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-rw-r--r--fs/cachefiles/interface.c572
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,
-};