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linux/fs/gfs2/inode.c
Christian Brauner cac2f8b8d8
fs: rename current get acl method 
The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

The current inode operation for getting posix acls takes an inode
argument but various filesystems (e.g., 9p, cifs, overlayfs) need access
to the dentry. In contrast to the ->set_acl() inode operation we cannot
simply extend ->get_acl() to take a dentry argument. The ->get_acl()
inode operation is called from:

acl_permission_check()
-> check_acl()
   -> get_acl()

which is part of generic_permission() which in turn is part of
inode_permission(). Both generic_permission() and inode_permission() are
called in the ->permission() handler of various filesystems (e.g.,
overlayfs). So simply passing a dentry argument to ->get_acl() would
amount to also having to pass a dentry argument to ->permission(). We
should avoid this unnecessary change.

So instead of extending the existing inode operation rename it from
->get_acl() to ->get_inode_acl() and add a ->get_acl() method later that
passes a dentry argument and which filesystems that need access to the
dentry can implement instead of ->get_inode_acl(). Filesystems like cifs
which allow setting and getting posix acls but not using them for
permission checking during lookup can simply not implement
->get_inode_acl().

This is intended to be a non-functional change.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Suggested-by/Inspired-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-20 10:13:27 +02:00

2191 lines
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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2011 Red Hat, Inc. All rights reserved.
*/
#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/cred.h>
#include <linux/xattr.h>
#include <linux/posix_acl.h>
#include <linux/gfs2_ondisk.h>
#include <linux/crc32.h>
#include <linux/iomap.h>
#include <linux/security.h>
#include <linux/fiemap.h>
#include <linux/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"
static const struct inode_operations gfs2_file_iops;
static const struct inode_operations gfs2_dir_iops;
static const struct inode_operations gfs2_symlink_iops;
/**
* 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);
}
}
static int iget_test(struct inode *inode, void *opaque)
{
u64 no_addr = *(u64 *)opaque;
return GFS2_I(inode)->i_no_addr == no_addr;
}
static int iget_set(struct inode *inode, void *opaque)
{
u64 no_addr = *(u64 *)opaque;
GFS2_I(inode)->i_no_addr = no_addr;
inode->i_ino = no_addr;
return 0;
}
/**
* 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 to 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.
*
* When @no_formal_ino is non-zero, this function will return ERR_PTR(-ESTALE)
* if it detects that @no_formal_ino doesn't match the actual inode generation
* number. However, it doesn't always know unless @type is DT_UNKNOWN.
*
* 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_holder i_gh;
int error;
gfs2_holder_mark_uninitialized(&i_gh);
inode = iget5_locked(sb, no_addr, iget_test, iget_set, &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);
struct gfs2_glock *io_gl;
int extra_flags = 0;
error = gfs2_glock_get(sdp, no_addr, &gfs2_inode_glops, CREATE,
&ip->i_gl);
if (unlikely(error))
goto fail;
error = gfs2_glock_get(sdp, no_addr, &gfs2_iopen_glops, CREATE,
&io_gl);
if (unlikely(error))
goto fail;
if (blktype == GFS2_BLKST_UNLINKED)
extra_flags |= LM_FLAG_TRY;
else
gfs2_cancel_delete_work(io_gl);
error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED,
GL_EXACT | GL_NOPID | extra_flags,
&ip->i_iopen_gh);
gfs2_glock_put(io_gl);
if (unlikely(error))
goto fail;
if (type == DT_UNKNOWN || blktype != GFS2_BLKST_FREE) {
/*
* The GL_SKIP flag indicates to skip reading the inode
* block. We read the inode when instantiating it
* 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;
error = -ESTALE;
if (no_formal_ino &&
gfs2_inode_already_deleted(ip->i_gl, no_formal_ino))
goto fail;
if (blktype != GFS2_BLKST_FREE) {
error = gfs2_check_blk_type(sdp, no_addr,
blktype);
if (error)
goto fail;
}
}
set_bit(GLF_INSTANTIATE_NEEDED, &ip->i_gl->gl_flags);
/* Lowest possible timestamp; will be overwritten in gfs2_dinode_in. */
inode->i_atime.tv_sec = 1LL << (8 * sizeof(inode->i_atime.tv_sec) - 1);
inode->i_atime.tv_nsec = 0;
glock_set_object(ip->i_gl, ip);
if (type == DT_UNKNOWN) {
/* Inode glock must be locked already */
error = gfs2_instantiate(&i_gh);
if (error) {
glock_clear_object(ip->i_gl, ip);
goto fail;
}
} else {
ip->i_no_formal_ino = no_formal_ino;
inode->i_mode = DT2IF(type);
}
if (gfs2_holder_initialized(&i_gh))
gfs2_glock_dq_uninit(&i_gh);
glock_set_object(ip->i_iopen_gh.gh_gl, ip);
gfs2_set_iop(inode);
unlock_new_inode(inode);
}
if (no_formal_ino && ip->i_no_formal_ino &&
no_formal_ino != ip->i_no_formal_ino) {
iput(inode);
return ERR_PTR(-ESTALE);
}
return inode;
fail:
if (error == GLR_TRYFAILED)
error = -EAGAIN;
if (gfs2_holder_initialized(&ip->i_iopen_gh))
gfs2_glock_dq_uninit(&ip->i_iopen_gh);
if (gfs2_holder_initialized(&i_gh))
gfs2_glock_dq_uninit(&i_gh);
iget_failed(inode);
return ERR_PTR(error);
}
/**
* gfs2_lookup_by_inum - look up an inode by inode number
* @sdp: The super block
* @no_addr: The inode number
* @no_formal_ino: The inode generation number (0 for any)
* @blktype: Requested block type (see gfs2_inode_lookup)
*/
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, no_formal_ino,
blktype);
if (IS_ERR(inode))
return inode;
if (no_formal_ino) {
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
* @dir: The inode of the directory containing the inode to look-up
* @name: The name of the inode to look for
* @is_root: If 1, ignore the caller's permissions
*
* 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;
gfs2_holder_mark_uninitialized(&d_gh);
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);
}
if (!is_root) {
error = gfs2_permission(&init_user_ns, dir, MAY_EXEC);
if (error)
goto out;
}
inode = gfs2_dir_search(dir, name, false);
if (IS_ERR(inode))
error = PTR_ERR(inode);
out:
if (gfs2_holder_initialized(&d_gh))
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(&init_user_ns, &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)
*
*/
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(imajor(&ip->i_inode));
di->di_minor = cpu_to_be32(iminor(&ip->i_inode));
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_blks - 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)
* @excl: Force fail if inode exists
*
* 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)
{
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;
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_qa_get(dip);
if (error)
return error;
error = gfs2_rindex_update(sdp);
if (error)
goto fail;
error = gfs2_glock_nq_init(dip->i_gl, LM_ST_EXCLUSIVE, 0, ghs);
if (error)
goto fail;
gfs2_holder_mark_uninitialized(ghs + 1);
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);
else
error = finish_no_open(file, NULL);
}
gfs2_glock_dq_uninit(ghs);
goto fail;
} 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_qa_get(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(inode);
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;
ip->i_no_addr = 0; /* Temporarily zero until real addr is assigned */
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;
error = gfs2_glock_get(sdp, ip->i_no_addr, &gfs2_iopen_glops, CREATE, &io_gl);
if (error)
goto fail_free_inode;
gfs2_cancel_delete_work(io_gl);
error = insert_inode_locked4(inode, ip->i_no_addr, iget_test, &ip->i_no_addr);
BUG_ON(error);
error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT | GL_NOPID,
&ip->i_iopen_gh);
if (error)
goto fail_gunlock2;
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, ghs + 1);
if (error)
goto fail_gunlock3;
error = gfs2_trans_begin(sdp, blocks, 0);
if (error)
goto fail_gunlock3;
if (blocks > 1) {
ip->i_eattr = ip->i_no_addr + 1;
gfs2_init_xattr(ip);
}
init_dinode(dip, ip, symname);
gfs2_trans_end(sdp);
glock_set_object(ip->i_gl, ip);
glock_set_object(io_gl, ip);
gfs2_set_iop(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);
if (error)
goto fail_gunlock4;
posix_acl_release(default_acl);
default_acl = NULL;
}
if (acl) {
error = __gfs2_set_acl(inode, acl, ACL_TYPE_ACCESS);
if (error)
goto fail_gunlock4;
posix_acl_release(acl);
acl = NULL;
}
error = security_inode_init_security(&ip->i_inode, &dip->i_inode, name,
&gfs2_initxattrs, NULL);
if (error)
goto fail_gunlock4;
error = link_dinode(dip, name, ip, &da);
if (error)
goto fail_gunlock4;
mark_inode_dirty(inode);
d_instantiate(dentry, inode);
/* After instantiate, errors should result in evict which will destroy
* both inode and iopen glocks properly. */
if (file) {
file->f_mode |= FMODE_CREATED;
error = finish_open(file, dentry, gfs2_open_common);
}
gfs2_glock_dq_uninit(ghs);
gfs2_qa_put(ip);
gfs2_glock_dq_uninit(ghs + 1);
gfs2_glock_put(io_gl);
gfs2_qa_put(dip);
unlock_new_inode(inode);
return error;
fail_gunlock4:
glock_clear_object(ip->i_gl, ip);
glock_clear_object(io_gl, ip);
fail_gunlock3:
gfs2_glock_dq_uninit(&ip->i_iopen_gh);
fail_gunlock2:
gfs2_glock_put(io_gl);
fail_free_inode:
if (ip->i_gl) {
if (free_vfs_inode) /* else evict will do the put for us */
gfs2_glock_put(ip->i_gl);
}
gfs2_rs_deltree(&ip->i_res);
gfs2_qa_put(ip);
fail_free_acls:
posix_acl_release(default_acl);
posix_acl_release(acl);
fail_gunlock:
gfs2_dir_no_add(&da);
gfs2_glock_dq_uninit(ghs);
if (!IS_ERR_OR_NULL(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);
if (inode->i_state & I_NEW)
iget_failed(inode);
else
iput(inode);
}
if (gfs2_holder_initialized(ghs + 1))
gfs2_glock_dq_uninit(ghs + 1);
fail:
gfs2_qa_put(dip);
return error;
}
/**
* gfs2_create - Create a file
* @mnt_userns: User namespace of the mount the inode was found from
* @dir: The directory in which to create the file
* @dentry: The dentry of the new file
* @mode: The mode of the new file
* @excl: Force fail if inode exists
*
* Returns: errno
*/
static int gfs2_create(struct user_namespace *mnt_userns, 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);
}
/**
* __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
*
*
* Returns: errno
*/
static struct dentry *__gfs2_lookup(struct inode *dir, struct dentry *dentry,
struct file *file)
{
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);
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);
}
/**
* 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_qa_get(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(&init_user_ns, 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;
goto out_gunlock;
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(&ip->i_inode);
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_qa_put(dip);
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(&init_user_ns, &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
* @dentry: The dentry to unlink
*
* 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(inode);
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, LM_FLAG_NODE_SCOPE, 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_gunlock;
error = gfs2_unlink_inode(dip, dentry);
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
* @mnt_userns: User namespace of the mount the inode was found from
* @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 user_namespace *mnt_userns, struct inode *dir,
struct dentry *dentry, const char *symname)
{
unsigned int size;
size = strlen(symname);
if (size >= gfs2_max_stuffed_size(GFS2_I(dir)))
return -ENAMETOOLONG;
return gfs2_create_inode(dir, dentry, NULL, S_IFLNK | S_IRWXUGO, 0, symname, size, 0);
}
/**
* gfs2_mkdir - Make a directory
* @mnt_userns: User namespace of the mount the inode was found from
* @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 user_namespace *mnt_userns, struct inode *dir,
struct dentry *dentry, umode_t mode)
{
unsigned dsize = gfs2_max_stuffed_size(GFS2_I(dir));
return gfs2_create_inode(dir, dentry, NULL, S_IFDIR | mode, 0, NULL, dsize, 0);
}
/**
* gfs2_mknod - Make a special file
* @mnt_userns: User namespace of the mount the inode was found from
* @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 user_namespace *mnt_userns, struct inode *dir,
struct dentry *dentry, umode_t mode, dev_t dev)
{
return gfs2_create_inode(dir, dentry, NULL, mode, dev, NULL, 0, 0);
}
/**
* 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
*
* 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)
{
struct dentry *d;
bool excl = !!(flags & O_EXCL);
if (!d_in_lookup(dentry))
goto skip_lookup;
d = __gfs2_lookup(dir, dentry, file);
if (IS_ERR(d))
return PTR_ERR(d);
if (d != NULL)
dentry = d;
if (d_really_is_positive(dentry)) {
if (!(file->f_mode & FMODE_OPENED))
return finish_no_open(file, d);
dput(d);
return excl && (flags & O_CREAT) ? -EEXIST : 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);
}
/*
* 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)
{
if (dir_rename)
return gfs2_dir_mvino(ip, &gfs2_qdotdot, ndip, DT_DIR);
ip->i_inode.i_ctime = current_time(&ip->i_inode);
mark_inode_dirty_sync(&ip->i_inode);
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[4], r_gh, rd_gh;
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;
gfs2_holder_mark_uninitialized(&r_gh);
gfs2_holder_mark_uninitialized(&rd_gh);
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_qa_get(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, GL_ASYNC, ghs);
if (odip != ndip) {
gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE,GL_ASYNC,
ghs + num_gh);
num_gh++;
}
gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
num_gh++;
if (nip) {
gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC,
ghs + num_gh);
num_gh++;
}
for (x = 0; x < num_gh; x++) {
error = gfs2_glock_nq(ghs + x);
if (error)
goto out_gunlock;
}
error = gfs2_glock_async_wait(num_gh, ghs);
if (error)
goto out_gunlock;
if (nip) {
/* Grab the resource group glock for unlink flag twiddling.
* This is the case where the target dinode already exists
* so we unlink before doing the rename.
*/
nrgd = gfs2_blk2rgrpd(sdp, nip->i_no_addr, 1);
if (!nrgd) {
error = -ENOENT;
goto out_gunlock;
}
error = gfs2_glock_nq_init(nrgd->rd_gl, LM_ST_EXCLUSIVE,
LM_FLAG_NODE_SCOPE, &rd_gh);
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(&init_user_ns, 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;
goto out_gunlock;
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(&init_user_ns, 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);
if (gfs2_holder_initialized(&rd_gh))
gfs2_glock_dq_uninit(&rd_gh);
while (x--) {
if (gfs2_holder_queued(ghs + x))
gfs2_glock_dq(ghs + x);
gfs2_holder_uninit(ghs + x);
}
out_gunlock_r:
if (gfs2_holder_initialized(&r_gh))
gfs2_glock_dq_uninit(&r_gh);
out:
gfs2_qa_put(ndip);
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[4], r_gh;
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;
gfs2_holder_mark_uninitialized(&r_gh);
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, GL_ASYNC, ghs);
if (odip != ndip) {
gfs2_holder_init(ndip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC,
ghs + num_gh);
num_gh++;
}
gfs2_holder_init(oip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
num_gh++;
gfs2_holder_init(nip->i_gl, LM_ST_EXCLUSIVE, GL_ASYNC, ghs + num_gh);
num_gh++;
for (x = 0; x < num_gh; x++) {
error = gfs2_glock_nq(ghs + x);
if (error)
goto out_gunlock;
}
error = gfs2_glock_async_wait(num_gh, ghs);
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(&init_user_ns, odentry->d_inode,
MAY_WRITE);
if (error)
goto out_gunlock;
}
if (S_ISDIR(new_mode)) {
error = gfs2_permission(&init_user_ns, 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--) {
if (gfs2_holder_queued(ghs + x))
gfs2_glock_dq(ghs + x);
gfs2_holder_uninit(ghs + x);
}
out_gunlock_r:
if (gfs2_holder_initialized(&r_gh))
gfs2_glock_dq_uninit(&r_gh);
out:
return error;
}
static int gfs2_rename2(struct user_namespace *mnt_userns, 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
* @mnt_userns: User namespace of the mount the inode was found from
* @inode: The inode
* @mask: The mask to be tested
*
* 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 user_namespace *mnt_userns, struct inode *inode,
int mask)
{
struct gfs2_inode *ip;
struct gfs2_holder i_gh;
int error;
gfs2_holder_mark_uninitialized(&i_gh);
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;
}
if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode))
error = -EPERM;
else
error = generic_permission(&init_user_ns, inode, mask);
if (gfs2_holder_initialized(&i_gh))
gfs2_glock_dq_uninit(&i_gh);
return error;
}
static int __gfs2_setattr_simple(struct inode *inode, struct iattr *attr)
{
setattr_copy(&init_user_ns, inode, attr);
mark_inode_dirty(inode);
return 0;
}
static 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_qa_get(ip);
if (error)
return error;
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:
gfs2_qa_put(ip);
return error;
}
/**
* gfs2_setattr - Change attributes on an inode
* @mnt_userns: User namespace of the mount the inode was found from
* @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 user_namespace *mnt_userns,
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_qa_get(ip);
if (error)
return error;
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
if (error)
goto out;
error = may_setattr(&init_user_ns, inode, attr->ia_valid);
if (error)
goto error;
error = setattr_prepare(&init_user_ns, dentry, attr);
if (error)
goto error;
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(&init_user_ns, dentry,
inode->i_mode);
}
error:
if (!error)
mark_inode_dirty(inode);
gfs2_glock_dq_uninit(&i_gh);
out:
gfs2_qa_put(ip);
return error;
}
/**
* gfs2_getattr - Read out an inode's attributes
* @mnt_userns: user namespace of the mount the inode was found from
* @path: Object to query
* @stat: The inode's stats
* @request_mask: Mask of STATX_xxx flags indicating the caller's interests
* @flags: AT_STATX_xxx setting
*
* 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 user_namespace *mnt_userns,
const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int flags)
{
struct inode *inode = d_inode(path->dentry);
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder gh;
u32 gfsflags;
int error;
gfs2_holder_mark_uninitialized(&gh);
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;
}
gfsflags = ip->i_diskflags;
if (gfsflags & GFS2_DIF_APPENDONLY)
stat->attributes |= STATX_ATTR_APPEND;
if (gfsflags & GFS2_DIF_IMMUTABLE)
stat->attributes |= STATX_ATTR_IMMUTABLE;
stat->attributes_mask |= (STATX_ATTR_APPEND |
STATX_ATTR_COMPRESSED |
STATX_ATTR_ENCRYPTED |
STATX_ATTR_IMMUTABLE |
STATX_ATTR_NODUMP);
generic_fillattr(&init_user_ns, inode, stat);
if (gfs2_holder_initialized(&gh))
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;
inode_lock_shared(inode);
ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
if (ret)
goto out;
ret = iomap_fiemap(inode, fieinfo, start, len, &gfs2_iomap_ops);
gfs2_glock_dq_uninit(&gh);
out:
inode_unlock_shared(inode);
return ret;
}
loff_t gfs2_seek_data(struct file *file, loff_t offset)
{
struct inode *inode = file->f_mapping->host;
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder gh;
loff_t ret;
inode_lock_shared(inode);
ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
if (!ret)
ret = iomap_seek_data(inode, offset, &gfs2_iomap_ops);
gfs2_glock_dq_uninit(&gh);
inode_unlock_shared(inode);
if (ret < 0)
return ret;
return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);
}
loff_t gfs2_seek_hole(struct file *file, loff_t offset)
{
struct inode *inode = file->f_mapping->host;
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder gh;
loff_t ret;
inode_lock_shared(inode);
ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
if (!ret)
ret = iomap_seek_hole(inode, offset, &gfs2_iomap_ops);
gfs2_glock_dq_uninit(&gh);
inode_unlock_shared(inode);
if (ret < 0)
return ret;
return vfs_setpos(file, ret, inode->i_sb->s_maxbytes);
}
static int gfs2_update_time(struct inode *inode, struct timespec64 *time,
int flags)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_glock *gl = ip->i_gl;
struct gfs2_holder *gh;
int error;
gh = gfs2_glock_is_locked_by_me(gl);
if (gh && !gfs2_glock_is_held_excl(gl)) {
gfs2_glock_dq(gh);
gfs2_holder_reinit(LM_ST_EXCLUSIVE, 0, gh);
error = gfs2_glock_nq(gh);
if (error)
return error;
}
return generic_update_time(inode, time, flags);
}
static const struct inode_operations gfs2_file_iops = {
.permission = gfs2_permission,
.setattr = gfs2_setattr,
.getattr = gfs2_getattr,
.listxattr = gfs2_listxattr,
.fiemap = gfs2_fiemap,
.get_inode_acl = gfs2_get_acl,
.set_acl = gfs2_set_acl,
.update_time = gfs2_update_time,
.fileattr_get = gfs2_fileattr_get,
.fileattr_set = gfs2_fileattr_set,
};
static 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,
.rename = gfs2_rename2,
.permission = gfs2_permission,
.setattr = gfs2_setattr,
.getattr = gfs2_getattr,
.listxattr = gfs2_listxattr,
.fiemap = gfs2_fiemap,
.get_inode_acl = gfs2_get_acl,
.set_acl = gfs2_set_acl,
.update_time = gfs2_update_time,
.atomic_open = gfs2_atomic_open,
.fileattr_get = gfs2_fileattr_get,
.fileattr_set = gfs2_fileattr_set,
};
static const struct inode_operations gfs2_symlink_iops = {
.get_link = gfs2_get_link,
.permission = gfs2_permission,
.setattr = gfs2_setattr,
.getattr = gfs2_getattr,
.listxattr = gfs2_listxattr,
.fiemap = gfs2_fiemap,
};
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