping = vnode->vfs_inode.i_mapping; 335bd80d8a8SDavid Howells struct page *page; 336bd80d8a8SDavid Howells 337bd80d8a8SDavid Howells XA_STATE(xas, &mapping->i_pages, start); 338a58823acSDavid Howells 339a58823acSDavid Howells _enter("{%llx:%llu},{%lx-%lx}", 340bd80d8a8SDavid Howells vnode->fid.vid, vnode->fid.vnode, start, last); 341a58823acSDavid Howells 342bd80d8a8SDavid Howells rcu_read_lock(); 343a58823acSDavid Howells 344bd80d8a8SDavid Howells xas_for_each(&xas, page, last) { 345bd80d8a8SDavid Howells ASSERT(PageWriteback(page)); 346a58823acSDavid Howells 347bd80d8a8SDavid Howells detach_page_private(page); 348bd80d8a8SDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("clear"), page); 349bd80d8a8SDavid Howells page_endio(page, true, 0); 350a58823acSDavid Howells } 351bd80d8a8SDavid Howells 352bd80d8a8SDavid Howells rcu_read_unlock(); 353a58823acSDavid Howells 354a58823acSDavid Howells afs_prune_wb_keys(vnode); 355a58823acSDavid Howells _leave(""); 356a58823acSDavid Howells } 357a58823acSDavid Howells 358a58823acSDavid Howells /* 359e49c7b2fSDavid Howells * Find a key to use for the writeback. We cached the keys used to author the 360e49c7b2fSDavid Howells * writes on the vnode. *_wbk will contain the last writeback key used or NULL 361e49c7b2fSDavid Howells * and we need to start from there if it's set. 362e49c7b2fSDavid Howells */ 363e49c7b2fSDavid Howells static int afs_get_writeback_key(struct afs_vnode *vnode, 364e49c7b2fSDavid Howells struct afs_wb_key **_wbk) 365e49c7b2fSDavid Howells { 366e49c7b2fSDavid Howells struct afs_wb_key *wbk = NULL; 367e49c7b2fSDavid Howells struct list_head *p; 368e49c7b2fSDavid Howells int ret = -ENOKEY, ret2; 369e49c7b2fSDavid Howells 370e49c7b2fSDavid Howells spin_lock(&vnode->wb_lock); 371e49c7b2fSDavid Howells if (*_wbk) 372e49c7b2fSDavid Howells p = (*_wbk)->vnode_link.next; 373e49c7b2fSDavid Howells else 374e49c7b2fSDavid Howells p = vnode->wb_keys.next; 375e49c7b2fSDavid Howells 376e49c7b2fSDavid Howells while (p != &vnode->wb_keys) { 377e49c7b2fSDavid Howells wbk = list_entry(p, struct afs_wb_key, vnode_link); 378e49c7b2fSDavid Howells _debug("wbk %u", key_serial(wbk->key)); 379e49c7b2fSDavid Howells ret2 = key_validate(wbk->key); 380e49c7b2fSDavid Howells if (ret2 == 0) { 381e49c7b2fSDavid Howells refcount_inc(&wbk->usage); 382e49c7b2fSDavid Howells _debug("USE WB KEY %u", key_serial(wbk->key)); 383e49c7b2fSDavid Howells break; 384e49c7b2fSDavid Howells } 385e49c7b2fSDavid Howells 386e49c7b2fSDavid Howells wbk = NULL; 387e49c7b2fSDavid Howells if (ret == -ENOKEY) 388e49c7b2fSDavid Howells ret = ret2; 389e49c7b2fSDavid Howells p = p->next; 390e49c7b2fSDavid Howells } 391e49c7b2fSDavid Howells 392e49c7b2fSDavid Howells spin_unlock(&vnode->wb_lock); 393e49c7b2fSDavid Howells if (*_wbk) 394e49c7b2fSDavid Howells afs_put_wb_key(*_wbk); 395e49c7b2fSDavid Howells *_wbk = wbk; 396e49c7b2fSDavid Howells return 0; 397e49c7b2fSDavid Howells } 398e49c7b2fSDavid Howells 399e49c7b2fSDavid Howells static void afs_store_data_success(struct afs_operation *op) 400e49c7b2fSDavid Howells { 401e49c7b2fSDavid Howells struct afs_vnode *vnode = op->file[0].vnode; 402e49c7b2fSDavid Howells 403da8d0755SDavid Howells op->ctime = op->file[0].scb.status.mtime_client; 404e49c7b2fSDavid Howells afs_vnode_commit_status(op, &op->file[0]); 405e49c7b2fSDavid Howells if (op->error == 0) { 406d383e346SDavid Howells if (!op->store.laundering) 407e49c7b2fSDavid Howells afs_pages_written_back(vnode, op->store.first, op->store.last); 408e49c7b2fSDavid Howells afs_stat_v(vnode, n_stores); 409bd80d8a8SDavid Howells atomic_long_add(op->store.size, &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 */ 422bd80d8a8SDavid Howells static int afs_store_data(struct afs_vnode *vnode, struct iov_iter *iter, 423bd80d8a8SDavid Howells loff_t pos, pgoff_t first, pgoff_t last, 424bd80d8a8SDavid Howells bool laundering) 42531143d5dSDavid Howells { 426e49c7b2fSDavid Howells struct afs_operation *op; 4274343d008SDavid Howells struct afs_wb_key *wbk = NULL; 428bd80d8a8SDavid Howells loff_t size = iov_iter_count(iter), i_size; 429bd80d8a8SDavid Howells int ret = -ENOKEY; 430d2ddc776SDavid Howells 431bd80d8a8SDavid Howells _enter("%s{%llx:%llu.%u},%llx,%llx", 432d2ddc776SDavid Howells vnode->volume->name, 433d2ddc776SDavid Howells vnode->fid.vid, 434d2ddc776SDavid Howells vnode->fid.vnode, 435d2ddc776SDavid Howells vnode->fid.unique, 436bd80d8a8SDavid Howells size, pos); 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 450bd80d8a8SDavid Howells i_size = i_size_read(&vnode->vfs_inode); 451bd80d8a8SDavid Howells 452e49c7b2fSDavid Howells afs_op_set_vnode(op, 0, vnode); 453e49c7b2fSDavid Howells op->file[0].dv_delta = 1; 454bd80d8a8SDavid Howells op->store.write_iter = iter; 455bd80d8a8SDavid Howells op->store.pos = pos; 456e49c7b2fSDavid Howells op->store.first = first; 457e49c7b2fSDavid Howells op->store.last = last; 458bd80d8a8SDavid Howells op->store.size = size; 459bd80d8a8SDavid Howells op->store.i_size = max(pos + size, i_size); 460d383e346SDavid Howells op->store.laundering = laundering; 461b3597945SDavid Howells op->mtime = vnode->vfs_inode.i_mtime; 462811f04baSDavid Howells op->flags |= AFS_OPERATION_UNINTR; 463e49c7b2fSDavid Howells op->ops = &afs_store_data_operation; 464e49c7b2fSDavid Howells 465e49c7b2fSDavid Howells try_next_key: 466e49c7b2fSDavid Howells afs_begin_vnode_operation(op); 467e49c7b2fSDavid Howells afs_wait_for_operation(op); 468e49c7b2fSDavid Howells 469e49c7b2fSDavid Howells switch (op->error) { 4704343d008SDavid Howells case -EACCES: 4714343d008SDavid Howells case -EPERM: 4724343d008SDavid Howells case -ENOKEY: 4734343d008SDavid Howells case -EKEYEXPIRED: 4744343d008SDavid Howells case -EKEYREJECTED: 4754343d008SDavid Howells case -EKEYREVOKED: 4764343d008SDavid Howells _debug("next"); 477e49c7b2fSDavid Howells 478e49c7b2fSDavid Howells ret = afs_get_writeback_key(vnode, &wbk); 479e49c7b2fSDavid Howells if (ret == 0) { 480e49c7b2fSDavid Howells key_put(op->key); 481e49c7b2fSDavid Howells op->key = key_get(wbk->key); 4824343d008SDavid Howells goto try_next_key; 4834343d008SDavid Howells } 484e49c7b2fSDavid Howells break; 485e49c7b2fSDavid Howells } 4864343d008SDavid Howells 4874343d008SDavid Howells afs_put_wb_key(wbk); 488e49c7b2fSDavid Howells _leave(" = %d", op->error); 489e49c7b2fSDavid Howells return afs_put_operation(op); 490d2ddc776SDavid Howells } 491d2ddc776SDavid Howells 492d2ddc776SDavid Howells /* 4934343d008SDavid Howells * Synchronously write back the locked page and any subsequent non-locked dirty 4944343d008SDavid Howells * pages. 49531143d5dSDavid Howells */ 4964343d008SDavid Howells static int afs_write_back_from_locked_page(struct address_space *mapping, 4974343d008SDavid Howells struct writeback_control *wbc, 4984343d008SDavid Howells struct page *primary_page, 4994343d008SDavid Howells pgoff_t final_page) 50031143d5dSDavid Howells { 50113524ab3SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 502bd80d8a8SDavid Howells struct iov_iter iter; 50331143d5dSDavid Howells struct page *pages[8], *page; 5044343d008SDavid Howells unsigned long count, priv; 5054343d008SDavid Howells unsigned n, offset, to, f, t; 50631143d5dSDavid Howells pgoff_t start, first, last; 507bd80d8a8SDavid Howells loff_t i_size, pos, end; 50831143d5dSDavid Howells int loop, ret; 50931143d5dSDavid Howells 51031143d5dSDavid Howells _enter(",%lx", primary_page->index); 51131143d5dSDavid Howells 51231143d5dSDavid Howells count = 1; 51331143d5dSDavid Howells if (test_set_page_writeback(primary_page)) 51431143d5dSDavid Howells BUG(); 51531143d5dSDavid Howells 5164343d008SDavid Howells /* Find all consecutive lockable dirty pages that have contiguous 5174343d008SDavid Howells * written regions, stopping when we find a page that is not 5184343d008SDavid Howells * immediately lockable, is not dirty or is missing, or we reach the 5194343d008SDavid Howells * end of the range. 5204343d008SDavid Howells */ 52131143d5dSDavid Howells start = primary_page->index; 5224343d008SDavid Howells priv = page_private(primary_page); 52367d78a6fSDavid Howells offset = afs_page_dirty_from(primary_page, priv); 52467d78a6fSDavid Howells to = afs_page_dirty_to(primary_page, priv); 52567d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("store"), primary_page); 5264343d008SDavid Howells 5274343d008SDavid Howells WARN_ON(offset == to); 52813524ab3SDavid Howells if (offset == to) 52967d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("WARN"), primary_page); 5304343d008SDavid Howells 5315a813276SDavid Howells if (start >= final_page || 5325a813276SDavid Howells (to < PAGE_SIZE && !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags))) 53331143d5dSDavid Howells goto no_more; 5344343d008SDavid Howells 53531143d5dSDavid Howells start++; 53631143d5dSDavid Howells do { 53731143d5dSDavid Howells _debug("more %lx [%lx]", start, count); 5384343d008SDavid Howells n = final_page - start + 1; 53931143d5dSDavid Howells if (n > ARRAY_SIZE(pages)) 54031143d5dSDavid Howells n = ARRAY_SIZE(pages); 5414343d008SDavid Howells n = find_get_pages_contig(mapping, start, ARRAY_SIZE(pages), pages); 54231143d5dSDavid Howells _debug("fgpc %u", n); 54331143d5dSDavid Howells if (n == 0) 54431143d5dSDavid Howells goto no_more; 54531143d5dSDavid Howells if (pages[0]->index != start) { 5469d577b6aSDavid Howells do { 5479d577b6aSDavid Howells put_page(pages[--n]); 5489d577b6aSDavid Howells } while (n > 0); 54931143d5dSDavid Howells goto no_more; 55031143d5dSDavid Howells } 55131143d5dSDavid Howells 55231143d5dSDavid Howells for (loop = 0; loop < n; loop++) { 55331143d5dSDavid Howells page = pages[loop]; 5545a813276SDavid Howells if (to != PAGE_SIZE && 5555a813276SDavid Howells !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)) 5565a813276SDavid Howells break; 5574343d008SDavid Howells if (page->index > final_page) 55831143d5dSDavid Howells break; 559529ae9aaSNick Piggin if (!trylock_page(page)) 56031143d5dSDavid Howells break; 5614343d008SDavid Howells if (!PageDirty(page) || PageWriteback(page)) { 56231143d5dSDavid Howells unlock_page(page); 56331143d5dSDavid Howells break; 56431143d5dSDavid Howells } 5654343d008SDavid Howells 5664343d008SDavid Howells priv = page_private(page); 56767d78a6fSDavid Howells f = afs_page_dirty_from(page, priv); 56867d78a6fSDavid Howells t = afs_page_dirty_to(page, priv); 5695a813276SDavid Howells if (f != 0 && 5705a813276SDavid Howells !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)) { 5714343d008SDavid Howells unlock_page(page); 5724343d008SDavid Howells break; 5734343d008SDavid Howells } 5744343d008SDavid Howells to = t; 5754343d008SDavid Howells 57667d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("store+"), page); 57713524ab3SDavid Howells 57831143d5dSDavid Howells if (!clear_page_dirty_for_io(page)) 57931143d5dSDavid Howells BUG(); 58031143d5dSDavid Howells if (test_set_page_writeback(page)) 58131143d5dSDavid Howells BUG(); 58231143d5dSDavid Howells unlock_page(page); 58331143d5dSDavid Howells put_page(page); 58431143d5dSDavid Howells } 58531143d5dSDavid Howells count += loop; 58631143d5dSDavid Howells if (loop < n) { 58731143d5dSDavid Howells for (; loop < n; loop++) 58831143d5dSDavid Howells put_page(pages[loop]); 58931143d5dSDavid Howells goto no_more; 59031143d5dSDavid Howells } 59131143d5dSDavid Howells 59231143d5dSDavid Howells start += loop; 5934343d008SDavid Howells } while (start <= final_page && count < 65536); 59431143d5dSDavid Howells 59531143d5dSDavid Howells no_more: 5964343d008SDavid Howells /* We now have a contiguous set of dirty pages, each with writeback 5974343d008SDavid Howells * set; the first page is still locked at this point, but all the rest 5984343d008SDavid Howells * have been unlocked. 5994343d008SDavid Howells */ 6004343d008SDavid Howells unlock_page(primary_page); 6014343d008SDavid Howells 60231143d5dSDavid Howells first = primary_page->index; 60331143d5dSDavid Howells last = first + count - 1; 60431143d5dSDavid Howells _debug("write back %lx[%u..] to %lx[..%u]", first, offset, last, to); 60531143d5dSDavid Howells 606bd80d8a8SDavid Howells pos = first; 607bd80d8a8SDavid Howells pos <<= PAGE_SHIFT; 608bd80d8a8SDavid Howells pos += offset; 609bd80d8a8SDavid Howells end = last; 610bd80d8a8SDavid Howells end <<= PAGE_SHIFT; 611bd80d8a8SDavid Howells end += to; 612bd80d8a8SDavid Howells 613bd80d8a8SDavid Howells /* Trim the actual write down to the EOF */ 614bd80d8a8SDavid Howells i_size = i_size_read(&vnode->vfs_inode); 615bd80d8a8SDavid Howells if (end > i_size) 616bd80d8a8SDavid Howells end = i_size; 617bd80d8a8SDavid Howells 618bd80d8a8SDavid Howells if (pos < i_size) { 619bd80d8a8SDavid Howells iov_iter_xarray(&iter, WRITE, &mapping->i_pages, pos, end - pos); 620bd80d8a8SDavid Howells ret = afs_store_data(vnode, &iter, pos, first, last, false); 621bd80d8a8SDavid Howells } else { 622bd80d8a8SDavid Howells /* The dirty region was entirely beyond the EOF. */ 623bd80d8a8SDavid Howells ret = 0; 624bd80d8a8SDavid Howells } 625bd80d8a8SDavid Howells 62631143d5dSDavid Howells switch (ret) { 6274343d008SDavid Howells case 0: 6284343d008SDavid Howells ret = count; 6294343d008SDavid Howells break; 6304343d008SDavid Howells 6314343d008SDavid Howells default: 6324343d008SDavid Howells pr_notice("kAFS: Unexpected error from FS.StoreData %d\n", ret); 633df561f66SGustavo A. R. Silva fallthrough; 6344343d008SDavid Howells case -EACCES: 6354343d008SDavid Howells case -EPERM: 6364343d008SDavid Howells case -ENOKEY: 6374343d008SDavid Howells case -EKEYEXPIRED: 6384343d008SDavid Howells case -EKEYREJECTED: 6394343d008SDavid Howells case -EKEYREVOKED: 6404343d008SDavid Howells afs_redirty_pages(wbc, mapping, first, last); 6414343d008SDavid Howells mapping_set_error(mapping, ret); 6424343d008SDavid Howells break; 6434343d008SDavid Howells 64431143d5dSDavid Howells case -EDQUOT: 64531143d5dSDavid Howells case -ENOSPC: 6464343d008SDavid Howells afs_redirty_pages(wbc, mapping, first, last); 6474343d008SDavid Howells mapping_set_error(mapping, -ENOSPC); 64831143d5dSDavid Howells break; 6494343d008SDavid Howells 65031143d5dSDavid Howells case -EROFS: 65131143d5dSDavid Howells case -EIO: 65231143d5dSDavid Howells case -EREMOTEIO: 65331143d5dSDavid Howells case -EFBIG: 65431143d5dSDavid Howells case -ENOENT: 65531143d5dSDavid Howells case -ENOMEDIUM: 65631143d5dSDavid Howells case -ENXIO: 657f51375cdSDavid Howells trace_afs_file_error(vnode, ret, afs_file_error_writeback_fail); 6584343d008SDavid Howells afs_kill_pages(mapping, first, last); 6594343d008SDavid Howells mapping_set_error(mapping, ret); 66031143d5dSDavid Howells break; 66131143d5dSDavid Howells } 66231143d5dSDavid Howells 66331143d5dSDavid Howells _leave(" = %d", ret); 66431143d5dSDavid Howells return ret; 66531143d5dSDavid Howells } 66631143d5dSDavid Howells 66731143d5dSDavid Howells /* 66831143d5dSDavid Howells * write a page back to the server 66931143d5dSDavid Howells * - the caller locked the page for us 67031143d5dSDavid Howells */ 67131143d5dSDavid Howells int afs_writepage(struct page *page, struct writeback_control *wbc) 67231143d5dSDavid Howells { 67331143d5dSDavid Howells int ret; 67431143d5dSDavid Howells 67531143d5dSDavid Howells _enter("{%lx},", page->index); 67631143d5dSDavid Howells 6774343d008SDavid Howells ret = afs_write_back_from_locked_page(page->mapping, wbc, page, 6784343d008SDavid Howells wbc->range_end >> PAGE_SHIFT); 67931143d5dSDavid Howells if (ret < 0) { 68031143d5dSDavid Howells _leave(" = %d", ret); 68131143d5dSDavid Howells return 0; 68231143d5dSDavid Howells } 68331143d5dSDavid Howells 68431143d5dSDavid Howells wbc->nr_to_write -= ret; 68531143d5dSDavid Howells 68631143d5dSDavid Howells _leave(" = 0"); 68731143d5dSDavid Howells return 0; 68831143d5dSDavid Howells } 68931143d5dSDavid Howells 69031143d5dSDavid Howells /* 69131143d5dSDavid Howells * write a region of pages back to the server 69231143d5dSDavid Howells */ 693c1206a2cSAdrian Bunk static int afs_writepages_region(struct address_space *mapping, 69431143d5dSDavid Howells struct writeback_control *wbc, 69531143d5dSDavid Howells pgoff_t index, pgoff_t end, pgoff_t *_next) 69631143d5dSDavid Howells { 69731143d5dSDavid Howells struct page *page; 69831143d5dSDavid Howells int ret, n; 69931143d5dSDavid Howells 70031143d5dSDavid Howells _enter(",,%lx,%lx,", index, end); 70131143d5dSDavid Howells 70231143d5dSDavid Howells do { 703aef6e415SJan Kara n = find_get_pages_range_tag(mapping, &index, end, 704aef6e415SJan Kara PAGECACHE_TAG_DIRTY, 1, &page); 70531143d5dSDavid Howells if (!n) 70631143d5dSDavid Howells break; 70731143d5dSDavid Howells 70831143d5dSDavid Howells _debug("wback %lx", page->index); 70931143d5dSDavid Howells 710b93b0163SMatthew Wilcox /* 711b93b0163SMatthew Wilcox * at this point we hold neither the i_pages lock nor the 712b93b0163SMatthew Wilcox * page lock: the page may be truncated or invalidated 713b93b0163SMatthew Wilcox * (changing page->mapping to NULL), or even swizzled 714b93b0163SMatthew Wilcox * back from swapper_space to tmpfs file mapping 71531143d5dSDavid Howells */ 7164343d008SDavid Howells ret = lock_page_killable(page); 7174343d008SDavid Howells if (ret < 0) { 7184343d008SDavid Howells put_page(page); 7194343d008SDavid Howells _leave(" = %d", ret); 7204343d008SDavid Howells return ret; 7214343d008SDavid Howells } 72231143d5dSDavid Howells 723c5051c7bSDavid Howells if (page->mapping != mapping || !PageDirty(page)) { 72431143d5dSDavid Howells unlock_page(page); 72509cbfeafSKirill A. Shutemov put_page(page); 72631143d5dSDavid Howells continue; 72731143d5dSDavid Howells } 72831143d5dSDavid Howells 729c5051c7bSDavid Howells if (PageWriteback(page)) { 730c5051c7bSDavid Howells unlock_page(page); 73131143d5dSDavid Howells if (wbc->sync_mode != WB_SYNC_NONE) 73231143d5dSDavid Howells wait_on_page_writeback(page); 73329c8bbbdSDavid Howells put_page(page); 73431143d5dSDavid Howells continue; 73531143d5dSDavid Howells } 73631143d5dSDavid Howells 73765a15109SDavid Howells if (!clear_page_dirty_for_io(page)) 73865a15109SDavid Howells BUG(); 7394343d008SDavid Howells ret = afs_write_back_from_locked_page(mapping, wbc, page, end); 74009cbfeafSKirill A. Shutemov put_page(page); 74131143d5dSDavid Howells if (ret < 0) { 74231143d5dSDavid Howells _leave(" = %d", ret); 74331143d5dSDavid Howells return ret; 74431143d5dSDavid Howells } 74531143d5dSDavid Howells 74631143d5dSDavid Howells wbc->nr_to_write -= ret; 74731143d5dSDavid Howells 74831143d5dSDavid Howells cond_resched(); 74931143d5dSDavid Howells } while (index < end && wbc->nr_to_write > 0); 75031143d5dSDavid Howells 75131143d5dSDavid Howells *_next = index; 75231143d5dSDavid Howells _leave(" = 0 [%lx]", *_next); 75331143d5dSDavid Howells return 0; 75431143d5dSDavid Howells } 75531143d5dSDavid Howells 75631143d5dSDavid Howells /* 75731143d5dSDavid Howells * write some of the pending data back to the server 75831143d5dSDavid Howells */ 75931143d5dSDavid Howells int afs_writepages(struct address_space *mapping, 76031143d5dSDavid Howells struct writeback_control *wbc) 76131143d5dSDavid Howells { 762ec0fa0b6SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 76331143d5dSDavid Howells pgoff_t start, end, next; 76431143d5dSDavid Howells int ret; 76531143d5dSDavid Howells 76631143d5dSDavid Howells _enter(""); 76731143d5dSDavid Howells 768ec0fa0b6SDavid Howells /* We have to be careful as we can end up racing with setattr() 769ec0fa0b6SDavid Howells * truncating the pagecache since the caller doesn't take a lock here 770ec0fa0b6SDavid Howells * to prevent it. 771ec0fa0b6SDavid Howells */ 772ec0fa0b6SDavid Howells if (wbc->sync_mode == WB_SYNC_ALL) 773ec0fa0b6SDavid Howells down_read(&vnode->validate_lock); 774ec0fa0b6SDavid Howells else if (!down_read_trylock(&vnode->validate_lock)) 775ec0fa0b6SDavid Howells return 0; 776ec0fa0b6SDavid Howells 77731143d5dSDavid Howells if (wbc->range_cyclic) { 77831143d5dSDavid Howells start = mapping->writeback_index; 77931143d5dSDavid Howells end = -1; 78031143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, start, end, &next); 7811b430beeSWu Fengguang if (start > 0 && wbc->nr_to_write > 0 && ret == 0) 78231143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, 0, start, 78331143d5dSDavid Howells &next); 78431143d5dSDavid Howells mapping->writeback_index = next; 78531143d5dSDavid Howells } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) { 78609cbfeafSKirill A. Shutemov end = (pgoff_t)(LLONG_MAX >> PAGE_SHIFT); 78731143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, 0, end, &next); 78831143d5dSDavid Howells if (wbc->nr_to_write > 0) 78931143d5dSDavid Howells mapping->writeback_index = next; 79031143d5dSDavid Howells } else { 79109cbfeafSKirill A. Shutemov start = wbc->range_start >> PAGE_SHIFT; 79209cbfeafSKirill A. Shutemov end = wbc->range_end >> PAGE_SHIFT; 79331143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, start, end, &next); 79431143d5dSDavid Howells } 79531143d5dSDavid Howells 796ec0fa0b6SDavid Howells up_read(&vnode->validate_lock); 79731143d5dSDavid Howells _leave(" = %d", ret); 79831143d5dSDavid Howells return ret; 79931143d5dSDavid Howells } 80031143d5dSDavid Howells 80131143d5dSDavid Howells /* 80231143d5dSDavid Howells * write to an AFS file 80331143d5dSDavid Howells */ 80450b5551dSAl Viro ssize_t afs_file_write(struct kiocb *iocb, struct iov_iter *from) 80531143d5dSDavid Howells { 806496ad9aaSAl Viro struct afs_vnode *vnode = AFS_FS_I(file_inode(iocb->ki_filp)); 80731143d5dSDavid Howells ssize_t result; 80850b5551dSAl Viro size_t count = iov_iter_count(from); 80931143d5dSDavid Howells 8103b6492dfSDavid Howells _enter("{%llx:%llu},{%zu},", 81150b5551dSAl Viro vnode->fid.vid, vnode->fid.vnode, count); 81231143d5dSDavid Howells 81331143d5dSDavid Howells if (IS_SWAPFILE(&vnode->vfs_inode)) { 81431143d5dSDavid Howells printk(KERN_INFO 81531143d5dSDavid Howells "AFS: Attempt to write to active swap file!\n"); 81631143d5dSDavid Howells return -EBUSY; 81731143d5dSDavid Howells } 81831143d5dSDavid Howells 81931143d5dSDavid Howells if (!count) 82031143d5dSDavid Howells return 0; 82131143d5dSDavid Howells 82250b5551dSAl Viro result = generic_file_write_iter(iocb, from); 82331143d5dSDavid Howells 82431143d5dSDavid Howells _leave(" = %zd", result); 82531143d5dSDavid Howells return result; 82631143d5dSDavid Howells } 82731143d5dSDavid Howells 82831143d5dSDavid Howells /* 82931143d5dSDavid Howells * flush any dirty pages for this process, and check for write errors. 83031143d5dSDavid Howells * - the return status from this call provides a reliable indication of 83131143d5dSDavid Howells * whether any write errors occurred for this process. 83231143d5dSDavid Howells */ 83302c24a82SJosef Bacik int afs_fsync(struct file *file, loff_t start, loff_t end, int datasync) 83431143d5dSDavid Howells { 8353c981bfcSAl Viro struct inode *inode = file_inode(file); 8363c981bfcSAl Viro struct afs_vnode *vnode = AFS_FS_I(inode); 83731143d5dSDavid Howells 8383b6492dfSDavid Howells _enter("{%llx:%llu},{n=%pD},%d", 8393c981bfcSAl Viro vnode->fid.vid, vnode->fid.vnode, file, 84031143d5dSDavid Howells datasync); 84131143d5dSDavid Howells 8424343d008SDavid Howells return file_write_and_wait_range(file, start, end); 84331143d5dSDavid Howells } 8449b3f26c9SDavid Howells 8459b3f26c9SDavid Howells /* 8469b3f26c9SDavid Howells * notification that a previously read-only page is about to become writable 8479b3f26c9SDavid Howells * - if it returns an error, the caller will deliver a bus error signal 8489b3f26c9SDavid Howells */ 8490722f186SSouptick Joarder vm_fault_t afs_page_mkwrite(struct vm_fault *vmf) 8509b3f26c9SDavid Howells { 8511cf7a151SDavid Howells struct file *file = vmf->vma->vm_file; 8521cf7a151SDavid Howells struct inode *inode = file_inode(file); 8531cf7a151SDavid Howells struct afs_vnode *vnode = AFS_FS_I(inode); 8541cf7a151SDavid Howells unsigned long priv; 8559b3f26c9SDavid Howells 8563b6492dfSDavid Howells _enter("{{%llx:%llu}},{%lx}", 8571cf7a151SDavid Howells vnode->fid.vid, vnode->fid.vnode, vmf->page->index); 8589b3f26c9SDavid Howells 8591cf7a151SDavid Howells sb_start_pagefault(inode->i_sb); 8601cf7a151SDavid Howells 8611cf7a151SDavid Howells /* Wait for the page to be written to the cache before we allow it to 8621cf7a151SDavid Howells * be modified. We then assume the entire page will need writing back. 8631cf7a151SDavid Howells */ 864*630f5ddaSDavid Howells #ifdef CONFIG_AFS_FSCACHE 865*630f5ddaSDavid Howells if (PageFsCache(vmf->page) && 866*630f5ddaSDavid Howells wait_on_page_bit_killable(vmf->page, PG_fscache) < 0) 867*630f5ddaSDavid Howells return VM_FAULT_RETRY; 868*630f5ddaSDavid Howells #endif 8699b3f26c9SDavid Howells 87075b69799SMatthew Wilcox (Oracle) if (wait_on_page_writeback_killable(vmf->page)) 8711cf7a151SDavid Howells return VM_FAULT_RETRY; 8721cf7a151SDavid Howells 8731cf7a151SDavid Howells if (lock_page_killable(vmf->page) < 0) 8741cf7a151SDavid Howells return VM_FAULT_RETRY; 8751cf7a151SDavid Howells 8761cf7a151SDavid Howells /* We mustn't change page->private until writeback is complete as that 8771cf7a151SDavid Howells * details the portion of the page we need to write back and we might 8781cf7a151SDavid Howells * need to redirty the page if there's a problem. 8791cf7a151SDavid Howells */ 8801cf7a151SDavid Howells wait_on_page_writeback(vmf->page); 8811cf7a151SDavid Howells 88267d78a6fSDavid Howells priv = afs_page_dirty(vmf->page, 0, PAGE_SIZE); 883f86726a6SDavid Howells priv = afs_page_dirty_mmapped(priv); 884fa04a40bSDavid Howells if (PagePrivate(vmf->page)) 8851cf7a151SDavid Howells set_page_private(vmf->page, priv); 886fa04a40bSDavid Howells else 887fa04a40bSDavid Howells attach_page_private(vmf->page, (void *)priv); 88867d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("mkwrite"), vmf->page); 889bb413489SDavid Howells file_update_time(file); 8901cf7a151SDavid Howells 8911cf7a151SDavid Howells sb_end_pagefault(inode->i_sb); 8921cf7a151SDavid Howells return VM_FAULT_LOCKED; 8939b3f26c9SDavid Howells } 8944343d008SDavid Howells 8954343d008SDavid Howells /* 8964343d008SDavid Howells * Prune the keys cached for writeback. The caller must hold vnode->wb_lock. 8974343d008SDavid Howells */ 8984343d008SDavid Howells void afs_prune_wb_keys(struct afs_vnode *vnode) 8994343d008SDavid Howells { 9004343d008SDavid Howells LIST_HEAD(graveyard); 9014343d008SDavid Howells struct afs_wb_key *wbk, *tmp; 9024343d008SDavid Howells 9034343d008SDavid Howells /* Discard unused keys */ 9044343d008SDavid Howells spin_lock(&vnode->wb_lock); 9054343d008SDavid Howells 9064343d008SDavid Howells if (!mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_WRITEBACK) && 9074343d008SDavid Howells !mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_DIRTY)) { 9084343d008SDavid Howells list_for_each_entry_safe(wbk, tmp, &vnode->wb_keys, vnode_link) { 9094343d008SDavid Howells if (refcount_read(&wbk->usage) == 1) 9104343d008SDavid Howells list_move(&wbk->vnode_link, &graveyard); 9114343d008SDavid Howells } 9124343d008SDavid Howells } 9134343d008SDavid Howells 9144343d008SDavid Howells spin_unlock(&vnode->wb_lock); 9154343d008SDavid Howells 9164343d008SDavid Howells while (!list_empty(&graveyard)) { 9174343d008SDavid Howells wbk = list_entry(graveyard.next, struct afs_wb_key, vnode_link); 9184343d008SDavid Howells list_del(&wbk->vnode_link); 9194343d008SDavid Howells afs_put_wb_key(wbk); 9204343d008SDavid Howells } 9214343d008SDavid Howells } 9224343d008SDavid Howells 9234343d008SDavid Howells /* 9244343d008SDavid Howells * Clean up a page during invalidation. 9254343d008SDavid Howells */ 9264343d008SDavid Howells int afs_launder_page(struct page *page) 9274343d008SDavid Howells { 9284343d008SDavid Howells struct address_space *mapping = page->mapping; 9294343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 930bd80d8a8SDavid Howells struct iov_iter iter; 931bd80d8a8SDavid Howells struct bio_vec bv[1]; 9324343d008SDavid Howells unsigned long priv; 9334343d008SDavid Howells unsigned int f, t; 9344343d008SDavid Howells int ret = 0; 9354343d008SDavid Howells 9364343d008SDavid Howells _enter("{%lx}", page->index); 9374343d008SDavid Howells 9384343d008SDavid Howells priv = page_private(page); 9394343d008SDavid Howells if (clear_page_dirty_for_io(page)) { 9404343d008SDavid Howells f = 0; 9414343d008SDavid Howells t = PAGE_SIZE; 9424343d008SDavid Howells if (PagePrivate(page)) { 94367d78a6fSDavid Howells f = afs_page_dirty_from(page, priv); 94467d78a6fSDavid Howells t = afs_page_dirty_to(page, priv); 9454343d008SDavid Howells } 9464343d008SDavid Howells 947bd80d8a8SDavid Howells bv[0].bv_page = page; 948bd80d8a8SDavid Howells bv[0].bv_offset = f; 949bd80d8a8SDavid Howells bv[0].bv_len = t - f; 950bd80d8a8SDavid Howells iov_iter_bvec(&iter, WRITE, bv, 1, bv[0].bv_len); 951bd80d8a8SDavid Howells 95267d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("launder"), page); 953bd80d8a8SDavid Howells ret = afs_store_data(vnode, &iter, (loff_t)page->index << PAGE_SHIFT, 954bd80d8a8SDavid Howells page->index, page->index, true); 9554343d008SDavid Howells } 9564343d008SDavid Howells 95767d78a6fSDavid Howells detach_page_private(page); 95867d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("laundered"), page); 959*630f5ddaSDavid Howells wait_on_page_fscache(page); 9604343d008SDavid Howells return ret; 96131143d5dSDavid Howells } 962