diff options
Diffstat (limited to 'fs/cachefiles/interface.c')
| -rw-r--r-- | fs/cachefiles/interface.c | 572 |
1 files changed, 0 insertions, 572 deletions
diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c deleted file mode 100644 index da28ac1fa225..000000000000 --- a/fs/cachefiles/interface.c +++ /dev/null @@ -1,572 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* FS-Cache interface to CacheFiles - * - * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. - * Written by David Howells (dhowells@redhat.com) - */ - -#include <linux/slab.h> -#include <linux/mount.h> -#include "internal.h" - -struct cachefiles_lookup_data { - struct cachefiles_xattr *auxdata; /* auxiliary data */ - char *key; /* key path */ -}; - -static int cachefiles_attr_changed(struct fscache_object *_object); - -/* - * allocate an object record for a cookie lookup and prepare the lookup data - */ -static struct fscache_object *cachefiles_alloc_object( - struct fscache_cache *_cache, - struct fscache_cookie *cookie) -{ - struct cachefiles_lookup_data *lookup_data; - struct cachefiles_object *object; - struct cachefiles_cache *cache; - struct cachefiles_xattr *auxdata; - unsigned keylen, auxlen; - void *buffer, *p; - char *key; - - cache = container_of(_cache, struct cachefiles_cache, cache); - - _enter("{%s},%x,", cache->cache.identifier, cookie->debug_id); - - lookup_data = kmalloc(sizeof(*lookup_data), cachefiles_gfp); - if (!lookup_data) - goto nomem_lookup_data; - - /* create a new object record and a temporary leaf image */ - object = kmem_cache_alloc(cachefiles_object_jar, cachefiles_gfp); - if (!object) - goto nomem_object; - - ASSERTCMP(object->backer, ==, NULL); - - BUG_ON(test_bit(CACHEFILES_OBJECT_ACTIVE, &object->flags)); - atomic_set(&object->usage, 1); - - fscache_object_init(&object->fscache, cookie, &cache->cache); - - object->type = cookie->def->type; - - /* get hold of the raw key - * - stick the length on the front and leave space on the back for the - * encoder - */ - buffer = kmalloc((2 + 512) + 3, cachefiles_gfp); - if (!buffer) - goto nomem_buffer; - - keylen = cookie->key_len; - if (keylen <= sizeof(cookie->inline_key)) - p = cookie->inline_key; - else - p = cookie->key; - memcpy(buffer + 2, p, keylen); - - *(uint16_t *)buffer = keylen; - ((char *)buffer)[keylen + 2] = 0; - ((char *)buffer)[keylen + 3] = 0; - ((char *)buffer)[keylen + 4] = 0; - - /* turn the raw key into something that can work with as a filename */ - key = cachefiles_cook_key(buffer, keylen + 2, object->type); - if (!key) - goto nomem_key; - - /* get hold of the auxiliary data and prepend the object type */ - auxdata = buffer; - auxlen = cookie->aux_len; - if (auxlen) { - if (auxlen <= sizeof(cookie->inline_aux)) - p = cookie->inline_aux; - else - p = cookie->aux; - memcpy(auxdata->data, p, auxlen); - } - - auxdata->len = auxlen + 1; - auxdata->type = cookie->type; - - lookup_data->auxdata = auxdata; - lookup_data->key = key; - object->lookup_data = lookup_data; - - _leave(" = %x [%p]", object->fscache.debug_id, lookup_data); - return &object->fscache; - -nomem_key: - kfree(buffer); -nomem_buffer: - BUG_ON(test_bit(CACHEFILES_OBJECT_ACTIVE, &object->flags)); - kmem_cache_free(cachefiles_object_jar, object); - fscache_object_destroyed(&cache->cache); -nomem_object: - kfree(lookup_data); -nomem_lookup_data: - _leave(" = -ENOMEM"); - return ERR_PTR(-ENOMEM); -} - -/* - * attempt to look up the nominated node in this cache - * - return -ETIMEDOUT to be scheduled again - */ -static int cachefiles_lookup_object(struct fscache_object *_object) -{ - struct cachefiles_lookup_data *lookup_data; - struct cachefiles_object *parent, *object; - struct cachefiles_cache *cache; - const struct cred *saved_cred; - int ret; - - _enter("{OBJ%x}", _object->debug_id); - - cache = container_of(_object->cache, struct cachefiles_cache, cache); - parent = container_of(_object->parent, - struct cachefiles_object, fscache); - object = container_of(_object, struct cachefiles_object, fscache); - lookup_data = object->lookup_data; - - ASSERTCMP(lookup_data, !=, NULL); - - /* look up the key, creating any missing bits */ - cachefiles_begin_secure(cache, &saved_cred); - ret = cachefiles_walk_to_object(parent, object, - lookup_data->key, - lookup_data->auxdata); - cachefiles_end_secure(cache, saved_cred); - - /* polish off by setting the attributes of non-index files */ - if (ret == 0 && - object->fscache.cookie->def->type != FSCACHE_COOKIE_TYPE_INDEX) - cachefiles_attr_changed(&object->fscache); - - if (ret < 0 && ret != -ETIMEDOUT) { - if (ret != -ENOBUFS) - pr_warn("Lookup failed error %d\n", ret); - fscache_object_lookup_error(&object->fscache); - } - - _leave(" [%d]", ret); - return ret; -} - -/* - * indication of lookup completion - */ -static void cachefiles_lookup_complete(struct fscache_object *_object) -{ - struct cachefiles_object *object; - - object = container_of(_object, struct cachefiles_object, fscache); - - _enter("{OBJ%x,%p}", object->fscache.debug_id, object->lookup_data); - - if (object->lookup_data) { - kfree(object->lookup_data->key); - kfree(object->lookup_data->auxdata); - kfree(object->lookup_data); - object->lookup_data = NULL; - } -} - -/* - * increment the usage count on an inode object (may fail if unmounting) - */ -static -struct fscache_object *cachefiles_grab_object(struct fscache_object *_object, - enum fscache_obj_ref_trace why) -{ - struct cachefiles_object *object = - container_of(_object, struct cachefiles_object, fscache); - int u; - - _enter("{OBJ%x,%d}", _object->debug_id, atomic_read(&object->usage)); - -#ifdef CACHEFILES_DEBUG_SLAB - ASSERT((atomic_read(&object->usage) & 0xffff0000) != 0x6b6b0000); -#endif - - u = atomic_inc_return(&object->usage); - trace_cachefiles_ref(object, _object->cookie, - (enum cachefiles_obj_ref_trace)why, u); - return &object->fscache; -} - -/* - * update the auxiliary data for an object object on disk - */ -static void cachefiles_update_object(struct fscache_object *_object) -{ - struct cachefiles_object *object; - struct cachefiles_xattr *auxdata; - struct cachefiles_cache *cache; - struct fscache_cookie *cookie; - const struct cred *saved_cred; - const void *aux; - unsigned auxlen; - - _enter("{OBJ%x}", _object->debug_id); - - object = container_of(_object, struct cachefiles_object, fscache); - cache = container_of(object->fscache.cache, struct cachefiles_cache, - cache); - - if (!fscache_use_cookie(_object)) { - _leave(" [relinq]"); - return; - } - - cookie = object->fscache.cookie; - auxlen = cookie->aux_len; - - if (!auxlen) { - fscache_unuse_cookie(_object); - _leave(" [no aux]"); - return; - } - - auxdata = kmalloc(2 + auxlen + 3, cachefiles_gfp); - if (!auxdata) { - fscache_unuse_cookie(_object); - _leave(" [nomem]"); - return; - } - - aux = (auxlen <= sizeof(cookie->inline_aux)) ? - cookie->inline_aux : cookie->aux; - - memcpy(auxdata->data, aux, auxlen); - fscache_unuse_cookie(_object); - - auxdata->len = auxlen + 1; - auxdata->type = cookie->type; - - cachefiles_begin_secure(cache, &saved_cred); - cachefiles_update_object_xattr(object, auxdata); - cachefiles_end_secure(cache, saved_cred); - kfree(auxdata); - _leave(""); -} - -/* - * discard the resources pinned by an object and effect retirement if - * requested - */ -static void cachefiles_drop_object(struct fscache_object *_object) -{ - struct cachefiles_object *object; - struct cachefiles_cache *cache; - const struct cred *saved_cred; - struct inode *inode; - blkcnt_t i_blocks = 0; - - ASSERT(_object); - - object = container_of(_object, struct cachefiles_object, fscache); - - _enter("{OBJ%x,%d}", - object->fscache.debug_id, atomic_read(&object->usage)); - - cache = container_of(object->fscache.cache, - struct cachefiles_cache, cache); - -#ifdef CACHEFILES_DEBUG_SLAB - ASSERT((atomic_read(&object->usage) & 0xffff0000) != 0x6b6b0000); -#endif - - /* We need to tidy the object up if we did in fact manage to open it. - * It's possible for us to get here before the object is fully - * initialised if the parent goes away or the object gets retired - * before we set it up. - */ - if (object->dentry) { - /* delete retired objects */ - if (test_bit(FSCACHE_OBJECT_RETIRED, &object->fscache.flags) && - _object != cache->cache.fsdef - ) { - _debug("- retire object OBJ%x", object->fscache.debug_id); - inode = d_backing_inode(object->dentry); - if (inode) - i_blocks = inode->i_blocks; - - cachefiles_begin_secure(cache, &saved_cred); - cachefiles_delete_object(cache, object); - cachefiles_end_secure(cache, saved_cred); - } - - /* close the filesystem stuff attached to the object */ - if (object->backer != object->dentry) - dput(object->backer); - object->backer = NULL; - } - - /* note that the object is now inactive */ - if (test_bit(CACHEFILES_OBJECT_ACTIVE, &object->flags)) - cachefiles_mark_object_inactive(cache, object, i_blocks); - - dput(object->dentry); - object->dentry = NULL; - - _leave(""); -} - -/* - * dispose of a reference to an object - */ -void cachefiles_put_object(struct fscache_object *_object, - enum fscache_obj_ref_trace why) -{ - struct cachefiles_object *object; - struct fscache_cache *cache; - int u; - - ASSERT(_object); - - object = container_of(_object, struct cachefiles_object, fscache); - - _enter("{OBJ%x,%d}", - object->fscache.debug_id, atomic_read(&object->usage)); - -#ifdef CACHEFILES_DEBUG_SLAB - ASSERT((atomic_read(&object->usage) & 0xffff0000) != 0x6b6b0000); -#endif - - ASSERTIFCMP(object->fscache.parent, - object->fscache.parent->n_children, >, 0); - - u = atomic_dec_return(&object->usage); - trace_cachefiles_ref(object, _object->cookie, - (enum cachefiles_obj_ref_trace)why, u); - ASSERTCMP(u, !=, -1); - if (u == 0) { - _debug("- kill object OBJ%x", object->fscache.debug_id); - - ASSERT(!test_bit(CACHEFILES_OBJECT_ACTIVE, &object->flags)); - ASSERTCMP(object->fscache.parent, ==, NULL); - ASSERTCMP(object->backer, ==, NULL); - ASSERTCMP(object->dentry, ==, NULL); - ASSERTCMP(object->fscache.n_ops, ==, 0); - ASSERTCMP(object->fscache.n_children, ==, 0); - - if (object->lookup_data) { - kfree(object->lookup_data->key); - kfree(object->lookup_data->auxdata); - kfree(object->lookup_data); - object->lookup_data = NULL; - } - - cache = object->fscache.cache; - fscache_object_destroy(&object->fscache); - kmem_cache_free(cachefiles_object_jar, object); - fscache_object_destroyed(cache); - } - - _leave(""); -} - -/* - * sync a cache - */ -static void cachefiles_sync_cache(struct fscache_cache *_cache) -{ - struct cachefiles_cache *cache; - const struct cred *saved_cred; - int ret; - - _enter("%s", _cache->tag->name); - - cache = container_of(_cache, struct cachefiles_cache, cache); - - /* make sure all pages pinned by operations on behalf of the netfs are - * written to disc */ - cachefiles_begin_secure(cache, &saved_cred); - down_read(&cache->mnt->mnt_sb->s_umount); - ret = sync_filesystem(cache->mnt->mnt_sb); - up_read(&cache->mnt->mnt_sb->s_umount); - cachefiles_end_secure(cache, saved_cred); - - if (ret == -EIO) - cachefiles_io_error(cache, - "Attempt to sync backing fs superblock" - " returned error %d", - ret); -} - -/* - * check if the backing cache is updated to FS-Cache - * - called by FS-Cache when evaluates if need to invalidate the cache - */ -static int cachefiles_check_consistency(struct fscache_operation *op) -{ - struct cachefiles_object *object; - struct cachefiles_cache *cache; - const struct cred *saved_cred; - int ret; - - _enter("{OBJ%x}", op->object->debug_id); - - object = container_of(op->object, struct cachefiles_object, fscache); - cache = container_of(object->fscache.cache, - struct cachefiles_cache, cache); - - cachefiles_begin_secure(cache, &saved_cred); - ret = cachefiles_check_auxdata(object); - cachefiles_end_secure(cache, saved_cred); - - _leave(" = %d", ret); - return ret; -} - -/* - * notification the attributes on an object have changed - * - called with reads/writes excluded by FS-Cache - */ -static int cachefiles_attr_changed(struct fscache_object *_object) -{ - struct cachefiles_object *object; - struct cachefiles_cache *cache; - const struct cred *saved_cred; - struct iattr newattrs; - uint64_t ni_size; - loff_t oi_size; - int ret; - - ni_size = _object->store_limit_l; - - _enter("{OBJ%x},[%llu]", - _object->debug_id, (unsigned long long) ni_size); - - object = container_of(_object, struct cachefiles_object, fscache); - cache = container_of(object->fscache.cache, - struct cachefiles_cache, cache); - - if (ni_size == object->i_size) - return 0; - - if (!object->backer) - return -ENOBUFS; - - ASSERT(d_is_reg(object->backer)); - - fscache_set_store_limit(&object->fscache, ni_size); - - oi_size = i_size_read(d_backing_inode(object->backer)); - if (oi_size == ni_size) - return 0; - - cachefiles_begin_secure(cache, &saved_cred); - inode_lock(d_inode(object->backer)); - - /* if there's an extension to a partial page at the end of the backing - * file, we need to discard the partial page so that we pick up new - * data after it */ - if (oi_size & ~PAGE_MASK && ni_size > oi_size) { - _debug("discard tail %llx", oi_size); - newattrs.ia_valid = ATTR_SIZE; - newattrs.ia_size = oi_size & PAGE_MASK; - ret = notify_change(&init_user_ns, object->backer, &newattrs, NULL); - if (ret < 0) - goto truncate_failed; - } - - newattrs.ia_valid = ATTR_SIZE; - newattrs.ia_size = ni_size; - ret = notify_change(&init_user_ns, object->backer, &newattrs, NULL); - -truncate_failed: - inode_unlock(d_inode(object->backer)); - cachefiles_end_secure(cache, saved_cred); - - if (ret == -EIO) { - fscache_set_store_limit(&object->fscache, 0); - cachefiles_io_error_obj(object, "Size set failed"); - ret = -ENOBUFS; - } - - _leave(" = %d", ret); - return ret; -} - -/* - * Invalidate an object - */ -static void cachefiles_invalidate_object(struct fscache_operation *op) -{ - struct cachefiles_object *object; - struct cachefiles_cache *cache; - const struct cred *saved_cred; - struct path path; - uint64_t ni_size; - int ret; - - object = container_of(op->object, struct cachefiles_object, fscache); - cache = container_of(object->fscache.cache, - struct cachefiles_cache, cache); - - ni_size = op->object->store_limit_l; - - _enter("{OBJ%x},[%llu]", - op->object->debug_id, (unsigned long long)ni_size); - - if (object->backer) { - ASSERT(d_is_reg(object->backer)); - - fscache_set_store_limit(&object->fscache, ni_size); - - path.dentry = object->backer; - path.mnt = cache->mnt; - - cachefiles_begin_secure(cache, &saved_cred); - ret = vfs_truncate(&path, 0); - if (ret == 0) - ret = vfs_truncate(&path, ni_size); - cachefiles_end_secure(cache, saved_cred); - - if (ret != 0) { - fscache_set_store_limit(&object->fscache, 0); - if (ret == -EIO) - cachefiles_io_error_obj(object, - "Invalidate failed"); - } - } - - fscache_op_complete(op, true); - _leave(""); -} - -/* - * dissociate a cache from all the pages it was backing - */ -static void cachefiles_dissociate_pages(struct fscache_cache *cache) -{ - _enter(""); -} - -const struct fscache_cache_ops cachefiles_cache_ops = { - .name = "cachefiles", - .alloc_object = cachefiles_alloc_object, - .lookup_object = cachefiles_lookup_object, - .lookup_complete = cachefiles_lookup_complete, - .grab_object = cachefiles_grab_object, - .update_object = cachefiles_update_object, - .invalidate_object = cachefiles_invalidate_object, - .drop_object = cachefiles_drop_object, - .put_object = cachefiles_put_object, - .sync_cache = cachefiles_sync_cache, - .attr_changed = cachefiles_attr_changed, - .read_or_alloc_page = cachefiles_read_or_alloc_page, - .read_or_alloc_pages = cachefiles_read_or_alloc_pages, - .allocate_page = cachefiles_allocate_page, - .allocate_pages = cachefiles_allocate_pages, - .write_page = cachefiles_write_page, - .uncache_page = cachefiles_uncache_page, - .dissociate_pages = cachefiles_dissociate_pages, - .check_consistency = cachefiles_check_consistency, - .begin_read_operation = cachefiles_begin_read_operation, -}; 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