vfs_inode_dotl.c

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/*
 *  linux/fs/9p/vfs_inode_dotl.c
 *
 * This file contains vfs inode ops for the 9P2000.L protocol.
 *
 *  Copyright (C) 2004 by Eric Van Hensbergen <[email protected]>
 *  Copyright (C) 2002 by Ron Minnich <[email protected]>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  as published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to:
 *  Free Software Foundation
 *  51 Franklin Street, Fifth Floor
 *  Boston, MA  02111-1301  USA
 *
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/pagemap.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/inet.h>
#include <linux/namei.h>
#include <linux/idr.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/xattr.h>
#include <linux/posix_acl.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>

#include "v9fs.h"
#include "v9fs_vfs.h"
#include "fid.h"
#include "cache.h"
#include "xattr.h"
#include "acl.h"

static int
v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
            dev_t rdev);

static gid_t v9fs_get_fsgid_for_create(struct inode *dir_inode)
{
    BUG_ON(dir_inode == NULL);

    if (dir_inode->i_mode & S_ISGID) {
        /* set_gid bit is set.*/
        return dir_inode->i_gid;
    }
    return current_fsgid();
}

static int v9fs_test_inode_dotl(struct inode *inode, void *data)
{
    struct v9fs_inode *v9inode = V9FS_I(inode);
    struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;

    /* don't match inode of different type */
    if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
        return 0;

    if (inode->i_generation != st->st_gen)
        return 0;

    /* compare qid details */
    if (memcmp(&v9inode->qid.version,
           &st->qid.version, sizeof(v9inode->qid.version)))
        return 0;

    if (v9inode->qid.type != st->qid.type)
        return 0;
    return 1;
}

/* Always get a new inode */
static int v9fs_test_new_inode_dotl(struct inode *inode, void *data)
{
    return 0;
}

static int v9fs_set_inode_dotl(struct inode *inode,  void *data)
{
    struct v9fs_inode *v9inode = V9FS_I(inode);
    struct p9_stat_dotl *st = (struct p9_stat_dotl *)data;

    memcpy(&v9inode->qid, &st->qid, sizeof(st->qid));
    inode->i_generation = st->st_gen;
    return 0;
}

static struct inode *v9fs_qid_iget_dotl(struct super_block *sb,
                    struct p9_qid *qid,
                    struct p9_fid *fid,
                    struct p9_stat_dotl *st,
                    int new)
{
    int retval;
    unsigned long i_ino;
    struct inode *inode;
    struct v9fs_session_info *v9ses = sb->s_fs_info;
    int (*test)(struct inode *, void *);

    if (new)
        test = v9fs_test_new_inode_dotl;
    else
        test = v9fs_test_inode_dotl;

    i_ino = v9fs_qid2ino(qid);
    inode = iget5_locked(sb, i_ino, test, v9fs_set_inode_dotl, st);
    if (!inode)
        return ERR_PTR(-ENOMEM);
    if (!(inode->i_state & I_NEW))
        return inode;
    /*
     * initialize the inode with the stat info
     * FIXME!! we may need support for stale inodes
     * later.
     */
    inode->i_ino = i_ino;
    retval = v9fs_init_inode(v9ses, inode,
                 st->st_mode, new_decode_dev(st->st_rdev));
    if (retval)
        goto error;

    v9fs_stat2inode_dotl(st, inode);
#ifdef CONFIG_9P_FSCACHE
    v9fs_cache_inode_get_cookie(inode);
#endif
    retval = v9fs_get_acl(inode, fid);
    if (retval)
        goto error;

    unlock_new_inode(inode);
    return inode;
error:
    unlock_new_inode(inode);
    iput(inode);
    return ERR_PTR(retval);

}

struct inode *
v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses, struct p9_fid *fid,
             struct super_block *sb, int new)
{
    struct p9_stat_dotl *st;
    struct inode *inode = NULL;

    st = p9_client_getattr_dotl(fid, P9_STATS_BASIC | P9_STATS_GEN);
    if (IS_ERR(st))
        return ERR_CAST(st);

    inode = v9fs_qid_iget_dotl(sb, &st->qid, fid, st, new);
    kfree(st);
    return inode;
}

struct dotl_openflag_map {
    int open_flag;
    int dotl_flag;
};

static int v9fs_mapped_dotl_flags(int flags)
{
    int i;
    int rflags = 0;
    struct dotl_openflag_map dotl_oflag_map[] = {
        { O_CREAT,  P9_DOTL_CREATE },
        { O_EXCL,   P9_DOTL_EXCL },
        { O_NOCTTY, P9_DOTL_NOCTTY },
        { O_TRUNC,  P9_DOTL_TRUNC },
        { O_APPEND, P9_DOTL_APPEND },
        { O_NONBLOCK,   P9_DOTL_NONBLOCK },
        { O_DSYNC,  P9_DOTL_DSYNC },
        { FASYNC,   P9_DOTL_FASYNC },
        { O_DIRECT, P9_DOTL_DIRECT },
        { O_LARGEFILE,  P9_DOTL_LARGEFILE },
        { O_DIRECTORY,  P9_DOTL_DIRECTORY },
        { O_NOFOLLOW,   P9_DOTL_NOFOLLOW },
        { O_NOATIME,    P9_DOTL_NOATIME },
        { O_CLOEXEC,    P9_DOTL_CLOEXEC },
        { O_SYNC,   P9_DOTL_SYNC},
    };
    for (i = 0; i < ARRAY_SIZE(dotl_oflag_map); i++) {
        if (flags & dotl_oflag_map[i].open_flag)
            rflags |= dotl_oflag_map[i].dotl_flag;
    }
    return rflags;
}

int v9fs_open_to_dotl_flags(int flags)
{
    int rflags = 0;

    /*
     * We have same bits for P9_DOTL_READONLY, P9_DOTL_WRONLY
     * and P9_DOTL_NOACCESS
     */
    rflags |= flags & O_ACCMODE;
    rflags |= v9fs_mapped_dotl_flags(flags);

    return rflags;
}

static int
v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
        bool excl)
{
    return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
}

static int
v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
              struct file *file, unsigned flags, umode_t omode,
              int *opened)
{
    int err = 0;
    gid_t gid;
    umode_t mode;
    char *name = NULL;
    struct p9_qid qid;
    struct inode *inode;
    struct p9_fid *fid = NULL;
    struct v9fs_inode *v9inode;
    struct p9_fid *dfid, *ofid, *inode_fid;
    struct v9fs_session_info *v9ses;
    struct posix_acl *pacl = NULL, *dacl = NULL;
    struct dentry *res = NULL;

    if (d_unhashed(dentry)) {
        res = v9fs_vfs_lookup(dir, dentry, 0);
        if (IS_ERR(res))
            return PTR_ERR(res);

        if (res)
            dentry = res;
    }

    /* Only creates */
    if (!(flags & O_CREAT) || dentry->d_inode)
        return finish_no_open(file, res);

    v9ses = v9fs_inode2v9ses(dir);

    name = (char *) dentry->d_name.name;
    p9_debug(P9_DEBUG_VFS, "name:%s flags:0x%x mode:0x%hx\n",
         name, flags, omode);

    dfid = v9fs_fid_lookup(dentry->d_parent);
    if (IS_ERR(dfid)) {
        err = PTR_ERR(dfid);
        p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
        goto out;
    }

    /* clone a fid to use for creation */
    ofid = p9_client_walk(dfid, 0, NULL, 1);
    if (IS_ERR(ofid)) {
        err = PTR_ERR(ofid);
        p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
        goto out;
    }

    gid = v9fs_get_fsgid_for_create(dir);

    mode = omode;
    /* Update mode based on ACL value */
    err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
    if (err) {
        p9_debug(P9_DEBUG_VFS, "Failed to get acl values in creat %d\n",
             err);
        goto error;
    }
    err = p9_client_create_dotl(ofid, name, v9fs_open_to_dotl_flags(flags),
                    mode, gid, &qid);
    if (err < 0) {
        p9_debug(P9_DEBUG_VFS, "p9_client_open_dotl failed in creat %d\n",
             err);
        goto error;
    }
    v9fs_invalidate_inode_attr(dir);

    /* instantiate inode and assign the unopened fid to the dentry */
    fid = p9_client_walk(dfid, 1, &name, 1);
    if (IS_ERR(fid)) {
        err = PTR_ERR(fid);
        p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
        fid = NULL;
        goto error;
    }
    inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
    if (IS_ERR(inode)) {
        err = PTR_ERR(inode);
        p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n", err);
        goto error;
    }
    err = v9fs_fid_add(dentry, fid);
    if (err < 0)
        goto error;
    d_instantiate(dentry, inode);

    /* Now set the ACL based on the default value */
    v9fs_set_create_acl(dentry, &dacl, &pacl);

    v9inode = V9FS_I(inode);
    mutex_lock(&v9inode->v_mutex);
    if (v9ses->cache && !v9inode->writeback_fid &&
        ((flags & O_ACCMODE) != O_RDONLY)) {
        /*
         * clone a fid and add it to writeback_fid
         * we do it during open time instead of
         * page dirty time via write_begin/page_mkwrite
         * because we want write after unlink usecase
         * to work.
         */
        inode_fid = v9fs_writeback_fid(dentry);
        if (IS_ERR(inode_fid)) {
            err = PTR_ERR(inode_fid);
            mutex_unlock(&v9inode->v_mutex);
            goto err_clunk_old_fid;
        }
        v9inode->writeback_fid = (void *) inode_fid;
    }
    mutex_unlock(&v9inode->v_mutex);
    /* Since we are opening a file, assign the open fid to the file */
    err = finish_open(file, dentry, generic_file_open, opened);
    if (err)
        goto err_clunk_old_fid;
    file->private_data = ofid;
#ifdef CONFIG_9P_FSCACHE
    if (v9ses->cache)
        v9fs_cache_inode_set_cookie(inode, file);
#endif
    *opened |= FILE_CREATED;
out:
    dput(res);
    return err;

error:
    if (fid)
        p9_client_clunk(fid);
err_clunk_old_fid:
    if (ofid)
        p9_client_clunk(ofid);
    v9fs_set_create_acl(NULL, &dacl, &pacl);
    goto out;
}

static int v9fs_vfs_mkdir_dotl(struct inode *dir,
                   struct dentry *dentry, umode_t omode)
{
    int err;
    struct v9fs_session_info *v9ses;
    struct p9_fid *fid = NULL, *dfid = NULL;
    gid_t gid;
    char *name;
    umode_t mode;
    struct inode *inode;
    struct p9_qid qid;
    struct dentry *dir_dentry;
    struct posix_acl *dacl = NULL, *pacl = NULL;

    p9_debug(P9_DEBUG_VFS, "name %s\n", dentry->d_name.name);
    err = 0;
    v9ses = v9fs_inode2v9ses(dir);

    omode |= S_IFDIR;
    if (dir->i_mode & S_ISGID)
        omode |= S_ISGID;

    dir_dentry = dentry->d_parent;
    dfid = v9fs_fid_lookup(dir_dentry);
    if (IS_ERR(dfid)) {
        err = PTR_ERR(dfid);
        p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
        dfid = NULL;
        goto error;
    }

    gid = v9fs_get_fsgid_for_create(dir);
    mode = omode;
    /* Update mode based on ACL value */
    err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
    if (err) {
        p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mkdir %d\n",
             err);
        goto error;
    }
    name = (char *) dentry->d_name.name;
    err = p9_client_mkdir_dotl(dfid, name, mode, gid, &qid);
    if (err < 0)
        goto error;

    /* instantiate inode and assign the unopened fid to the dentry */
    if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
        fid = p9_client_walk(dfid, 1, &name, 1);
        if (IS_ERR(fid)) {
            err = PTR_ERR(fid);
            p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
                 err);
            fid = NULL;
            goto error;
        }

        inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
        if (IS_ERR(inode)) {
            err = PTR_ERR(inode);
            p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
                 err);
            goto error;
        }
        err = v9fs_fid_add(dentry, fid);
        if (err < 0)
            goto error;
        d_instantiate(dentry, inode);
        fid = NULL;
    } else {
        /*
         * Not in cached mode. No need to populate
         * inode with stat. We need to get an inode
         * so that we can set the acl with dentry
         */
        inode = v9fs_get_inode(dir->i_sb, mode, 0);
        if (IS_ERR(inode)) {
            err = PTR_ERR(inode);
            goto error;
        }
        d_instantiate(dentry, inode);
    }
    /* Now set the ACL based on the default value */
    v9fs_set_create_acl(dentry, &dacl, &pacl);
    inc_nlink(dir);
    v9fs_invalidate_inode_attr(dir);
error:
    if (fid)
        p9_client_clunk(fid);
    v9fs_set_create_acl(NULL, &dacl, &pacl);
    return err;
}

static int
v9fs_vfs_getattr_dotl(struct vfsmount *mnt, struct dentry *dentry,
         struct kstat *stat)
{
    int err;
    struct v9fs_session_info *v9ses;
    struct p9_fid *fid;
    struct p9_stat_dotl *st;

    p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);
    err = -EPERM;
    v9ses = v9fs_dentry2v9ses(dentry);
    if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
        generic_fillattr(dentry->d_inode, stat);
        return 0;
    }
    fid = v9fs_fid_lookup(dentry);
    if (IS_ERR(fid))
        return PTR_ERR(fid);

    /* Ask for all the fields in stat structure. Server will return
     * whatever it supports
     */

    st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
    if (IS_ERR(st))
        return PTR_ERR(st);

    v9fs_stat2inode_dotl(st, dentry->d_inode);
    generic_fillattr(dentry->d_inode, stat);
    /* Change block size to what the server returned */
    stat->blksize = st->st_blksize;

    kfree(st);
    return 0;
}

/*
 * Attribute flags.
 */
#define P9_ATTR_MODE        (1 << 0)
#define P9_ATTR_UID     (1 << 1)
#define P9_ATTR_GID     (1 << 2)
#define P9_ATTR_SIZE        (1 << 3)
#define P9_ATTR_ATIME       (1 << 4)
#define P9_ATTR_MTIME       (1 << 5)
#define P9_ATTR_CTIME       (1 << 6)
#define P9_ATTR_ATIME_SET   (1 << 7)
#define P9_ATTR_MTIME_SET   (1 << 8)

struct dotl_iattr_map {
    int iattr_valid;
    int p9_iattr_valid;
};

static int v9fs_mapped_iattr_valid(int iattr_valid)
{
    int i;
    int p9_iattr_valid = 0;
    struct dotl_iattr_map dotl_iattr_map[] = {
        { ATTR_MODE,        P9_ATTR_MODE },
        { ATTR_UID,     P9_ATTR_UID },
        { ATTR_GID,     P9_ATTR_GID },
        { ATTR_SIZE,        P9_ATTR_SIZE },
        { ATTR_ATIME,       P9_ATTR_ATIME },
        { ATTR_MTIME,       P9_ATTR_MTIME },
        { ATTR_CTIME,       P9_ATTR_CTIME },
        { ATTR_ATIME_SET,   P9_ATTR_ATIME_SET },
        { ATTR_MTIME_SET,   P9_ATTR_MTIME_SET },
    };
    for (i = 0; i < ARRAY_SIZE(dotl_iattr_map); i++) {
        if (iattr_valid & dotl_iattr_map[i].iattr_valid)
            p9_iattr_valid |= dotl_iattr_map[i].p9_iattr_valid;
    }
    return p9_iattr_valid;
}

int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
{
    int retval;
    struct v9fs_session_info *v9ses;
    struct p9_fid *fid;
    struct p9_iattr_dotl p9attr;

    p9_debug(P9_DEBUG_VFS, "\n");

    retval = inode_change_ok(dentry->d_inode, iattr);
    if (retval)
        return retval;

    p9attr.valid = v9fs_mapped_iattr_valid(iattr->ia_valid);
    p9attr.mode = iattr->ia_mode;
    p9attr.uid = iattr->ia_uid;
    p9attr.gid = iattr->ia_gid;
    p9attr.size = iattr->ia_size;
    p9attr.atime_sec = iattr->ia_atime.tv_sec;
    p9attr.atime_nsec = iattr->ia_atime.tv_nsec;
    p9attr.mtime_sec = iattr->ia_mtime.tv_sec;
    p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;

    retval = -EPERM;
    v9ses = v9fs_dentry2v9ses(dentry);
    fid = v9fs_fid_lookup(dentry);
    if (IS_ERR(fid))
        return PTR_ERR(fid);

    /* Write all dirty data */
    if (S_ISREG(dentry->d_inode->i_mode))
        filemap_write_and_wait(dentry->d_inode->i_mapping);

    retval = p9_client_setattr(fid, &p9attr);
    if (retval < 0)
        return retval;

    if ((iattr->ia_valid & ATTR_SIZE) &&
        iattr->ia_size != i_size_read(dentry->d_inode))
        truncate_setsize(dentry->d_inode, iattr->ia_size);

    v9fs_invalidate_inode_attr(dentry->d_inode);
    setattr_copy(dentry->d_inode, iattr);
    mark_inode_dirty(dentry->d_inode);
    if (iattr->ia_valid & ATTR_MODE) {
        /* We also want to update ACL when we update mode bits */
        retval = v9fs_acl_chmod(dentry);
        if (retval < 0)
            return retval;
    }
    return 0;
}

void
v9fs_stat2inode_dotl(struct p9_stat_dotl *stat, struct inode *inode)
{
    umode_t mode;
    struct v9fs_inode *v9inode = V9FS_I(inode);

    if ((stat->st_result_mask & P9_STATS_BASIC) == P9_STATS_BASIC) {
        inode->i_atime.tv_sec = stat->st_atime_sec;
        inode->i_atime.tv_nsec = stat->st_atime_nsec;
        inode->i_mtime.tv_sec = stat->st_mtime_sec;
        inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
        inode->i_ctime.tv_sec = stat->st_ctime_sec;
        inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
        inode->i_uid = stat->st_uid;
        inode->i_gid = stat->st_gid;
        set_nlink(inode, stat->st_nlink);

        mode = stat->st_mode & S_IALLUGO;
        mode |= inode->i_mode & ~S_IALLUGO;
        inode->i_mode = mode;

        i_size_write(inode, stat->st_size);
        inode->i_blocks = stat->st_blocks;
    } else {
        if (stat->st_result_mask & P9_STATS_ATIME) {
            inode->i_atime.tv_sec = stat->st_atime_sec;
            inode->i_atime.tv_nsec = stat->st_atime_nsec;
        }
        if (stat->st_result_mask & P9_STATS_MTIME) {
            inode->i_mtime.tv_sec = stat->st_mtime_sec;
            inode->i_mtime.tv_nsec = stat->st_mtime_nsec;
        }
        if (stat->st_result_mask & P9_STATS_CTIME) {
            inode->i_ctime.tv_sec = stat->st_ctime_sec;
            inode->i_ctime.tv_nsec = stat->st_ctime_nsec;
        }
        if (stat->st_result_mask & P9_STATS_UID)
            inode->i_uid = stat->st_uid;
        if (stat->st_result_mask & P9_STATS_GID)
            inode->i_gid = stat->st_gid;
        if (stat->st_result_mask & P9_STATS_NLINK)
            set_nlink(inode, stat->st_nlink);
        if (stat->st_result_mask & P9_STATS_MODE) {
            inode->i_mode = stat->st_mode;
            if ((S_ISBLK(inode->i_mode)) ||
                        (S_ISCHR(inode->i_mode)))
                init_special_inode(inode, inode->i_mode,
                                inode->i_rdev);
        }
        if (stat->st_result_mask & P9_STATS_RDEV)
            inode->i_rdev = new_decode_dev(stat->st_rdev);
        if (stat->st_result_mask & P9_STATS_SIZE)
            i_size_write(inode, stat->st_size);
        if (stat->st_result_mask & P9_STATS_BLOCKS)
            inode->i_blocks = stat->st_blocks;
    }
    if (stat->st_result_mask & P9_STATS_GEN)
        inode->i_generation = stat->st_gen;

    /* Currently we don't support P9_STATS_BTIME and P9_STATS_DATA_VERSION
     * because the inode structure does not have fields for them.
     */
    v9inode->cache_validity &= ~V9FS_INO_INVALID_ATTR;
}

static int
v9fs_vfs_symlink_dotl(struct inode *dir, struct dentry *dentry,
        const char *symname)
{
    int err;
    gid_t gid;
    char *name;
    struct p9_qid qid;
    struct inode *inode;
    struct p9_fid *dfid;
    struct p9_fid *fid = NULL;
    struct v9fs_session_info *v9ses;

    name = (char *) dentry->d_name.name;
    p9_debug(P9_DEBUG_VFS, "%lu,%s,%s\n", dir->i_ino, name, symname);
    v9ses = v9fs_inode2v9ses(dir);

    dfid = v9fs_fid_lookup(dentry->d_parent);
    if (IS_ERR(dfid)) {
        err = PTR_ERR(dfid);
        p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
        return err;
    }

    gid = v9fs_get_fsgid_for_create(dir);

    /* Server doesn't alter fid on TSYMLINK. Hence no need to clone it. */
    err = p9_client_symlink(dfid, name, (char *)symname, gid, &qid);

    if (err < 0) {
        p9_debug(P9_DEBUG_VFS, "p9_client_symlink failed %d\n", err);
        goto error;
    }

    v9fs_invalidate_inode_attr(dir);
    if (v9ses->cache) {
        /* Now walk from the parent so we can get an unopened fid. */
        fid = p9_client_walk(dfid, 1, &name, 1);
        if (IS_ERR(fid)) {
            err = PTR_ERR(fid);
            p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
                 err);
            fid = NULL;
            goto error;
        }

        /* instantiate inode and assign the unopened fid to dentry */
        inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
        if (IS_ERR(inode)) {
            err = PTR_ERR(inode);
            p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
                 err);
            goto error;
        }
        err = v9fs_fid_add(dentry, fid);
        if (err < 0)
            goto error;
        d_instantiate(dentry, inode);
        fid = NULL;
    } else {
        /* Not in cached mode. No need to populate inode with stat */
        inode = v9fs_get_inode(dir->i_sb, S_IFLNK, 0);
        if (IS_ERR(inode)) {
            err = PTR_ERR(inode);
            goto error;
        }
        d_instantiate(dentry, inode);
    }

error:
    if (fid)
        p9_client_clunk(fid);

    return err;
}

static int
v9fs_vfs_link_dotl(struct dentry *old_dentry, struct inode *dir,
        struct dentry *dentry)
{
    int err;
    char *name;
    struct dentry *dir_dentry;
    struct p9_fid *dfid, *oldfid;
    struct v9fs_session_info *v9ses;

    p9_debug(P9_DEBUG_VFS, "dir ino: %lu, old_name: %s, new_name: %s\n",
         dir->i_ino, old_dentry->d_name.name, dentry->d_name.name);

    v9ses = v9fs_inode2v9ses(dir);
    dir_dentry = dentry->d_parent;
    dfid = v9fs_fid_lookup(dir_dentry);
    if (IS_ERR(dfid))
        return PTR_ERR(dfid);

    oldfid = v9fs_fid_lookup(old_dentry);
    if (IS_ERR(oldfid))
        return PTR_ERR(oldfid);

    name = (char *) dentry->d_name.name;

    err = p9_client_link(dfid, oldfid, (char *)dentry->d_name.name);

    if (err < 0) {
        p9_debug(P9_DEBUG_VFS, "p9_client_link failed %d\n", err);
        return err;
    }

    v9fs_invalidate_inode_attr(dir);
    if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
        /* Get the latest stat info from server. */
        struct p9_fid *fid;
        fid = v9fs_fid_lookup(old_dentry);
        if (IS_ERR(fid))
            return PTR_ERR(fid);

        v9fs_refresh_inode_dotl(fid, old_dentry->d_inode);
    }
    ihold(old_dentry->d_inode);
    d_instantiate(dentry, old_dentry->d_inode);

    return err;
}

static int
v9fs_vfs_mknod_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
        dev_t rdev)
{
    int err;
    gid_t gid;
    char *name;
    umode_t mode;
    struct v9fs_session_info *v9ses;
    struct p9_fid *fid = NULL, *dfid = NULL;
    struct inode *inode;
    struct p9_qid qid;
    struct dentry *dir_dentry;
    struct posix_acl *dacl = NULL, *pacl = NULL;

    p9_debug(P9_DEBUG_VFS, " %lu,%s mode: %hx MAJOR: %u MINOR: %u\n",
         dir->i_ino, dentry->d_name.name, omode,
         MAJOR(rdev), MINOR(rdev));

    if (!new_valid_dev(rdev))
        return -EINVAL;

    v9ses = v9fs_inode2v9ses(dir);
    dir_dentry = dentry->d_parent;
    dfid = v9fs_fid_lookup(dir_dentry);
    if (IS_ERR(dfid)) {
        err = PTR_ERR(dfid);
        p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
        dfid = NULL;
        goto error;
    }

    gid = v9fs_get_fsgid_for_create(dir);
    mode = omode;
    /* Update mode based on ACL value */
    err = v9fs_acl_mode(dir, &mode, &dacl, &pacl);
    if (err) {
        p9_debug(P9_DEBUG_VFS, "Failed to get acl values in mknod %d\n",
             err);
        goto error;
    }
    name = (char *) dentry->d_name.name;

    err = p9_client_mknod_dotl(dfid, name, mode, rdev, gid, &qid);
    if (err < 0)
        goto error;

    v9fs_invalidate_inode_attr(dir);
    /* instantiate inode and assign the unopened fid to the dentry */
    if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
        fid = p9_client_walk(dfid, 1, &name, 1);
        if (IS_ERR(fid)) {
            err = PTR_ERR(fid);
            p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n",
                 err);
            fid = NULL;
            goto error;
        }

        inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb);
        if (IS_ERR(inode)) {
            err = PTR_ERR(inode);
            p9_debug(P9_DEBUG_VFS, "inode creation failed %d\n",
                 err);
            goto error;
        }
        err = v9fs_fid_add(dentry, fid);
        if (err < 0)
            goto error;
        d_instantiate(dentry, inode);
        fid = NULL;
    } else {
        /*
         * Not in cached mode. No need to populate inode with stat.
         * socket syscall returns a fd, so we need instantiate
         */
        inode = v9fs_get_inode(dir->i_sb, mode, rdev);
        if (IS_ERR(inode)) {
            err = PTR_ERR(inode);
            goto error;
        }
        d_instantiate(dentry, inode);
    }
    /* Now set the ACL based on the default value */
    v9fs_set_create_acl(dentry, &dacl, &pacl);
error:
    if (fid)
        p9_client_clunk(fid);
    v9fs_set_create_acl(NULL, &dacl, &pacl);
    return err;
}

static void *
v9fs_vfs_follow_link_dotl(struct dentry *dentry, struct nameidata *nd)
{
    int retval;
    struct p9_fid *fid;
    char *link = __getname();
    char *target;

    p9_debug(P9_DEBUG_VFS, "%s\n", dentry->d_name.name);

    if (!link) {
        link = ERR_PTR(-ENOMEM);
        goto ndset;
    }
    fid = v9fs_fid_lookup(dentry);
    if (IS_ERR(fid)) {
        __putname(link);
        link = ERR_CAST(fid);
        goto ndset;
    }
    retval = p9_client_readlink(fid, &target);
    if (!retval) {
        strcpy(link, target);
        kfree(target);
        goto ndset;
    }
    __putname(link);
    link = ERR_PTR(retval);
ndset:
    nd_set_link(nd, link);
    return NULL;
}

int v9fs_refresh_inode_dotl(struct p9_fid *fid, struct inode *inode)
{
    loff_t i_size;
    struct p9_stat_dotl *st;
    struct v9fs_session_info *v9ses;

    v9ses = v9fs_inode2v9ses(inode);
    st = p9_client_getattr_dotl(fid, P9_STATS_ALL);
    if (IS_ERR(st))
        return PTR_ERR(st);
    /*
     * Don't update inode if the file type is different
     */
    if ((inode->i_mode & S_IFMT) != (st->st_mode & S_IFMT))
        goto out;

    spin_lock(&inode->i_lock);
    /*
     * We don't want to refresh inode->i_size,
     * because we may have cached data
     */
    i_size = inode->i_size;
    v9fs_stat2inode_dotl(st, inode);
    if (v9ses->cache)
        inode->i_size = i_size;
    spin_unlock(&inode->i_lock);
out:
    kfree(st);
    return 0;
}

const struct inode_operations v9fs_dir_inode_operations_dotl = {
    .create = v9fs_vfs_create_dotl,
    .atomic_open = v9fs_vfs_atomic_open_dotl,
    .lookup = v9fs_vfs_lookup,
    .link = v9fs_vfs_link_dotl,
    .symlink = v9fs_vfs_symlink_dotl,
    .unlink = v9fs_vfs_unlink,
    .mkdir = v9fs_vfs_mkdir_dotl,
    .rmdir = v9fs_vfs_rmdir,
    .mknod = v9fs_vfs_mknod_dotl,
    .rename = v9fs_vfs_rename,
    .getattr = v9fs_vfs_getattr_dotl,
    .setattr = v9fs_vfs_setattr_dotl,
    .setxattr = generic_setxattr,
    .getxattr = generic_getxattr,
    .removexattr = generic_removexattr,
    .listxattr = v9fs_listxattr,
    .get_acl = v9fs_iop_get_acl,
};

const struct inode_operations v9fs_file_inode_operations_dotl = {
    .getattr = v9fs_vfs_getattr_dotl,
    .setattr = v9fs_vfs_setattr_dotl,
    .setxattr = generic_setxattr,
    .getxattr = generic_getxattr,
    .removexattr = generic_removexattr,
    .listxattr = v9fs_listxattr,
    .get_acl = v9fs_iop_get_acl,
};

const struct inode_operations v9fs_symlink_inode_operations_dotl = {
    .readlink = generic_readlink,
    .follow_link = v9fs_vfs_follow_link_dotl,
    .put_link = v9fs_vfs_put_link,
    .getattr = v9fs_vfs_getattr_dotl,
    .setattr = v9fs_vfs_setattr_dotl,
    .setxattr = generic_setxattr,
    .getxattr = generic_getxattr,
    .removexattr = generic_removexattr,
    .listxattr = v9fs_listxattr,
};