afs: Push the net ns pointer to more places

Push the network namespace pointer to more places in AFS, including the
afs_server structure (which doesn't hold a ref on the netns).

In particular, afs_put_cell() now takes requires a net ns parameter so that
it can safely alter the netns after decrementing the cell usage count - the
cell will be deallocated by a background thread after being cached for a
period, which means that it's not safe to access it after reducing its
usage count.

Signed-off-by: David Howells <dhowells@redhat.com>
This commit is contained in:
David Howells 2017-11-02 15:27:46 +00:00
parent 49566f6f06
commit 9ed900b116
11 changed files with 56 additions and 56 deletions

View File

@ -251,7 +251,7 @@ int afs_cell_init(struct afs_net *net, char *rootcell)
old_root = net->ws_cell;
net->ws_cell = new_root;
write_unlock(&net->cells_lock);
afs_put_cell(old_root);
afs_put_cell(net, old_root);
_leave(" = 0");
return 0;
@ -336,7 +336,7 @@ struct afs_cell *afs_get_cell_maybe(struct afs_cell *cell)
/*
* destroy a cell record
*/
void afs_put_cell(struct afs_cell *cell)
void afs_put_cell(struct afs_net *net, struct afs_cell *cell)
{
if (!cell)
return;
@ -347,10 +347,10 @@ void afs_put_cell(struct afs_cell *cell)
/* to prevent a race, the decrement and the dequeue must be effectively
* atomic */
write_lock(&cell->net->cells_lock);
write_lock(&net->cells_lock);
if (likely(!atomic_dec_and_test(&cell->usage))) {
write_unlock(&cell->net->cells_lock);
write_unlock(&net->cells_lock);
_leave("");
return;
}
@ -358,9 +358,9 @@ void afs_put_cell(struct afs_cell *cell)
ASSERT(list_empty(&cell->servers));
ASSERT(list_empty(&cell->vl_list));
wake_up(&cell->net->cells_freeable_wq);
wake_up(&net->cells_freeable_wq);
write_unlock(&cell->net->cells_lock);
write_unlock(&net->cells_lock);
_leave(" [unused]");
}
@ -424,7 +424,7 @@ void afs_cell_purge(struct afs_net *net)
_enter("");
afs_put_cell(net->ws_cell);
afs_put_cell(net, net->ws_cell);
down_write(&net->cells_sem);

View File

@ -151,7 +151,7 @@ static void afs_cm_destructor(struct afs_call *call)
afs_break_callbacks(call->server, call->count, call->request);
}
afs_put_server(call->server);
afs_put_server(call->net, call->server);
call->server = NULL;
kfree(call->buffer);
call->buffer = NULL;

View File

@ -771,7 +771,7 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
vnode->update_cnt++;
spin_unlock(&vnode->lock);
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
afs_put_server(afs_i2net(dir), server);
d_instantiate(dentry, inode);
if (d_unhashed(dentry)) {
@ -783,7 +783,7 @@ static int afs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
return 0;
iget_error:
afs_put_server(server);
afs_put_server(afs_i2net(dir), server);
mkdir_error:
key_put(key);
error:
@ -948,7 +948,7 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
vnode->update_cnt++;
spin_unlock(&vnode->lock);
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
afs_put_server(afs_i2net(dir), server);
d_instantiate(dentry, inode);
if (d_unhashed(dentry)) {
@ -960,7 +960,7 @@ static int afs_create(struct inode *dir, struct dentry *dentry, umode_t mode,
return 0;
iget_error:
afs_put_server(server);
afs_put_server(afs_i2net(dir), server);
create_error:
key_put(key);
error:
@ -1060,7 +1060,7 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry,
vnode->update_cnt++;
spin_unlock(&vnode->lock);
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
afs_put_server(afs_i2net(dir), server);
d_instantiate(dentry, inode);
if (d_unhashed(dentry)) {
@ -1072,7 +1072,7 @@ static int afs_symlink(struct inode *dir, struct dentry *dentry,
return 0;
iget_error:
afs_put_server(server);
afs_put_server(afs_i2net(dir), server);
create_error:
key_put(key);
error:

View File

@ -437,7 +437,7 @@ void afs_evict_inode(struct inode *inode)
spin_lock(&vnode->server->fs_lock);
rb_erase(&vnode->server_rb, &vnode->server->fs_vnodes);
spin_unlock(&vnode->server->fs_lock);
afs_put_server(vnode->server);
afs_put_server(afs_i2net(inode), vnode->server);
vnode->server = NULL;
}

View File

@ -335,6 +335,7 @@ struct afs_server {
atomic_t usage;
time64_t time_of_death; /* time at which put reduced usage to 0 */
struct in_addr addr; /* server address */
struct afs_net *net; /* Network namespace in which the server resides */
struct afs_cell *cell; /* cell in which server resides */
struct list_head link; /* link in cell's server list */
struct list_head grave; /* link in master graveyard list */
@ -513,7 +514,7 @@ extern int afs_cell_init(struct afs_net *, char *);
extern struct afs_cell *afs_cell_create(struct afs_net *, const char *, unsigned, char *, bool);
extern struct afs_cell *afs_cell_lookup(struct afs_net *, const char *, unsigned, bool);
extern struct afs_cell *afs_grab_cell(struct afs_cell *);
extern void afs_put_cell(struct afs_cell *);
extern void afs_put_cell(struct afs_net *, struct afs_cell *);
extern void __net_exit afs_cell_purge(struct afs_net *);
/*
@ -713,7 +714,7 @@ extern struct afs_server *afs_lookup_server(struct afs_cell *,
const struct in_addr *);
extern struct afs_server *afs_find_server(struct afs_net *,
const struct sockaddr_rxrpc *);
extern void afs_put_server(struct afs_server *);
extern void afs_put_server(struct afs_net *, struct afs_server *);
extern void afs_reap_server(struct work_struct *);
extern void __net_exit afs_purge_servers(struct afs_net *);
@ -802,7 +803,7 @@ static inline struct afs_volume *afs_get_volume(struct afs_volume *volume)
return volume;
}
extern void afs_put_volume(struct afs_net *, struct afs_volume *);
extern void afs_put_volume(struct afs_cell *, struct afs_volume *);
extern struct afs_volume *afs_volume_lookup(struct afs_mount_params *);
extern struct afs_server *afs_volume_pick_fileserver(struct afs_vnode *);
extern int afs_volume_release_fileserver(struct afs_vnode *,

View File

@ -285,7 +285,7 @@ static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
goto done;
}
afs_put_cell(cell);
afs_put_cell(net, cell);
printk("kAFS: Added new cell '%s'\n", name);
} else {
goto inval;

View File

@ -85,6 +85,7 @@ static struct afs_server *afs_alloc_server(struct afs_cell *cell,
server = kzalloc(sizeof(struct afs_server), GFP_KERNEL);
if (server) {
atomic_set(&server->usage, 1);
server->net = cell->net;
server->cell = cell;
INIT_LIST_HEAD(&server->link);
@ -245,10 +246,8 @@ static void afs_set_server_timer(struct afs_net *net, time64_t delay)
* destroy a server record
* - removes from the cell list
*/
void afs_put_server(struct afs_server *server)
void afs_put_server(struct afs_net *net, struct afs_server *server)
{
struct afs_net *net = server->cell->net;
if (!server)
return;
@ -290,7 +289,7 @@ static void afs_destroy_server(struct afs_net *net, struct afs_server *server)
ASSERTCMP(server->cb_break_head, ==, server->cb_break_tail);
ASSERTCMP(atomic_read(&server->cb_break_n), ==, 0);
afs_put_cell(server->cell);
afs_put_cell(server->net, server->cell);
kfree(server);
afs_dec_servers_outstanding(net);
}

View File

@ -206,7 +206,7 @@ static int afs_parse_options(struct afs_mount_params *params,
false);
if (IS_ERR(cell))
return PTR_ERR(cell);
afs_put_cell(params->cell);
afs_put_cell(params->net, params->cell);
params->cell = cell;
break;
@ -314,7 +314,7 @@ static int afs_parse_device_name(struct afs_mount_params *params,
cellnamesz, cellnamesz, cellname ?: "");
return PTR_ERR(cell);
}
afs_put_cell(params->cell);
afs_put_cell(params->net, params->cell);
params->cell = cell;
}
@ -409,8 +409,8 @@ static struct afs_super_info *afs_alloc_sbi(struct afs_mount_params *params)
static void afs_destroy_sbi(struct afs_super_info *as)
{
if (as) {
afs_put_volume(as->net, as->volume);
afs_put_cell(as->cell);
afs_put_volume(as->cell, as->volume);
afs_put_cell(as->net, as->cell);
afs_put_net(as->net);
kfree(as);
}
@ -494,7 +494,7 @@ static struct dentry *afs_mount(struct file_system_type *fs_type,
as = NULL;
}
afs_put_cell(params.cell);
afs_put_cell(params.net, params.cell);
key_put(params.key);
_leave(" = 0 [%p]", sb);
return dget(sb->s_root);
@ -504,7 +504,7 @@ error_sb:
error_as:
afs_destroy_sbi(as);
error:
afs_put_cell(params.cell);
afs_put_cell(params.net, params.cell);
key_put(params.key);
_leave(" = %d", ret);
return ERR_PTR(ret);

View File

@ -518,14 +518,14 @@ void afs_put_vlocation(struct afs_net *net, struct afs_vlocation *vl)
/*
* destroy a dead volume location record
*/
static void afs_vlocation_destroy(struct afs_vlocation *vl)
static void afs_vlocation_destroy(struct afs_net *net, struct afs_vlocation *vl)
{
_enter("%p", vl);
#ifdef CONFIG_AFS_FSCACHE
fscache_relinquish_cookie(vl->cache, 0);
#endif
afs_put_cell(vl->cell);
afs_put_cell(net, vl->cell);
kfree(vl);
}
@ -580,7 +580,7 @@ void afs_vlocation_reaper(struct work_struct *work)
while (!list_empty(&corpses)) {
vl = list_entry(corpses.next, struct afs_vlocation, grave);
list_del(&vl->grave);
afs_vlocation_destroy(vl);
afs_vlocation_destroy(net, vl);
}
_leave("");

View File

@ -73,7 +73,7 @@ static void afs_install_vnode(struct afs_vnode *vnode,
afs_get_server(server);
vnode->server = server;
afs_put_server(old_server);
afs_put_server(afs_v2net(vnode), old_server);
/* insert into the server's vnode tree in FID order */
spin_lock(&server->fs_lock);
@ -196,7 +196,7 @@ static void afs_vnode_deleted_remotely(struct afs_vnode *vnode)
spin_unlock(&server->fs_lock);
vnode->server = NULL;
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
} else {
ASSERT(!vnode->cb_promised);
}
@ -225,7 +225,7 @@ void afs_vnode_finalise_status_update(struct afs_vnode *vnode,
spin_unlock(&vnode->lock);
wake_up_all(&vnode->update_waitq);
afs_put_server(oldserver);
afs_put_server(afs_v2net(vnode), oldserver);
_leave("");
}
@ -368,7 +368,7 @@ get_anyway:
if (auth_vnode)
afs_cache_permit(vnode, key, acl_order);
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
} else {
_debug("failed [%d]", ret);
afs_vnode_status_update_failed(vnode, ret);
@ -428,7 +428,7 @@ int afs_vnode_fetch_data(struct afs_vnode *vnode, struct key *key,
/* adjust the flags */
if (ret == 0) {
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
} else {
afs_vnode_status_update_failed(vnode, ret);
}
@ -540,7 +540,7 @@ int afs_vnode_remove(struct afs_vnode *vnode, struct key *key, const char *name,
/* adjust the flags */
if (ret == 0) {
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
} else {
afs_vnode_status_update_failed(vnode, ret);
}
@ -603,7 +603,7 @@ int afs_vnode_link(struct afs_vnode *dvnode, struct afs_vnode *vnode,
if (ret == 0) {
afs_vnode_finalise_status_update(vnode, server);
afs_vnode_finalise_status_update(dvnode, server);
afs_put_server(server);
afs_put_server(afs_v2net(dvnode), server);
} else {
afs_vnode_status_update_failed(vnode, ret);
afs_vnode_status_update_failed(dvnode, ret);
@ -738,7 +738,7 @@ int afs_vnode_rename(struct afs_vnode *orig_dvnode,
afs_vnode_finalise_status_update(orig_dvnode, server);
if (new_dvnode != orig_dvnode)
afs_vnode_finalise_status_update(new_dvnode, server);
afs_put_server(server);
afs_put_server(afs_v2net(orig_dvnode), server);
} else {
afs_vnode_status_update_failed(orig_dvnode, ret);
if (new_dvnode != orig_dvnode)
@ -802,7 +802,7 @@ int afs_vnode_store_data(struct afs_writeback *wb, pgoff_t first, pgoff_t last,
/* adjust the flags */
if (ret == 0) {
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
} else {
afs_vnode_status_update_failed(vnode, ret);
}
@ -854,7 +854,7 @@ int afs_vnode_setattr(struct afs_vnode *vnode, struct key *key,
/* adjust the flags */
if (ret == 0) {
afs_vnode_finalise_status_update(vnode, server);
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
} else {
afs_vnode_status_update_failed(vnode, ret);
}
@ -900,7 +900,7 @@ int afs_vnode_get_volume_status(struct afs_vnode *vnode, struct key *key,
/* adjust the flags */
if (ret == 0)
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
_leave(" = %d", ret);
return ret;
@ -939,7 +939,7 @@ int afs_vnode_set_lock(struct afs_vnode *vnode, struct key *key,
/* adjust the flags */
if (ret == 0)
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
_leave(" = %d", ret);
return ret;
@ -977,7 +977,7 @@ int afs_vnode_extend_lock(struct afs_vnode *vnode, struct key *key)
/* adjust the flags */
if (ret == 0)
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
_leave(" = %d", ret);
return ret;
@ -1015,7 +1015,7 @@ int afs_vnode_release_lock(struct afs_vnode *vnode, struct key *key)
/* adjust the flags */
if (ret == 0)
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
_leave(" = %d", ret);
return ret;

View File

@ -154,7 +154,7 @@ error_discard:
up_write(&params->cell->vl_sem);
for (loop = volume->nservers - 1; loop >= 0; loop--)
afs_put_server(volume->servers[loop]);
afs_put_server(params->net, volume->servers[loop]);
kfree(volume);
goto error;
@ -163,7 +163,7 @@ error_discard:
/*
* destroy a volume record
*/
void afs_put_volume(struct afs_net *net, struct afs_volume *volume)
void afs_put_volume(struct afs_cell *cell, struct afs_volume *volume)
{
struct afs_vlocation *vlocation;
int loop;
@ -179,7 +179,7 @@ void afs_put_volume(struct afs_net *net, struct afs_volume *volume)
/* to prevent a race, the decrement and the dequeue must be effectively
* atomic */
down_write(&vlocation->cell->vl_sem);
down_write(&cell->vl_sem);
if (likely(!atomic_dec_and_test(&volume->usage))) {
up_write(&vlocation->cell->vl_sem);
@ -189,16 +189,16 @@ void afs_put_volume(struct afs_net *net, struct afs_volume *volume)
vlocation->vols[volume->type] = NULL;
up_write(&vlocation->cell->vl_sem);
up_write(&cell->vl_sem);
/* finish cleaning up the volume */
#ifdef CONFIG_AFS_FSCACHE
fscache_relinquish_cookie(volume->cache, 0);
#endif
afs_put_vlocation(net, vlocation);
afs_put_vlocation(cell->net, vlocation);
for (loop = volume->nservers - 1; loop >= 0; loop--)
afs_put_server(volume->servers[loop]);
afs_put_server(cell->net, volume->servers[loop]);
kfree(volume);
@ -336,7 +336,7 @@ int afs_volume_release_fileserver(struct afs_vnode *vnode,
sizeof(volume->servers[loop]) *
(volume->nservers - loop));
volume->servers[volume->nservers] = NULL;
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
volume->rjservers++;
if (volume->nservers > 0)
@ -350,7 +350,7 @@ int afs_volume_release_fileserver(struct afs_vnode *vnode,
* no longer registered
*/
up_write(&volume->server_sem);
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
_leave(" [completely rejected]");
return 1;
@ -379,7 +379,7 @@ int afs_volume_release_fileserver(struct afs_vnode *vnode,
case -ENOMEM:
case -ENONET:
/* tell the caller to accept the result */
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
_leave(" [local failure]");
return 1;
}
@ -388,7 +388,7 @@ int afs_volume_release_fileserver(struct afs_vnode *vnode,
try_next_server_upw:
up_write(&volume->server_sem);
try_next_server:
afs_put_server(server);
afs_put_server(afs_v2net(vnode), server);
_leave(" [try next server]");
return 0;
}