Viewing: llite_nfs.c
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
* Use is subject to license terms.
*
* Copyright (c) 2011, 2017, Intel Corporation.
*/
/*
* This file is part of Lustre, http://www.lustre.org/
*
* NFS export of Lustre Light File System
*
* Author: Yury Umanets <umka@clusterfs.com>
* Author: Huang Hua <huanghua@clusterfs.com>
*/
#define DEBUG_SUBSYSTEM S_LLITE
#include <linux/exportfs.h>
#include <lustre_fid.h>
#include "llite_internal.h"
u32 get_uuid2int(const char *name, int len)
{
u32 key0 = 0x12a3fe2d, key1 = 0x37abe8f9;
while (len--) {
u32 key = key1 + (key0 ^ (*name++ * 7152373));
if (key & 0x80000000)
key -= 0x7fffffff;
key1 = key0;
key0 = key;
}
return (key0 << 1);
}
struct inode *search_inode_for_lustre(struct super_block *sb,
const struct lu_fid *fid)
{
struct ll_sb_info *sbi = ll_s2sbi(sb);
struct ptlrpc_request *req = NULL;
struct inode *inode = NULL;
int eadatalen = 0;
unsigned long hash = cl_fid_build_ino(fid, ll_need_32bit_api(sbi));
struct md_op_data *op_data;
int rc;
ENTRY;
CDEBUG(D_INFO, "searching inode for:(%lu,"DFID")\n", hash, PFID(fid));
inode = ilookup5(sb, hash, ll_test_inode_by_fid, (void *)fid);
if (inode)
RETURN(inode);
rc = ll_get_default_mdsize(sbi, &eadatalen);
if (rc)
RETURN(ERR_PTR(rc));
/*
* Because inode is NULL, ll_prep_md_op_data can not
* be used here. So we allocate op_data ourselves
*/
OBD_ALLOC_PTR(op_data);
if (!op_data)
return ERR_PTR(-ENOMEM);
op_data->op_fid1 = *fid;
op_data->op_mode = eadatalen;
op_data->op_valid = OBD_MD_FLEASIZE;
/* mds_fid2dentry ignores f_type */
rc = md_getattr(sbi->ll_md_exp, op_data, &req);
OBD_FREE_PTR(op_data);
if (rc) {
/*
* Suppress erroneous/confusing messages when NFS
* is out of sync and requests old data.
*/
CDEBUG(D_INFO, "can't get object attrs, fid "DFID", rc %d\n",
PFID(fid), rc);
RETURN(ERR_PTR(rc));
}
rc = ll_prep_inode(&inode, &req->rq_pill, sb, NULL);
ptlrpc_req_put(req);
if (rc)
RETURN(ERR_PTR(rc));
RETURN(inode);
}
static struct dentry *
ll_iget_for_nfs(struct super_block *sb, struct lu_fid *fid, struct lu_fid *parent)
{
bool is_dot_lustre = fid_is_dot_lustre(fid);
struct dentry *result;
struct inode *inode;
ENTRY;
if (!fid_is_sane(fid))
RETURN(ERR_PTR(-ESTALE));
CDEBUG(D_INFO, "Get dentry for fid: "DFID"\n", PFID(fid));
if (fid_is_root(fid))
RETURN(dget(sb->s_root));
inode = search_inode_for_lustre(sb, fid);
if (IS_ERR(inode))
RETURN(ERR_CAST(inode));
if (is_bad_inode(inode)) {
/* we didn't find the right inode.. */
iput(inode);
RETURN(ERR_PTR(-ESTALE));
}
/* Both LU_DOT_LUSTRE_FID and LU_OBF_FID are special fids that
* don't match to a real searchable file, so they need special
* handling.
*/
if (is_dot_lustre || fid_is_obf(fid)) {
struct qstr dot_name = QSTR_INIT(".lustre",
strlen(".lustre"));
struct dentry *dot, *obf;
inode_lock(d_inode(sb->s_root));
dot = d_lookup(sb->s_root, &dot_name);
if (!dot) {
struct inode *tmp = inode;
dot = d_alloc(sb->s_root, &dot_name);
if (!dot) {
inode_unlock(d_inode(sb->s_root));
iput(inode);
RETURN(ERR_PTR(-ENOMEM));
}
/* We are requesting OBF fid then locate inode of
* .lustre FID
*/
if (!is_dot_lustre) {
tmp = search_inode_for_lustre(sb,
&LU_DOT_LUSTRE_FID);
if (IS_ERR(tmp)) {
inode_unlock(d_inode(sb->s_root));
obf = ERR_CAST(tmp);
goto free_dot;
}
}
/* Successfully add .lustre dentry to dcache. For future
* failures for the obf case we don't need to iput the
* .lustre inode.
*/
d_add(dot, tmp);
}
inode_unlock(d_inode(sb->s_root));
if (!is_dot_lustre) {
struct qstr obf_name = QSTR_INIT("fid", strlen("fid"));
inode_lock(d_inode(dot));
obf = d_lookup(dot, &obf_name);
if (!obf) {
obf = d_alloc(dot, &obf_name);
if (!obf) {
inode_unlock(d_inode(dot));
obf = ERR_PTR(-ENOMEM);
goto free_dot;
}
d_add(obf, inode);
}
inode_unlock(d_inode(dot));
free_dot:
if (IS_ERR(obf))
iput(inode);
dput(dot);
result = obf;
} else {
result = dot;
}
RETURN(result);
}
/* N.B. d_obtain_alias() drops inode ref on error */
result = d_obtain_alias(inode);
if (IS_ERR(result))
RETURN(result);
if ((current->flags & PF_KTHREAD) && !strcmp(current->comm, "nfsd")) {
struct ll_sb_info *sbi = ll_i2sbi(inode);
/* knfsd uses this from kernel, disable splice(). LU-19255 */
if (S_ISREG(inode->i_mode)) {
inode->i_fop = ll_select_file_operations(sbi, false);
LASSERT(inode->i_fop->splice_read == NULL);
}
#if LINUX_VERSION_CODE < KERNEL_VERSION(5, 5, 0)
/* If we are called by nfsd kthread set lli_open_thrsh_count
* to one. This will force caching the open lock. To be
* removed once oldest supported Linux kernel is 5.5
*/
{
struct ll_inode_info *lli = ll_i2info(inode);
lli->lli_open_thrsh_count = 1;
}
#endif
}
RETURN(result);
}
#ifndef FILEID_INVALID
#define FILEID_INVALID 0xff
#endif
#ifndef FILEID_LUSTRE
#define FILEID_LUSTRE 0x97
#endif
/**
* ll_encode_fh() - Encode file handle (NFS)
* @inode: inode of file which is being encoded
* @fh: file handle buffer
* @plen: length of file handle (fh) buffer
* @parent: inode of parent directory
*
* Return:
* The return value is file handle type:
* * %1 -- contains child file handle;
* * %2 -- contains child file handle and parent file handle;
* * %255 -- error.
*/
static int ll_encode_fh(struct inode *inode, u32 *fh, int *plen,
struct inode *parent)
{
int fileid_len = sizeof(struct lustre_file_handle) / 4;
struct lustre_file_handle *lfh = (void *)fh;
ENTRY;
CDEBUG(D_INFO, "%s: encoding for ("DFID") maxlen=%d minlen=%d\n",
ll_i2sbi(inode)->ll_fsname,
PFID(ll_inode2fid(inode)), *plen, fileid_len);
if (*plen < fileid_len) {
*plen = fileid_len;
RETURN(FILEID_INVALID);
}
lfh->lfh_child = *ll_inode2fid(inode);
if (parent)
lfh->lfh_parent = *ll_inode2fid(parent);
else
fid_zero(&lfh->lfh_parent);
*plen = fileid_len;
RETURN(FILEID_LUSTRE);
}
static inline int
do_nfs_get_name_filldir(struct ll_getname_data *lgd, const char *name,
int namelen, loff_t hash, u64 ino, unsigned int type)
{
/*
* It is hack to access lde_fid for comparison with lgd_fid.
* So the input 'name' must be part of the 'lu_dirent', and
* so must appear to be a non-const pointer to an empty array.
*/
char (*n)[0] = (void *)name;
/* NOTE: This should be container_of(). However container_of() in
* kernels earlier than v4.13-rc1~37^2~94 cause this to generate a
* warning, which fails when we compile with -Werror. Those earlier
* kernels don't have container_of_safe, calling that instead will use
* the lustre-local version which doesn't generate the warning.
*/
struct lu_dirent *lde = container_of_safe(n, struct lu_dirent, lde_name);
struct lu_fid fid;
fid_le_to_cpu(&fid, &lde->lde_fid);
if (lu_fid_eq(&fid, &lgd->lgd_fid)) {
memcpy(lgd->lgd_name, name, namelen);
lgd->lgd_name[namelen] = 0;
lgd->lgd_found = 1;
}
return lgd->lgd_found;
}
static FILLDIR_TYPE
ll_nfs_get_name_filldir(struct dir_context *ctx, const char *name, int namelen,
loff_t hash, u64 ino, unsigned int type)
{
struct ll_getname_data *lgd =
container_of(ctx, struct ll_getname_data, ctx);
int err;
err = do_nfs_get_name_filldir(lgd, name, namelen, hash, ino, type);
#ifdef HAVE_FILLDIR_USE_CTX_RETURN_BOOL
return err == 0;
#else
return err;
#endif
}
static int ll_get_name(struct dentry *dentry, char *name, struct dentry *child)
{
struct inode *dir = dentry->d_inode;
struct ll_getname_data lgd = {
.lgd_name = name,
.lgd_fid = ll_i2info(child->d_inode)->lli_fid,
.ctx.actor = (filldir_t)ll_nfs_get_name_filldir,
.lgd_found = 0,
};
struct md_op_data *op_data;
u64 pos = 0;
int rc;
ENTRY;
if (!dir || !S_ISDIR(dir->i_mode))
GOTO(out, rc = -ENOTDIR);
if (!dir->i_fop)
GOTO(out, rc = -EINVAL);
op_data = ll_prep_md_op_data(NULL, dir, dir, NULL, 0, 0,
LUSTRE_OPC_ANY, dir);
if (IS_ERR(op_data))
GOTO(out, rc = PTR_ERR(op_data));
inode_lock(dir);
rc = ll_dir_read(dir, &pos, op_data, &lgd.ctx, NULL);
inode_unlock(dir);
ll_finish_md_op_data(op_data);
if (!rc && !lgd.lgd_found)
rc = -ENOENT;
EXIT;
out:
return rc;
}
static struct dentry *ll_fh_to_dentry(struct super_block *sb, struct fid *fid,
int fh_len, int fh_type)
{
struct lustre_file_handle *lfh = (struct lustre_file_handle *)fid;
if (fh_type != FILEID_LUSTRE)
RETURN(ERR_PTR(-EPROTO));
RETURN(ll_iget_for_nfs(sb, &lfh->lfh_child, &lfh->lfh_parent));
}
static struct dentry *ll_fh_to_parent(struct super_block *sb, struct fid *fid,
int fh_len, int fh_type)
{
struct lustre_file_handle *lfh = (struct lustre_file_handle *)fid;
if (fh_type != FILEID_LUSTRE)
RETURN(ERR_PTR(-EPROTO));
RETURN(ll_iget_for_nfs(sb, &lfh->lfh_parent, NULL));
}
int ll_dir_get_parent_fid(struct inode *dir, struct lu_fid *parent_fid)
{
struct ptlrpc_request *req = NULL;
struct ll_sb_info *sbi;
struct mdt_body *body;
static const char dotdot[] = "..";
struct md_op_data *op_data;
int rc;
int lmmsize;
ENTRY;
LASSERT(dir && S_ISDIR(dir->i_mode));
sbi = ll_s2sbi(dir->i_sb);
CDEBUG(D_INFO, "%s: getting parent for ("DFID")\n",
sbi->ll_fsname, PFID(ll_inode2fid(dir)));
rc = ll_get_default_mdsize(sbi, &lmmsize);
if (rc != 0)
RETURN(rc);
op_data = ll_prep_md_op_data(NULL, dir, NULL, dotdot,
strlen(dotdot), lmmsize,
LUSTRE_OPC_ANY, NULL);
if (IS_ERR(op_data))
RETURN(PTR_ERR(op_data));
rc = md_getattr_name(sbi->ll_md_exp, op_data, &req);
ll_finish_md_op_data(op_data);
if (rc != 0) {
CERROR("%s: failure inode "DFID" get parent: rc = %d\n",
sbi->ll_fsname, PFID(ll_inode2fid(dir)), rc);
RETURN(rc);
}
body = req_capsule_server_get(&req->rq_pill, &RMF_MDT_BODY);
/*
* LU-3952: MDT may lost the FID of its parent, we should not crash
* the NFS server, ll_iget_for_nfs() will handle the error.
*/
if (body->mbo_valid & OBD_MD_FLID) {
CDEBUG(D_INFO, "parent for "DFID" is "DFID"\n",
PFID(ll_inode2fid(dir)), PFID(&body->mbo_fid1));
*parent_fid = body->mbo_fid1;
}
ptlrpc_req_put(req);
RETURN(0);
}
static struct dentry *ll_get_parent(struct dentry *dchild)
{
struct lu_fid parent_fid = { 0 };
int rc;
struct dentry *dentry;
ENTRY;
rc = ll_dir_get_parent_fid(dchild->d_inode, &parent_fid);
if (rc != 0)
RETURN(ERR_PTR(rc));
dentry = ll_iget_for_nfs(dchild->d_inode->i_sb, &parent_fid, NULL);
RETURN(dentry);
}
const struct export_operations lustre_export_operations = {
.get_parent = ll_get_parent,
.encode_fh = ll_encode_fh,
.get_name = ll_get_name,
.fh_to_dentry = ll_fh_to_dentry,
.fh_to_parent = ll_fh_to_parent,
};
