android_kernel_xiaomi_sm8350/fs/gfs2/inode.c
Steven Whitehouse 1be3867955 [GFS2] Fix bz 229831, lookup returns wrong inode
The following patch fixes Red Hat bz 229831. Without this patch its
possible for the wrong inode to be returned in certain cases. It is a
pretty unusual event, so that its taken some time to track down. Thanks
and due to Josef Whiter who did a lot of the testing required to thrack
this down and fix it.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-03-07 14:01:53 -05:00

1255 lines
28 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/posix_acl.h>
#include <linux/sort.h>
#include <linux/gfs2_ondisk.h>
#include <linux/crc32.h>
#include <linux/lm_interface.h>
#include <linux/security.h>
#include "gfs2.h"
#include "incore.h"
#include "acl.h"
#include "bmap.h"
#include "dir.h"
#include "eattr.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "log.h"
#include "meta_io.h"
#include "ops_address.h"
#include "ops_file.h"
#include "ops_inode.h"
#include "quota.h"
#include "rgrp.h"
#include "trans.h"
#include "util.h"
static int iget_test(struct inode *inode, void *opaque)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_inum_host *inum = opaque;
if (ip->i_num.no_addr == inum->no_addr &&
inode->i_private != NULL)
return 1;
return 0;
}
static int iget_set(struct inode *inode, void *opaque)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_inum_host *inum = opaque;
ip->i_num = *inum;
inode->i_ino = inum->no_addr;
return 0;
}
struct inode *gfs2_ilookup(struct super_block *sb, struct gfs2_inum_host *inum)
{
return ilookup5(sb, (unsigned long)inum->no_addr,
iget_test, inum);
}
static struct inode *gfs2_iget(struct super_block *sb, struct gfs2_inum_host *inum)
{
return iget5_locked(sb, (unsigned long)inum->no_addr,
iget_test, iget_set, inum);
}
/**
* gfs2_inode_lookup - Lookup an inode
* @sb: The super block
* @inum: The inode number
* @type: The type of the inode
*
* Returns: A VFS inode, or an error
*/
struct inode *gfs2_inode_lookup(struct super_block *sb, struct gfs2_inum_host *inum, unsigned int type)
{
struct inode *inode = gfs2_iget(sb, inum);
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_glock *io_gl;
int error;
if (!inode)
return ERR_PTR(-ENOBUFS);
if (inode->i_state & I_NEW) {
struct gfs2_sbd *sdp = GFS2_SB(inode);
umode_t mode = DT2IF(type);
inode->i_private = ip;
inode->i_mode = mode;
if (S_ISREG(mode)) {
inode->i_op = &gfs2_file_iops;
inode->i_fop = &gfs2_file_fops;
inode->i_mapping->a_ops = &gfs2_file_aops;
} else if (S_ISDIR(mode)) {
inode->i_op = &gfs2_dir_iops;
inode->i_fop = &gfs2_dir_fops;
} else if (S_ISLNK(mode)) {
inode->i_op = &gfs2_symlink_iops;
} else {
inode->i_op = &gfs2_dev_iops;
}
error = gfs2_glock_get(sdp, inum->no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
if (unlikely(error))
goto fail;
ip->i_gl->gl_object = ip;
error = gfs2_glock_get(sdp, inum->no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
if (unlikely(error))
goto fail_put;
set_bit(GIF_INVALID, &ip->i_flags);
error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
if (unlikely(error))
goto fail_iopen;
gfs2_glock_put(io_gl);
unlock_new_inode(inode);
}
return inode;
fail_iopen:
gfs2_glock_put(io_gl);
fail_put:
ip->i_gl->gl_object = NULL;
gfs2_glock_put(ip->i_gl);
fail:
iput(inode);
return ERR_PTR(error);
}
static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf)
{
struct gfs2_dinode_host *di = &ip->i_di;
const struct gfs2_dinode *str = buf;
if (ip->i_num.no_addr != be64_to_cpu(str->di_num.no_addr)) {
if (gfs2_consist_inode(ip))
gfs2_dinode_print(ip);
return -EIO;
}
if (ip->i_num.no_formal_ino != be64_to_cpu(str->di_num.no_formal_ino))
return -ESTALE;
ip->i_inode.i_mode = be32_to_cpu(str->di_mode);
ip->i_inode.i_rdev = 0;
switch (ip->i_inode.i_mode & S_IFMT) {
case S_IFBLK:
case S_IFCHR:
ip->i_inode.i_rdev = MKDEV(be32_to_cpu(str->di_major),
be32_to_cpu(str->di_minor));
break;
};
ip->i_inode.i_uid = be32_to_cpu(str->di_uid);
ip->i_inode.i_gid = be32_to_cpu(str->di_gid);
/*
* We will need to review setting the nlink count here in the
* light of the forthcoming ro bind mount work. This is a reminder
* to do that.
*/
ip->i_inode.i_nlink = be32_to_cpu(str->di_nlink);
di->di_size = be64_to_cpu(str->di_size);
i_size_write(&ip->i_inode, di->di_size);
di->di_blocks = be64_to_cpu(str->di_blocks);
gfs2_set_inode_blocks(&ip->i_inode);
ip->i_inode.i_atime.tv_sec = be64_to_cpu(str->di_atime);
ip->i_inode.i_atime.tv_nsec = 0;
ip->i_inode.i_mtime.tv_sec = be64_to_cpu(str->di_mtime);
ip->i_inode.i_mtime.tv_nsec = 0;
ip->i_inode.i_ctime.tv_sec = be64_to_cpu(str->di_ctime);
ip->i_inode.i_ctime.tv_nsec = 0;
di->di_goal_meta = be64_to_cpu(str->di_goal_meta);
di->di_goal_data = be64_to_cpu(str->di_goal_data);
di->di_generation = be64_to_cpu(str->di_generation);
di->di_flags = be32_to_cpu(str->di_flags);
gfs2_set_inode_flags(&ip->i_inode);
di->di_height = be16_to_cpu(str->di_height);
di->di_depth = be16_to_cpu(str->di_depth);
di->di_entries = be32_to_cpu(str->di_entries);
di->di_eattr = be64_to_cpu(str->di_eattr);
return 0;
}
/**
* gfs2_inode_refresh - Refresh the incore copy of the dinode
* @ip: The GFS2 inode
*
* Returns: errno
*/
int gfs2_inode_refresh(struct gfs2_inode *ip)
{
struct buffer_head *dibh;
int error;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
return error;
if (gfs2_metatype_check(GFS2_SB(&ip->i_inode), dibh, GFS2_METATYPE_DI)) {
brelse(dibh);
return -EIO;
}
error = gfs2_dinode_in(ip, dibh->b_data);
brelse(dibh);
clear_bit(GIF_INVALID, &ip->i_flags);
return error;
}
int gfs2_dinode_dealloc(struct gfs2_inode *ip)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct gfs2_alloc *al;
struct gfs2_rgrpd *rgd;
int error;
if (ip->i_di.di_blocks != 1) {
if (gfs2_consist_inode(ip))
gfs2_dinode_print(ip);
return -EIO;
}
al = gfs2_alloc_get(ip);
error = gfs2_quota_hold(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
if (error)
goto out;
error = gfs2_rindex_hold(sdp, &al->al_ri_gh);
if (error)
goto out_qs;
rgd = gfs2_blk2rgrpd(sdp, ip->i_num.no_addr);
if (!rgd) {
gfs2_consist_inode(ip);
error = -EIO;
goto out_rindex_relse;
}
error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0,
&al->al_rgd_gh);
if (error)
goto out_rindex_relse;
error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA, 1);
if (error)
goto out_rg_gunlock;
gfs2_trans_add_gl(ip->i_gl);
gfs2_free_di(rgd, ip);
gfs2_trans_end(sdp);
clear_bit(GLF_STICKY, &ip->i_gl->gl_flags);
out_rg_gunlock:
gfs2_glock_dq_uninit(&al->al_rgd_gh);
out_rindex_relse:
gfs2_glock_dq_uninit(&al->al_ri_gh);
out_qs:
gfs2_quota_unhold(ip);
out:
gfs2_alloc_put(ip);
return error;
}
/**
* gfs2_change_nlink - Change nlink count on inode
* @ip: The GFS2 inode
* @diff: The change in the nlink count required
*
* Returns: errno
*/
int gfs2_change_nlink(struct gfs2_inode *ip, int diff)
{
struct buffer_head *dibh;
u32 nlink;
int error;
BUG_ON(diff != 1 && diff != -1);
nlink = ip->i_inode.i_nlink + diff;
/* If we are reducing the nlink count, but the new value ends up being
bigger than the old one, we must have underflowed. */
if (diff < 0 && nlink > ip->i_inode.i_nlink) {
if (gfs2_consist_inode(ip))
gfs2_dinode_print(ip);
return -EIO;
}
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
return error;
if (diff > 0)
inc_nlink(&ip->i_inode);
else
drop_nlink(&ip->i_inode);
ip->i_inode.i_ctime = CURRENT_TIME_SEC;
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
brelse(dibh);
mark_inode_dirty(&ip->i_inode);
if (ip->i_inode.i_nlink == 0)
gfs2_unlink_di(&ip->i_inode); /* mark inode unlinked */
return error;
}
struct inode *gfs2_lookup_simple(struct inode *dip, const char *name)
{
struct qstr qstr;
struct inode *inode;
gfs2_str2qstr(&qstr, name);
inode = gfs2_lookupi(dip, &qstr, 1, NULL);
/* gfs2_lookupi has inconsistent callers: vfs
* related routines expect NULL for no entry found,
* gfs2_lookup_simple callers expect ENOENT
* and do not check for NULL.
*/
if (inode == NULL)
return ERR_PTR(-ENOENT);
else
return inode;
}
/**
* gfs2_lookupi - Look up a filename in a directory and return its inode
* @d_gh: An initialized holder for the directory glock
* @name: The name of the inode to look for
* @is_root: If 1, ignore the caller's permissions
* @i_gh: An uninitialized holder for the new inode glock
*
* This can be called via the VFS filldir function when NFS is doing
* a readdirplus and the inode which its intending to stat isn't
* already in cache. In this case we must not take the directory glock
* again, since the readdir call will have already taken that lock.
*
* Returns: errno
*/
struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name,
int is_root, struct nameidata *nd)
{
struct super_block *sb = dir->i_sb;
struct gfs2_inode *dip = GFS2_I(dir);
struct gfs2_holder d_gh;
struct gfs2_inum_host inum;
unsigned int type;
int error;
struct inode *inode = NULL;
int unlock = 0;
if (!name->len || name->len > GFS2_FNAMESIZE)
return ERR_PTR(-ENAMETOOLONG);
if ((name->len == 1 && memcmp(name->name, ".", 1) == 0) ||
(name->len == 2 && memcmp(name->name, "..", 2) == 0 &&
dir == sb->s_root->d_inode)) {
igrab(dir);
return dir;
}
if (gfs2_glock_is_locked_by_me(dip->i_gl) == 0) {
error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh);
if (error)
return ERR_PTR(error);
unlock = 1;
}
if (!is_root) {
error = permission(dir, MAY_EXEC, NULL);
if (error)
goto out;
}
error = gfs2_dir_search(dir, name, &inum, &type);
if (error)
goto out;
inode = gfs2_inode_lookup(sb, &inum, type);
out:
if (unlock)
gfs2_glock_dq_uninit(&d_gh);
if (error == -ENOENT)
return NULL;
return inode ? inode : ERR_PTR(error);
}
static int pick_formal_ino_1(struct gfs2_sbd *sdp, u64 *formal_ino)
{
struct gfs2_inode *ip = GFS2_I(sdp->sd_ir_inode);
struct buffer_head *bh;
struct gfs2_inum_range_host ir;
int error;
error = gfs2_trans_begin(sdp, RES_DINODE, 0);
if (error)
return error;
mutex_lock(&sdp->sd_inum_mutex);
error = gfs2_meta_inode_buffer(ip, &bh);
if (error) {
mutex_unlock(&sdp->sd_inum_mutex);
gfs2_trans_end(sdp);
return error;
}
gfs2_inum_range_in(&ir, bh->b_data + sizeof(struct gfs2_dinode));
if (ir.ir_length) {
*formal_ino = ir.ir_start++;
ir.ir_length--;
gfs2_trans_add_bh(ip->i_gl, bh, 1);
gfs2_inum_range_out(&ir,
bh->b_data + sizeof(struct gfs2_dinode));
brelse(bh);
mutex_unlock(&sdp->sd_inum_mutex);
gfs2_trans_end(sdp);
return 0;
}
brelse(bh);
mutex_unlock(&sdp->sd_inum_mutex);
gfs2_trans_end(sdp);
return 1;
}
static int pick_formal_ino_2(struct gfs2_sbd *sdp, u64 *formal_ino)
{
struct gfs2_inode *ip = GFS2_I(sdp->sd_ir_inode);
struct gfs2_inode *m_ip = GFS2_I(sdp->sd_inum_inode);
struct gfs2_holder gh;
struct buffer_head *bh;
struct gfs2_inum_range_host ir;
int error;
error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
if (error)
return error;
error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
if (error)
goto out;
mutex_lock(&sdp->sd_inum_mutex);
error = gfs2_meta_inode_buffer(ip, &bh);
if (error)
goto out_end_trans;
gfs2_inum_range_in(&ir, bh->b_data + sizeof(struct gfs2_dinode));
if (!ir.ir_length) {
struct buffer_head *m_bh;
u64 x, y;
__be64 z;
error = gfs2_meta_inode_buffer(m_ip, &m_bh);
if (error)
goto out_brelse;
z = *(__be64 *)(m_bh->b_data + sizeof(struct gfs2_dinode));
x = y = be64_to_cpu(z);
ir.ir_start = x;
ir.ir_length = GFS2_INUM_QUANTUM;
x += GFS2_INUM_QUANTUM;
if (x < y)
gfs2_consist_inode(m_ip);
z = cpu_to_be64(x);
gfs2_trans_add_bh(m_ip->i_gl, m_bh, 1);
*(__be64 *)(m_bh->b_data + sizeof(struct gfs2_dinode)) = z;
brelse(m_bh);
}
*formal_ino = ir.ir_start++;
ir.ir_length--;
gfs2_trans_add_bh(ip->i_gl, bh, 1);
gfs2_inum_range_out(&ir, bh->b_data + sizeof(struct gfs2_dinode));
out_brelse:
brelse(bh);
out_end_trans:
mutex_unlock(&sdp->sd_inum_mutex);
gfs2_trans_end(sdp);
out:
gfs2_glock_dq_uninit(&gh);
return error;
}
static int pick_formal_ino(struct gfs2_sbd *sdp, u64 *inum)
{
int error;
error = pick_formal_ino_1(sdp, inum);
if (error <= 0)
return error;
error = pick_formal_ino_2(sdp, inum);
return error;
}
/**
* create_ok - OK to create a new on-disk inode here?
* @dip: Directory in which dinode is to be created
* @name: Name of new dinode
* @mode:
*
* Returns: errno
*/
static int create_ok(struct gfs2_inode *dip, const struct qstr *name,
unsigned int mode)
{
int error;
error = permission(&dip->i_inode, MAY_WRITE | MAY_EXEC, NULL);
if (error)
return error;
/* Don't create entries in an unlinked directory */
if (!dip->i_inode.i_nlink)
return -EPERM;
error = gfs2_dir_search(&dip->i_inode, name, NULL, NULL);
switch (error) {
case -ENOENT:
error = 0;
break;
case 0:
return -EEXIST;
default:
return error;
}
if (dip->i_di.di_entries == (u32)-1)
return -EFBIG;
if (S_ISDIR(mode) && dip->i_inode.i_nlink == (u32)-1)
return -EMLINK;
return 0;
}
static void munge_mode_uid_gid(struct gfs2_inode *dip, unsigned int *mode,
unsigned int *uid, unsigned int *gid)
{
if (GFS2_SB(&dip->i_inode)->sd_args.ar_suiddir &&
(dip->i_inode.i_mode & S_ISUID) && dip->i_inode.i_uid) {
if (S_ISDIR(*mode))
*mode |= S_ISUID;
else if (dip->i_inode.i_uid != current->fsuid)
*mode &= ~07111;
*uid = dip->i_inode.i_uid;
} else
*uid = current->fsuid;
if (dip->i_inode.i_mode & S_ISGID) {
if (S_ISDIR(*mode))
*mode |= S_ISGID;
*gid = dip->i_inode.i_gid;
} else
*gid = current->fsgid;
}
static int alloc_dinode(struct gfs2_inode *dip, struct gfs2_inum_host *inum,
u64 *generation)
{
struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
int error;
gfs2_alloc_get(dip);
dip->i_alloc.al_requested = RES_DINODE;
error = gfs2_inplace_reserve(dip);
if (error)
goto out;
error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS, 0);
if (error)
goto out_ipreserv;
inum->no_addr = gfs2_alloc_di(dip, generation);
gfs2_trans_end(sdp);
out_ipreserv:
gfs2_inplace_release(dip);
out:
gfs2_alloc_put(dip);
return error;
}
/**
* init_dinode - Fill in a new dinode structure
* @dip: the directory this inode is being created in
* @gl: The glock covering the new inode
* @inum: the inode number
* @mode: the file permissions
* @uid:
* @gid:
*
*/
static void init_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
const struct gfs2_inum_host *inum, unsigned int mode,
unsigned int uid, unsigned int gid,
const u64 *generation, dev_t dev)
{
struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
struct gfs2_dinode *di;
struct buffer_head *dibh;
dibh = gfs2_meta_new(gl, inum->no_addr);
gfs2_trans_add_bh(gl, dibh, 1);
gfs2_metatype_set(dibh, GFS2_METATYPE_DI, GFS2_FORMAT_DI);
gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
di = (struct gfs2_dinode *)dibh->b_data;
di->di_num.no_formal_ino = cpu_to_be64(inum->no_formal_ino);
di->di_num.no_addr = cpu_to_be64(inum->no_addr);
di->di_mode = cpu_to_be32(mode);
di->di_uid = cpu_to_be32(uid);
di->di_gid = cpu_to_be32(gid);
di->di_nlink = 0;
di->di_size = 0;
di->di_blocks = cpu_to_be64(1);
di->di_atime = di->di_mtime = di->di_ctime = cpu_to_be64(get_seconds());
di->di_major = cpu_to_be32(MAJOR(dev));
di->di_minor = cpu_to_be32(MINOR(dev));
di->di_goal_meta = di->di_goal_data = cpu_to_be64(inum->no_addr);
di->di_generation = cpu_to_be64(*generation);
di->di_flags = 0;
if (S_ISREG(mode)) {
if ((dip->i_di.di_flags & GFS2_DIF_INHERIT_JDATA) ||
gfs2_tune_get(sdp, gt_new_files_jdata))
di->di_flags |= cpu_to_be32(GFS2_DIF_JDATA);
if ((dip->i_di.di_flags & GFS2_DIF_INHERIT_DIRECTIO) ||
gfs2_tune_get(sdp, gt_new_files_directio))
di->di_flags |= cpu_to_be32(GFS2_DIF_DIRECTIO);
} else if (S_ISDIR(mode)) {
di->di_flags |= cpu_to_be32(dip->i_di.di_flags &
GFS2_DIF_INHERIT_DIRECTIO);
di->di_flags |= cpu_to_be32(dip->i_di.di_flags &
GFS2_DIF_INHERIT_JDATA);
}
di->__pad1 = 0;
di->di_payload_format = cpu_to_be32(S_ISDIR(mode) ? GFS2_FORMAT_DE : 0);
di->di_height = 0;
di->__pad2 = 0;
di->__pad3 = 0;
di->di_depth = 0;
di->di_entries = 0;
memset(&di->__pad4, 0, sizeof(di->__pad4));
di->di_eattr = 0;
memset(&di->di_reserved, 0, sizeof(di->di_reserved));
brelse(dibh);
}
static int make_dinode(struct gfs2_inode *dip, struct gfs2_glock *gl,
unsigned int mode, const struct gfs2_inum_host *inum,
const u64 *generation, dev_t dev)
{
struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
unsigned int uid, gid;
int error;
munge_mode_uid_gid(dip, &mode, &uid, &gid);
gfs2_alloc_get(dip);
error = gfs2_quota_lock(dip, uid, gid);
if (error)
goto out;
error = gfs2_quota_check(dip, uid, gid);
if (error)
goto out_quota;
error = gfs2_trans_begin(sdp, RES_DINODE + RES_QUOTA, 0);
if (error)
goto out_quota;
init_dinode(dip, gl, inum, mode, uid, gid, generation, dev);
gfs2_quota_change(dip, +1, uid, gid);
gfs2_trans_end(sdp);
out_quota:
gfs2_quota_unlock(dip);
out:
gfs2_alloc_put(dip);
return error;
}
static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
struct gfs2_inode *ip)
{
struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
struct gfs2_alloc *al;
int alloc_required;
struct buffer_head *dibh;
int error;
al = gfs2_alloc_get(dip);
error = gfs2_quota_lock(dip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
if (error)
goto fail;
error = alloc_required = gfs2_diradd_alloc_required(&dip->i_inode, name);
if (alloc_required < 0)
goto fail;
if (alloc_required) {
error = gfs2_quota_check(dip, dip->i_inode.i_uid, dip->i_inode.i_gid);
if (error)
goto fail_quota_locks;
al->al_requested = sdp->sd_max_dirres;
error = gfs2_inplace_reserve(dip);
if (error)
goto fail_quota_locks;
error = gfs2_trans_begin(sdp, sdp->sd_max_dirres +
al->al_rgd->rd_ri.ri_length +
2 * RES_DINODE +
RES_STATFS + RES_QUOTA, 0);
if (error)
goto fail_ipreserv;
} else {
error = gfs2_trans_begin(sdp, RES_LEAF + 2 * RES_DINODE, 0);
if (error)
goto fail_quota_locks;
}
error = gfs2_dir_add(&dip->i_inode, name, &ip->i_num, IF2DT(ip->i_inode.i_mode));
if (error)
goto fail_end_trans;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto fail_end_trans;
ip->i_inode.i_nlink = 1;
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
brelse(dibh);
return 0;
fail_end_trans:
gfs2_trans_end(sdp);
fail_ipreserv:
if (dip->i_alloc.al_rgd)
gfs2_inplace_release(dip);
fail_quota_locks:
gfs2_quota_unlock(dip);
fail:
gfs2_alloc_put(dip);
return error;
}
static int gfs2_security_init(struct gfs2_inode *dip, struct gfs2_inode *ip)
{
int err;
size_t len;
void *value;
char *name;
struct gfs2_ea_request er;
err = security_inode_init_security(&ip->i_inode, &dip->i_inode,
&name, &value, &len);
if (err) {
if (err == -EOPNOTSUPP)
return 0;
return err;
}
memset(&er, 0, sizeof(struct gfs2_ea_request));
er.er_type = GFS2_EATYPE_SECURITY;
er.er_name = name;
er.er_data = value;
er.er_name_len = strlen(name);
er.er_data_len = len;
err = gfs2_ea_set_i(ip, &er);
kfree(value);
kfree(name);
return err;
}
/**
* gfs2_createi - Create a new inode
* @ghs: An array of two holders
* @name: The name of the new file
* @mode: the permissions on the new inode
*
* @ghs[0] is an initialized holder for the directory
* @ghs[1] is the holder for the inode lock
*
* If the return value is not NULL, the glocks on both the directory and the new
* file are held. A transaction has been started and an inplace reservation
* is held, as well.
*
* Returns: An inode
*/
struct inode *gfs2_createi(struct gfs2_holder *ghs, const struct qstr *name,
unsigned int mode, dev_t dev)
{
struct inode *inode;
struct gfs2_inode *dip = ghs->gh_gl->gl_object;
struct inode *dir = &dip->i_inode;
struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
struct gfs2_inum_host inum;
int error;
u64 generation;
if (!name->len || name->len > GFS2_FNAMESIZE)
return ERR_PTR(-ENAMETOOLONG);
gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, ghs);
error = gfs2_glock_nq(ghs);
if (error)
goto fail;
error = create_ok(dip, name, mode);
if (error)
goto fail_gunlock;
error = pick_formal_ino(sdp, &inum.no_formal_ino);
if (error)
goto fail_gunlock;
error = alloc_dinode(dip, &inum, &generation);
if (error)
goto fail_gunlock;
error = gfs2_glock_nq_num(sdp, inum.no_addr, &gfs2_inode_glops,
LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
if (error)
goto fail_gunlock;
error = make_dinode(dip, ghs[1].gh_gl, mode, &inum, &generation, dev);
if (error)
goto fail_gunlock2;
inode = gfs2_inode_lookup(dir->i_sb, &inum, IF2DT(mode));
if (IS_ERR(inode))
goto fail_gunlock2;
error = gfs2_inode_refresh(GFS2_I(inode));
if (error)
goto fail_iput;
error = gfs2_acl_create(dip, GFS2_I(inode));
if (error)
goto fail_iput;
error = gfs2_security_init(dip, GFS2_I(inode));
if (error)
goto fail_iput;
error = link_dinode(dip, name, GFS2_I(inode));
if (error)
goto fail_iput;
if (!inode)
return ERR_PTR(-ENOMEM);
return inode;
fail_iput:
iput(inode);
fail_gunlock2:
gfs2_glock_dq_uninit(ghs + 1);
fail_gunlock:
gfs2_glock_dq(ghs);
fail:
return ERR_PTR(error);
}
/**
* gfs2_rmdiri - Remove a directory
* @dip: The parent directory of the directory to be removed
* @name: The name of the directory to be removed
* @ip: The GFS2 inode of the directory to be removed
*
* Assumes Glocks on dip and ip are held
*
* Returns: errno
*/
int gfs2_rmdiri(struct gfs2_inode *dip, const struct qstr *name,
struct gfs2_inode *ip)
{
struct qstr dotname;
int error;
if (ip->i_di.di_entries != 2) {
if (gfs2_consist_inode(ip))
gfs2_dinode_print(ip);
return -EIO;
}
error = gfs2_dir_del(dip, name);
if (error)
return error;
error = gfs2_change_nlink(dip, -1);
if (error)
return error;
gfs2_str2qstr(&dotname, ".");
error = gfs2_dir_del(ip, &dotname);
if (error)
return error;
gfs2_str2qstr(&dotname, "..");
error = gfs2_dir_del(ip, &dotname);
if (error)
return error;
/* It looks odd, but it really should be done twice */
error = gfs2_change_nlink(ip, -1);
if (error)
return error;
error = gfs2_change_nlink(ip, -1);
if (error)
return error;
return error;
}
/*
* gfs2_unlink_ok - check to see that a inode is still in a directory
* @dip: the directory
* @name: the name of the file
* @ip: the inode
*
* Assumes that the lock on (at least) @dip is held.
*
* Returns: 0 if the parent/child relationship is correct, errno if it isn't
*/
int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
struct gfs2_inode *ip)
{
struct gfs2_inum_host inum;
unsigned int type;
int error;
if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
return -EPERM;
if ((dip->i_inode.i_mode & S_ISVTX) &&
dip->i_inode.i_uid != current->fsuid &&
ip->i_inode.i_uid != current->fsuid && !capable(CAP_FOWNER))
return -EPERM;
if (IS_APPEND(&dip->i_inode))
return -EPERM;
error = permission(&dip->i_inode, MAY_WRITE | MAY_EXEC, NULL);
if (error)
return error;
error = gfs2_dir_search(&dip->i_inode, name, &inum, &type);
if (error)
return error;
if (!gfs2_inum_equal(&inum, &ip->i_num))
return -ENOENT;
if (IF2DT(ip->i_inode.i_mode) != type) {
gfs2_consist_inode(dip);
return -EIO;
}
return 0;
}
/*
* gfs2_ok_to_move - check if it's ok to move a directory to another directory
* @this: move this
* @to: to here
*
* Follow @to back to the root and make sure we don't encounter @this
* Assumes we already hold the rename lock.
*
* Returns: errno
*/
int gfs2_ok_to_move(struct gfs2_inode *this, struct gfs2_inode *to)
{
struct inode *dir = &to->i_inode;
struct super_block *sb = dir->i_sb;
struct inode *tmp;
struct qstr dotdot;
int error = 0;
gfs2_str2qstr(&dotdot, "..");
igrab(dir);
for (;;) {
if (dir == &this->i_inode) {
error = -EINVAL;
break;
}
if (dir == sb->s_root->d_inode) {
error = 0;
break;
}
tmp = gfs2_lookupi(dir, &dotdot, 1, NULL);
if (IS_ERR(tmp)) {
error = PTR_ERR(tmp);
break;
}
iput(dir);
dir = tmp;
}
iput(dir);
return error;
}
/**
* gfs2_readlinki - return the contents of a symlink
* @ip: the symlink's inode
* @buf: a pointer to the buffer to be filled
* @len: a pointer to the length of @buf
*
* If @buf is too small, a piece of memory is kmalloc()ed and needs
* to be freed by the caller.
*
* Returns: errno
*/
int gfs2_readlinki(struct gfs2_inode *ip, char **buf, unsigned int *len)
{
struct gfs2_holder i_gh;
struct buffer_head *dibh;
unsigned int x;
int error;
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &i_gh);
error = gfs2_glock_nq_atime(&i_gh);
if (error) {
gfs2_holder_uninit(&i_gh);
return error;
}
if (!ip->i_di.di_size) {
gfs2_consist_inode(ip);
error = -EIO;
goto out;
}
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto out;
x = ip->i_di.di_size + 1;
if (x > *len) {
*buf = kmalloc(x, GFP_KERNEL);
if (!*buf) {
error = -ENOMEM;
goto out_brelse;
}
}
memcpy(*buf, dibh->b_data + sizeof(struct gfs2_dinode), x);
*len = x;
out_brelse:
brelse(dibh);
out:
gfs2_glock_dq_uninit(&i_gh);
return error;
}
/**
* gfs2_glock_nq_atime - Acquire a hold on an inode's glock, and
* conditionally update the inode's atime
* @gh: the holder to acquire
*
* Tests atime (access time) for gfs2_read, gfs2_readdir and gfs2_mmap
* Update if the difference between the current time and the inode's current
* atime is greater than an interval specified at mount.
*
* Returns: errno
*/
int gfs2_glock_nq_atime(struct gfs2_holder *gh)
{
struct gfs2_glock *gl = gh->gh_gl;
struct gfs2_sbd *sdp = gl->gl_sbd;
struct gfs2_inode *ip = gl->gl_object;
s64 curtime, quantum = gfs2_tune_get(sdp, gt_atime_quantum);
unsigned int state;
int flags;
int error;
if (gfs2_assert_warn(sdp, gh->gh_flags & GL_ATIME) ||
gfs2_assert_warn(sdp, !(gh->gh_flags & GL_ASYNC)) ||
gfs2_assert_warn(sdp, gl->gl_ops == &gfs2_inode_glops))
return -EINVAL;
state = gh->gh_state;
flags = gh->gh_flags;
error = gfs2_glock_nq(gh);
if (error)
return error;
if (test_bit(SDF_NOATIME, &sdp->sd_flags) ||
(sdp->sd_vfs->s_flags & MS_RDONLY))
return 0;
curtime = get_seconds();
if (curtime - ip->i_inode.i_atime.tv_sec >= quantum) {
gfs2_glock_dq(gh);
gfs2_holder_reinit(LM_ST_EXCLUSIVE, gh->gh_flags & ~LM_FLAG_ANY,
gh);
error = gfs2_glock_nq(gh);
if (error)
return error;
/* Verify that atime hasn't been updated while we were
trying to get exclusive lock. */
curtime = get_seconds();
if (curtime - ip->i_inode.i_atime.tv_sec >= quantum) {
struct buffer_head *dibh;
struct gfs2_dinode *di;
error = gfs2_trans_begin(sdp, RES_DINODE, 0);
if (error == -EROFS)
return 0;
if (error)
goto fail;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto fail_end_trans;
ip->i_inode.i_atime.tv_sec = curtime;
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
di = (struct gfs2_dinode *)dibh->b_data;
di->di_atime = cpu_to_be64(ip->i_inode.i_atime.tv_sec);
brelse(dibh);
gfs2_trans_end(sdp);
}
/* If someone else has asked for the glock,
unlock and let them have it. Then reacquire
in the original state. */
if (gfs2_glock_is_blocking(gl)) {
gfs2_glock_dq(gh);
gfs2_holder_reinit(state, flags, gh);
return gfs2_glock_nq(gh);
}
}
return 0;
fail_end_trans:
gfs2_trans_end(sdp);
fail:
gfs2_glock_dq(gh);
return error;
}
static int
__gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr)
{
struct buffer_head *dibh;
int error;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (!error) {
error = inode_setattr(&ip->i_inode, attr);
gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error);
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
gfs2_dinode_out(ip, dibh->b_data);
brelse(dibh);
}
return error;
}
/**
* gfs2_setattr_simple -
* @ip:
* @attr:
*
* Called with a reference on the vnode.
*
* Returns: errno
*/
int gfs2_setattr_simple(struct gfs2_inode *ip, struct iattr *attr)
{
int error;
if (current->journal_info)
return __gfs2_setattr_simple(ip, attr);
error = gfs2_trans_begin(GFS2_SB(&ip->i_inode), RES_DINODE, 0);
if (error)
return error;
error = __gfs2_setattr_simple(ip, attr);
gfs2_trans_end(GFS2_SB(&ip->i_inode));
return error;
}