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3ce37b2cb4
linux/fs/gfs2/inode.c
Andreas Gruenbacher 3ce37b2cb4 gfs2: Fix gfs2_lookup_by_inum lock inversion 
The current gfs2_lookup_by_inum takes the glock of a presumed inode
identified by block number, verifies that the block is indeed an inode,
and then instantiates and reads the new inode via gfs2_inode_lookup.

However, instantiating a new inode may block on freeing a previous
instance of that inode (__wait_on_freeing_inode), and freeing an inode
requires to take the glock already held, leading to lock inversion and
deadlock.

Fix this by first instantiating the new inode, then verifying that the
block is an inode (if required), and then reading in the new inode, all
in gfs2_inode_lookup.

If the block we are looking for is not an inode, we discard the new
inode via iget_failed, which marks inodes as bad and unhashes them.
Other tasks waiting on that inode will get back a bad inode back from
ilookup or iget_locked; in that case, retry the lookup.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-06-27 09:47:07 -05:00

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/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2011 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/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/namei.h>
#include <linux/mm.h>
#include <linux/xattr.h>
#include <linux/posix_acl.h>
#include <linux/gfs2_ondisk.h>
#include <linux/crc32.h>
#include <linux/fiemap.h>
#include <linux/security.h>
#include <asm/uaccess.h>
#include "gfs2.h"
#include "incore.h"
#include "acl.h"
#include "bmap.h"
#include "dir.h"
#include "xattr.h"
#include "glock.h"
#include "inode.h"
#include "meta_io.h"
#include "quota.h"
#include "rgrp.h"
#include "trans.h"
#include "util.h"
#include "super.h"
#include "glops.h"
struct inode *gfs2_ilookup(struct super_block *sb, u64 no_addr)
{
struct inode *inode;
repeat:
inode = ilookup(sb, no_addr);
if (!inode)
return inode;
if (is_bad_inode(inode)) {
iput(inode);
goto repeat;
}
return inode;
}
static struct inode *gfs2_iget(struct super_block *sb, u64 no_addr)
{
struct inode *inode;
repeat:
inode = iget_locked(sb, no_addr);
if (!inode)
return inode;
if (is_bad_inode(inode)) {
iput(inode);
goto repeat;
}
GFS2_I(inode)->i_no_addr = no_addr;
return inode;
}
/**
* gfs2_set_iop - Sets inode operations
* @inode: The inode with correct i_mode filled in
*
* GFS2 lookup code fills in vfs inode contents based on info obtained
* from directory entry inside gfs2_inode_lookup().
*/
static void gfs2_set_iop(struct inode *inode)
{
struct gfs2_sbd *sdp = GFS2_SB(inode);
umode_t mode = inode->i_mode;
if (S_ISREG(mode)) {
inode->i_op = &gfs2_file_iops;
if (gfs2_localflocks(sdp))
inode->i_fop = &gfs2_file_fops_nolock;
else
inode->i_fop = &gfs2_file_fops;
} else if (S_ISDIR(mode)) {
inode->i_op = &gfs2_dir_iops;
if (gfs2_localflocks(sdp))
inode->i_fop = &gfs2_dir_fops_nolock;
else
inode->i_fop = &gfs2_dir_fops;
} else if (S_ISLNK(mode)) {
inode->i_op = &gfs2_symlink_iops;
} else {
inode->i_op = &gfs2_file_iops;
init_special_inode(inode, inode->i_mode, inode->i_rdev);
}
}
/**
* gfs2_inode_lookup - Lookup an inode
* @sb: The super block
* @type: The type of the inode
* @no_addr: The inode number
* @no_formal_ino: The inode generation number
* @blktype: Requested block type (GFS2_BLKST_DINODE or GFS2_BLKST_UNLINKED;
* GFS2_BLKST_FREE do indicate not to verify)
*
* If @type is DT_UNKNOWN, the inode type is fetched from disk.
*
* If @blktype is anything other than GFS2_BLKST_FREE (which is used as a
* placeholder because it doesn't otherwise make sense), the on-disk block type
* is verified to be @blktype.
*
* Returns: A VFS inode, or an error
*/
struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
u64 no_addr, u64 no_formal_ino,
unsigned int blktype)
{
struct inode *inode;
struct gfs2_inode *ip;
struct gfs2_glock *io_gl = NULL;
struct gfs2_holder i_gh;
bool unlock = false;
int error;
inode = gfs2_iget(sb, no_addr);
if (!inode)
return ERR_PTR(-ENOMEM);
ip = GFS2_I(inode);
if (inode->i_state & I_NEW) {
struct gfs2_sbd *sdp = GFS2_SB(inode);
ip->i_no_formal_ino = no_formal_ino;
error = gfs2_glock_get(sdp, 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, no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
if (unlikely(error))
goto fail_put;
if (type == DT_UNKNOWN || blktype != GFS2_BLKST_FREE) {
/*
* The GL_SKIP flag indicates to skip reading the inode
* block. We read the inode with gfs2_inode_refresh
* after possibly checking the block type.
*/
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE,
GL_SKIP, &i_gh);
if (error)
goto fail_put;
unlock = true;
if (blktype != GFS2_BLKST_FREE) {
error = gfs2_check_blk_type(sdp, no_addr,
blktype);
if (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_put;
ip->i_iopen_gh.gh_gl->gl_object = ip;
gfs2_glock_put(io_gl);
io_gl = NULL;
if (type == DT_UNKNOWN) {
/* Inode glock must be locked already */
error = gfs2_inode_refresh(GFS2_I(inode));
if (error)
goto fail_refresh;
} else {
inode->i_mode = DT2IF(type);
}
gfs2_set_iop(inode);
unlock_new_inode(inode);
}
if (unlock)
gfs2_glock_dq_uninit(&i_gh);
return inode;
fail_refresh:
ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
ip->i_iopen_gh.gh_gl->gl_object = NULL;
gfs2_glock_dq_wait(&ip->i_iopen_gh);
gfs2_holder_uninit(&ip->i_iopen_gh);
fail_put:
if (io_gl)
gfs2_glock_put(io_gl);
if (unlock)
gfs2_glock_dq_uninit(&i_gh);
ip->i_gl->gl_object = NULL;
fail:
iget_failed(inode);
return ERR_PTR(error);
}
struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
u64 *no_formal_ino, unsigned int blktype)
{
struct super_block *sb = sdp->sd_vfs;
struct inode *inode;
int error;
inode = gfs2_inode_lookup(sb, DT_UNKNOWN, no_addr, 0, blktype);
if (IS_ERR(inode))
return inode;
/* Two extra checks for NFS only */
if (no_formal_ino) {
error = -ESTALE;
if (GFS2_I(inode)->i_no_formal_ino != *no_formal_ino)
goto fail_iput;
error = -EIO;
if (GFS2_I(inode)->i_diskflags & GFS2_DIF_SYSTEM)
goto fail_iput;
}
return inode;
fail_iput:
iput(inode);
return ERR_PTR(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);
/* 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 super_block *sb = dir->i_sb;
struct gfs2_inode *dip = GFS2_I(dir);
struct gfs2_holder d_gh;
int error = 0;
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 == d_inode(sb->s_root))) {
igrab(dir);
return dir;
}
if (gfs2_glock_is_locked_by_me(dip->i_gl) == NULL) {
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 = gfs2_permission(dir, MAY_EXEC);
if (error)
goto out;
}
inode = gfs2_dir_search(dir, name, false);
if (IS_ERR(inode))
error = PTR_ERR(inode);
out:
if (unlock)
gfs2_glock_dq_uninit(&d_gh);
if (error == -ENOENT)
return NULL;
return inode ? inode : ERR_PTR(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,
umode_t mode)
{
int error;
error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
if (error)
return error;
/* Don't create entries in an unlinked directory */
if (!dip->i_inode.i_nlink)
return -ENOENT;
if (dip->i_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(const struct gfs2_inode *dip,
struct inode *inode)
{
if (GFS2_SB(&dip->i_inode)->sd_args.ar_suiddir &&
(dip->i_inode.i_mode & S_ISUID) &&
!uid_eq(dip->i_inode.i_uid, GLOBAL_ROOT_UID)) {
if (S_ISDIR(inode->i_mode))
inode->i_mode |= S_ISUID;
else if (!uid_eq(dip->i_inode.i_uid, current_fsuid()))
inode->i_mode &= ~07111;
inode->i_uid = dip->i_inode.i_uid;
} else
inode->i_uid = current_fsuid();
if (dip->i_inode.i_mode & S_ISGID) {
if (S_ISDIR(inode->i_mode))
inode->i_mode |= S_ISGID;
inode->i_gid = dip->i_inode.i_gid;
} else
inode->i_gid = current_fsgid();
}
static int alloc_dinode(struct gfs2_inode *ip, u32 flags, unsigned *dblocks)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct gfs2_alloc_parms ap = { .target = *dblocks, .aflags = flags, };
int error;
error = gfs2_quota_lock_check(ip, &ap);
if (error)
goto out;
error = gfs2_inplace_reserve(ip, &ap);
if (error)
goto out_quota;
error = gfs2_trans_begin(sdp, (*dblocks * RES_RG_BIT) + RES_STATFS + RES_QUOTA, 0);
if (error)
goto out_ipreserv;
error = gfs2_alloc_blocks(ip, &ip->i_no_addr, dblocks, 1, &ip->i_generation);
ip->i_no_formal_ino = ip->i_generation;
ip->i_inode.i_ino = ip->i_no_addr;
ip->i_goal = ip->i_no_addr;
gfs2_trans_end(sdp);
out_ipreserv:
gfs2_inplace_release(ip);
out_quota:
gfs2_quota_unlock(ip);
out:
return error;
}
static void gfs2_init_dir(struct buffer_head *dibh,
const struct gfs2_inode *parent)
{
struct gfs2_dinode *di = (struct gfs2_dinode *)dibh->b_data;
struct gfs2_dirent *dent = (struct gfs2_dirent *)(di+1);
gfs2_qstr2dirent(&gfs2_qdot, GFS2_DIRENT_SIZE(gfs2_qdot.len), dent);
dent->de_inum = di->di_num; /* already GFS2 endian */
dent->de_type = cpu_to_be16(DT_DIR);
dent = (struct gfs2_dirent *)((char*)dent + GFS2_DIRENT_SIZE(1));
gfs2_qstr2dirent(&gfs2_qdotdot, dibh->b_size - GFS2_DIRENT_SIZE(1) - sizeof(struct gfs2_dinode), dent);
gfs2_inum_out(parent, dent);
dent->de_type = cpu_to_be16(DT_DIR);
}
/**
* gfs2_init_xattr - Initialise an xattr block for a new inode
* @ip: The inode in question
*
* This sets up an empty xattr block for a new inode, ready to
* take any ACLs, LSM xattrs, etc.
*/
static void gfs2_init_xattr(struct gfs2_inode *ip)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct buffer_head *bh;
struct gfs2_ea_header *ea;
bh = gfs2_meta_new(ip->i_gl, ip->i_eattr);
gfs2_trans_add_meta(ip->i_gl, bh);
gfs2_metatype_set(bh, GFS2_METATYPE_EA, GFS2_FORMAT_EA);
gfs2_buffer_clear_tail(bh, sizeof(struct gfs2_meta_header));
ea = GFS2_EA_BH2FIRST(bh);
ea->ea_rec_len = cpu_to_be32(sdp->sd_jbsize);
ea->ea_type = GFS2_EATYPE_UNUSED;
ea->ea_flags = GFS2_EAFLAG_LAST;
brelse(bh);
}
/**
* init_dinode - Fill in a new dinode structure
* @dip: The directory this inode is being created in
* @ip: The inode
* @symname: The symlink destination (if a symlink)
* @bhp: The buffer head (returned to caller)
*
*/
static void init_dinode(struct gfs2_inode *dip, struct gfs2_inode *ip,
const char *symname)
{
struct gfs2_dinode *di;
struct buffer_head *dibh;
dibh = gfs2_meta_new(ip->i_gl, ip->i_no_addr);
gfs2_trans_add_meta(ip->i_gl, dibh);
di = (struct gfs2_dinode *)dibh->b_data;
gfs2_dinode_out(ip, di);
di->di_major = cpu_to_be32(MAJOR(ip->i_inode.i_rdev));
di->di_minor = cpu_to_be32(MINOR(ip->i_inode.i_rdev));
di->__pad1 = 0;
di->__pad2 = 0;
di->__pad3 = 0;
memset(&di->__pad4, 0, sizeof(di->__pad4));
memset(&di->di_reserved, 0, sizeof(di->di_reserved));
gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode));
switch(ip->i_inode.i_mode & S_IFMT) {
case S_IFDIR:
gfs2_init_dir(dibh, dip);
break;
case S_IFLNK:
memcpy(dibh->b_data + sizeof(struct gfs2_dinode), symname, ip->i_inode.i_size);
break;
}
set_buffer_uptodate(dibh);
brelse(dibh);
}
/**
* gfs2_trans_da_blocks - Calculate number of blocks to link inode
* @dip: The directory we are linking into
* @da: The dir add information
* @nr_inodes: The number of inodes involved
*
* This calculate the number of blocks we need to reserve in a
* transaction to link @nr_inodes into a directory. In most cases
* @nr_inodes will be 2 (the directory plus the inode being linked in)
* but in case of rename, 4 may be required.
*
* Returns: Number of blocks
*/
static unsigned gfs2_trans_da_blks(const struct gfs2_inode *dip,
const struct gfs2_diradd *da,
unsigned nr_inodes)
{
return da->nr_blocks + gfs2_rg_blocks(dip, da->nr_blocks) +
(nr_inodes * RES_DINODE) + RES_QUOTA + RES_STATFS;
}
static int link_dinode(struct gfs2_inode *dip, const struct qstr *name,
struct gfs2_inode *ip, struct gfs2_diradd *da)
{
struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
struct gfs2_alloc_parms ap = { .target = da->nr_blocks, };
int error;
if (da->nr_blocks) {
error = gfs2_quota_lock_check(dip, &ap);
if (error)
goto fail_quota_locks;
error = gfs2_inplace_reserve(dip, &ap);
if (error)
goto fail_quota_locks;
error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, da, 2), 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, da);
gfs2_trans_end(sdp);
fail_ipreserv:
gfs2_inplace_release(dip);
fail_quota_locks:
gfs2_quota_unlock(dip);
return error;
}
static int gfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array,
void *fs_info)
{
const struct xattr *xattr;
int err = 0;
for (xattr = xattr_array; xattr->name != NULL; xattr++) {
err = __gfs2_xattr_set(inode, xattr->name, xattr->value,
xattr->value_len, 0,
GFS2_EATYPE_SECURITY);
if (err < 0)
break;
}
return err;
}
/**
* gfs2_create_inode - Create a new inode
* @dir: The parent directory
* @dentry: The new dentry
* @file: If non-NULL, the file which is being opened
* @mode: The permissions on the new inode
* @dev: For device nodes, this is the device number
* @symname: For symlinks, this is the link destination
* @size: The initial size of the inode (ignored for directories)
*
* Returns: 0 on success, or error code
*/
static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
struct file *file,
umode_t mode, dev_t dev, const char *symname,
unsigned int size, int excl, int *opened)
{
const struct qstr *name = &dentry->d_name;
struct posix_acl *default_acl, *acl;
struct gfs2_holder ghs[2];
struct inode *inode = NULL;
struct gfs2_inode *dip = GFS2_I(dir), *ip;
struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode);
struct gfs2_glock *io_gl = NULL;
int error, free_vfs_inode = 1;
u32 aflags = 0;
unsigned blocks = 1;
struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
if (!name->len || name->len > GFS2_FNAMESIZE)
return -ENAMETOOLONG;
error = gfs2_rsqa_alloc(dip);
if (error)
return error;
error = gfs2_rindex_update(sdp);
if (error)
return error;
error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
if (error)
goto fail;
error = create_ok(dip, name, mode);
if (error)
goto fail_gunlock;
inode = gfs2_dir_search(dir, &dentry->d_name, !S_ISREG(mode) || excl);
error = PTR_ERR(inode);
if (!IS_ERR(inode)) {
if (S_ISDIR(inode->i_mode)) {
iput(inode);
inode = ERR_PTR(-EISDIR);
goto fail_gunlock;
}
d_instantiate(dentry, inode);
error = 0;
if (file) {
if (S_ISREG(inode->i_mode))
error = finish_open(file, dentry, gfs2_open_common, opened);
else
error = finish_no_open(file, NULL);
}
gfs2_glock_dq_uninit(ghs);
return error;
} else if (error != -ENOENT) {
goto fail_gunlock;
}
error = gfs2_diradd_alloc_required(dir, name, &da);
if (error < 0)
goto fail_gunlock;
inode = new_inode(sdp->sd_vfs);
error = -ENOMEM;
if (!inode)
goto fail_gunlock;
error = posix_acl_create(dir, &mode, &default_acl, &acl);
if (error)
goto fail_gunlock;
ip = GFS2_I(inode);
error = gfs2_rsqa_alloc(ip);
if (error)
goto fail_free_acls;
inode->i_mode = mode;
set_nlink(inode, S_ISDIR(mode) ? 2 : 1);
inode->i_rdev = dev;
inode->i_size = size;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
gfs2_set_inode_blocks(inode, 1);
munge_mode_uid_gid(dip, inode);
check_and_update_goal(dip);
ip->i_goal = dip->i_goal;
ip->i_diskflags = 0;
ip->i_eattr = 0;
ip->i_height = 0;
ip->i_depth = 0;
ip->i_entries = 0;
switch(mode & S_IFMT) {
case S_IFREG:
if ((dip->i_diskflags & GFS2_DIF_INHERIT_JDATA) ||
gfs2_tune_get(sdp, gt_new_files_jdata))
ip->i_diskflags |= GFS2_DIF_JDATA;
gfs2_set_aops(inode);
break;
case S_IFDIR:
ip->i_diskflags |= (dip->i_diskflags & GFS2_DIF_INHERIT_JDATA);
ip->i_diskflags |= GFS2_DIF_JDATA;
ip->i_entries = 2;
break;
}
/* Force SYSTEM flag on all files and subdirs of a SYSTEM directory */
if (dip->i_diskflags & GFS2_DIF_SYSTEM)
ip->i_diskflags |= GFS2_DIF_SYSTEM;
gfs2_set_inode_flags(inode);
if ((GFS2_I(d_inode(sdp->sd_root_dir)) == dip) ||
(dip->i_diskflags & GFS2_DIF_TOPDIR))
aflags |= GFS2_AF_ORLOV;
if (default_acl || acl)
blocks++;
error = alloc_dinode(ip, aflags, &blocks);
if (error)
goto fail_free_inode;
gfs2_set_inode_blocks(inode, blocks);
error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
if (error)
goto fail_free_inode;
ip->i_gl->gl_object = ip;
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
if (error)
goto fail_free_inode;
error = gfs2_trans_begin(sdp, blocks, 0);
if (error)
goto fail_gunlock2;
if (blocks > 1) {
ip->i_eattr = ip->i_no_addr + 1;
gfs2_init_xattr(ip);
}
init_dinode(dip, ip, symname);
gfs2_trans_end(sdp);
error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
if (error)
goto fail_gunlock2;
BUG_ON(test_and_set_bit(GLF_INODE_CREATING, &io_gl->gl_flags));
error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
if (error)
goto fail_gunlock2;
ip->i_iopen_gh.gh_gl->gl_object = ip;
gfs2_glock_put(io_gl);
gfs2_set_iop(inode);
insert_inode_hash(inode);
free_vfs_inode = 0; /* After this point, the inode is no longer
considered free. Any failures need to undo
the gfs2 structures. */
if (default_acl) {
error = __gfs2_set_acl(inode, default_acl, ACL_TYPE_DEFAULT);
posix_acl_release(default_acl);
}
if (acl) {
if (!error)
error = __gfs2_set_acl(inode, acl, ACL_TYPE_ACCESS);
posix_acl_release(acl);
}
if (error)
goto fail_gunlock3;
error = security_inode_init_security(&ip->i_inode, &dip->i_inode, name,
&gfs2_initxattrs, NULL);
if (error)
goto fail_gunlock3;
error = link_dinode(dip, name, ip, &da);
if (error)
goto fail_gunlock3;
mark_inode_dirty(inode);
d_instantiate(dentry, inode);
if (file) {
*opened |= FILE_CREATED;
error = finish_open(file, dentry, gfs2_open_common, opened);
}
gfs2_glock_dq_uninit(ghs);
gfs2_glock_dq_uninit(ghs + 1);
clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
return error;
fail_gunlock3:
gfs2_glock_dq_uninit(&ip->i_iopen_gh);
gfs2_glock_put(io_gl);
fail_gunlock2:
if (io_gl)
clear_bit(GLF_INODE_CREATING, &io_gl->gl_flags);
gfs2_glock_dq_uninit(ghs + 1);
fail_free_inode:
if (ip->i_gl)
gfs2_glock_put(ip->i_gl);
gfs2_rsqa_delete(ip, NULL);
fail_free_acls:
if (default_acl)
posix_acl_release(default_acl);
if (acl)
posix_acl_release(acl);
fail_gunlock:
gfs2_dir_no_add(&da);
gfs2_glock_dq_uninit(ghs);
if (inode && !IS_ERR(inode)) {
clear_nlink(inode);
if (!free_vfs_inode)
mark_inode_dirty(inode);
set_bit(free_vfs_inode ? GIF_FREE_VFS_INODE : GIF_ALLOC_FAILED,
&GFS2_I(inode)->i_flags);
iput(inode);
}
fail:
return error;
}
/**
* gfs2_create - Create a file
* @dir: The directory in which to create the file
* @dentry: The dentry of the new file
* @mode: The mode of the new file
*
* Returns: errno
*/
static int gfs2_create(struct inode *dir, struct dentry *dentry,
umode_t mode, bool excl)
{
return gfs2_create_inode(dir, dentry, NULL, S_IFREG | mode, 0, NULL, 0, excl, NULL);
}
/**
* __gfs2_lookup - Look up a filename in a directory and return its inode
* @dir: The directory inode
* @dentry: The dentry of the new inode
* @file: File to be opened
* @opened: atomic_open flags
*
*
* Returns: errno
*/
static struct dentry *__gfs2_lookup(struct inode *dir, struct dentry *dentry,
struct file *file, int *opened)
{
struct inode *inode;
struct dentry *d;
struct gfs2_holder gh;
struct gfs2_glock *gl;
int error;
inode = gfs2_lookupi(dir, &dentry->d_name, 0);
if (inode == NULL) {
d_add(dentry, NULL);
return NULL;
}
if (IS_ERR(inode))
return ERR_CAST(inode);
gl = GFS2_I(inode)->i_gl;
error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
if (error) {
iput(inode);
return ERR_PTR(error);
}
d = d_splice_alias(inode, dentry);
if (IS_ERR(d)) {
gfs2_glock_dq_uninit(&gh);
return d;
}
if (file && S_ISREG(inode->i_mode))
error = finish_open(file, dentry, gfs2_open_common, opened);
gfs2_glock_dq_uninit(&gh);
if (error) {
dput(d);
return ERR_PTR(error);
}
return d;
}
static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
unsigned flags)
{
return __gfs2_lookup(dir, dentry, NULL, NULL);
}
/**
* gfs2_link - Link to a file
* @old_dentry: The inode to link
* @dir: Add link to this directory
* @dentry: The name of the link
*
* Link the inode in "old_dentry" into the directory "dir" with the
* name in "dentry".
*
* Returns: errno
*/
static int gfs2_link(struct dentry *old_dentry, struct inode *dir,
struct dentry *dentry)
{
struct gfs2_inode *dip = GFS2_I(dir);
struct gfs2_sbd *sdp = GFS2_SB(dir);
struct inode *inode = d_inode(old_dentry);
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder ghs[2];
struct buffer_head *dibh;
struct gfs2_diradd da = { .bh = NULL, .save_loc = 1, };
int error;
if (S_ISDIR(inode->i_mode))
return -EPERM;
error = gfs2_rsqa_alloc(dip);
if (error)
return error;
gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
error = gfs2_glock_nq(ghs); /* parent */
if (error)
goto out_parent;
error = gfs2_glock_nq(ghs + 1); /* child */
if (error)
goto out_child;
error = -ENOENT;
if (inode->i_nlink == 0)
goto out_gunlock;
error = gfs2_permission(dir, MAY_WRITE | MAY_EXEC);
if (error)
goto out_gunlock;
error = gfs2_dir_check(dir, &dentry->d_name, NULL);
switch (error) {
case -ENOENT:
break;
case 0:
error = -EEXIST;
default:
goto out_gunlock;
}
error = -EINVAL;
if (!dip->i_inode.i_nlink)
goto out_gunlock;
error = -EFBIG;
if (dip->i_entries == (u32)-1)
goto out_gunlock;
error = -EPERM;
if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
goto out_gunlock;
error = -EINVAL;
if (!ip->i_inode.i_nlink)
goto out_gunlock;
error = -EMLINK;
if (ip->i_inode.i_nlink == (u32)-1)
goto out_gunlock;
error = gfs2_diradd_alloc_required(dir, &dentry->d_name, &da);
if (error < 0)
goto out_gunlock;
if (da.nr_blocks) {
struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
error = gfs2_quota_lock_check(dip, &ap);
if (error)
goto out_gunlock;
error = gfs2_inplace_reserve(dip, &ap);
if (error)
goto out_gunlock_q;
error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(dip, &da, 2), 0);
if (error)
goto out_ipres;
} else {
error = gfs2_trans_begin(sdp, 2 * RES_DINODE + RES_LEAF, 0);
if (error)
goto out_ipres;
}
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto out_end_trans;
error = gfs2_dir_add(dir, &dentry->d_name, ip, &da);
if (error)
goto out_brelse;
gfs2_trans_add_meta(ip->i_gl, dibh);
inc_nlink(&ip->i_inode);
ip->i_inode.i_ctime = CURRENT_TIME;
ihold(inode);
d_instantiate(dentry, inode);
mark_inode_dirty(inode);
out_brelse:
brelse(dibh);
out_end_trans:
gfs2_trans_end(sdp);
out_ipres:
if (da.nr_blocks)
gfs2_inplace_release(dip);
out_gunlock_q:
if (da.nr_blocks)
gfs2_quota_unlock(dip);
out_gunlock:
gfs2_dir_no_add(&da);
gfs2_glock_dq(ghs + 1);
out_child:
gfs2_glock_dq(ghs);
out_parent:
gfs2_holder_uninit(ghs);
gfs2_holder_uninit(ghs + 1);
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
*/
static int gfs2_unlink_ok(struct gfs2_inode *dip, const struct qstr *name,
const struct gfs2_inode *ip)
{
int error;
if (IS_IMMUTABLE(&ip->i_inode) || IS_APPEND(&ip->i_inode))
return -EPERM;
if ((dip->i_inode.i_mode & S_ISVTX) &&
!uid_eq(dip->i_inode.i_uid, current_fsuid()) &&
!uid_eq(ip->i_inode.i_uid, current_fsuid()) && !capable(CAP_FOWNER))
return -EPERM;
if (IS_APPEND(&dip->i_inode))
return -EPERM;
error = gfs2_permission(&dip->i_inode, MAY_WRITE | MAY_EXEC);
if (error)
return error;
return gfs2_dir_check(&dip->i_inode, name, ip);
}
/**
* gfs2_unlink_inode - Removes an inode from its parent dir and unlinks it
* @dip: The parent directory
* @name: The name of the entry in the parent directory
* @inode: The inode to be removed
*
* Called with all the locks and in a transaction. This will only be
* called for a directory after it has been checked to ensure it is empty.
*
* Returns: 0 on success, or an error
*/
static int gfs2_unlink_inode(struct gfs2_inode *dip,
const struct dentry *dentry)
{
struct inode *inode = d_inode(dentry);
struct gfs2_inode *ip = GFS2_I(inode);
int error;
error = gfs2_dir_del(dip, dentry);
if (error)
return error;
ip->i_entries = 0;
inode->i_ctime = CURRENT_TIME;
if (S_ISDIR(inode->i_mode))
clear_nlink(inode);
else
drop_nlink(inode);
mark_inode_dirty(inode);
if (inode->i_nlink == 0)
gfs2_unlink_di(inode);
return 0;
}
/**
* gfs2_unlink - Unlink an inode (this does rmdir as well)
* @dir: The inode of the directory containing the inode to unlink
* @dentry: The file itself
*
* This routine uses the type of the inode as a flag to figure out
* whether this is an unlink or an rmdir.
*
* Returns: errno
*/
static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
{
struct gfs2_inode *dip = GFS2_I(dir);
struct gfs2_sbd *sdp = GFS2_SB(dir);
struct inode *inode = d_inode(dentry);
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder ghs[3];
struct gfs2_rgrpd *rgd;
int error;
error = gfs2_rindex_update(sdp);
if (error)
return error;
error = -EROFS;
gfs2_holder_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + 1);
rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
if (!rgd)
goto out_inodes;
gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
error = gfs2_glock_nq(ghs); /* parent */
if (error)
goto out_parent;
error = gfs2_glock_nq(ghs + 1); /* child */
if (error)
goto out_child;
error = -ENOENT;
if (inode->i_nlink == 0)
goto out_rgrp;
if (S_ISDIR(inode->i_mode)) {
error = -ENOTEMPTY;
if (ip->i_entries > 2 || inode->i_nlink > 2)
goto out_rgrp;
}
error = gfs2_glock_nq(ghs + 2); /* rgrp */
if (error)
goto out_rgrp;
error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
if (error)
goto out_gunlock;
error = gfs2_trans_begin(sdp, 2*RES_DINODE + 3*RES_LEAF + RES_RG_BIT, 0);
if (error)
goto out_end_trans;
error = gfs2_unlink_inode(dip, dentry);
out_end_trans:
gfs2_trans_end(sdp);
out_gunlock:
gfs2_glock_dq(ghs + 2);
out_rgrp:
gfs2_glock_dq(ghs + 1);
out_child:
gfs2_glock_dq(ghs);
out_parent:
gfs2_holder_uninit(ghs + 2);
out_inodes:
gfs2_holder_uninit(ghs + 1);
gfs2_holder_uninit(ghs);
return error;
}
/**
* gfs2_symlink - Create a symlink
* @dir: The directory to create the symlink in
* @dentry: The dentry to put the symlink in
* @symname: The thing which the link points to
*
* Returns: errno
*/
static int gfs2_symlink(struct inode *dir, struct dentry *dentry,
const char *symname)
{
struct gfs2_sbd *sdp = GFS2_SB(dir);
unsigned int size;
size = strlen(symname);
if (size > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode) - 1)
return -ENAMETOOLONG;
return gfs2_create_inode(dir, dentry, NULL, S_IFLNK | S_IRWXUGO, 0, symname, size, 0, NULL);
}
/**
* gfs2_mkdir - Make a directory
* @dir: The parent directory of the new one
* @dentry: The dentry of the new directory
* @mode: The mode of the new directory
*
* Returns: errno
*/
static int gfs2_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
struct gfs2_sbd *sdp = GFS2_SB(dir);
unsigned dsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode);
return gfs2_create_inode(dir, dentry, NULL, S_IFDIR | mode, 0, NULL, dsize, 0, NULL);
}
/**
* gfs2_mknod - Make a special file
* @dir: The directory in which the special file will reside
* @dentry: The dentry of the special file
* @mode: The mode of the special file
* @dev: The device specification of the special file
*
*/
static int gfs2_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
dev_t dev)
{
return gfs2_create_inode(dir, dentry, NULL, mode, dev, NULL, 0, 0, NULL);
}
/**
* gfs2_atomic_open - Atomically open a file
* @dir: The directory
* @dentry: The proposed new entry
* @file: The proposed new struct file
* @flags: open flags
* @mode: File mode
* @opened: Flag to say whether the file has been opened or not
*
* Returns: error code or 0 for success
*/
static int gfs2_atomic_open(struct inode *dir, struct dentry *dentry,
struct file *file, unsigned flags,
umode_t mode, int *opened)
{
struct dentry *d;
bool excl = !!(flags & O_EXCL);
if (!d_unhashed(dentry))
goto skip_lookup;
d = __gfs2_lookup(dir, dentry, file, opened);
if (IS_ERR(d))
return PTR_ERR(d);
if (d != NULL)
dentry = d;
if (d_really_is_positive(dentry)) {
if (!(*opened & FILE_OPENED))
return finish_no_open(file, d);
dput(d);
return 0;
}
BUG_ON(d != NULL);
skip_lookup:
if (!(flags & O_CREAT))
return -ENOENT;
return gfs2_create_inode(dir, dentry, file, S_IFREG | mode, 0, NULL, 0, excl, opened);
}
/*
* 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
*/
static 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;
int error = 0;
igrab(dir);
for (;;) {
if (dir == &this->i_inode) {
error = -EINVAL;
break;
}
if (dir == d_inode(sb->s_root)) {
error = 0;
break;
}
tmp = gfs2_lookupi(dir, &gfs2_qdotdot, 1);
if (!tmp) {
error = -ENOENT;
break;
}
if (IS_ERR(tmp)) {
error = PTR_ERR(tmp);
break;
}
iput(dir);
dir = tmp;
}
iput(dir);
return error;
}
/**
* update_moved_ino - Update an inode that's being moved
* @ip: The inode being moved
* @ndip: The parent directory of the new filename
* @dir_rename: True of ip is a directory
*
* Returns: errno
*/
static int update_moved_ino(struct gfs2_inode *ip, struct gfs2_inode *ndip,
int dir_rename)
{
int error;
struct buffer_head *dibh;
if (dir_rename)
return gfs2_dir_mvino(ip, &gfs2_qdotdot, ndip, DT_DIR);
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
return error;
ip->i_inode.i_ctime = CURRENT_TIME;
gfs2_trans_add_meta(ip->i_gl, dibh);
gfs2_dinode_out(ip, dibh->b_data);
brelse(dibh);
return 0;
}
/**
* gfs2_rename - Rename a file
* @odir: Parent directory of old file name
* @odentry: The old dentry of the file
* @ndir: Parent directory of new file name
* @ndentry: The new dentry of the file
*
* Returns: errno
*/
static int gfs2_rename(struct inode *odir, struct dentry *odentry,
struct inode *ndir, struct dentry *ndentry)
{
struct gfs2_inode *odip = GFS2_I(odir);
struct gfs2_inode *ndip = GFS2_I(ndir);
struct gfs2_inode *ip = GFS2_I(d_inode(odentry));
struct gfs2_inode *nip = NULL;
struct gfs2_sbd *sdp = GFS2_SB(odir);
struct gfs2_holder ghs[5], r_gh = { .gh_gl = NULL, };
struct gfs2_rgrpd *nrgd;
unsigned int num_gh;
int dir_rename = 0;
struct gfs2_diradd da = { .nr_blocks = 0, .save_loc = 0, };
unsigned int x;
int error;
if (d_really_is_positive(ndentry)) {
nip = GFS2_I(d_inode(ndentry));
if (ip == nip)
return 0;
}
error = gfs2_rindex_update(sdp);
if (error)
return error;
error = gfs2_rsqa_alloc(ndip);
if (error)
return error;
if (odip != ndip) {
error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
0, &r_gh);
if (error)
goto out;
if (S_ISDIR(ip->i_inode.i_mode)) {
dir_rename = 1;
/* don't move a directory into its subdir */
error = gfs2_ok_to_move(ip, ndip);
if (error)
goto out_gunlock_r;
}
}
num_gh = 1;
gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
if (odip != ndip) {
gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
num_gh++;
}
gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
num_gh++;
if (nip) {
gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
num_gh++;
/* grab the resource lock for unlink flag twiddling
* this is the case of the target file already existing
* so we unlink before doing the rename
*/
nrgd = gfs2_blk2rgrpd(sdp, nip->i_no_addr, 1);
if (nrgd)
gfs2_holder_init(nrgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh++);
}
for (x = 0; x < num_gh; x++) {
error = gfs2_glock_nq(ghs + x);
if (error)
goto out_gunlock;
}
error = -ENOENT;
if (ip->i_inode.i_nlink == 0)
goto out_gunlock;
/* Check out the old directory */
error = gfs2_unlink_ok(odip, &odentry->d_name, ip);
if (error)
goto out_gunlock;
/* Check out the new directory */
if (nip) {
error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
if (error)
goto out_gunlock;
if (nip->i_inode.i_nlink == 0) {
error = -EAGAIN;
goto out_gunlock;
}
if (S_ISDIR(nip->i_inode.i_mode)) {
if (nip->i_entries < 2) {
gfs2_consist_inode(nip);
error = -EIO;
goto out_gunlock;
}
if (nip->i_entries > 2) {
error = -ENOTEMPTY;
goto out_gunlock;
}
}
} else {
error = gfs2_permission(ndir, MAY_WRITE | MAY_EXEC);
if (error)
goto out_gunlock;
error = gfs2_dir_check(ndir, &ndentry->d_name, NULL);
switch (error) {
case -ENOENT:
error = 0;
break;
case 0:
error = -EEXIST;
default:
goto out_gunlock;
};
if (odip != ndip) {
if (!ndip->i_inode.i_nlink) {
error = -ENOENT;
goto out_gunlock;
}
if (ndip->i_entries == (u32)-1) {
error = -EFBIG;
goto out_gunlock;
}
if (S_ISDIR(ip->i_inode.i_mode) &&
ndip->i_inode.i_nlink == (u32)-1) {
error = -EMLINK;
goto out_gunlock;
}
}
}
/* Check out the dir to be renamed */
if (dir_rename) {
error = gfs2_permission(d_inode(odentry), MAY_WRITE);
if (error)
goto out_gunlock;
}
if (nip == NULL) {
error = gfs2_diradd_alloc_required(ndir, &ndentry->d_name, &da);
if (error)
goto out_gunlock;
}
if (da.nr_blocks) {
struct gfs2_alloc_parms ap = { .target = da.nr_blocks, };
error = gfs2_quota_lock_check(ndip, &ap);
if (error)
goto out_gunlock;
error = gfs2_inplace_reserve(ndip, &ap);
if (error)
goto out_gunlock_q;
error = gfs2_trans_begin(sdp, gfs2_trans_da_blks(ndip, &da, 4) +
4 * RES_LEAF + 4, 0);
if (error)
goto out_ipreserv;
} else {
error = gfs2_trans_begin(sdp, 4 * RES_DINODE +
5 * RES_LEAF + 4, 0);
if (error)
goto out_gunlock;
}
/* Remove the target file, if it exists */
if (nip)
error = gfs2_unlink_inode(ndip, ndentry);
error = update_moved_ino(ip, ndip, dir_rename);
if (error)
goto out_end_trans;
error = gfs2_dir_del(odip, odentry);
if (error)
goto out_end_trans;
error = gfs2_dir_add(ndir, &ndentry->d_name, ip, &da);
if (error)
goto out_end_trans;
out_end_trans:
gfs2_trans_end(sdp);
out_ipreserv:
if (da.nr_blocks)
gfs2_inplace_release(ndip);
out_gunlock_q:
if (da.nr_blocks)
gfs2_quota_unlock(ndip);
out_gunlock:
gfs2_dir_no_add(&da);
while (x--) {
gfs2_glock_dq(ghs + x);
gfs2_holder_uninit(ghs + x);
}
out_gunlock_r:
if (r_gh.gh_gl)
gfs2_glock_dq_uninit(&r_gh);
out:
return error;
}
/**
* gfs2_exchange - exchange two files
* @odir: Parent directory of old file name
* @odentry: The old dentry of the file
* @ndir: Parent directory of new file name
* @ndentry: The new dentry of the file
* @flags: The rename flags
*
* Returns: errno
*/
static int gfs2_exchange(struct inode *odir, struct dentry *odentry,
struct inode *ndir, struct dentry *ndentry,
unsigned int flags)
{
struct gfs2_inode *odip = GFS2_I(odir);
struct gfs2_inode *ndip = GFS2_I(ndir);
struct gfs2_inode *oip = GFS2_I(odentry->d_inode);
struct gfs2_inode *nip = GFS2_I(ndentry->d_inode);
struct gfs2_sbd *sdp = GFS2_SB(odir);
struct gfs2_holder ghs[5], r_gh = { .gh_gl = NULL, };
unsigned int num_gh;
unsigned int x;
umode_t old_mode = oip->i_inode.i_mode;
umode_t new_mode = nip->i_inode.i_mode;
int error;
error = gfs2_rindex_update(sdp);
if (error)
return error;
if (odip != ndip) {
error = gfs2_glock_nq_init(sdp->sd_rename_gl, LM_ST_EXCLUSIVE,
0, &r_gh);
if (error)
goto out;
if (S_ISDIR(old_mode)) {
/* don't move a directory into its subdir */
error = gfs2_ok_to_move(oip, ndip);
if (error)
goto out_gunlock_r;
}
if (S_ISDIR(new_mode)) {
/* don't move a directory into its subdir */
error = gfs2_ok_to_move(nip, odip);
if (error)
goto out_gunlock_r;
}
}
num_gh = 1;
gfs2_holder_init(odip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
if (odip != ndip) {
gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
num_gh++;
}
gfs2_holder_init(oip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
num_gh++;
gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, 0, ghs + num_gh);
num_gh++;
for (x = 0; x < num_gh; x++) {
error = gfs2_glock_nq(ghs + x);
if (error)
goto out_gunlock;
}
error = -ENOENT;
if (oip->i_inode.i_nlink == 0 || nip->i_inode.i_nlink == 0)
goto out_gunlock;
error = gfs2_unlink_ok(odip, &odentry->d_name, oip);
if (error)
goto out_gunlock;
error = gfs2_unlink_ok(ndip, &ndentry->d_name, nip);
if (error)
goto out_gunlock;
if (S_ISDIR(old_mode)) {
error = gfs2_permission(odentry->d_inode, MAY_WRITE);
if (error)
goto out_gunlock;
}
if (S_ISDIR(new_mode)) {
error = gfs2_permission(ndentry->d_inode, MAY_WRITE);
if (error)
goto out_gunlock;
}
error = gfs2_trans_begin(sdp, 4 * RES_DINODE + 4 * RES_LEAF, 0);
if (error)
goto out_gunlock;
error = update_moved_ino(oip, ndip, S_ISDIR(old_mode));
if (error)
goto out_end_trans;
error = update_moved_ino(nip, odip, S_ISDIR(new_mode));
if (error)
goto out_end_trans;
error = gfs2_dir_mvino(ndip, &ndentry->d_name, oip,
IF2DT(old_mode));
if (error)
goto out_end_trans;
error = gfs2_dir_mvino(odip, &odentry->d_name, nip,
IF2DT(new_mode));
if (error)
goto out_end_trans;
if (odip != ndip) {
if (S_ISDIR(new_mode) && !S_ISDIR(old_mode)) {
inc_nlink(&odip->i_inode);
drop_nlink(&ndip->i_inode);
} else if (S_ISDIR(old_mode) && !S_ISDIR(new_mode)) {
inc_nlink(&ndip->i_inode);
drop_nlink(&odip->i_inode);
}
}
mark_inode_dirty(&ndip->i_inode);
if (odip != ndip)
mark_inode_dirty(&odip->i_inode);
out_end_trans:
gfs2_trans_end(sdp);
out_gunlock:
while (x--) {
gfs2_glock_dq(ghs + x);
gfs2_holder_uninit(ghs + x);
}
out_gunlock_r:
if (r_gh.gh_gl)
gfs2_glock_dq_uninit(&r_gh);
out:
return error;
}
static int gfs2_rename2(struct inode *odir, struct dentry *odentry,
struct inode *ndir, struct dentry *ndentry,
unsigned int flags)
{
flags &= ~RENAME_NOREPLACE;
if (flags & ~RENAME_EXCHANGE)
return -EINVAL;
if (flags & RENAME_EXCHANGE)
return gfs2_exchange(odir, odentry, ndir, ndentry, flags);
return gfs2_rename(odir, odentry, ndir, ndentry);
}
/**
* gfs2_get_link - Follow a symbolic link
* @dentry: The dentry of the link
* @inode: The inode of the link
* @done: destructor for return value
*
* This can handle symlinks of any size.
*
* Returns: 0 on success or error code
*/
static const char *gfs2_get_link(struct dentry *dentry,
struct inode *inode,
struct delayed_call *done)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder i_gh;
struct buffer_head *dibh;
unsigned int size;
char *buf;
int error;
if (!dentry)
return ERR_PTR(-ECHILD);
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &i_gh);
error = gfs2_glock_nq(&i_gh);
if (error) {
gfs2_holder_uninit(&i_gh);
return ERR_PTR(error);
}
size = (unsigned int)i_size_read(&ip->i_inode);
if (size == 0) {
gfs2_consist_inode(ip);
buf = ERR_PTR(-EIO);
goto out;
}
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error) {
buf = ERR_PTR(error);
goto out;
}
buf = kzalloc(size + 1, GFP_NOFS);
if (!buf)
buf = ERR_PTR(-ENOMEM);
else
memcpy(buf, dibh->b_data + sizeof(struct gfs2_dinode), size);
brelse(dibh);
out:
gfs2_glock_dq_uninit(&i_gh);
if (!IS_ERR(buf))
set_delayed_call(done, kfree_link, buf);
return buf;
}
/**
* gfs2_permission -
* @inode: The inode
* @mask: The mask to be tested
* @flags: Indicates whether this is an RCU path walk or not
*
* This may be called from the VFS directly, or from within GFS2 with the
* inode locked, so we look to see if the glock is already locked and only
* lock the glock if its not already been done.
*
* Returns: errno
*/
int gfs2_permission(struct inode *inode, int mask)
{
struct gfs2_inode *ip;
struct gfs2_holder i_gh;
int error;
int unlock = 0;
ip = GFS2_I(inode);
if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
if (mask & MAY_NOT_BLOCK)
return -ECHILD;
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
if (error)
return error;
unlock = 1;
}
if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
error = -EACCES;
else
error = generic_permission(inode, mask);
if (unlock)
gfs2_glock_dq_uninit(&i_gh);
return error;
}
static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
{
setattr_copy(inode, attr);
mark_inode_dirty(inode);
return 0;
}
/**
* gfs2_setattr_simple -
* @ip:
* @attr:
*
* Returns: errno
*/
int gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
{
int error;
if (current->journal_info)
return __gfs2_setattr_simple(inode, attr);
error = gfs2_trans_begin(GFS2_SB(inode), RES_DINODE, 0);
if (error)
return error;
error = __gfs2_setattr_simple(inode, attr);
gfs2_trans_end(GFS2_SB(inode));
return error;
}
static int setattr_chown(struct inode *inode, struct iattr *attr)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
kuid_t ouid, nuid;
kgid_t ogid, ngid;
int error;
struct gfs2_alloc_parms ap;
ouid = inode->i_uid;
ogid = inode->i_gid;
nuid = attr->ia_uid;
ngid = attr->ia_gid;
if (!(attr->ia_valid & ATTR_UID) || uid_eq(ouid, nuid))
ouid = nuid = NO_UID_QUOTA_CHANGE;
if (!(attr->ia_valid & ATTR_GID) || gid_eq(ogid, ngid))
ogid = ngid = NO_GID_QUOTA_CHANGE;
error = gfs2_rsqa_alloc(ip);
if (error)
goto out;
error = gfs2_rindex_update(sdp);
if (error)
goto out;
error = gfs2_quota_lock(ip, nuid, ngid);
if (error)
goto out;
ap.target = gfs2_get_inode_blocks(&ip->i_inode);
if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
!gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
error = gfs2_quota_check(ip, nuid, ngid, &ap);
if (error)
goto out_gunlock_q;
}
error = gfs2_trans_begin(sdp, RES_DINODE + 2 * RES_QUOTA, 0);
if (error)
goto out_gunlock_q;
error = gfs2_setattr_simple(inode, attr);
if (error)
goto out_end_trans;
if (!uid_eq(ouid, NO_UID_QUOTA_CHANGE) ||
!gid_eq(ogid, NO_GID_QUOTA_CHANGE)) {
gfs2_quota_change(ip, -(s64)ap.target, ouid, ogid);
gfs2_quota_change(ip, ap.target, nuid, ngid);
}
out_end_trans:
gfs2_trans_end(sdp);
out_gunlock_q:
gfs2_quota_unlock(ip);
out:
return error;
}
/**
* gfs2_setattr - Change attributes on an inode
* @dentry: The dentry which is changing
* @attr: The structure describing the change
*
* The VFS layer wants to change one or more of an inodes attributes. Write
* that change out to disk.
*
* Returns: errno
*/
static int gfs2_setattr(struct dentry *dentry, struct iattr *attr)
{
struct inode *inode = d_inode(dentry);
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder i_gh;
int error;
error = gfs2_rsqa_alloc(ip);
if (error)
return error;
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
if (error)
return error;
error = -EPERM;
if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
goto out;
error = inode_change_ok(inode, attr);
if (error)
goto out;
if (attr->ia_valid & ATTR_SIZE)
error = gfs2_setattr_size(inode, attr->ia_size);
else if (attr->ia_valid & (ATTR_UID | ATTR_GID))
error = setattr_chown(inode, attr);
else {
error = gfs2_setattr_simple(inode, attr);
if (!error && attr->ia_valid & ATTR_MODE)
error = posix_acl_chmod(inode, inode->i_mode);
}
out:
if (!error)
mark_inode_dirty(inode);
gfs2_glock_dq_uninit(&i_gh);
return error;
}
/**
* gfs2_getattr - Read out an inode's attributes
* @mnt: The vfsmount the inode is being accessed from
* @dentry: The dentry to stat
* @stat: The inode's stats
*
* This may be called from the VFS directly, or from within GFS2 with the
* inode locked, so we look to see if the glock is already locked and only
* lock the glock if its not already been done. Note that its the NFS
* readdirplus operation which causes this to be called (from filldir)
* with the glock already held.
*
* Returns: errno
*/
static int gfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
struct kstat *stat)
{
struct inode *inode = d_inode(dentry);
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder gh;
int error;
int unlock = 0;
if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) {
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
if (error)
return error;
unlock = 1;
}
generic_fillattr(inode, stat);
if (unlock)
gfs2_glock_dq_uninit(&gh);
return 0;
}
static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
u64 start, u64 len)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder gh;
int ret;
ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
if (ret)
return ret;
inode_lock(inode);
ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
if (ret)
goto out;
if (gfs2_is_stuffed(ip)) {
u64 phys = ip->i_no_addr << inode->i_blkbits;
u64 size = i_size_read(inode);
u32 flags = FIEMAP_EXTENT_LAST|FIEMAP_EXTENT_NOT_ALIGNED|
FIEMAP_EXTENT_DATA_INLINE;
phys += sizeof(struct gfs2_dinode);
phys += start;
if (start + len > size)
len = size - start;
if (start < size)
ret = fiemap_fill_next_extent(fieinfo, start, phys,
len, flags);
if (ret == 1)
ret = 0;
} else {
ret = __generic_block_fiemap(inode, fieinfo, start, len,
gfs2_block_map);
}
gfs2_glock_dq_uninit(&gh);
out:
inode_unlock(inode);
return ret;
}
const struct inode_operations gfs2_file_iops = {
.permission = gfs2_permission,
.setattr = gfs2_setattr,
.getattr = gfs2_getattr,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.listxattr = gfs2_listxattr,
.removexattr = generic_removexattr,
.fiemap = gfs2_fiemap,
.get_acl = gfs2_get_acl,
.set_acl = gfs2_set_acl,
};
const struct inode_operations gfs2_dir_iops = {
.create = gfs2_create,
.lookup = gfs2_lookup,
.link = gfs2_link,
.unlink = gfs2_unlink,
.symlink = gfs2_symlink,
.mkdir = gfs2_mkdir,
.rmdir = gfs2_unlink,
.mknod = gfs2_mknod,
.rename2 = gfs2_rename2,
.permission = gfs2_permission,
.setattr = gfs2_setattr,
.getattr = gfs2_getattr,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.listxattr = gfs2_listxattr,
.removexattr = generic_removexattr,
.fiemap = gfs2_fiemap,
.get_acl = gfs2_get_acl,
.set_acl = gfs2_set_acl,
.atomic_open = gfs2_atomic_open,
};
const struct inode_operations gfs2_symlink_iops = {
.readlink = generic_readlink,
.get_link = gfs2_get_link,
.permission = gfs2_permission,
.setattr = gfs2_setattr,
.getattr = gfs2_getattr,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.listxattr = gfs2_listxattr,
.removexattr = generic_removexattr,
.fiemap = gfs2_fiemap,
};
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