NFSv4: Ensure asynchronous open() calls always pin the mountpoint

A number of race conditions may currently ensue if the user presses ^C
and then unmounts the partition while an asynchronous open() is in
progress.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2007-06-05 12:30:00 -04:00
Родитель 539cd03a57
Коммит ad389da79f
2 изменённых файлов: 32 добавлений и 18 удалений

Просмотреть файл

@ -1244,7 +1244,7 @@ static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
attr.ia_mode = mode;
attr.ia_valid = ATTR_MODE;
if (nd && (nd->flags & LOOKUP_CREATE))
if ((nd->flags & LOOKUP_CREATE) != 0)
open_flags = nd->intent.open.flags;
lock_kernel();

Просмотреть файл

@ -221,7 +221,7 @@ struct nfs4_opendata {
struct nfs_open_confirmres c_res;
struct nfs_fattr f_attr;
struct nfs_fattr dir_attr;
struct dentry *dentry;
struct path path;
struct dentry *dir;
struct nfs4_state_owner *owner;
struct iattr attrs;
@ -230,11 +230,11 @@ struct nfs4_opendata {
int cancelled;
};
static struct nfs4_opendata *nfs4_opendata_alloc(struct dentry *dentry,
static struct nfs4_opendata *nfs4_opendata_alloc(struct path *path,
struct nfs4_state_owner *sp, int flags,
const struct iattr *attrs)
{
struct dentry *parent = dget_parent(dentry);
struct dentry *parent = dget_parent(path->dentry);
struct inode *dir = parent->d_inode;
struct nfs_server *server = NFS_SERVER(dir);
struct nfs4_opendata *p;
@ -246,7 +246,8 @@ static struct nfs4_opendata *nfs4_opendata_alloc(struct dentry *dentry,
if (p->o_arg.seqid == NULL)
goto err_free;
atomic_set(&p->count, 1);
p->dentry = dget(dentry);
p->path.mnt = mntget(path->mnt);
p->path.dentry = dget(path->dentry);
p->dir = parent;
p->owner = sp;
atomic_inc(&sp->so_count);
@ -254,7 +255,7 @@ static struct nfs4_opendata *nfs4_opendata_alloc(struct dentry *dentry,
p->o_arg.open_flags = flags,
p->o_arg.clientid = server->nfs_client->cl_clientid;
p->o_arg.id = sp->so_id;
p->o_arg.name = &dentry->d_name;
p->o_arg.name = &p->path.dentry->d_name;
p->o_arg.server = server;
p->o_arg.bitmask = server->attr_bitmask;
p->o_arg.claim = NFS4_OPEN_CLAIM_NULL;
@ -288,7 +289,8 @@ static void nfs4_opendata_free(struct nfs4_opendata *p)
nfs_free_seqid(p->o_arg.seqid);
nfs4_put_state_owner(p->owner);
dput(p->dir);
dput(p->dentry);
dput(p->path.dentry);
mntput(p->path.mnt);
kfree(p);
}
}
@ -478,7 +480,7 @@ static int _nfs4_do_open_reclaim(struct nfs_open_context *ctx, struct nfs4_state
}
delegation_type = delegation->type;
}
opendata = nfs4_opendata_alloc(ctx->path.dentry, state->owner, 0, NULL);
opendata = nfs4_opendata_alloc(&ctx->path, state->owner, 0, NULL);
if (opendata == NULL)
return -ENOMEM;
opendata->o_arg.claim = NFS4_OPEN_CLAIM_PREVIOUS;
@ -525,7 +527,7 @@ static int _nfs4_open_delegation_recall(struct nfs_open_context *ctx, struct nfs
if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
return 0;
opendata = nfs4_opendata_alloc(ctx->path.dentry, sp, 0, NULL);
opendata = nfs4_opendata_alloc(&ctx->path, sp, 0, NULL);
if (opendata == NULL)
return -ENOMEM;
opendata->o_arg.claim = NFS4_OPEN_CLAIM_DELEGATE_CUR;
@ -827,7 +829,7 @@ static int _nfs4_open_expired(struct nfs_open_context *ctx, struct nfs4_state *s
set_bit(NFS_DELEGATED_STATE, &state->flags);
return 0;
}
opendata = nfs4_opendata_alloc(ctx->path.dentry, state->owner, openflags, NULL);
opendata = nfs4_opendata_alloc(&ctx->path, state->owner, openflags, NULL);
if (opendata == NULL)
return -ENOMEM;
ret = nfs4_open_recover(opendata, state);
@ -955,7 +957,7 @@ static struct nfs4_state *nfs4_open_delegated(struct inode *inode, int flags, st
/*
* Returns a referenced nfs4_state
*/
static int _nfs4_do_open(struct inode *dir, struct dentry *dentry, int flags, struct iattr *sattr, struct rpc_cred *cred, struct nfs4_state **res)
static int _nfs4_do_open(struct inode *dir, struct path *path, int flags, struct iattr *sattr, struct rpc_cred *cred, struct nfs4_state **res)
{
struct nfs4_state_owner *sp;
struct nfs4_state *state = NULL;
@ -975,7 +977,7 @@ static int _nfs4_do_open(struct inode *dir, struct dentry *dentry, int flags, st
goto err_put_state_owner;
down_read(&clp->cl_sem);
status = -ENOMEM;
opendata = nfs4_opendata_alloc(dentry, sp, flags, sattr);
opendata = nfs4_opendata_alloc(path, sp, flags, sattr);
if (opendata == NULL)
goto err_release_rwsem;
@ -1006,14 +1008,14 @@ out_err:
}
static struct nfs4_state *nfs4_do_open(struct inode *dir, struct dentry *dentry, int flags, struct iattr *sattr, struct rpc_cred *cred)
static struct nfs4_state *nfs4_do_open(struct inode *dir, struct path *path, int flags, struct iattr *sattr, struct rpc_cred *cred)
{
struct nfs4_exception exception = { };
struct nfs4_state *res;
int status;
do {
status = _nfs4_do_open(dir, dentry, flags, sattr, cred, &res);
status = _nfs4_do_open(dir, path, flags, sattr, cred, &res);
if (status == 0)
break;
/* NOTE: BAD_SEQID means the server and client disagree about the
@ -1259,6 +1261,10 @@ static int nfs4_intent_set_file(struct nameidata *nd, struct dentry *dentry, str
struct dentry *
nfs4_atomic_open(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
{
struct path path = {
.mnt = nd->mnt,
.dentry = dentry,
};
struct iattr attr;
struct rpc_cred *cred;
struct nfs4_state *state;
@ -1277,7 +1283,7 @@ nfs4_atomic_open(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
cred = rpcauth_lookupcred(NFS_CLIENT(dir)->cl_auth, 0);
if (IS_ERR(cred))
return (struct dentry *)cred;
state = nfs4_do_open(dir, dentry, nd->intent.open.flags, &attr, cred);
state = nfs4_do_open(dir, &path, nd->intent.open.flags, &attr, cred);
put_rpccred(cred);
if (IS_ERR(state)) {
if (PTR_ERR(state) == -ENOENT)
@ -1294,6 +1300,10 @@ nfs4_atomic_open(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
int
nfs4_open_revalidate(struct inode *dir, struct dentry *dentry, int openflags, struct nameidata *nd)
{
struct path path = {
.mnt = nd->mnt,
.dentry = dentry,
};
struct rpc_cred *cred;
struct nfs4_state *state;
@ -1302,7 +1312,7 @@ nfs4_open_revalidate(struct inode *dir, struct dentry *dentry, int openflags, st
return PTR_ERR(cred);
state = nfs4_open_delegated(dentry->d_inode, openflags, cred);
if (IS_ERR(state))
state = nfs4_do_open(dir, dentry, openflags, NULL, cred);
state = nfs4_do_open(dir, &path, openflags, NULL, cred);
put_rpccred(cred);
if (IS_ERR(state)) {
switch (PTR_ERR(state)) {
@ -1752,6 +1762,10 @@ static int
nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
int flags, struct nameidata *nd)
{
struct path path = {
.mnt = nd->mnt,
.dentry = dentry,
};
struct nfs4_state *state;
struct rpc_cred *cred;
int status = 0;
@ -1761,7 +1775,7 @@ nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
status = PTR_ERR(cred);
goto out;
}
state = nfs4_do_open(dir, dentry, flags, sattr, cred);
state = nfs4_do_open(dir, &path, flags, sattr, cred);
put_rpccred(cred);
if (IS_ERR(state)) {
status = PTR_ERR(state);
@ -1774,7 +1788,7 @@ nfs4_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
if (status == 0)
nfs_setattr_update_inode(state->inode, sattr);
}
if (status == 0 && nd != NULL && (nd->flags & LOOKUP_OPEN))
if (status == 0 && (nd->flags & LOOKUP_OPEN) != 0)
status = nfs4_intent_set_file(nd, dentry, state);
else
nfs4_close_state(state, flags);