const struct file_operations nfs_dir_operations = {
.llseek = nfs_llseek_dir,
.read = generic_read_dir,
- .iterate = nfs_readdir,
+ .iterate_shared = nfs_readdir,
.open = nfs_opendir,
.release = nfs_closedir,
.fsync = nfs_fsync_dir,
loff_t current_index;
decode_dirent_t decode;
+ unsigned long dir_verifier;
unsigned long timestamp;
unsigned long gencount;
unsigned int cache_entry_index;
bool eof;
} nfs_readdir_descriptor_t;
+static
+void nfs_readdir_init_array(struct page *page)
+{
+ struct nfs_cache_array *array;
+
+ array = kmap_atomic(page);
+ memset(array, 0, sizeof(struct nfs_cache_array));
+ array->eof_index = -1;
+ kunmap_atomic(array);
+}
+
/*
* we are freeing strings created by nfs_add_to_readdir_array()
*/
array = kmap_atomic(page);
for (i = 0; i < array->size; i++)
kfree(array->array[i].string.name);
+ array->size = 0;
kunmap_atomic(array);
}
int nfs_readdir_make_qstr(struct qstr *string, const char *name, unsigned int len)
{
string->len = len;
- string->name = kmemdup(name, len, GFP_KERNEL);
+ string->name = kmemdup_nul(name, len, GFP_KERNEL);
if (string->name == NULL)
return -ENOMEM;
/*
again:
timestamp = jiffies;
gencount = nfs_inc_attr_generation_counter();
+ desc->dir_verifier = nfs_save_change_attribute(inode);
error = NFS_PROTO(inode)->readdir(file_dentry(file), cred, entry->cookie, pages,
NFS_SERVER(inode)->dtsize, desc->plus);
if (error < 0) {
if (nfs_server_capable(dir, NFS_CAP_READDIRPLUS) &&
!list_empty(&nfsi->open_files)) {
set_bit(NFS_INO_ADVISE_RDPLUS, &nfsi->flags);
- invalidate_mapping_pages(dir->i_mapping, 0, -1);
+ invalidate_mapping_pages(dir->i_mapping,
+ nfsi->page_index + 1, -1);
}
}
static
-void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
+void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry,
+ unsigned long dir_verifier)
{
struct qstr filename = QSTR_INIT(entry->name, entry->len);
DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
struct dentry *dentry;
struct dentry *alias;
- struct inode *dir = d_inode(parent);
struct inode *inode;
int status;
if (nfs_same_file(dentry, entry)) {
if (!entry->fh->size)
goto out;
- nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
+ nfs_set_verifier(dentry, dir_verifier);
status = nfs_refresh_inode(d_inode(dentry), entry->fattr);
if (!status)
nfs_setsecurity(d_inode(dentry), entry->fattr, entry->label);
dput(dentry);
dentry = alias;
}
- nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
+ nfs_set_verifier(dentry, dir_verifier);
out:
dput(dentry);
}
count++;
if (desc->plus)
- nfs_prime_dcache(file_dentry(desc->file), entry);
+ nfs_prime_dcache(file_dentry(desc->file), entry,
+ desc->dir_verifier);
status = nfs_readdir_add_to_array(entry, page);
if (status != 0)
int status = -ENOMEM;
unsigned int array_size = ARRAY_SIZE(pages);
+ nfs_readdir_init_array(page);
+
entry.prev_cookie = 0;
entry.cookie = desc->last_cookie;
entry.eof = 0;
}
array = kmap(page);
- memset(array, 0, sizeof(struct nfs_cache_array));
- array->eof_index = -1;
status = nfs_readdir_alloc_pages(pages, array_size);
if (status < 0)
unlock_page(page);
return 0;
error:
+ nfs_readdir_clear_array(page);
unlock_page(page);
return ret;
}
static
void cache_page_release(nfs_readdir_descriptor_t *desc)
{
- if (!desc->page->mapping)
- nfs_readdir_clear_array(desc->page);
put_page(desc->page);
desc->page = NULL;
}
/*
* Returns 0 if desc->dir_cookie was found on page desc->page_index
+ * and locks the page to prevent removal from the page cache.
*/
static
-int find_cache_page(nfs_readdir_descriptor_t *desc)
+int find_and_lock_cache_page(nfs_readdir_descriptor_t *desc)
{
+ struct inode *inode = file_inode(desc->file);
+ struct nfs_inode *nfsi = NFS_I(inode);
int res;
desc->page = get_cache_page(desc);
if (IS_ERR(desc->page))
return PTR_ERR(desc->page);
-
- res = nfs_readdir_search_array(desc);
+ res = lock_page_killable(desc->page);
if (res != 0)
- cache_page_release(desc);
+ goto error;
+ res = -EAGAIN;
+ if (desc->page->mapping != NULL) {
+ res = nfs_readdir_search_array(desc);
+ if (res == 0) {
+ nfsi->page_index = desc->page_index;
+ return 0;
+ }
+ }
+ unlock_page(desc->page);
+error:
+ cache_page_release(desc);
return res;
}
desc->last_cookie = 0;
}
do {
- res = find_cache_page(desc);
+ res = find_and_lock_cache_page(desc);
} while (res == -EAGAIN);
return res;
}
desc->eof = true;
kunmap(desc->page);
- cache_page_release(desc);
dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
(unsigned long long)*desc->dir_cookie, res);
return res;
status = nfs_do_filldir(desc);
+ out_release:
+ nfs_readdir_clear_array(desc->page);
+ cache_page_release(desc);
out:
dfprintk(DIRCACHE, "NFS: %s: returns %d\n",
__func__, status);
return status;
- out_release:
- cache_page_release(desc);
- goto out;
}
/* The file offset position represents the dirent entry number. A
break;
res = nfs_do_filldir(desc);
+ unlock_page(desc->page);
+ cache_page_release(desc);
if (res < 0)
break;
} while (!desc->eof);
* full lookup on all child dentries of 'dir' whenever a change occurs
* on the server that might have invalidated our dcache.
*
+ * Note that we reserve bit '0' as a tag to let us know when a dentry
+ * was revalidated while holding a delegation on its inode.
+ *
* The caller should be holding dir->i_lock
*/
void nfs_force_lookup_revalidate(struct inode *dir)
{
- NFS_I(dir)->cache_change_attribute++;
+ NFS_I(dir)->cache_change_attribute += 2;
}
EXPORT_SYMBOL_GPL(nfs_force_lookup_revalidate);
+/**
+ * nfs_verify_change_attribute - Detects NFS remote directory changes
+ * @dir: pointer to parent directory inode
+ * @verf: previously saved change attribute
+ *
+ * Return "false" if the verifiers doesn't match the change attribute.
+ * This would usually indicate that the directory contents have changed on
+ * the server, and that any dentries need revalidating.
+ */
+static bool nfs_verify_change_attribute(struct inode *dir, unsigned long verf)
+{
+ return (verf & ~1UL) == nfs_save_change_attribute(dir);
+}
+
+static void nfs_set_verifier_delegated(unsigned long *verf)
+{
+ *verf |= 1UL;
+}
+
+#if IS_ENABLED(CONFIG_NFS_V4)
+static void nfs_unset_verifier_delegated(unsigned long *verf)
+{
+ *verf &= ~1UL;
+}
+#endif /* IS_ENABLED(CONFIG_NFS_V4) */
+
+static bool nfs_test_verifier_delegated(unsigned long verf)
+{
+ return verf & 1;
+}
+
+static bool nfs_verifier_is_delegated(struct dentry *dentry)
+{
+ return nfs_test_verifier_delegated(dentry->d_time);
+}
+
+static void nfs_set_verifier_locked(struct dentry *dentry, unsigned long verf)
+{
+ struct inode *inode = d_inode(dentry);
+
+ if (!nfs_verifier_is_delegated(dentry) &&
+ !nfs_verify_change_attribute(d_inode(dentry->d_parent), verf))
+ goto out;
+ if (inode && NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
+ nfs_set_verifier_delegated(&verf);
+out:
+ dentry->d_time = verf;
+}
+
+/**
+ * nfs_set_verifier - save a parent directory verifier in the dentry
+ * @dentry: pointer to dentry
+ * @verf: verifier to save
+ *
+ * Saves the parent directory verifier in @dentry. If the inode has
+ * a delegation, we also tag the dentry as having been revalidated
+ * while holding a delegation so that we know we don't have to
+ * look it up again after a directory change.
+ */
+void nfs_set_verifier(struct dentry *dentry, unsigned long verf)
+{
+
+ spin_lock(&dentry->d_lock);
+ nfs_set_verifier_locked(dentry, verf);
+ spin_unlock(&dentry->d_lock);
+}
+EXPORT_SYMBOL_GPL(nfs_set_verifier);
+
+#if IS_ENABLED(CONFIG_NFS_V4)
+/**
+ * nfs_clear_verifier_delegated - clear the dir verifier delegation tag
+ * @inode: pointer to inode
+ *
+ * Iterates through the dentries in the inode alias list and clears
+ * the tag used to indicate that the dentry has been revalidated
+ * while holding a delegation.
+ * This function is intended for use when the delegation is being
+ * returned or revoked.
+ */
+void nfs_clear_verifier_delegated(struct inode *inode)
+{
+ struct dentry *alias;
+
+ if (!inode)
+ return;
+ spin_lock(&inode->i_lock);
+ hlist_for_each_entry(alias, &inode->i_dentry, d_u.d_alias) {
+ spin_lock(&alias->d_lock);
+ nfs_unset_verifier_delegated(&alias->d_time);
+ spin_unlock(&alias->d_lock);
+ }
+ spin_unlock(&inode->i_lock);
+}
+EXPORT_SYMBOL_GPL(nfs_clear_verifier_delegated);
+#endif /* IS_ENABLED(CONFIG_NFS_V4) */
+
/*
* A check for whether or not the parent directory has changed.
* In the case it has, we assume that the dentries are untrustworthy
struct nfs_fh *fhandle;
struct nfs_fattr *fattr;
struct nfs4_label *label;
+ unsigned long dir_verifier;
int ret;
ret = -ENOMEM;
if (fhandle == NULL || fattr == NULL || IS_ERR(label))
goto out;
- ret = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr, label);
+ dir_verifier = nfs_save_change_attribute(dir);
+ ret = NFS_PROTO(dir)->lookup(dir, dentry, fhandle, fattr, label);
if (ret < 0) {
- if (ret == -ESTALE || ret == -ENOENT)
+ switch (ret) {
+ case -ESTALE:
+ case -ENOENT:
ret = 0;
+ break;
+ case -ETIMEDOUT:
+ if (NFS_SERVER(inode)->flags & NFS_MOUNT_SOFTREVAL)
+ ret = 1;
+ }
goto out;
}
ret = 0;
goto out;
nfs_setsecurity(inode, fattr, label);
- nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
+ nfs_set_verifier(dentry, dir_verifier);
/* set a readdirplus hint that we had a cache miss */
nfs_force_use_readdirplus(dir);
goto out_bad;
}
- if (NFS_PROTO(dir)->have_delegation(inode, FMODE_READ))
+ if (nfs_verifier_is_delegated(dentry))
return nfs_lookup_revalidate_delegated(dir, dentry, inode);
/* Force a full look up iff the parent directory has changed */
struct nfs_fh *fhandle = NULL;
struct nfs_fattr *fattr = NULL;
struct nfs4_label *label = NULL;
+ unsigned long dir_verifier;
int error;
dfprintk(VFS, "NFS: lookup(%pd2)\n", dentry);
if (IS_ERR(label))
goto out;
+ dir_verifier = nfs_save_change_attribute(dir);
trace_nfs_lookup_enter(dir, dentry, flags);
- error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr, label);
+ error = NFS_PROTO(dir)->lookup(dir, dentry, fhandle, fattr, label);
if (error == -ENOENT)
goto no_entry;
if (error < 0) {
goto out_label;
dentry = res;
}
- nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
+ nfs_set_verifier(dentry, dir_verifier);
out_label:
trace_nfs_lookup_exit(dir, dentry, flags, error);
nfs4_label_free(label);
if (inode == NULL)
goto full_reval;
- if (NFS_PROTO(dir)->have_delegation(inode, FMODE_READ))
+ if (nfs_verifier_is_delegated(dentry))
return nfs_lookup_revalidate_delegated(dir, dentry, inode);
/* NFS only supports OPEN on regular files */
d_drop(dentry);
if (fhandle->size == 0) {
- error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr, NULL);
+ error = NFS_PROTO(dir)->lookup(dir, dentry, fhandle, fattr, NULL);
if (error)
goto out_error;
}
/* Found an entry, is our attribute cache valid? */
if (!nfs_check_cache_invalid(inode, NFS_INO_INVALID_ACCESS))
break;
+ if (!retry)
+ break;
err = -ECHILD;
if (!may_block)
goto out;
- if (!retry)
- goto out_zap;
spin_unlock(&inode->i_lock);
err = __nfs_revalidate_inode(NFS_SERVER(inode), inode);
if (err)
lh = rcu_dereference(nfsi->access_cache_entry_lru.prev);
cache = list_entry(lh, struct nfs_access_entry, lru);
if (lh == &nfsi->access_cache_entry_lru ||
- cred != cache->cred)
+ cred_fscmp(cred, cache->cred) != 0)
cache = NULL;
if (cache == NULL)
goto out;
{
struct nfs_access_entry cache;
bool may_block = (mask & MAY_NOT_BLOCK) == 0;
- int cache_mask;
+ int cache_mask = -1;
int status;
trace_nfs_access_enter(inode);
if ((mask & ~cache_mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) != 0)
status = -EACCES;
out:
- trace_nfs_access_exit(inode, status);
+ trace_nfs_access_exit(inode, mask, cache_mask, status);
return status;
}
projects / linux.git / blobdiff