From e4eff1a622edd6ab7b73acd5d8763aa2fa3fee49 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sat, 14 Jul 2007 15:39:58 -0400 Subject: SUNRPC: Clean up the sillyrename code Fix a couple of bugs: - Don't rely on the parent dentry still being valid when the call completes. Fixes a race with shrink_dcache_for_umount_subtree() - Don't remove the file if the filehandle has been labelled as stale. Fix a couple of inefficiencies - Remove the global list of sillyrenamed files. Instead we can cache the sillyrename information in the dentry->d_fsdata - Move common code from unlink_setup/unlink_done into fs/nfs/unlink.c Signed-off-by: Trond Myklebust --- fs/nfs/unlink.c | 195 +++++++++++++++++++++++++------------------------------- 1 file changed, 86 insertions(+), 109 deletions(-) (limited to 'fs/nfs/unlink.c') diff --git a/fs/nfs/unlink.c b/fs/nfs/unlink.c index 0e28189c2151..045ab805c17f 100644 --- a/fs/nfs/unlink.c +++ b/fs/nfs/unlink.c @@ -3,7 +3,6 @@ * * nfs sillydelete handling * - * NOTE: we rely on holding the BKL for list manipulation protection. */ #include @@ -15,46 +14,23 @@ struct nfs_unlinkdata { - struct nfs_unlinkdata *next; - struct dentry *dir, *dentry; - struct qstr name; - struct rpc_task task; + struct nfs_removeargs args; + struct nfs_removeres res; + struct inode *dir; struct rpc_cred *cred; - unsigned int count; }; -static struct nfs_unlinkdata *nfs_deletes; -static RPC_WAITQ(nfs_delete_queue, "nfs_delete_queue"); - -/** - * nfs_detach_unlinkdata - Remove asynchronous unlink from global list - * @data: pointer to descriptor - */ -static inline void -nfs_detach_unlinkdata(struct nfs_unlinkdata *data) -{ - struct nfs_unlinkdata **q; - - for (q = &nfs_deletes; *q != NULL; q = &((*q)->next)) { - if (*q == data) { - *q = data->next; - break; - } - } -} - /** - * nfs_put_unlinkdata - release data from a sillydelete operation. + * nfs_free_unlinkdata - release data from a sillydelete operation. * @data: pointer to unlink structure. */ static void -nfs_put_unlinkdata(struct nfs_unlinkdata *data) +nfs_free_unlinkdata(struct nfs_unlinkdata *data) { - if (--data->count == 0) { - nfs_detach_unlinkdata(data); - kfree(data->name.name); - kfree(data); - } + iput(data->dir); + put_rpccred(data->cred); + kfree(data->args.name.name); + kfree(data); } #define NAME_ALLOC_LEN(len) ((len+16) & ~15) @@ -63,50 +39,36 @@ nfs_put_unlinkdata(struct nfs_unlinkdata *data) * @dentry: pointer to dentry * @data: nfs_unlinkdata */ -static inline void -nfs_copy_dname(struct dentry *dentry, struct nfs_unlinkdata *data) +static int nfs_copy_dname(struct dentry *dentry, struct nfs_unlinkdata *data) { char *str; int len = dentry->d_name.len; - str = kmalloc(NAME_ALLOC_LEN(len), GFP_KERNEL); + str = kmemdup(dentry->d_name.name, NAME_ALLOC_LEN(len), GFP_KERNEL); if (!str) - return; - memcpy(str, dentry->d_name.name, len); - if (!data->name.len) { - data->name.len = len; - data->name.name = str; - } else - kfree(str); + return -ENOMEM; + data->args.name.len = len; + data->args.name.name = str; + return 0; } /** * nfs_async_unlink_init - Initialize the RPC info - * @task: rpc_task of the sillydelete - * - * We delay initializing RPC info until after the call to dentry_iput() - * in order to minimize races against rename(). + * task: rpc_task of the sillydelete */ static void nfs_async_unlink_init(struct rpc_task *task, void *calldata) { - struct nfs_unlinkdata *data = calldata; - struct dentry *dir = data->dir; - struct rpc_message msg = { - .rpc_cred = data->cred, + struct nfs_unlinkdata *data = calldata; + struct inode *dir = data->dir; + struct rpc_message msg = { + .rpc_argp = &data->args, + .rpc_resp = &data->res, + .rpc_cred = data->cred, }; - int status = -ENOENT; - - if (!data->name.len) - goto out_err; - status = NFS_PROTO(dir->d_inode)->unlink_setup(&msg, dir, &data->name); - if (status < 0) - goto out_err; - nfs_begin_data_update(dir->d_inode); + nfs_begin_data_update(dir); + NFS_PROTO(dir)->unlink_setup(&msg, dir); rpc_call_setup(task, &msg, 0); - return; - out_err: - rpc_exit(task, status); } /** @@ -117,19 +79,13 @@ static void nfs_async_unlink_init(struct rpc_task *task, void *calldata) */ static void nfs_async_unlink_done(struct rpc_task *task, void *calldata) { - struct nfs_unlinkdata *data = calldata; - struct dentry *dir = data->dir; - struct inode *dir_i; - - if (!dir) - return; - dir_i = dir->d_inode; - nfs_end_data_update(dir_i); - if (NFS_PROTO(dir_i)->unlink_done(dir, task)) - return; - put_rpccred(data->cred); - data->cred = NULL; - dput(dir); + struct nfs_unlinkdata *data = calldata; + struct inode *dir = data->dir; + + if (!NFS_PROTO(dir)->unlink_done(task, dir)) + rpc_restart_call(task); + else + nfs_end_data_update(dir); } /** @@ -142,7 +98,7 @@ static void nfs_async_unlink_done(struct rpc_task *task, void *calldata) static void nfs_async_unlink_release(void *calldata) { struct nfs_unlinkdata *data = calldata; - nfs_put_unlinkdata(data); + nfs_free_unlinkdata(data); } static const struct rpc_call_ops nfs_unlink_ops = { @@ -151,73 +107,94 @@ static const struct rpc_call_ops nfs_unlink_ops = { .rpc_release = nfs_async_unlink_release, }; +static int nfs_call_unlink(struct dentry *dentry, struct nfs_unlinkdata *data) +{ + struct rpc_task *task; + struct dentry *parent; + struct inode *dir; + + if (nfs_copy_dname(dentry, data) < 0) + goto out_free; + + parent = dget_parent(dentry); + if (parent == NULL) + goto out_free; + dir = igrab(parent->d_inode); + dput(parent); + if (dir == NULL) + goto out_free; + + data->dir = dir; + data->args.fh = NFS_FH(dir); + nfs_fattr_init(&data->res.dir_attr); + + task = rpc_run_task(NFS_CLIENT(dir), RPC_TASK_ASYNC, &nfs_unlink_ops, data); + if (!IS_ERR(task)) + rpc_put_task(task); + return 1; +out_free: + return 0; +} + /** * nfs_async_unlink - asynchronous unlinking of a file + * @dir: parent directory of dentry * @dentry: dentry to unlink */ int -nfs_async_unlink(struct dentry *dentry) +nfs_async_unlink(struct inode *dir, struct dentry *dentry) { - struct dentry *dir = dentry->d_parent; - struct nfs_unlinkdata *data; - struct rpc_clnt *clnt = NFS_CLIENT(dir->d_inode); - int status = -ENOMEM; + struct nfs_unlinkdata *data; + int status = -ENOMEM; data = kzalloc(sizeof(*data), GFP_KERNEL); - if (!data) + if (data == NULL) goto out; - data->cred = rpcauth_lookupcred(clnt->cl_auth, 0); + data->cred = rpcauth_lookupcred(NFS_CLIENT(dir)->cl_auth, 0); if (IS_ERR(data->cred)) { status = PTR_ERR(data->cred); goto out_free; } - data->dir = dget(dir); - data->dentry = dentry; - - data->next = nfs_deletes; - nfs_deletes = data; - data->count = 1; - - rpc_init_task(&data->task, clnt, RPC_TASK_ASYNC, &nfs_unlink_ops, data); + status = -EBUSY; spin_lock(&dentry->d_lock); + if (dentry->d_flags & DCACHE_NFSFS_RENAMED) + goto out_unlock; dentry->d_flags |= DCACHE_NFSFS_RENAMED; + dentry->d_fsdata = data; spin_unlock(&dentry->d_lock); - - rpc_sleep_on(&nfs_delete_queue, &data->task, NULL, NULL); - status = 0; - out: - return status; + return 0; +out_unlock: + spin_unlock(&dentry->d_lock); + put_rpccred(data->cred); out_free: kfree(data); +out: return status; } /** * nfs_complete_unlink - Initialize completion of the sillydelete * @dentry: dentry to delete + * @inode: inode * * Since we're most likely to be called by dentry_iput(), we * only use the dentry to find the sillydelete. We then copy the name * into the qstr. */ void -nfs_complete_unlink(struct dentry *dentry) +nfs_complete_unlink(struct dentry *dentry, struct inode *inode) { - struct nfs_unlinkdata *data; + struct nfs_unlinkdata *data = NULL; - for(data = nfs_deletes; data != NULL; data = data->next) { - if (dentry == data->dentry) - break; - } - if (!data) - return; - data->count++; - nfs_copy_dname(dentry, data); spin_lock(&dentry->d_lock); - dentry->d_flags &= ~DCACHE_NFSFS_RENAMED; + if (dentry->d_flags & DCACHE_NFSFS_RENAMED) { + dentry->d_flags &= ~DCACHE_NFSFS_RENAMED; + data = dentry->d_fsdata; + } spin_unlock(&dentry->d_lock); - rpc_wake_up_task(&data->task); - nfs_put_unlinkdata(data); + + if (data != NULL && (NFS_STALE(inode) || !nfs_call_unlink(dentry, data))) + nfs_free_unlinkdata(data); } -- cgit v1.2.3