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 */ 28*c69bf479SDavid Howells static int afs_fill_page(struct file *file, 29e8e581a8SDavid Howells loff_t pos, unsigned int len, struct page *page) 3031143d5dSDavid Howells { 31*c69bf479SDavid Howells struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); 32196ee9cdSDavid Howells struct afs_read *req; 332a0b4f64SDavid Howells size_t p; 342a0b4f64SDavid Howells void *data; 3531143d5dSDavid Howells int ret; 3631143d5dSDavid Howells 375e7f2337SAnton Blanchard _enter(",,%llu", (unsigned long long)pos); 3831143d5dSDavid Howells 392a0b4f64SDavid Howells if (pos >= vnode->vfs_inode.i_size) { 402a0b4f64SDavid Howells p = pos & ~PAGE_MASK; 412a0b4f64SDavid Howells ASSERTCMP(p + len, <=, PAGE_SIZE); 422a0b4f64SDavid Howells data = kmap(page); 432a0b4f64SDavid Howells memset(data + p, 0, len); 442a0b4f64SDavid Howells kunmap(page); 452a0b4f64SDavid Howells return 0; 462a0b4f64SDavid Howells } 472a0b4f64SDavid Howells 48ee102584SZhengyuan Liu req = kzalloc(struct_size(req, array, 1), GFP_KERNEL); 49196ee9cdSDavid Howells if (!req) 50196ee9cdSDavid Howells return -ENOMEM; 51196ee9cdSDavid Howells 52f3ddee8dSDavid Howells refcount_set(&req->usage, 1); 53*c69bf479SDavid Howells req->key = key_get(afs_file_key(file)); 54196ee9cdSDavid Howells req->pos = pos; 55e8e581a8SDavid Howells req->len = len; 56196ee9cdSDavid Howells req->nr_pages = 1; 57f3ddee8dSDavid Howells req->pages = req->array; 58196ee9cdSDavid Howells req->pages[0] = page; 595611ef28SDavid Howells get_page(page); 60196ee9cdSDavid Howells 61*c69bf479SDavid Howells ret = afs_fetch_data(vnode, req); 62196ee9cdSDavid Howells afs_put_read(req); 6331143d5dSDavid Howells if (ret < 0) { 6431143d5dSDavid Howells if (ret == -ENOENT) { 6531143d5dSDavid Howells _debug("got NOENT from server" 6631143d5dSDavid Howells " - marking file deleted and stale"); 6731143d5dSDavid Howells set_bit(AFS_VNODE_DELETED, &vnode->flags); 6831143d5dSDavid Howells ret = -ESTALE; 6931143d5dSDavid Howells } 7031143d5dSDavid Howells } 7131143d5dSDavid Howells 7231143d5dSDavid Howells _leave(" = %d", ret); 7331143d5dSDavid Howells return ret; 7431143d5dSDavid Howells } 7531143d5dSDavid Howells 7631143d5dSDavid Howells /* 7731143d5dSDavid Howells * prepare to perform part of a write to a page 7831143d5dSDavid Howells */ 7915b4650eSNick Piggin int afs_write_begin(struct file *file, struct address_space *mapping, 8015b4650eSNick Piggin loff_t pos, unsigned len, unsigned flags, 8121db2cdcSDavid Howells struct page **_page, void **fsdata) 8231143d5dSDavid Howells { 83496ad9aaSAl Viro struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); 8415b4650eSNick Piggin struct page *page; 854343d008SDavid Howells unsigned long priv; 864343d008SDavid Howells unsigned f, from = pos & (PAGE_SIZE - 1); 874343d008SDavid Howells unsigned t, to = from + len; 8809cbfeafSKirill A. Shutemov pgoff_t index = pos >> PAGE_SHIFT; 8931143d5dSDavid Howells int ret; 9031143d5dSDavid Howells 913b6492dfSDavid Howells _enter("{%llx:%llu},{%lx},%u,%u", 9215b4650eSNick Piggin vnode->fid.vid, vnode->fid.vnode, index, from, to); 9331143d5dSDavid Howells 9454566b2cSNick Piggin page = grab_cache_page_write_begin(mapping, index, flags); 954343d008SDavid Howells if (!page) 9615b4650eSNick Piggin return -ENOMEM; 9715b4650eSNick Piggin 9809cbfeafSKirill A. Shutemov if (!PageUptodate(page) && len != PAGE_SIZE) { 99*c69bf479SDavid Howells ret = afs_fill_page(file, pos & PAGE_MASK, PAGE_SIZE, page); 10031143d5dSDavid Howells if (ret < 0) { 1016d06b0d2SDavid Howells unlock_page(page); 1026d06b0d2SDavid Howells put_page(page); 10331143d5dSDavid Howells _leave(" = %d [prep]", ret); 10431143d5dSDavid Howells return ret; 10531143d5dSDavid Howells } 10615b4650eSNick Piggin SetPageUptodate(page); 10731143d5dSDavid Howells } 10831143d5dSDavid Howells 10931143d5dSDavid Howells try_again: 1104343d008SDavid Howells /* See if this page is already partially written in a way that we can 1114343d008SDavid Howells * merge the new write with. 1124343d008SDavid Howells */ 1134343d008SDavid Howells t = f = 0; 1144343d008SDavid Howells if (PagePrivate(page)) { 1154343d008SDavid Howells priv = page_private(page); 11667d78a6fSDavid Howells f = afs_page_dirty_from(page, priv); 11767d78a6fSDavid Howells t = afs_page_dirty_to(page, priv); 1184343d008SDavid Howells ASSERTCMP(f, <=, t); 11931143d5dSDavid Howells } 12031143d5dSDavid Howells 1214343d008SDavid Howells if (f != t) { 1225a039c32SDavid Howells if (PageWriteback(page)) { 12367d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("alrdy"), page); 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)); 167f792e3acSDavid Howells unsigned long priv; 168f792e3acSDavid Howells unsigned int f, from = pos & (PAGE_SIZE - 1); 169f792e3acSDavid Howells unsigned int t, to = from + copied; 17031143d5dSDavid Howells loff_t i_size, maybe_i_size; 1713ad216eeSDavid Howells int ret = 0; 17231143d5dSDavid Howells 1733b6492dfSDavid Howells _enter("{%llx:%llu},{%lx}", 17415b4650eSNick Piggin vnode->fid.vid, vnode->fid.vnode, page->index); 17531143d5dSDavid Howells 1763ad216eeSDavid Howells if (copied == 0) 1773ad216eeSDavid Howells goto out; 1783ad216eeSDavid Howells 17915b4650eSNick Piggin maybe_i_size = pos + copied; 18031143d5dSDavid Howells 18131143d5dSDavid Howells i_size = i_size_read(&vnode->vfs_inode); 18231143d5dSDavid Howells if (maybe_i_size > i_size) { 1831f32ef79SDavid Howells write_seqlock(&vnode->cb_lock); 18431143d5dSDavid Howells i_size = i_size_read(&vnode->vfs_inode); 18531143d5dSDavid Howells if (maybe_i_size > i_size) 18631143d5dSDavid Howells i_size_write(&vnode->vfs_inode, maybe_i_size); 1871f32ef79SDavid Howells write_sequnlock(&vnode->cb_lock); 18831143d5dSDavid Howells } 18931143d5dSDavid Howells 190e8e581a8SDavid Howells if (!PageUptodate(page)) { 191e8e581a8SDavid Howells if (copied < len) { 192e8e581a8SDavid Howells /* Try and load any missing data from the server. The 193e8e581a8SDavid Howells * unmarshalling routine will take care of clearing any 194e8e581a8SDavid Howells * bits that are beyond the EOF. 195e8e581a8SDavid Howells */ 196*c69bf479SDavid Howells ret = afs_fill_page(file, pos + copied, 197e8e581a8SDavid Howells len - copied, page); 198e8e581a8SDavid Howells if (ret < 0) 199afae457dSDavid Howells goto out; 200e8e581a8SDavid Howells } 201e8e581a8SDavid Howells SetPageUptodate(page); 202e8e581a8SDavid Howells } 203e8e581a8SDavid Howells 204f792e3acSDavid Howells if (PagePrivate(page)) { 205f792e3acSDavid Howells priv = page_private(page); 20667d78a6fSDavid Howells f = afs_page_dirty_from(page, priv); 20767d78a6fSDavid Howells t = afs_page_dirty_to(page, priv); 208f792e3acSDavid Howells if (from < f) 209f792e3acSDavid Howells f = from; 210f792e3acSDavid Howells if (to > t) 211f792e3acSDavid Howells t = to; 21267d78a6fSDavid Howells priv = afs_page_dirty(page, f, t); 213f792e3acSDavid Howells set_page_private(page, priv); 21467d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("dirty+"), page); 215f792e3acSDavid Howells } else { 21667d78a6fSDavid Howells priv = afs_page_dirty(page, from, to); 217f792e3acSDavid Howells attach_page_private(page, (void *)priv); 21867d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("dirty"), page); 219f792e3acSDavid Howells } 220f792e3acSDavid Howells 22131143d5dSDavid Howells set_page_dirty(page); 22231143d5dSDavid Howells if (PageDirty(page)) 22331143d5dSDavid Howells _debug("dirtied"); 224afae457dSDavid Howells ret = copied; 225afae457dSDavid Howells 226afae457dSDavid Howells out: 22715b4650eSNick Piggin unlock_page(page); 22809cbfeafSKirill A. Shutemov put_page(page); 229afae457dSDavid Howells return ret; 23031143d5dSDavid Howells } 23131143d5dSDavid Howells 23231143d5dSDavid Howells /* 23331143d5dSDavid Howells * kill all the pages in the given range 23431143d5dSDavid Howells */ 2354343d008SDavid Howells static void afs_kill_pages(struct address_space *mapping, 23631143d5dSDavid Howells pgoff_t first, pgoff_t last) 23731143d5dSDavid Howells { 2384343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 23931143d5dSDavid Howells struct pagevec pv; 24031143d5dSDavid Howells unsigned count, loop; 24131143d5dSDavid Howells 2423b6492dfSDavid Howells _enter("{%llx:%llu},%lx-%lx", 24331143d5dSDavid Howells vnode->fid.vid, vnode->fid.vnode, first, last); 24431143d5dSDavid Howells 24586679820SMel Gorman pagevec_init(&pv); 24631143d5dSDavid Howells 24731143d5dSDavid Howells do { 24831143d5dSDavid Howells _debug("kill %lx-%lx", first, last); 24931143d5dSDavid Howells 25031143d5dSDavid Howells count = last - first + 1; 25131143d5dSDavid Howells if (count > PAGEVEC_SIZE) 25231143d5dSDavid Howells count = PAGEVEC_SIZE; 2534343d008SDavid Howells pv.nr = find_get_pages_contig(mapping, first, count, pv.pages); 25431143d5dSDavid Howells ASSERTCMP(pv.nr, ==, count); 25531143d5dSDavid Howells 25631143d5dSDavid Howells for (loop = 0; loop < count; loop++) { 2577286a35eSDavid Howells struct page *page = pv.pages[loop]; 2587286a35eSDavid Howells ClearPageUptodate(page); 2597286a35eSDavid Howells SetPageError(page); 2604343d008SDavid Howells end_page_writeback(page); 2614343d008SDavid Howells if (page->index >= first) 2624343d008SDavid Howells first = page->index + 1; 2634343d008SDavid Howells lock_page(page); 2644343d008SDavid Howells generic_error_remove_page(mapping, page); 26521bd68f1SMarc Dionne unlock_page(page); 2664343d008SDavid Howells } 2674343d008SDavid Howells 2684343d008SDavid Howells __pagevec_release(&pv); 2694343d008SDavid Howells } while (first <= last); 2704343d008SDavid Howells 2714343d008SDavid Howells _leave(""); 2724343d008SDavid Howells } 2734343d008SDavid Howells 2744343d008SDavid Howells /* 2754343d008SDavid Howells * Redirty all the pages in a given range. 2764343d008SDavid Howells */ 2774343d008SDavid Howells static void afs_redirty_pages(struct writeback_control *wbc, 2784343d008SDavid Howells struct address_space *mapping, 2794343d008SDavid Howells pgoff_t first, pgoff_t last) 2804343d008SDavid Howells { 2814343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 2824343d008SDavid Howells struct pagevec pv; 2834343d008SDavid Howells unsigned count, loop; 2844343d008SDavid Howells 2853b6492dfSDavid Howells _enter("{%llx:%llu},%lx-%lx", 2864343d008SDavid Howells vnode->fid.vid, vnode->fid.vnode, first, last); 2874343d008SDavid Howells 288487e2c9fSLinus Torvalds pagevec_init(&pv); 2894343d008SDavid Howells 2904343d008SDavid Howells do { 2914343d008SDavid Howells _debug("redirty %lx-%lx", first, last); 2924343d008SDavid Howells 2934343d008SDavid Howells count = last - first + 1; 2944343d008SDavid Howells if (count > PAGEVEC_SIZE) 2954343d008SDavid Howells count = PAGEVEC_SIZE; 2964343d008SDavid Howells pv.nr = find_get_pages_contig(mapping, first, count, pv.pages); 2974343d008SDavid Howells ASSERTCMP(pv.nr, ==, count); 2984343d008SDavid Howells 2994343d008SDavid Howells for (loop = 0; loop < count; loop++) { 3004343d008SDavid Howells struct page *page = pv.pages[loop]; 3014343d008SDavid Howells 3024343d008SDavid Howells redirty_page_for_writepage(wbc, page); 3037286a35eSDavid Howells end_page_writeback(page); 3047286a35eSDavid Howells if (page->index >= first) 3057286a35eSDavid Howells first = page->index + 1; 30631143d5dSDavid Howells } 30731143d5dSDavid Howells 30831143d5dSDavid Howells __pagevec_release(&pv); 3094343d008SDavid Howells } while (first <= last); 31031143d5dSDavid Howells 31131143d5dSDavid Howells _leave(""); 31231143d5dSDavid Howells } 31331143d5dSDavid Howells 31431143d5dSDavid Howells /* 315a58823acSDavid Howells * completion of write to server 316a58823acSDavid Howells */ 317a58823acSDavid Howells static void afs_pages_written_back(struct afs_vnode *vnode, 318a58823acSDavid Howells pgoff_t first, pgoff_t last) 319a58823acSDavid Howells { 320a58823acSDavid Howells struct pagevec pv; 321a58823acSDavid Howells unsigned count, loop; 322a58823acSDavid Howells 323a58823acSDavid Howells _enter("{%llx:%llu},{%lx-%lx}", 324a58823acSDavid Howells vnode->fid.vid, vnode->fid.vnode, first, last); 325a58823acSDavid Howells 326a58823acSDavid Howells pagevec_init(&pv); 327a58823acSDavid Howells 328a58823acSDavid Howells do { 329a58823acSDavid Howells _debug("done %lx-%lx", first, last); 330a58823acSDavid Howells 331a58823acSDavid Howells count = last - first + 1; 332a58823acSDavid Howells if (count > PAGEVEC_SIZE) 333a58823acSDavid Howells count = PAGEVEC_SIZE; 334a58823acSDavid Howells pv.nr = find_get_pages_contig(vnode->vfs_inode.i_mapping, 335a58823acSDavid Howells first, count, pv.pages); 336a58823acSDavid Howells ASSERTCMP(pv.nr, ==, count); 337a58823acSDavid Howells 338a58823acSDavid Howells for (loop = 0; loop < count; loop++) { 33967d78a6fSDavid Howells detach_page_private(pv.pages[loop]); 340a58823acSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("clear"), 34167d78a6fSDavid Howells pv.pages[loop]); 342a58823acSDavid Howells end_page_writeback(pv.pages[loop]); 343a58823acSDavid Howells } 344a58823acSDavid Howells first += count; 345a58823acSDavid Howells __pagevec_release(&pv); 346a58823acSDavid Howells } while (first <= last); 347a58823acSDavid Howells 348a58823acSDavid Howells afs_prune_wb_keys(vnode); 349a58823acSDavid Howells _leave(""); 350a58823acSDavid Howells } 351a58823acSDavid Howells 352a58823acSDavid Howells /* 353e49c7b2fSDavid Howells * Find a key to use for the writeback. We cached the keys used to author the 354e49c7b2fSDavid Howells * writes on the vnode. *_wbk will contain the last writeback key used or NULL 355e49c7b2fSDavid Howells * and we need to start from there if it's set. 356e49c7b2fSDavid Howells */ 357e49c7b2fSDavid Howells static int afs_get_writeback_key(struct afs_vnode *vnode, 358e49c7b2fSDavid Howells struct afs_wb_key **_wbk) 359e49c7b2fSDavid Howells { 360e49c7b2fSDavid Howells struct afs_wb_key *wbk = NULL; 361e49c7b2fSDavid Howells struct list_head *p; 362e49c7b2fSDavid Howells int ret = -ENOKEY, ret2; 363e49c7b2fSDavid Howells 364e49c7b2fSDavid Howells spin_lock(&vnode->wb_lock); 365e49c7b2fSDavid Howells if (*_wbk) 366e49c7b2fSDavid Howells p = (*_wbk)->vnode_link.next; 367e49c7b2fSDavid Howells else 368e49c7b2fSDavid Howells p = vnode->wb_keys.next; 369e49c7b2fSDavid Howells 370e49c7b2fSDavid Howells while (p != &vnode->wb_keys) { 371e49c7b2fSDavid Howells wbk = list_entry(p, struct afs_wb_key, vnode_link); 372e49c7b2fSDavid Howells _debug("wbk %u", key_serial(wbk->key)); 373e49c7b2fSDavid Howells ret2 = key_validate(wbk->key); 374e49c7b2fSDavid Howells if (ret2 == 0) { 375e49c7b2fSDavid Howells refcount_inc(&wbk->usage); 376e49c7b2fSDavid Howells _debug("USE WB KEY %u", key_serial(wbk->key)); 377e49c7b2fSDavid Howells break; 378e49c7b2fSDavid Howells } 379e49c7b2fSDavid Howells 380e49c7b2fSDavid Howells wbk = NULL; 381e49c7b2fSDavid Howells if (ret == -ENOKEY) 382e49c7b2fSDavid Howells ret = ret2; 383e49c7b2fSDavid Howells p = p->next; 384e49c7b2fSDavid Howells } 385e49c7b2fSDavid Howells 386e49c7b2fSDavid Howells spin_unlock(&vnode->wb_lock); 387e49c7b2fSDavid Howells if (*_wbk) 388e49c7b2fSDavid Howells afs_put_wb_key(*_wbk); 389e49c7b2fSDavid Howells *_wbk = wbk; 390e49c7b2fSDavid Howells return 0; 391e49c7b2fSDavid Howells } 392e49c7b2fSDavid Howells 393e49c7b2fSDavid Howells static void afs_store_data_success(struct afs_operation *op) 394e49c7b2fSDavid Howells { 395e49c7b2fSDavid Howells struct afs_vnode *vnode = op->file[0].vnode; 396e49c7b2fSDavid Howells 397da8d0755SDavid Howells op->ctime = op->file[0].scb.status.mtime_client; 398e49c7b2fSDavid Howells afs_vnode_commit_status(op, &op->file[0]); 399e49c7b2fSDavid Howells if (op->error == 0) { 400d383e346SDavid Howells if (!op->store.laundering) 401e49c7b2fSDavid Howells afs_pages_written_back(vnode, op->store.first, op->store.last); 402e49c7b2fSDavid Howells afs_stat_v(vnode, n_stores); 403e49c7b2fSDavid Howells atomic_long_add((op->store.last * PAGE_SIZE + op->store.last_to) - 404e49c7b2fSDavid Howells (op->store.first * PAGE_SIZE + op->store.first_offset), 405e49c7b2fSDavid Howells &afs_v2net(vnode)->n_store_bytes); 406e49c7b2fSDavid Howells } 407e49c7b2fSDavid Howells } 408e49c7b2fSDavid Howells 409e49c7b2fSDavid Howells static const struct afs_operation_ops afs_store_data_operation = { 410e49c7b2fSDavid Howells .issue_afs_rpc = afs_fs_store_data, 411e49c7b2fSDavid Howells .issue_yfs_rpc = yfs_fs_store_data, 412e49c7b2fSDavid Howells .success = afs_store_data_success, 413e49c7b2fSDavid Howells }; 414e49c7b2fSDavid Howells 415e49c7b2fSDavid Howells /* 416d2ddc776SDavid Howells * write to a file 41731143d5dSDavid Howells */ 4184343d008SDavid Howells static int afs_store_data(struct address_space *mapping, 4194343d008SDavid Howells pgoff_t first, pgoff_t last, 420d383e346SDavid Howells unsigned offset, unsigned to, bool laundering) 42131143d5dSDavid Howells { 4224343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 423e49c7b2fSDavid Howells struct afs_operation *op; 4244343d008SDavid Howells struct afs_wb_key *wbk = NULL; 425e49c7b2fSDavid Howells int ret; 426d2ddc776SDavid Howells 4273b6492dfSDavid Howells _enter("%s{%llx:%llu.%u},%lx,%lx,%x,%x", 428d2ddc776SDavid Howells vnode->volume->name, 429d2ddc776SDavid Howells vnode->fid.vid, 430d2ddc776SDavid Howells vnode->fid.vnode, 431d2ddc776SDavid Howells vnode->fid.unique, 432d2ddc776SDavid Howells first, last, offset, to); 433d2ddc776SDavid Howells 434e49c7b2fSDavid Howells ret = afs_get_writeback_key(vnode, &wbk); 435e49c7b2fSDavid Howells if (ret) { 4364343d008SDavid Howells _leave(" = %d [no keys]", ret); 4374343d008SDavid Howells return ret; 438d2ddc776SDavid Howells } 439d2ddc776SDavid Howells 440e49c7b2fSDavid Howells op = afs_alloc_operation(wbk->key, vnode->volume); 441e49c7b2fSDavid Howells if (IS_ERR(op)) { 442e49c7b2fSDavid Howells afs_put_wb_key(wbk); 443e49c7b2fSDavid Howells return -ENOMEM; 444d2ddc776SDavid Howells } 445d2ddc776SDavid Howells 446e49c7b2fSDavid Howells afs_op_set_vnode(op, 0, vnode); 447e49c7b2fSDavid Howells op->file[0].dv_delta = 1; 448e49c7b2fSDavid Howells op->store.mapping = mapping; 449e49c7b2fSDavid Howells op->store.first = first; 450e49c7b2fSDavid Howells op->store.last = last; 451e49c7b2fSDavid Howells op->store.first_offset = offset; 452e49c7b2fSDavid Howells op->store.last_to = to; 453d383e346SDavid Howells op->store.laundering = laundering; 454b3597945SDavid Howells op->mtime = vnode->vfs_inode.i_mtime; 455811f04baSDavid Howells op->flags |= AFS_OPERATION_UNINTR; 456e49c7b2fSDavid Howells op->ops = &afs_store_data_operation; 457e49c7b2fSDavid Howells 458e49c7b2fSDavid Howells try_next_key: 459e49c7b2fSDavid Howells afs_begin_vnode_operation(op); 460e49c7b2fSDavid Howells afs_wait_for_operation(op); 461e49c7b2fSDavid Howells 462e49c7b2fSDavid Howells switch (op->error) { 4634343d008SDavid Howells case -EACCES: 4644343d008SDavid Howells case -EPERM: 4654343d008SDavid Howells case -ENOKEY: 4664343d008SDavid Howells case -EKEYEXPIRED: 4674343d008SDavid Howells case -EKEYREJECTED: 4684343d008SDavid Howells case -EKEYREVOKED: 4694343d008SDavid Howells _debug("next"); 470e49c7b2fSDavid Howells 471e49c7b2fSDavid Howells ret = afs_get_writeback_key(vnode, &wbk); 472e49c7b2fSDavid Howells if (ret == 0) { 473e49c7b2fSDavid Howells key_put(op->key); 474e49c7b2fSDavid Howells op->key = key_get(wbk->key); 4754343d008SDavid Howells goto try_next_key; 4764343d008SDavid Howells } 477e49c7b2fSDavid Howells break; 478e49c7b2fSDavid Howells } 4794343d008SDavid Howells 4804343d008SDavid Howells afs_put_wb_key(wbk); 481e49c7b2fSDavid Howells _leave(" = %d", op->error); 482e49c7b2fSDavid Howells return afs_put_operation(op); 483d2ddc776SDavid Howells } 484d2ddc776SDavid Howells 485d2ddc776SDavid Howells /* 4864343d008SDavid Howells * Synchronously write back the locked page and any subsequent non-locked dirty 4874343d008SDavid Howells * pages. 48831143d5dSDavid Howells */ 4894343d008SDavid Howells static int afs_write_back_from_locked_page(struct address_space *mapping, 4904343d008SDavid Howells struct writeback_control *wbc, 4914343d008SDavid Howells struct page *primary_page, 4924343d008SDavid Howells pgoff_t final_page) 49331143d5dSDavid Howells { 49413524ab3SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 49531143d5dSDavid Howells struct page *pages[8], *page; 4964343d008SDavid Howells unsigned long count, priv; 4974343d008SDavid Howells unsigned n, offset, to, f, t; 49831143d5dSDavid Howells pgoff_t start, first, last; 499793fe82eSDavid Howells loff_t i_size, end; 50031143d5dSDavid Howells int loop, ret; 50131143d5dSDavid Howells 50231143d5dSDavid Howells _enter(",%lx", primary_page->index); 50331143d5dSDavid Howells 50431143d5dSDavid Howells count = 1; 50531143d5dSDavid Howells if (test_set_page_writeback(primary_page)) 50631143d5dSDavid Howells BUG(); 50731143d5dSDavid Howells 5084343d008SDavid Howells /* Find all consecutive lockable dirty pages that have contiguous 5094343d008SDavid Howells * written regions, stopping when we find a page that is not 5104343d008SDavid Howells * immediately lockable, is not dirty or is missing, or we reach the 5114343d008SDavid Howells * end of the range. 5124343d008SDavid Howells */ 51331143d5dSDavid Howells start = primary_page->index; 5144343d008SDavid Howells priv = page_private(primary_page); 51567d78a6fSDavid Howells offset = afs_page_dirty_from(primary_page, priv); 51667d78a6fSDavid Howells to = afs_page_dirty_to(primary_page, priv); 51767d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("store"), primary_page); 5184343d008SDavid Howells 5194343d008SDavid Howells WARN_ON(offset == to); 52013524ab3SDavid Howells if (offset == to) 52167d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("WARN"), primary_page); 5224343d008SDavid Howells 5235a813276SDavid Howells if (start >= final_page || 5245a813276SDavid Howells (to < PAGE_SIZE && !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags))) 52531143d5dSDavid Howells goto no_more; 5264343d008SDavid Howells 52731143d5dSDavid Howells start++; 52831143d5dSDavid Howells do { 52931143d5dSDavid Howells _debug("more %lx [%lx]", start, count); 5304343d008SDavid Howells n = final_page - start + 1; 53131143d5dSDavid Howells if (n > ARRAY_SIZE(pages)) 53231143d5dSDavid Howells n = ARRAY_SIZE(pages); 5334343d008SDavid Howells n = find_get_pages_contig(mapping, start, ARRAY_SIZE(pages), pages); 53431143d5dSDavid Howells _debug("fgpc %u", n); 53531143d5dSDavid Howells if (n == 0) 53631143d5dSDavid Howells goto no_more; 53731143d5dSDavid Howells if (pages[0]->index != start) { 5389d577b6aSDavid Howells do { 5399d577b6aSDavid Howells put_page(pages[--n]); 5409d577b6aSDavid Howells } while (n > 0); 54131143d5dSDavid Howells goto no_more; 54231143d5dSDavid Howells } 54331143d5dSDavid Howells 54431143d5dSDavid Howells for (loop = 0; loop < n; loop++) { 54531143d5dSDavid Howells page = pages[loop]; 5465a813276SDavid Howells if (to != PAGE_SIZE && 5475a813276SDavid Howells !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)) 5485a813276SDavid Howells break; 5494343d008SDavid Howells if (page->index > final_page) 55031143d5dSDavid Howells break; 551529ae9aaSNick Piggin if (!trylock_page(page)) 55231143d5dSDavid Howells break; 5534343d008SDavid Howells if (!PageDirty(page) || PageWriteback(page)) { 55431143d5dSDavid Howells unlock_page(page); 55531143d5dSDavid Howells break; 55631143d5dSDavid Howells } 5574343d008SDavid Howells 5584343d008SDavid Howells priv = page_private(page); 55967d78a6fSDavid Howells f = afs_page_dirty_from(page, priv); 56067d78a6fSDavid Howells t = afs_page_dirty_to(page, priv); 5615a813276SDavid Howells if (f != 0 && 5625a813276SDavid Howells !test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags)) { 5634343d008SDavid Howells unlock_page(page); 5644343d008SDavid Howells break; 5654343d008SDavid Howells } 5664343d008SDavid Howells to = t; 5674343d008SDavid Howells 56867d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("store+"), page); 56913524ab3SDavid Howells 57031143d5dSDavid Howells if (!clear_page_dirty_for_io(page)) 57131143d5dSDavid Howells BUG(); 57231143d5dSDavid Howells if (test_set_page_writeback(page)) 57331143d5dSDavid Howells BUG(); 57431143d5dSDavid Howells unlock_page(page); 57531143d5dSDavid Howells put_page(page); 57631143d5dSDavid Howells } 57731143d5dSDavid Howells count += loop; 57831143d5dSDavid Howells if (loop < n) { 57931143d5dSDavid Howells for (; loop < n; loop++) 58031143d5dSDavid Howells put_page(pages[loop]); 58131143d5dSDavid Howells goto no_more; 58231143d5dSDavid Howells } 58331143d5dSDavid Howells 58431143d5dSDavid Howells start += loop; 5854343d008SDavid Howells } while (start <= final_page && count < 65536); 58631143d5dSDavid Howells 58731143d5dSDavid Howells no_more: 5884343d008SDavid Howells /* We now have a contiguous set of dirty pages, each with writeback 5894343d008SDavid Howells * set; the first page is still locked at this point, but all the rest 5904343d008SDavid Howells * have been unlocked. 5914343d008SDavid Howells */ 5924343d008SDavid Howells unlock_page(primary_page); 5934343d008SDavid Howells 59431143d5dSDavid Howells first = primary_page->index; 59531143d5dSDavid Howells last = first + count - 1; 59631143d5dSDavid Howells 597793fe82eSDavid Howells end = (loff_t)last * PAGE_SIZE + to; 598793fe82eSDavid Howells i_size = i_size_read(&vnode->vfs_inode); 599793fe82eSDavid Howells 60031143d5dSDavid Howells _debug("write back %lx[%u..] to %lx[..%u]", first, offset, last, to); 601793fe82eSDavid Howells if (end > i_size) 602793fe82eSDavid Howells to = i_size & ~PAGE_MASK; 60331143d5dSDavid Howells 604d383e346SDavid Howells ret = afs_store_data(mapping, first, last, offset, to, false); 60531143d5dSDavid Howells switch (ret) { 6064343d008SDavid Howells case 0: 6074343d008SDavid Howells ret = count; 6084343d008SDavid Howells break; 6094343d008SDavid Howells 6104343d008SDavid Howells default: 6114343d008SDavid Howells pr_notice("kAFS: Unexpected error from FS.StoreData %d\n", ret); 612df561f66SGustavo A. R. Silva fallthrough; 6134343d008SDavid Howells case -EACCES: 6144343d008SDavid Howells case -EPERM: 6154343d008SDavid Howells case -ENOKEY: 6164343d008SDavid Howells case -EKEYEXPIRED: 6174343d008SDavid Howells case -EKEYREJECTED: 6184343d008SDavid Howells case -EKEYREVOKED: 6194343d008SDavid Howells afs_redirty_pages(wbc, mapping, first, last); 6204343d008SDavid Howells mapping_set_error(mapping, ret); 6214343d008SDavid Howells break; 6224343d008SDavid Howells 62331143d5dSDavid Howells case -EDQUOT: 62431143d5dSDavid Howells case -ENOSPC: 6254343d008SDavid Howells afs_redirty_pages(wbc, mapping, first, last); 6264343d008SDavid Howells mapping_set_error(mapping, -ENOSPC); 62731143d5dSDavid Howells break; 6284343d008SDavid Howells 62931143d5dSDavid Howells case -EROFS: 63031143d5dSDavid Howells case -EIO: 63131143d5dSDavid Howells case -EREMOTEIO: 63231143d5dSDavid Howells case -EFBIG: 63331143d5dSDavid Howells case -ENOENT: 63431143d5dSDavid Howells case -ENOMEDIUM: 63531143d5dSDavid Howells case -ENXIO: 636f51375cdSDavid Howells trace_afs_file_error(vnode, ret, afs_file_error_writeback_fail); 6374343d008SDavid Howells afs_kill_pages(mapping, first, last); 6384343d008SDavid Howells mapping_set_error(mapping, ret); 63931143d5dSDavid Howells break; 64031143d5dSDavid Howells } 64131143d5dSDavid Howells 64231143d5dSDavid Howells _leave(" = %d", ret); 64331143d5dSDavid Howells return ret; 64431143d5dSDavid Howells } 64531143d5dSDavid Howells 64631143d5dSDavid Howells /* 64731143d5dSDavid Howells * write a page back to the server 64831143d5dSDavid Howells * - the caller locked the page for us 64931143d5dSDavid Howells */ 65031143d5dSDavid Howells int afs_writepage(struct page *page, struct writeback_control *wbc) 65131143d5dSDavid Howells { 65231143d5dSDavid Howells int ret; 65331143d5dSDavid Howells 65431143d5dSDavid Howells _enter("{%lx},", page->index); 65531143d5dSDavid Howells 6564343d008SDavid Howells ret = afs_write_back_from_locked_page(page->mapping, wbc, page, 6574343d008SDavid Howells wbc->range_end >> PAGE_SHIFT); 65831143d5dSDavid Howells if (ret < 0) { 65931143d5dSDavid Howells _leave(" = %d", ret); 66031143d5dSDavid Howells return 0; 66131143d5dSDavid Howells } 66231143d5dSDavid Howells 66331143d5dSDavid Howells wbc->nr_to_write -= ret; 66431143d5dSDavid Howells 66531143d5dSDavid Howells _leave(" = 0"); 66631143d5dSDavid Howells return 0; 66731143d5dSDavid Howells } 66831143d5dSDavid Howells 66931143d5dSDavid Howells /* 67031143d5dSDavid Howells * write a region of pages back to the server 67131143d5dSDavid Howells */ 672c1206a2cSAdrian Bunk static int afs_writepages_region(struct address_space *mapping, 67331143d5dSDavid Howells struct writeback_control *wbc, 67431143d5dSDavid Howells pgoff_t index, pgoff_t end, pgoff_t *_next) 67531143d5dSDavid Howells { 67631143d5dSDavid Howells struct page *page; 67731143d5dSDavid Howells int ret, n; 67831143d5dSDavid Howells 67931143d5dSDavid Howells _enter(",,%lx,%lx,", index, end); 68031143d5dSDavid Howells 68131143d5dSDavid Howells do { 682aef6e415SJan Kara n = find_get_pages_range_tag(mapping, &index, end, 683aef6e415SJan Kara PAGECACHE_TAG_DIRTY, 1, &page); 68431143d5dSDavid Howells if (!n) 68531143d5dSDavid Howells break; 68631143d5dSDavid Howells 68731143d5dSDavid Howells _debug("wback %lx", page->index); 68831143d5dSDavid Howells 689b93b0163SMatthew Wilcox /* 690b93b0163SMatthew Wilcox * at this point we hold neither the i_pages lock nor the 691b93b0163SMatthew Wilcox * page lock: the page may be truncated or invalidated 692b93b0163SMatthew Wilcox * (changing page->mapping to NULL), or even swizzled 693b93b0163SMatthew Wilcox * back from swapper_space to tmpfs file mapping 69431143d5dSDavid Howells */ 6954343d008SDavid Howells ret = lock_page_killable(page); 6964343d008SDavid Howells if (ret < 0) { 6974343d008SDavid Howells put_page(page); 6984343d008SDavid Howells _leave(" = %d", ret); 6994343d008SDavid Howells return ret; 7004343d008SDavid Howells } 70131143d5dSDavid Howells 702c5051c7bSDavid Howells if (page->mapping != mapping || !PageDirty(page)) { 70331143d5dSDavid Howells unlock_page(page); 70409cbfeafSKirill A. Shutemov put_page(page); 70531143d5dSDavid Howells continue; 70631143d5dSDavid Howells } 70731143d5dSDavid Howells 708c5051c7bSDavid Howells if (PageWriteback(page)) { 709c5051c7bSDavid Howells unlock_page(page); 71031143d5dSDavid Howells if (wbc->sync_mode != WB_SYNC_NONE) 71131143d5dSDavid Howells wait_on_page_writeback(page); 71229c8bbbdSDavid Howells put_page(page); 71331143d5dSDavid Howells continue; 71431143d5dSDavid Howells } 71531143d5dSDavid Howells 71665a15109SDavid Howells if (!clear_page_dirty_for_io(page)) 71765a15109SDavid Howells BUG(); 7184343d008SDavid Howells ret = afs_write_back_from_locked_page(mapping, wbc, page, end); 71909cbfeafSKirill A. Shutemov put_page(page); 72031143d5dSDavid Howells if (ret < 0) { 72131143d5dSDavid Howells _leave(" = %d", ret); 72231143d5dSDavid Howells return ret; 72331143d5dSDavid Howells } 72431143d5dSDavid Howells 72531143d5dSDavid Howells wbc->nr_to_write -= ret; 72631143d5dSDavid Howells 72731143d5dSDavid Howells cond_resched(); 72831143d5dSDavid Howells } while (index < end && wbc->nr_to_write > 0); 72931143d5dSDavid Howells 73031143d5dSDavid Howells *_next = index; 73131143d5dSDavid Howells _leave(" = 0 [%lx]", *_next); 73231143d5dSDavid Howells return 0; 73331143d5dSDavid Howells } 73431143d5dSDavid Howells 73531143d5dSDavid Howells /* 73631143d5dSDavid Howells * write some of the pending data back to the server 73731143d5dSDavid Howells */ 73831143d5dSDavid Howells int afs_writepages(struct address_space *mapping, 73931143d5dSDavid Howells struct writeback_control *wbc) 74031143d5dSDavid Howells { 741ec0fa0b6SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 74231143d5dSDavid Howells pgoff_t start, end, next; 74331143d5dSDavid Howells int ret; 74431143d5dSDavid Howells 74531143d5dSDavid Howells _enter(""); 74631143d5dSDavid Howells 747ec0fa0b6SDavid Howells /* We have to be careful as we can end up racing with setattr() 748ec0fa0b6SDavid Howells * truncating the pagecache since the caller doesn't take a lock here 749ec0fa0b6SDavid Howells * to prevent it. 750ec0fa0b6SDavid Howells */ 751ec0fa0b6SDavid Howells if (wbc->sync_mode == WB_SYNC_ALL) 752ec0fa0b6SDavid Howells down_read(&vnode->validate_lock); 753ec0fa0b6SDavid Howells else if (!down_read_trylock(&vnode->validate_lock)) 754ec0fa0b6SDavid Howells return 0; 755ec0fa0b6SDavid Howells 75631143d5dSDavid Howells if (wbc->range_cyclic) { 75731143d5dSDavid Howells start = mapping->writeback_index; 75831143d5dSDavid Howells end = -1; 75931143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, start, end, &next); 7601b430beeSWu Fengguang if (start > 0 && wbc->nr_to_write > 0 && ret == 0) 76131143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, 0, start, 76231143d5dSDavid Howells &next); 76331143d5dSDavid Howells mapping->writeback_index = next; 76431143d5dSDavid Howells } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) { 76509cbfeafSKirill A. Shutemov end = (pgoff_t)(LLONG_MAX >> PAGE_SHIFT); 76631143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, 0, end, &next); 76731143d5dSDavid Howells if (wbc->nr_to_write > 0) 76831143d5dSDavid Howells mapping->writeback_index = next; 76931143d5dSDavid Howells } else { 77009cbfeafSKirill A. Shutemov start = wbc->range_start >> PAGE_SHIFT; 77109cbfeafSKirill A. Shutemov end = wbc->range_end >> PAGE_SHIFT; 77231143d5dSDavid Howells ret = afs_writepages_region(mapping, wbc, start, end, &next); 77331143d5dSDavid Howells } 77431143d5dSDavid Howells 775ec0fa0b6SDavid Howells up_read(&vnode->validate_lock); 77631143d5dSDavid Howells _leave(" = %d", ret); 77731143d5dSDavid Howells return ret; 77831143d5dSDavid Howells } 77931143d5dSDavid Howells 78031143d5dSDavid Howells /* 78131143d5dSDavid Howells * write to an AFS file 78231143d5dSDavid Howells */ 78350b5551dSAl Viro ssize_t afs_file_write(struct kiocb *iocb, struct iov_iter *from) 78431143d5dSDavid Howells { 785496ad9aaSAl Viro struct afs_vnode *vnode = AFS_FS_I(file_inode(iocb->ki_filp)); 78631143d5dSDavid Howells ssize_t result; 78750b5551dSAl Viro size_t count = iov_iter_count(from); 78831143d5dSDavid Howells 7893b6492dfSDavid Howells _enter("{%llx:%llu},{%zu},", 79050b5551dSAl Viro vnode->fid.vid, vnode->fid.vnode, count); 79131143d5dSDavid Howells 79231143d5dSDavid Howells if (IS_SWAPFILE(&vnode->vfs_inode)) { 79331143d5dSDavid Howells printk(KERN_INFO 79431143d5dSDavid Howells "AFS: Attempt to write to active swap file!\n"); 79531143d5dSDavid Howells return -EBUSY; 79631143d5dSDavid Howells } 79731143d5dSDavid Howells 79831143d5dSDavid Howells if (!count) 79931143d5dSDavid Howells return 0; 80031143d5dSDavid Howells 80150b5551dSAl Viro result = generic_file_write_iter(iocb, from); 80231143d5dSDavid Howells 80331143d5dSDavid Howells _leave(" = %zd", result); 80431143d5dSDavid Howells return result; 80531143d5dSDavid Howells } 80631143d5dSDavid Howells 80731143d5dSDavid Howells /* 80831143d5dSDavid Howells * flush any dirty pages for this process, and check for write errors. 80931143d5dSDavid Howells * - the return status from this call provides a reliable indication of 81031143d5dSDavid Howells * whether any write errors occurred for this process. 81131143d5dSDavid Howells */ 81202c24a82SJosef Bacik int afs_fsync(struct file *file, loff_t start, loff_t end, int datasync) 81331143d5dSDavid Howells { 8143c981bfcSAl Viro struct inode *inode = file_inode(file); 8153c981bfcSAl Viro struct afs_vnode *vnode = AFS_FS_I(inode); 81631143d5dSDavid Howells 8173b6492dfSDavid Howells _enter("{%llx:%llu},{n=%pD},%d", 8183c981bfcSAl Viro vnode->fid.vid, vnode->fid.vnode, file, 81931143d5dSDavid Howells datasync); 82031143d5dSDavid Howells 8214343d008SDavid Howells return file_write_and_wait_range(file, start, end); 82231143d5dSDavid Howells } 8239b3f26c9SDavid Howells 8249b3f26c9SDavid Howells /* 8259b3f26c9SDavid Howells * notification that a previously read-only page is about to become writable 8269b3f26c9SDavid Howells * - if it returns an error, the caller will deliver a bus error signal 8279b3f26c9SDavid Howells */ 8280722f186SSouptick Joarder vm_fault_t afs_page_mkwrite(struct vm_fault *vmf) 8299b3f26c9SDavid Howells { 8301cf7a151SDavid Howells struct file *file = vmf->vma->vm_file; 8311cf7a151SDavid Howells struct inode *inode = file_inode(file); 8321cf7a151SDavid Howells struct afs_vnode *vnode = AFS_FS_I(inode); 8331cf7a151SDavid Howells unsigned long priv; 8349b3f26c9SDavid Howells 8353b6492dfSDavid Howells _enter("{{%llx:%llu}},{%lx}", 8361cf7a151SDavid Howells vnode->fid.vid, vnode->fid.vnode, vmf->page->index); 8379b3f26c9SDavid Howells 8381cf7a151SDavid Howells sb_start_pagefault(inode->i_sb); 8391cf7a151SDavid Howells 8401cf7a151SDavid Howells /* Wait for the page to be written to the cache before we allow it to 8411cf7a151SDavid Howells * be modified. We then assume the entire page will need writing back. 8421cf7a151SDavid Howells */ 8439b3f26c9SDavid Howells 84475b69799SMatthew Wilcox (Oracle) if (wait_on_page_writeback_killable(vmf->page)) 8451cf7a151SDavid Howells return VM_FAULT_RETRY; 8461cf7a151SDavid Howells 8471cf7a151SDavid Howells if (lock_page_killable(vmf->page) < 0) 8481cf7a151SDavid Howells return VM_FAULT_RETRY; 8491cf7a151SDavid Howells 8501cf7a151SDavid Howells /* We mustn't change page->private until writeback is complete as that 8511cf7a151SDavid Howells * details the portion of the page we need to write back and we might 8521cf7a151SDavid Howells * need to redirty the page if there's a problem. 8531cf7a151SDavid Howells */ 8541cf7a151SDavid Howells wait_on_page_writeback(vmf->page); 8551cf7a151SDavid Howells 85667d78a6fSDavid Howells priv = afs_page_dirty(vmf->page, 0, PAGE_SIZE); 857f86726a6SDavid Howells priv = afs_page_dirty_mmapped(priv); 858fa04a40bSDavid Howells if (PagePrivate(vmf->page)) 8591cf7a151SDavid Howells set_page_private(vmf->page, priv); 860fa04a40bSDavid Howells else 861fa04a40bSDavid Howells attach_page_private(vmf->page, (void *)priv); 86267d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("mkwrite"), vmf->page); 863bb413489SDavid Howells file_update_time(file); 8641cf7a151SDavid Howells 8651cf7a151SDavid Howells sb_end_pagefault(inode->i_sb); 8661cf7a151SDavid Howells return VM_FAULT_LOCKED; 8679b3f26c9SDavid Howells } 8684343d008SDavid Howells 8694343d008SDavid Howells /* 8704343d008SDavid Howells * Prune the keys cached for writeback. The caller must hold vnode->wb_lock. 8714343d008SDavid Howells */ 8724343d008SDavid Howells void afs_prune_wb_keys(struct afs_vnode *vnode) 8734343d008SDavid Howells { 8744343d008SDavid Howells LIST_HEAD(graveyard); 8754343d008SDavid Howells struct afs_wb_key *wbk, *tmp; 8764343d008SDavid Howells 8774343d008SDavid Howells /* Discard unused keys */ 8784343d008SDavid Howells spin_lock(&vnode->wb_lock); 8794343d008SDavid Howells 8804343d008SDavid Howells if (!mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_WRITEBACK) && 8814343d008SDavid Howells !mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_DIRTY)) { 8824343d008SDavid Howells list_for_each_entry_safe(wbk, tmp, &vnode->wb_keys, vnode_link) { 8834343d008SDavid Howells if (refcount_read(&wbk->usage) == 1) 8844343d008SDavid Howells list_move(&wbk->vnode_link, &graveyard); 8854343d008SDavid Howells } 8864343d008SDavid Howells } 8874343d008SDavid Howells 8884343d008SDavid Howells spin_unlock(&vnode->wb_lock); 8894343d008SDavid Howells 8904343d008SDavid Howells while (!list_empty(&graveyard)) { 8914343d008SDavid Howells wbk = list_entry(graveyard.next, struct afs_wb_key, vnode_link); 8924343d008SDavid Howells list_del(&wbk->vnode_link); 8934343d008SDavid Howells afs_put_wb_key(wbk); 8944343d008SDavid Howells } 8954343d008SDavid Howells } 8964343d008SDavid Howells 8974343d008SDavid Howells /* 8984343d008SDavid Howells * Clean up a page during invalidation. 8994343d008SDavid Howells */ 9004343d008SDavid Howells int afs_launder_page(struct page *page) 9014343d008SDavid Howells { 9024343d008SDavid Howells struct address_space *mapping = page->mapping; 9034343d008SDavid Howells struct afs_vnode *vnode = AFS_FS_I(mapping->host); 9044343d008SDavid Howells unsigned long priv; 9054343d008SDavid Howells unsigned int f, t; 9064343d008SDavid Howells int ret = 0; 9074343d008SDavid Howells 9084343d008SDavid Howells _enter("{%lx}", page->index); 9094343d008SDavid Howells 9104343d008SDavid Howells priv = page_private(page); 9114343d008SDavid Howells if (clear_page_dirty_for_io(page)) { 9124343d008SDavid Howells f = 0; 9134343d008SDavid Howells t = PAGE_SIZE; 9144343d008SDavid Howells if (PagePrivate(page)) { 91567d78a6fSDavid Howells f = afs_page_dirty_from(page, priv); 91667d78a6fSDavid Howells t = afs_page_dirty_to(page, priv); 9174343d008SDavid Howells } 9184343d008SDavid Howells 91967d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("launder"), page); 920d383e346SDavid Howells ret = afs_store_data(mapping, page->index, page->index, t, f, true); 9214343d008SDavid Howells } 9224343d008SDavid Howells 92367d78a6fSDavid Howells detach_page_private(page); 92467d78a6fSDavid Howells trace_afs_page_dirty(vnode, tracepoint_string("laundered"), page); 9254343d008SDavid Howells return ret; 92631143d5dSDavid Howells } 927