11bd9c4e4SDavid Howells // SPDX-License-Identifier: GPL-2.0-or-later 21bd9c4e4SDavid Howells /* CacheFiles path walking and related routines 31bd9c4e4SDavid Howells * 41bd9c4e4SDavid Howells * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved. 51bd9c4e4SDavid Howells * Written by David Howells (dhowells@redhat.com) 61bd9c4e4SDavid Howells */ 71bd9c4e4SDavid Howells 81bd9c4e4SDavid Howells #include <linux/fs.h> 932759f7dSDavid Howells #include <linux/namei.h> 101bd9c4e4SDavid Howells #include "internal.h" 111bd9c4e4SDavid Howells 121bd9c4e4SDavid Howells /* 131bd9c4e4SDavid Howells * Mark the backing file as being a cache file if it's not already in use. The 141bd9c4e4SDavid Howells * mark tells the culling request command that it's not allowed to cull the 151bd9c4e4SDavid Howells * file or directory. The caller must hold the inode lock. 161bd9c4e4SDavid Howells */ 171bd9c4e4SDavid Howells static bool __cachefiles_mark_inode_in_use(struct cachefiles_object *object, 181bd9c4e4SDavid Howells struct dentry *dentry) 191bd9c4e4SDavid Howells { 201bd9c4e4SDavid Howells struct inode *inode = d_backing_inode(dentry); 211bd9c4e4SDavid Howells bool can_use = false; 221bd9c4e4SDavid Howells 231bd9c4e4SDavid Howells if (!(inode->i_flags & S_KERNEL_FILE)) { 241bd9c4e4SDavid Howells inode->i_flags |= S_KERNEL_FILE; 251bd9c4e4SDavid Howells trace_cachefiles_mark_active(object, inode); 261bd9c4e4SDavid Howells can_use = true; 271bd9c4e4SDavid Howells } else { 281bd9c4e4SDavid Howells pr_notice("cachefiles: Inode already in use: %pd\n", dentry); 291bd9c4e4SDavid Howells } 301bd9c4e4SDavid Howells 311bd9c4e4SDavid Howells return can_use; 321bd9c4e4SDavid Howells } 331bd9c4e4SDavid Howells 34169379eaSDavid Howells static bool cachefiles_mark_inode_in_use(struct cachefiles_object *object, 35169379eaSDavid Howells struct dentry *dentry) 36169379eaSDavid Howells { 37169379eaSDavid Howells struct inode *inode = d_backing_inode(dentry); 38169379eaSDavid Howells bool can_use; 39169379eaSDavid Howells 40169379eaSDavid Howells inode_lock(inode); 41169379eaSDavid Howells can_use = __cachefiles_mark_inode_in_use(object, dentry); 42169379eaSDavid Howells inode_unlock(inode); 43169379eaSDavid Howells return can_use; 44169379eaSDavid Howells } 45169379eaSDavid Howells 461bd9c4e4SDavid Howells /* 471bd9c4e4SDavid Howells * Unmark a backing inode. The caller must hold the inode lock. 481bd9c4e4SDavid Howells */ 491bd9c4e4SDavid Howells static void __cachefiles_unmark_inode_in_use(struct cachefiles_object *object, 501bd9c4e4SDavid Howells struct dentry *dentry) 511bd9c4e4SDavid Howells { 521bd9c4e4SDavid Howells struct inode *inode = d_backing_inode(dentry); 531bd9c4e4SDavid Howells 541bd9c4e4SDavid Howells inode->i_flags &= ~S_KERNEL_FILE; 551bd9c4e4SDavid Howells trace_cachefiles_mark_inactive(object, inode); 561bd9c4e4SDavid Howells } 5732759f7dSDavid Howells 5832759f7dSDavid Howells /* 59169379eaSDavid Howells * Unmark a backing inode and tell cachefilesd that there's something that can 60169379eaSDavid Howells * be culled. 61169379eaSDavid Howells */ 62169379eaSDavid Howells void cachefiles_unmark_inode_in_use(struct cachefiles_object *object, 63169379eaSDavid Howells struct file *file) 64169379eaSDavid Howells { 65169379eaSDavid Howells struct cachefiles_cache *cache = object->volume->cache; 66169379eaSDavid Howells struct inode *inode = file_inode(file); 67169379eaSDavid Howells 68169379eaSDavid Howells if (inode) { 69169379eaSDavid Howells inode_lock(inode); 70169379eaSDavid Howells __cachefiles_unmark_inode_in_use(object, file->f_path.dentry); 71169379eaSDavid Howells inode_unlock(inode); 72169379eaSDavid Howells 73169379eaSDavid Howells if (!test_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags)) { 74169379eaSDavid Howells atomic_long_add(inode->i_blocks, &cache->b_released); 75169379eaSDavid Howells if (atomic_inc_return(&cache->f_released)) 76169379eaSDavid Howells cachefiles_state_changed(cache); 77169379eaSDavid Howells } 78169379eaSDavid Howells } 79169379eaSDavid Howells } 80169379eaSDavid Howells 81169379eaSDavid Howells /* 8232759f7dSDavid Howells * get a subdirectory 8332759f7dSDavid Howells */ 8432759f7dSDavid Howells struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache, 8532759f7dSDavid Howells struct dentry *dir, 8632759f7dSDavid Howells const char *dirname, 8732759f7dSDavid Howells bool *_is_new) 8832759f7dSDavid Howells { 8932759f7dSDavid Howells struct dentry *subdir; 9032759f7dSDavid Howells struct path path; 9132759f7dSDavid Howells int ret; 9232759f7dSDavid Howells 9332759f7dSDavid Howells _enter(",,%s", dirname); 9432759f7dSDavid Howells 9532759f7dSDavid Howells /* search the current directory for the element name */ 9632759f7dSDavid Howells inode_lock_nested(d_inode(dir), I_MUTEX_PARENT); 9732759f7dSDavid Howells 9832759f7dSDavid Howells retry: 9932759f7dSDavid Howells ret = cachefiles_inject_read_error(); 10032759f7dSDavid Howells if (ret == 0) 10132759f7dSDavid Howells subdir = lookup_one_len(dirname, dir, strlen(dirname)); 10232759f7dSDavid Howells else 10332759f7dSDavid Howells subdir = ERR_PTR(ret); 10432759f7dSDavid Howells if (IS_ERR(subdir)) { 10532759f7dSDavid Howells trace_cachefiles_vfs_error(NULL, d_backing_inode(dir), 10632759f7dSDavid Howells PTR_ERR(subdir), 10732759f7dSDavid Howells cachefiles_trace_lookup_error); 10832759f7dSDavid Howells if (PTR_ERR(subdir) == -ENOMEM) 10932759f7dSDavid Howells goto nomem_d_alloc; 11032759f7dSDavid Howells goto lookup_error; 11132759f7dSDavid Howells } 11232759f7dSDavid Howells 11332759f7dSDavid Howells _debug("subdir -> %pd %s", 11432759f7dSDavid Howells subdir, d_backing_inode(subdir) ? "positive" : "negative"); 11532759f7dSDavid Howells 11632759f7dSDavid Howells /* we need to create the subdir if it doesn't exist yet */ 11732759f7dSDavid Howells if (d_is_negative(subdir)) { 11832759f7dSDavid Howells ret = cachefiles_has_space(cache, 1, 0); 11932759f7dSDavid Howells if (ret < 0) 12032759f7dSDavid Howells goto mkdir_error; 12132759f7dSDavid Howells 12232759f7dSDavid Howells _debug("attempt mkdir"); 12332759f7dSDavid Howells 12432759f7dSDavid Howells path.mnt = cache->mnt; 12532759f7dSDavid Howells path.dentry = dir; 12632759f7dSDavid Howells ret = security_path_mkdir(&path, subdir, 0700); 12732759f7dSDavid Howells if (ret < 0) 12832759f7dSDavid Howells goto mkdir_error; 12932759f7dSDavid Howells ret = cachefiles_inject_write_error(); 13032759f7dSDavid Howells if (ret == 0) 13132759f7dSDavid Howells ret = vfs_mkdir(&init_user_ns, d_inode(dir), subdir, 0700); 13232759f7dSDavid Howells if (ret < 0) { 13332759f7dSDavid Howells trace_cachefiles_vfs_error(NULL, d_inode(dir), ret, 13432759f7dSDavid Howells cachefiles_trace_mkdir_error); 13532759f7dSDavid Howells goto mkdir_error; 13632759f7dSDavid Howells } 13732759f7dSDavid Howells 13832759f7dSDavid Howells if (unlikely(d_unhashed(subdir))) { 13932759f7dSDavid Howells cachefiles_put_directory(subdir); 14032759f7dSDavid Howells goto retry; 14132759f7dSDavid Howells } 14232759f7dSDavid Howells ASSERT(d_backing_inode(subdir)); 14332759f7dSDavid Howells 14432759f7dSDavid Howells _debug("mkdir -> %pd{ino=%lu}", 14532759f7dSDavid Howells subdir, d_backing_inode(subdir)->i_ino); 14632759f7dSDavid Howells if (_is_new) 14732759f7dSDavid Howells *_is_new = true; 14832759f7dSDavid Howells } 14932759f7dSDavid Howells 15032759f7dSDavid Howells /* Tell rmdir() it's not allowed to delete the subdir */ 15132759f7dSDavid Howells inode_lock(d_inode(subdir)); 15232759f7dSDavid Howells inode_unlock(d_inode(dir)); 15332759f7dSDavid Howells 15432759f7dSDavid Howells if (!__cachefiles_mark_inode_in_use(NULL, subdir)) 15532759f7dSDavid Howells goto mark_error; 15632759f7dSDavid Howells 15732759f7dSDavid Howells inode_unlock(d_inode(subdir)); 15832759f7dSDavid Howells 15932759f7dSDavid Howells /* we need to make sure the subdir is a directory */ 16032759f7dSDavid Howells ASSERT(d_backing_inode(subdir)); 16132759f7dSDavid Howells 16232759f7dSDavid Howells if (!d_can_lookup(subdir)) { 16332759f7dSDavid Howells pr_err("%s is not a directory\n", dirname); 16432759f7dSDavid Howells ret = -EIO; 16532759f7dSDavid Howells goto check_error; 16632759f7dSDavid Howells } 16732759f7dSDavid Howells 16832759f7dSDavid Howells ret = -EPERM; 16932759f7dSDavid Howells if (!(d_backing_inode(subdir)->i_opflags & IOP_XATTR) || 17032759f7dSDavid Howells !d_backing_inode(subdir)->i_op->lookup || 17132759f7dSDavid Howells !d_backing_inode(subdir)->i_op->mkdir || 17232759f7dSDavid Howells !d_backing_inode(subdir)->i_op->rename || 17332759f7dSDavid Howells !d_backing_inode(subdir)->i_op->rmdir || 17432759f7dSDavid Howells !d_backing_inode(subdir)->i_op->unlink) 17532759f7dSDavid Howells goto check_error; 17632759f7dSDavid Howells 17732759f7dSDavid Howells _leave(" = [%lu]", d_backing_inode(subdir)->i_ino); 17832759f7dSDavid Howells return subdir; 17932759f7dSDavid Howells 18032759f7dSDavid Howells check_error: 18132759f7dSDavid Howells cachefiles_put_directory(subdir); 18232759f7dSDavid Howells _leave(" = %d [check]", ret); 18332759f7dSDavid Howells return ERR_PTR(ret); 18432759f7dSDavid Howells 18532759f7dSDavid Howells mark_error: 18632759f7dSDavid Howells inode_unlock(d_inode(subdir)); 18732759f7dSDavid Howells dput(subdir); 18832759f7dSDavid Howells return ERR_PTR(-EBUSY); 18932759f7dSDavid Howells 19032759f7dSDavid Howells mkdir_error: 19132759f7dSDavid Howells inode_unlock(d_inode(dir)); 19232759f7dSDavid Howells dput(subdir); 19332759f7dSDavid Howells pr_err("mkdir %s failed with error %d\n", dirname, ret); 19432759f7dSDavid Howells return ERR_PTR(ret); 19532759f7dSDavid Howells 19632759f7dSDavid Howells lookup_error: 19732759f7dSDavid Howells inode_unlock(d_inode(dir)); 19832759f7dSDavid Howells ret = PTR_ERR(subdir); 19932759f7dSDavid Howells pr_err("Lookup %s failed with error %d\n", dirname, ret); 20032759f7dSDavid Howells return ERR_PTR(ret); 20132759f7dSDavid Howells 20232759f7dSDavid Howells nomem_d_alloc: 20332759f7dSDavid Howells inode_unlock(d_inode(dir)); 20432759f7dSDavid Howells _leave(" = -ENOMEM"); 20532759f7dSDavid Howells return ERR_PTR(-ENOMEM); 20632759f7dSDavid Howells } 20732759f7dSDavid Howells 20832759f7dSDavid Howells /* 20932759f7dSDavid Howells * Put a subdirectory. 21032759f7dSDavid Howells */ 21132759f7dSDavid Howells void cachefiles_put_directory(struct dentry *dir) 21232759f7dSDavid Howells { 21332759f7dSDavid Howells if (dir) { 21432759f7dSDavid Howells inode_lock(dir->d_inode); 21532759f7dSDavid Howells __cachefiles_unmark_inode_in_use(NULL, dir); 21632759f7dSDavid Howells inode_unlock(dir->d_inode); 21732759f7dSDavid Howells dput(dir); 21832759f7dSDavid Howells } 21932759f7dSDavid Howells } 22007a90e97SDavid Howells 22107a90e97SDavid Howells /* 22207a90e97SDavid Howells * Remove a regular file from the cache. 22307a90e97SDavid Howells */ 22407a90e97SDavid Howells static int cachefiles_unlink(struct cachefiles_cache *cache, 22507a90e97SDavid Howells struct cachefiles_object *object, 22607a90e97SDavid Howells struct dentry *dir, struct dentry *dentry, 22707a90e97SDavid Howells enum fscache_why_object_killed why) 22807a90e97SDavid Howells { 22907a90e97SDavid Howells struct path path = { 23007a90e97SDavid Howells .mnt = cache->mnt, 23107a90e97SDavid Howells .dentry = dir, 23207a90e97SDavid Howells }; 23307a90e97SDavid Howells int ret; 23407a90e97SDavid Howells 23507a90e97SDavid Howells trace_cachefiles_unlink(object, dentry, why); 23607a90e97SDavid Howells ret = security_path_unlink(&path, dentry); 23707a90e97SDavid Howells if (ret < 0) { 23807a90e97SDavid Howells cachefiles_io_error(cache, "Unlink security error"); 23907a90e97SDavid Howells return ret; 24007a90e97SDavid Howells } 24107a90e97SDavid Howells 24207a90e97SDavid Howells ret = cachefiles_inject_remove_error(); 24307a90e97SDavid Howells if (ret == 0) { 24407a90e97SDavid Howells ret = vfs_unlink(&init_user_ns, d_backing_inode(dir), dentry, NULL); 24507a90e97SDavid Howells if (ret == -EIO) 24607a90e97SDavid Howells cachefiles_io_error(cache, "Unlink failed"); 24707a90e97SDavid Howells } 24807a90e97SDavid Howells if (ret != 0) 24907a90e97SDavid Howells trace_cachefiles_vfs_error(object, d_backing_inode(dir), ret, 25007a90e97SDavid Howells cachefiles_trace_unlink_error); 25107a90e97SDavid Howells return ret; 25207a90e97SDavid Howells } 25307a90e97SDavid Howells 25407a90e97SDavid Howells /* 25507a90e97SDavid Howells * Delete an object representation from the cache 25607a90e97SDavid Howells * - File backed objects are unlinked 25707a90e97SDavid Howells * - Directory backed objects are stuffed into the graveyard for userspace to 25807a90e97SDavid Howells * delete 25907a90e97SDavid Howells */ 26007a90e97SDavid Howells int cachefiles_bury_object(struct cachefiles_cache *cache, 26107a90e97SDavid Howells struct cachefiles_object *object, 26207a90e97SDavid Howells struct dentry *dir, 26307a90e97SDavid Howells struct dentry *rep, 26407a90e97SDavid Howells enum fscache_why_object_killed why) 26507a90e97SDavid Howells { 26607a90e97SDavid Howells struct dentry *grave, *trap; 26707a90e97SDavid Howells struct path path, path_to_graveyard; 26807a90e97SDavid Howells char nbuffer[8 + 8 + 1]; 26907a90e97SDavid Howells int ret; 27007a90e97SDavid Howells 27107a90e97SDavid Howells _enter(",'%pd','%pd'", dir, rep); 27207a90e97SDavid Howells 27307a90e97SDavid Howells if (rep->d_parent != dir) { 27407a90e97SDavid Howells inode_unlock(d_inode(dir)); 27507a90e97SDavid Howells _leave(" = -ESTALE"); 27607a90e97SDavid Howells return -ESTALE; 27707a90e97SDavid Howells } 27807a90e97SDavid Howells 27907a90e97SDavid Howells /* non-directories can just be unlinked */ 28007a90e97SDavid Howells if (!d_is_dir(rep)) { 28107a90e97SDavid Howells dget(rep); /* Stop the dentry being negated if it's only pinned 28207a90e97SDavid Howells * by a file struct. 28307a90e97SDavid Howells */ 28407a90e97SDavid Howells ret = cachefiles_unlink(cache, object, dir, rep, why); 28507a90e97SDavid Howells dput(rep); 28607a90e97SDavid Howells 28707a90e97SDavid Howells inode_unlock(d_inode(dir)); 28807a90e97SDavid Howells _leave(" = %d", ret); 28907a90e97SDavid Howells return ret; 29007a90e97SDavid Howells } 29107a90e97SDavid Howells 29207a90e97SDavid Howells /* directories have to be moved to the graveyard */ 29307a90e97SDavid Howells _debug("move stale object to graveyard"); 29407a90e97SDavid Howells inode_unlock(d_inode(dir)); 29507a90e97SDavid Howells 29607a90e97SDavid Howells try_again: 29707a90e97SDavid Howells /* first step is to make up a grave dentry in the graveyard */ 29807a90e97SDavid Howells sprintf(nbuffer, "%08x%08x", 29907a90e97SDavid Howells (uint32_t) ktime_get_real_seconds(), 30007a90e97SDavid Howells (uint32_t) atomic_inc_return(&cache->gravecounter)); 30107a90e97SDavid Howells 30207a90e97SDavid Howells /* do the multiway lock magic */ 30307a90e97SDavid Howells trap = lock_rename(cache->graveyard, dir); 30407a90e97SDavid Howells 30507a90e97SDavid Howells /* do some checks before getting the grave dentry */ 30607a90e97SDavid Howells if (rep->d_parent != dir || IS_DEADDIR(d_inode(rep))) { 30707a90e97SDavid Howells /* the entry was probably culled when we dropped the parent dir 30807a90e97SDavid Howells * lock */ 30907a90e97SDavid Howells unlock_rename(cache->graveyard, dir); 31007a90e97SDavid Howells _leave(" = 0 [culled?]"); 31107a90e97SDavid Howells return 0; 31207a90e97SDavid Howells } 31307a90e97SDavid Howells 31407a90e97SDavid Howells if (!d_can_lookup(cache->graveyard)) { 31507a90e97SDavid Howells unlock_rename(cache->graveyard, dir); 31607a90e97SDavid Howells cachefiles_io_error(cache, "Graveyard no longer a directory"); 31707a90e97SDavid Howells return -EIO; 31807a90e97SDavid Howells } 31907a90e97SDavid Howells 32007a90e97SDavid Howells if (trap == rep) { 32107a90e97SDavid Howells unlock_rename(cache->graveyard, dir); 32207a90e97SDavid Howells cachefiles_io_error(cache, "May not make directory loop"); 32307a90e97SDavid Howells return -EIO; 32407a90e97SDavid Howells } 32507a90e97SDavid Howells 32607a90e97SDavid Howells if (d_mountpoint(rep)) { 32707a90e97SDavid Howells unlock_rename(cache->graveyard, dir); 32807a90e97SDavid Howells cachefiles_io_error(cache, "Mountpoint in cache"); 32907a90e97SDavid Howells return -EIO; 33007a90e97SDavid Howells } 33107a90e97SDavid Howells 33207a90e97SDavid Howells grave = lookup_one_len(nbuffer, cache->graveyard, strlen(nbuffer)); 33307a90e97SDavid Howells if (IS_ERR(grave)) { 33407a90e97SDavid Howells unlock_rename(cache->graveyard, dir); 33507a90e97SDavid Howells trace_cachefiles_vfs_error(object, d_inode(cache->graveyard), 33607a90e97SDavid Howells PTR_ERR(grave), 33707a90e97SDavid Howells cachefiles_trace_lookup_error); 33807a90e97SDavid Howells 33907a90e97SDavid Howells if (PTR_ERR(grave) == -ENOMEM) { 34007a90e97SDavid Howells _leave(" = -ENOMEM"); 34107a90e97SDavid Howells return -ENOMEM; 34207a90e97SDavid Howells } 34307a90e97SDavid Howells 34407a90e97SDavid Howells cachefiles_io_error(cache, "Lookup error %ld", PTR_ERR(grave)); 34507a90e97SDavid Howells return -EIO; 34607a90e97SDavid Howells } 34707a90e97SDavid Howells 34807a90e97SDavid Howells if (d_is_positive(grave)) { 34907a90e97SDavid Howells unlock_rename(cache->graveyard, dir); 35007a90e97SDavid Howells dput(grave); 35107a90e97SDavid Howells grave = NULL; 35207a90e97SDavid Howells cond_resched(); 35307a90e97SDavid Howells goto try_again; 35407a90e97SDavid Howells } 35507a90e97SDavid Howells 35607a90e97SDavid Howells if (d_mountpoint(grave)) { 35707a90e97SDavid Howells unlock_rename(cache->graveyard, dir); 35807a90e97SDavid Howells dput(grave); 35907a90e97SDavid Howells cachefiles_io_error(cache, "Mountpoint in graveyard"); 36007a90e97SDavid Howells return -EIO; 36107a90e97SDavid Howells } 36207a90e97SDavid Howells 36307a90e97SDavid Howells /* target should not be an ancestor of source */ 36407a90e97SDavid Howells if (trap == grave) { 36507a90e97SDavid Howells unlock_rename(cache->graveyard, dir); 36607a90e97SDavid Howells dput(grave); 36707a90e97SDavid Howells cachefiles_io_error(cache, "May not make directory loop"); 36807a90e97SDavid Howells return -EIO; 36907a90e97SDavid Howells } 37007a90e97SDavid Howells 37107a90e97SDavid Howells /* attempt the rename */ 37207a90e97SDavid Howells path.mnt = cache->mnt; 37307a90e97SDavid Howells path.dentry = dir; 37407a90e97SDavid Howells path_to_graveyard.mnt = cache->mnt; 37507a90e97SDavid Howells path_to_graveyard.dentry = cache->graveyard; 37607a90e97SDavid Howells ret = security_path_rename(&path, rep, &path_to_graveyard, grave, 0); 37707a90e97SDavid Howells if (ret < 0) { 37807a90e97SDavid Howells cachefiles_io_error(cache, "Rename security error %d", ret); 37907a90e97SDavid Howells } else { 38007a90e97SDavid Howells struct renamedata rd = { 38107a90e97SDavid Howells .old_mnt_userns = &init_user_ns, 38207a90e97SDavid Howells .old_dir = d_inode(dir), 38307a90e97SDavid Howells .old_dentry = rep, 38407a90e97SDavid Howells .new_mnt_userns = &init_user_ns, 38507a90e97SDavid Howells .new_dir = d_inode(cache->graveyard), 38607a90e97SDavid Howells .new_dentry = grave, 38707a90e97SDavid Howells }; 38807a90e97SDavid Howells trace_cachefiles_rename(object, rep, grave, why); 38907a90e97SDavid Howells ret = cachefiles_inject_read_error(); 39007a90e97SDavid Howells if (ret == 0) 39107a90e97SDavid Howells ret = vfs_rename(&rd); 39207a90e97SDavid Howells if (ret != 0) 39307a90e97SDavid Howells trace_cachefiles_vfs_error(object, d_inode(dir), ret, 39407a90e97SDavid Howells cachefiles_trace_rename_error); 39507a90e97SDavid Howells if (ret != 0 && ret != -ENOMEM) 39607a90e97SDavid Howells cachefiles_io_error(cache, 39707a90e97SDavid Howells "Rename failed with error %d", ret); 39807a90e97SDavid Howells } 39907a90e97SDavid Howells 40007a90e97SDavid Howells __cachefiles_unmark_inode_in_use(object, rep); 40107a90e97SDavid Howells unlock_rename(cache->graveyard, dir); 40207a90e97SDavid Howells dput(grave); 40307a90e97SDavid Howells _leave(" = 0"); 40407a90e97SDavid Howells return 0; 40507a90e97SDavid Howells } 40607a90e97SDavid Howells 40707a90e97SDavid Howells /* 408*1f08c925SDavid Howells * Delete a cache file. 409*1f08c925SDavid Howells */ 410*1f08c925SDavid Howells int cachefiles_delete_object(struct cachefiles_object *object, 411*1f08c925SDavid Howells enum fscache_why_object_killed why) 412*1f08c925SDavid Howells { 413*1f08c925SDavid Howells struct cachefiles_volume *volume = object->volume; 414*1f08c925SDavid Howells struct dentry *dentry = object->file->f_path.dentry; 415*1f08c925SDavid Howells struct dentry *fan = volume->fanout[(u8)object->cookie->key_hash]; 416*1f08c925SDavid Howells int ret; 417*1f08c925SDavid Howells 418*1f08c925SDavid Howells _enter(",OBJ%x{%pD}", object->debug_id, object->file); 419*1f08c925SDavid Howells 420*1f08c925SDavid Howells /* Stop the dentry being negated if it's only pinned by a file struct. */ 421*1f08c925SDavid Howells dget(dentry); 422*1f08c925SDavid Howells 423*1f08c925SDavid Howells inode_lock_nested(d_backing_inode(fan), I_MUTEX_PARENT); 424*1f08c925SDavid Howells ret = cachefiles_unlink(volume->cache, object, fan, dentry, why); 425*1f08c925SDavid Howells inode_unlock(d_backing_inode(fan)); 426*1f08c925SDavid Howells dput(dentry); 427*1f08c925SDavid Howells return ret; 428*1f08c925SDavid Howells } 429*1f08c925SDavid Howells 430*1f08c925SDavid Howells /* 431*1f08c925SDavid Howells * Create a temporary file and leave it unattached and un-xattr'd until the 432*1f08c925SDavid Howells * time comes to discard the object from memory. 433*1f08c925SDavid Howells */ 434*1f08c925SDavid Howells struct file *cachefiles_create_tmpfile(struct cachefiles_object *object) 435*1f08c925SDavid Howells { 436*1f08c925SDavid Howells struct cachefiles_volume *volume = object->volume; 437*1f08c925SDavid Howells struct cachefiles_cache *cache = volume->cache; 438*1f08c925SDavid Howells const struct cred *saved_cred; 439*1f08c925SDavid Howells struct dentry *fan = volume->fanout[(u8)object->cookie->key_hash]; 440*1f08c925SDavid Howells struct file *file; 441*1f08c925SDavid Howells struct path path; 442*1f08c925SDavid Howells uint64_t ni_size = object->cookie->object_size; 443*1f08c925SDavid Howells long ret; 444*1f08c925SDavid Howells 445*1f08c925SDavid Howells ni_size = round_up(ni_size, CACHEFILES_DIO_BLOCK_SIZE); 446*1f08c925SDavid Howells 447*1f08c925SDavid Howells cachefiles_begin_secure(cache, &saved_cred); 448*1f08c925SDavid Howells 449*1f08c925SDavid Howells path.mnt = cache->mnt; 450*1f08c925SDavid Howells ret = cachefiles_inject_write_error(); 451*1f08c925SDavid Howells if (ret == 0) 452*1f08c925SDavid Howells path.dentry = vfs_tmpfile(&init_user_ns, fan, S_IFREG, O_RDWR); 453*1f08c925SDavid Howells else 454*1f08c925SDavid Howells path.dentry = ERR_PTR(ret); 455*1f08c925SDavid Howells if (IS_ERR(path.dentry)) { 456*1f08c925SDavid Howells trace_cachefiles_vfs_error(object, d_inode(fan), PTR_ERR(path.dentry), 457*1f08c925SDavid Howells cachefiles_trace_tmpfile_error); 458*1f08c925SDavid Howells if (PTR_ERR(path.dentry) == -EIO) 459*1f08c925SDavid Howells cachefiles_io_error_obj(object, "Failed to create tmpfile"); 460*1f08c925SDavid Howells file = ERR_CAST(path.dentry); 461*1f08c925SDavid Howells goto out; 462*1f08c925SDavid Howells } 463*1f08c925SDavid Howells 464*1f08c925SDavid Howells trace_cachefiles_tmpfile(object, d_backing_inode(path.dentry)); 465*1f08c925SDavid Howells 466*1f08c925SDavid Howells if (!cachefiles_mark_inode_in_use(object, path.dentry)) { 467*1f08c925SDavid Howells file = ERR_PTR(-EBUSY); 468*1f08c925SDavid Howells goto out_dput; 469*1f08c925SDavid Howells } 470*1f08c925SDavid Howells 471*1f08c925SDavid Howells if (ni_size > 0) { 472*1f08c925SDavid Howells trace_cachefiles_trunc(object, d_backing_inode(path.dentry), 0, ni_size, 473*1f08c925SDavid Howells cachefiles_trunc_expand_tmpfile); 474*1f08c925SDavid Howells ret = cachefiles_inject_write_error(); 475*1f08c925SDavid Howells if (ret == 0) 476*1f08c925SDavid Howells ret = vfs_truncate(&path, ni_size); 477*1f08c925SDavid Howells if (ret < 0) { 478*1f08c925SDavid Howells trace_cachefiles_vfs_error( 479*1f08c925SDavid Howells object, d_backing_inode(path.dentry), ret, 480*1f08c925SDavid Howells cachefiles_trace_trunc_error); 481*1f08c925SDavid Howells file = ERR_PTR(ret); 482*1f08c925SDavid Howells goto out_dput; 483*1f08c925SDavid Howells } 484*1f08c925SDavid Howells } 485*1f08c925SDavid Howells 486*1f08c925SDavid Howells file = open_with_fake_path(&path, O_RDWR | O_LARGEFILE | O_DIRECT, 487*1f08c925SDavid Howells d_backing_inode(path.dentry), cache->cache_cred); 488*1f08c925SDavid Howells if (IS_ERR(file)) { 489*1f08c925SDavid Howells trace_cachefiles_vfs_error(object, d_backing_inode(path.dentry), 490*1f08c925SDavid Howells PTR_ERR(file), 491*1f08c925SDavid Howells cachefiles_trace_open_error); 492*1f08c925SDavid Howells goto out_dput; 493*1f08c925SDavid Howells } 494*1f08c925SDavid Howells if (unlikely(!file->f_op->read_iter) || 495*1f08c925SDavid Howells unlikely(!file->f_op->write_iter)) { 496*1f08c925SDavid Howells fput(file); 497*1f08c925SDavid Howells pr_notice("Cache does not support read_iter and write_iter\n"); 498*1f08c925SDavid Howells file = ERR_PTR(-EINVAL); 499*1f08c925SDavid Howells } 500*1f08c925SDavid Howells 501*1f08c925SDavid Howells out_dput: 502*1f08c925SDavid Howells dput(path.dentry); 503*1f08c925SDavid Howells out: 504*1f08c925SDavid Howells cachefiles_end_secure(cache, saved_cred); 505*1f08c925SDavid Howells return file; 506*1f08c925SDavid Howells } 507*1f08c925SDavid Howells 508*1f08c925SDavid Howells /* 509*1f08c925SDavid Howells * Create a new file. 510*1f08c925SDavid Howells */ 511*1f08c925SDavid Howells static bool cachefiles_create_file(struct cachefiles_object *object) 512*1f08c925SDavid Howells { 513*1f08c925SDavid Howells struct file *file; 514*1f08c925SDavid Howells int ret; 515*1f08c925SDavid Howells 516*1f08c925SDavid Howells ret = cachefiles_has_space(object->volume->cache, 1, 0); 517*1f08c925SDavid Howells if (ret < 0) 518*1f08c925SDavid Howells return false; 519*1f08c925SDavid Howells 520*1f08c925SDavid Howells file = cachefiles_create_tmpfile(object); 521*1f08c925SDavid Howells if (IS_ERR(file)) 522*1f08c925SDavid Howells return false; 523*1f08c925SDavid Howells 524*1f08c925SDavid Howells set_bit(FSCACHE_COOKIE_NEEDS_UPDATE, &object->cookie->flags); 525*1f08c925SDavid Howells set_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags); 526*1f08c925SDavid Howells _debug("create -> %pD{ino=%lu}", file, file_inode(file)->i_ino); 527*1f08c925SDavid Howells object->file = file; 528*1f08c925SDavid Howells return true; 529*1f08c925SDavid Howells } 530*1f08c925SDavid Howells 531*1f08c925SDavid Howells /* 532*1f08c925SDavid Howells * Open an existing file, checking its attributes and replacing it if it is 533*1f08c925SDavid Howells * stale. 534*1f08c925SDavid Howells */ 535*1f08c925SDavid Howells static bool cachefiles_open_file(struct cachefiles_object *object, 536*1f08c925SDavid Howells struct dentry *dentry) 537*1f08c925SDavid Howells { 538*1f08c925SDavid Howells struct cachefiles_cache *cache = object->volume->cache; 539*1f08c925SDavid Howells struct file *file; 540*1f08c925SDavid Howells struct path path; 541*1f08c925SDavid Howells int ret; 542*1f08c925SDavid Howells 543*1f08c925SDavid Howells _enter("%pd", dentry); 544*1f08c925SDavid Howells 545*1f08c925SDavid Howells if (!cachefiles_mark_inode_in_use(object, dentry)) 546*1f08c925SDavid Howells return false; 547*1f08c925SDavid Howells 548*1f08c925SDavid Howells /* We need to open a file interface onto a data file now as we can't do 549*1f08c925SDavid Howells * it on demand because writeback called from do_exit() sees 550*1f08c925SDavid Howells * current->fs == NULL - which breaks d_path() called from ext4 open. 551*1f08c925SDavid Howells */ 552*1f08c925SDavid Howells path.mnt = cache->mnt; 553*1f08c925SDavid Howells path.dentry = dentry; 554*1f08c925SDavid Howells file = open_with_fake_path(&path, O_RDWR | O_LARGEFILE | O_DIRECT, 555*1f08c925SDavid Howells d_backing_inode(dentry), cache->cache_cred); 556*1f08c925SDavid Howells if (IS_ERR(file)) { 557*1f08c925SDavid Howells trace_cachefiles_vfs_error(object, d_backing_inode(dentry), 558*1f08c925SDavid Howells PTR_ERR(file), 559*1f08c925SDavid Howells cachefiles_trace_open_error); 560*1f08c925SDavid Howells goto error; 561*1f08c925SDavid Howells } 562*1f08c925SDavid Howells 563*1f08c925SDavid Howells if (unlikely(!file->f_op->read_iter) || 564*1f08c925SDavid Howells unlikely(!file->f_op->write_iter)) { 565*1f08c925SDavid Howells pr_notice("Cache does not support read_iter and write_iter\n"); 566*1f08c925SDavid Howells goto error_fput; 567*1f08c925SDavid Howells } 568*1f08c925SDavid Howells _debug("file -> %pd positive", dentry); 569*1f08c925SDavid Howells 570*1f08c925SDavid Howells ret = cachefiles_check_auxdata(object, file); 571*1f08c925SDavid Howells if (ret < 0) 572*1f08c925SDavid Howells goto check_failed; 573*1f08c925SDavid Howells 574*1f08c925SDavid Howells object->file = file; 575*1f08c925SDavid Howells 576*1f08c925SDavid Howells /* Always update the atime on an object we've just looked up (this is 577*1f08c925SDavid Howells * used to keep track of culling, and atimes are only updated by read, 578*1f08c925SDavid Howells * write and readdir but not lookup or open). 579*1f08c925SDavid Howells */ 580*1f08c925SDavid Howells touch_atime(&file->f_path); 581*1f08c925SDavid Howells dput(dentry); 582*1f08c925SDavid Howells return true; 583*1f08c925SDavid Howells 584*1f08c925SDavid Howells check_failed: 585*1f08c925SDavid Howells fscache_cookie_lookup_negative(object->cookie); 586*1f08c925SDavid Howells cachefiles_unmark_inode_in_use(object, file); 587*1f08c925SDavid Howells if (ret == -ESTALE) { 588*1f08c925SDavid Howells fput(file); 589*1f08c925SDavid Howells dput(dentry); 590*1f08c925SDavid Howells return cachefiles_create_file(object); 591*1f08c925SDavid Howells } 592*1f08c925SDavid Howells error_fput: 593*1f08c925SDavid Howells fput(file); 594*1f08c925SDavid Howells error: 595*1f08c925SDavid Howells dput(dentry); 596*1f08c925SDavid Howells return false; 597*1f08c925SDavid Howells } 598*1f08c925SDavid Howells 599*1f08c925SDavid Howells /* 600*1f08c925SDavid Howells * walk from the parent object to the child object through the backing 601*1f08c925SDavid Howells * filesystem, creating directories as we go 602*1f08c925SDavid Howells */ 603*1f08c925SDavid Howells bool cachefiles_look_up_object(struct cachefiles_object *object) 604*1f08c925SDavid Howells { 605*1f08c925SDavid Howells struct cachefiles_volume *volume = object->volume; 606*1f08c925SDavid Howells struct dentry *dentry, *fan = volume->fanout[(u8)object->cookie->key_hash]; 607*1f08c925SDavid Howells int ret; 608*1f08c925SDavid Howells 609*1f08c925SDavid Howells _enter("OBJ%x,%s,", object->debug_id, object->d_name); 610*1f08c925SDavid Howells 611*1f08c925SDavid Howells /* Look up path "cache/vol/fanout/file". */ 612*1f08c925SDavid Howells ret = cachefiles_inject_read_error(); 613*1f08c925SDavid Howells if (ret == 0) 614*1f08c925SDavid Howells dentry = lookup_positive_unlocked(object->d_name, fan, 615*1f08c925SDavid Howells object->d_name_len); 616*1f08c925SDavid Howells else 617*1f08c925SDavid Howells dentry = ERR_PTR(ret); 618*1f08c925SDavid Howells trace_cachefiles_lookup(object, dentry); 619*1f08c925SDavid Howells if (IS_ERR(dentry)) { 620*1f08c925SDavid Howells if (dentry == ERR_PTR(-ENOENT)) 621*1f08c925SDavid Howells goto new_file; 622*1f08c925SDavid Howells if (dentry == ERR_PTR(-EIO)) 623*1f08c925SDavid Howells cachefiles_io_error_obj(object, "Lookup failed"); 624*1f08c925SDavid Howells return false; 625*1f08c925SDavid Howells } 626*1f08c925SDavid Howells 627*1f08c925SDavid Howells if (!d_is_reg(dentry)) { 628*1f08c925SDavid Howells pr_err("%pd is not a file\n", dentry); 629*1f08c925SDavid Howells inode_lock_nested(d_inode(fan), I_MUTEX_PARENT); 630*1f08c925SDavid Howells ret = cachefiles_bury_object(volume->cache, object, fan, dentry, 631*1f08c925SDavid Howells FSCACHE_OBJECT_IS_WEIRD); 632*1f08c925SDavid Howells dput(dentry); 633*1f08c925SDavid Howells if (ret < 0) 634*1f08c925SDavid Howells return false; 635*1f08c925SDavid Howells goto new_file; 636*1f08c925SDavid Howells } 637*1f08c925SDavid Howells 638*1f08c925SDavid Howells if (!cachefiles_open_file(object, dentry)) 639*1f08c925SDavid Howells return false; 640*1f08c925SDavid Howells 641*1f08c925SDavid Howells _leave(" = t [%lu]", file_inode(object->file)->i_ino); 642*1f08c925SDavid Howells return true; 643*1f08c925SDavid Howells 644*1f08c925SDavid Howells new_file: 645*1f08c925SDavid Howells fscache_cookie_lookup_negative(object->cookie); 646*1f08c925SDavid Howells return cachefiles_create_file(object); 647*1f08c925SDavid Howells } 648*1f08c925SDavid Howells 649*1f08c925SDavid Howells /* 650*1f08c925SDavid Howells * Attempt to link a temporary file into its rightful place in the cache. 651*1f08c925SDavid Howells */ 652*1f08c925SDavid Howells bool cachefiles_commit_tmpfile(struct cachefiles_cache *cache, 653*1f08c925SDavid Howells struct cachefiles_object *object) 654*1f08c925SDavid Howells { 655*1f08c925SDavid Howells struct cachefiles_volume *volume = object->volume; 656*1f08c925SDavid Howells struct dentry *dentry, *fan = volume->fanout[(u8)object->cookie->key_hash]; 657*1f08c925SDavid Howells bool success = false; 658*1f08c925SDavid Howells int ret; 659*1f08c925SDavid Howells 660*1f08c925SDavid Howells _enter(",%pD", object->file); 661*1f08c925SDavid Howells 662*1f08c925SDavid Howells inode_lock_nested(d_inode(fan), I_MUTEX_PARENT); 663*1f08c925SDavid Howells ret = cachefiles_inject_read_error(); 664*1f08c925SDavid Howells if (ret == 0) 665*1f08c925SDavid Howells dentry = lookup_one_len(object->d_name, fan, object->d_name_len); 666*1f08c925SDavid Howells else 667*1f08c925SDavid Howells dentry = ERR_PTR(ret); 668*1f08c925SDavid Howells if (IS_ERR(dentry)) { 669*1f08c925SDavid Howells trace_cachefiles_vfs_error(object, d_inode(fan), PTR_ERR(dentry), 670*1f08c925SDavid Howells cachefiles_trace_lookup_error); 671*1f08c925SDavid Howells _debug("lookup fail %ld", PTR_ERR(dentry)); 672*1f08c925SDavid Howells goto out_unlock; 673*1f08c925SDavid Howells } 674*1f08c925SDavid Howells 675*1f08c925SDavid Howells if (!d_is_negative(dentry)) { 676*1f08c925SDavid Howells if (d_backing_inode(dentry) == file_inode(object->file)) { 677*1f08c925SDavid Howells success = true; 678*1f08c925SDavid Howells goto out_dput; 679*1f08c925SDavid Howells } 680*1f08c925SDavid Howells 681*1f08c925SDavid Howells ret = cachefiles_unlink(volume->cache, object, fan, dentry, 682*1f08c925SDavid Howells FSCACHE_OBJECT_IS_STALE); 683*1f08c925SDavid Howells if (ret < 0) 684*1f08c925SDavid Howells goto out_dput; 685*1f08c925SDavid Howells 686*1f08c925SDavid Howells dput(dentry); 687*1f08c925SDavid Howells ret = cachefiles_inject_read_error(); 688*1f08c925SDavid Howells if (ret == 0) 689*1f08c925SDavid Howells dentry = lookup_one_len(object->d_name, fan, object->d_name_len); 690*1f08c925SDavid Howells else 691*1f08c925SDavid Howells dentry = ERR_PTR(ret); 692*1f08c925SDavid Howells if (IS_ERR(dentry)) { 693*1f08c925SDavid Howells trace_cachefiles_vfs_error(object, d_inode(fan), PTR_ERR(dentry), 694*1f08c925SDavid Howells cachefiles_trace_lookup_error); 695*1f08c925SDavid Howells _debug("lookup fail %ld", PTR_ERR(dentry)); 696*1f08c925SDavid Howells goto out_unlock; 697*1f08c925SDavid Howells } 698*1f08c925SDavid Howells } 699*1f08c925SDavid Howells 700*1f08c925SDavid Howells ret = cachefiles_inject_read_error(); 701*1f08c925SDavid Howells if (ret == 0) 702*1f08c925SDavid Howells ret = vfs_link(object->file->f_path.dentry, &init_user_ns, 703*1f08c925SDavid Howells d_inode(fan), dentry, NULL); 704*1f08c925SDavid Howells if (ret < 0) { 705*1f08c925SDavid Howells trace_cachefiles_vfs_error(object, d_inode(fan), ret, 706*1f08c925SDavid Howells cachefiles_trace_link_error); 707*1f08c925SDavid Howells _debug("link fail %d", ret); 708*1f08c925SDavid Howells } else { 709*1f08c925SDavid Howells trace_cachefiles_link(object, file_inode(object->file)); 710*1f08c925SDavid Howells spin_lock(&object->lock); 711*1f08c925SDavid Howells /* TODO: Do we want to switch the file pointer to the new dentry? */ 712*1f08c925SDavid Howells clear_bit(CACHEFILES_OBJECT_USING_TMPFILE, &object->flags); 713*1f08c925SDavid Howells spin_unlock(&object->lock); 714*1f08c925SDavid Howells success = true; 715*1f08c925SDavid Howells } 716*1f08c925SDavid Howells 717*1f08c925SDavid Howells out_dput: 718*1f08c925SDavid Howells dput(dentry); 719*1f08c925SDavid Howells out_unlock: 720*1f08c925SDavid Howells inode_unlock(d_inode(fan)); 721*1f08c925SDavid Howells _leave(" = %u", success); 722*1f08c925SDavid Howells return success; 723*1f08c925SDavid Howells } 724*1f08c925SDavid Howells 725*1f08c925SDavid Howells /* 72607a90e97SDavid Howells * Look up an inode to be checked or culled. Return -EBUSY if the inode is 72707a90e97SDavid Howells * marked in use. 72807a90e97SDavid Howells */ 72907a90e97SDavid Howells static struct dentry *cachefiles_lookup_for_cull(struct cachefiles_cache *cache, 73007a90e97SDavid Howells struct dentry *dir, 73107a90e97SDavid Howells char *filename) 73207a90e97SDavid Howells { 73307a90e97SDavid Howells struct dentry *victim; 73407a90e97SDavid Howells int ret = -ENOENT; 73507a90e97SDavid Howells 73607a90e97SDavid Howells inode_lock_nested(d_inode(dir), I_MUTEX_PARENT); 73707a90e97SDavid Howells 73807a90e97SDavid Howells victim = lookup_one_len(filename, dir, strlen(filename)); 73907a90e97SDavid Howells if (IS_ERR(victim)) 74007a90e97SDavid Howells goto lookup_error; 74107a90e97SDavid Howells if (d_is_negative(victim)) 74207a90e97SDavid Howells goto lookup_put; 74307a90e97SDavid Howells if (d_inode(victim)->i_flags & S_KERNEL_FILE) 74407a90e97SDavid Howells goto lookup_busy; 74507a90e97SDavid Howells return victim; 74607a90e97SDavid Howells 74707a90e97SDavid Howells lookup_busy: 74807a90e97SDavid Howells ret = -EBUSY; 74907a90e97SDavid Howells lookup_put: 75007a90e97SDavid Howells inode_unlock(d_inode(dir)); 75107a90e97SDavid Howells dput(victim); 75207a90e97SDavid Howells return ERR_PTR(ret); 75307a90e97SDavid Howells 75407a90e97SDavid Howells lookup_error: 75507a90e97SDavid Howells inode_unlock(d_inode(dir)); 75607a90e97SDavid Howells ret = PTR_ERR(victim); 75707a90e97SDavid Howells if (ret == -ENOENT) 75807a90e97SDavid Howells return ERR_PTR(-ESTALE); /* Probably got retired by the netfs */ 75907a90e97SDavid Howells 76007a90e97SDavid Howells if (ret == -EIO) { 76107a90e97SDavid Howells cachefiles_io_error(cache, "Lookup failed"); 76207a90e97SDavid Howells } else if (ret != -ENOMEM) { 76307a90e97SDavid Howells pr_err("Internal error: %d\n", ret); 76407a90e97SDavid Howells ret = -EIO; 76507a90e97SDavid Howells } 76607a90e97SDavid Howells 76707a90e97SDavid Howells return ERR_PTR(ret); 76807a90e97SDavid Howells } 76907a90e97SDavid Howells 77007a90e97SDavid Howells /* 77107a90e97SDavid Howells * Cull an object if it's not in use 77207a90e97SDavid Howells * - called only by cache manager daemon 77307a90e97SDavid Howells */ 77407a90e97SDavid Howells int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir, 77507a90e97SDavid Howells char *filename) 77607a90e97SDavid Howells { 77707a90e97SDavid Howells struct dentry *victim; 77807a90e97SDavid Howells struct inode *inode; 77907a90e97SDavid Howells int ret; 78007a90e97SDavid Howells 78107a90e97SDavid Howells _enter(",%pd/,%s", dir, filename); 78207a90e97SDavid Howells 78307a90e97SDavid Howells victim = cachefiles_lookup_for_cull(cache, dir, filename); 78407a90e97SDavid Howells if (IS_ERR(victim)) 78507a90e97SDavid Howells return PTR_ERR(victim); 78607a90e97SDavid Howells 78707a90e97SDavid Howells /* check to see if someone is using this object */ 78807a90e97SDavid Howells inode = d_inode(victim); 78907a90e97SDavid Howells inode_lock(inode); 79007a90e97SDavid Howells if (inode->i_flags & S_KERNEL_FILE) { 79107a90e97SDavid Howells ret = -EBUSY; 79207a90e97SDavid Howells } else { 79307a90e97SDavid Howells /* Stop the cache from picking it back up */ 79407a90e97SDavid Howells inode->i_flags |= S_KERNEL_FILE; 79507a90e97SDavid Howells ret = 0; 79607a90e97SDavid Howells } 79707a90e97SDavid Howells inode_unlock(inode); 79807a90e97SDavid Howells if (ret < 0) 79907a90e97SDavid Howells goto error_unlock; 80007a90e97SDavid Howells 80107a90e97SDavid Howells ret = cachefiles_bury_object(cache, NULL, dir, victim, 80207a90e97SDavid Howells FSCACHE_OBJECT_WAS_CULLED); 80307a90e97SDavid Howells if (ret < 0) 80407a90e97SDavid Howells goto error; 80507a90e97SDavid Howells 80607a90e97SDavid Howells dput(victim); 80707a90e97SDavid Howells _leave(" = 0"); 80807a90e97SDavid Howells return 0; 80907a90e97SDavid Howells 81007a90e97SDavid Howells error_unlock: 81107a90e97SDavid Howells inode_unlock(d_inode(dir)); 81207a90e97SDavid Howells error: 81307a90e97SDavid Howells dput(victim); 81407a90e97SDavid Howells if (ret == -ENOENT) 81507a90e97SDavid Howells return -ESTALE; /* Probably got retired by the netfs */ 81607a90e97SDavid Howells 81707a90e97SDavid Howells if (ret != -ENOMEM) { 81807a90e97SDavid Howells pr_err("Internal error: %d\n", ret); 81907a90e97SDavid Howells ret = -EIO; 82007a90e97SDavid Howells } 82107a90e97SDavid Howells 82207a90e97SDavid Howells _leave(" = %d", ret); 82307a90e97SDavid Howells return ret; 82407a90e97SDavid Howells } 82507a90e97SDavid Howells 82607a90e97SDavid Howells /* 82707a90e97SDavid Howells * Find out if an object is in use or not 82807a90e97SDavid Howells * - called only by cache manager daemon 82907a90e97SDavid Howells * - returns -EBUSY or 0 to indicate whether an object is in use or not 83007a90e97SDavid Howells */ 83107a90e97SDavid Howells int cachefiles_check_in_use(struct cachefiles_cache *cache, struct dentry *dir, 83207a90e97SDavid Howells char *filename) 83307a90e97SDavid Howells { 83407a90e97SDavid Howells struct dentry *victim; 83507a90e97SDavid Howells int ret = 0; 83607a90e97SDavid Howells 83707a90e97SDavid Howells victim = cachefiles_lookup_for_cull(cache, dir, filename); 83807a90e97SDavid Howells if (IS_ERR(victim)) 83907a90e97SDavid Howells return PTR_ERR(victim); 84007a90e97SDavid Howells 84107a90e97SDavid Howells inode_unlock(d_inode(dir)); 84207a90e97SDavid Howells dput(victim); 84307a90e97SDavid Howells return ret; 84407a90e97SDavid Howells } 845