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namei.c
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namei.c
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/*
* Copyright (C) International Business Machines Corp., 2000-2004
* Portions Copyright (C) Christoph Hellwig, 2001-2002
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
#include <linux/ctype.h>
#include <linux/quotaops.h>
#include <linux/exportfs.h>
#include "jfs_incore.h"
#include "jfs_superblock.h"
#include "jfs_inode.h"
#include "jfs_dinode.h"
#include "jfs_dmap.h"
#include "jfs_unicode.h"
#include "jfs_metapage.h"
#include "jfs_xattr.h"
#include "jfs_acl.h"
#include "jfs_debug.h"
/*
* forward references
*/
const struct dentry_operations jfs_ci_dentry_operations;
static s64 commitZeroLink(tid_t, struct inode *);
/*
* NAME: free_ea_wmap(inode)
*
* FUNCTION: free uncommitted extended attributes from working map
*
*/
static inline void free_ea_wmap(struct inode *inode)
{
dxd_t *ea = &JFS_IP(inode)->ea;
if (ea->flag & DXD_EXTENT) {
/* free EA pages from cache */
invalidate_dxd_metapages(inode, *ea);
dbFree(inode, addressDXD(ea), lengthDXD(ea));
}
ea->flag = 0;
}
/*
* NAME: jfs_create(dip, dentry, mode)
*
* FUNCTION: create a regular file in the parent directory <dip>
* with name = <from dentry> and mode = <mode>
*
* PARAMETER: dip - parent directory vnode
* dentry - dentry of new file
* mode - create mode (rwxrwxrwx).
* nd- nd struct
*
* RETURN: Errors from subroutines
*
*/
static int jfs_create(struct inode *dip, struct dentry *dentry, int mode,
struct nameidata *nd)
{
int rc = 0;
tid_t tid; /* transaction id */
struct inode *ip = NULL; /* child directory inode */
ino_t ino;
struct component_name dname; /* child directory name */
struct btstack btstack;
struct inode *iplist[2];
struct tblock *tblk;
jfs_info("jfs_create: dip:0x%p name:%s", dip, dentry->d_name.name);
/*
* search parent directory for entry/freespace
* (dtSearch() returns parent directory page pinned)
*/
if ((rc = get_UCSname(&dname, dentry)))
goto out1;
/*
* Either iAlloc() or txBegin() may block. Deadlock can occur if we
* block there while holding dtree page, so we allocate the inode &
* begin the transaction before we search the directory.
*/
ip = ialloc(dip, mode);
if (IS_ERR(ip)) {
rc = PTR_ERR(ip);
goto out2;
}
tid = txBegin(dip->i_sb, 0);
mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
rc = jfs_init_acl(tid, ip, dip);
if (rc)
goto out3;
rc = jfs_init_security(tid, ip, dip);
if (rc) {
txAbort(tid, 0);
goto out3;
}
if ((rc = dtSearch(dip, &dname, &ino, &btstack, JFS_CREATE))) {
jfs_err("jfs_create: dtSearch returned %d", rc);
txAbort(tid, 0);
goto out3;
}
tblk = tid_to_tblock(tid);
tblk->xflag |= COMMIT_CREATE;
tblk->ino = ip->i_ino;
tblk->u.ixpxd = JFS_IP(ip)->ixpxd;
iplist[0] = dip;
iplist[1] = ip;
/*
* initialize the child XAD tree root in-line in inode
*/
xtInitRoot(tid, ip);
/*
* create entry in parent directory for child directory
* (dtInsert() releases parent directory page)
*/
ino = ip->i_ino;
if ((rc = dtInsert(tid, dip, &dname, &ino, &btstack))) {
if (rc == -EIO) {
jfs_err("jfs_create: dtInsert returned -EIO");
txAbort(tid, 1); /* Marks Filesystem dirty */
} else
txAbort(tid, 0); /* Filesystem full */
goto out3;
}
ip->i_op = &jfs_file_inode_operations;
ip->i_fop = &jfs_file_operations;
ip->i_mapping->a_ops = &jfs_aops;
mark_inode_dirty(ip);
dip->i_ctime = dip->i_mtime = CURRENT_TIME;
mark_inode_dirty(dip);
rc = txCommit(tid, 2, &iplist[0], 0);
out3:
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
mutex_unlock(&JFS_IP(dip)->commit_mutex);
if (rc) {
free_ea_wmap(ip);
ip->i_nlink = 0;
unlock_new_inode(ip);
iput(ip);
} else {
d_instantiate(dentry, ip);
unlock_new_inode(ip);
}
out2:
free_UCSname(&dname);
out1:
jfs_info("jfs_create: rc:%d", rc);
return rc;
}
/*
* NAME: jfs_mkdir(dip, dentry, mode)
*
* FUNCTION: create a child directory in the parent directory <dip>
* with name = <from dentry> and mode = <mode>
*
* PARAMETER: dip - parent directory vnode
* dentry - dentry of child directory
* mode - create mode (rwxrwxrwx).
*
* RETURN: Errors from subroutines
*
* note:
* EACCESS: user needs search+write permission on the parent directory
*/
static int jfs_mkdir(struct inode *dip, struct dentry *dentry, int mode)
{
int rc = 0;
tid_t tid; /* transaction id */
struct inode *ip = NULL; /* child directory inode */
ino_t ino;
struct component_name dname; /* child directory name */
struct btstack btstack;
struct inode *iplist[2];
struct tblock *tblk;
jfs_info("jfs_mkdir: dip:0x%p name:%s", dip, dentry->d_name.name);
/* link count overflow on parent directory ? */
if (dip->i_nlink == JFS_LINK_MAX) {
rc = -EMLINK;
goto out1;
}
/*
* search parent directory for entry/freespace
* (dtSearch() returns parent directory page pinned)
*/
if ((rc = get_UCSname(&dname, dentry)))
goto out1;
/*
* Either iAlloc() or txBegin() may block. Deadlock can occur if we
* block there while holding dtree page, so we allocate the inode &
* begin the transaction before we search the directory.
*/
ip = ialloc(dip, S_IFDIR | mode);
if (IS_ERR(ip)) {
rc = PTR_ERR(ip);
goto out2;
}
tid = txBegin(dip->i_sb, 0);
mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
rc = jfs_init_acl(tid, ip, dip);
if (rc)
goto out3;
rc = jfs_init_security(tid, ip, dip);
if (rc) {
txAbort(tid, 0);
goto out3;
}
if ((rc = dtSearch(dip, &dname, &ino, &btstack, JFS_CREATE))) {
jfs_err("jfs_mkdir: dtSearch returned %d", rc);
txAbort(tid, 0);
goto out3;
}
tblk = tid_to_tblock(tid);
tblk->xflag |= COMMIT_CREATE;
tblk->ino = ip->i_ino;
tblk->u.ixpxd = JFS_IP(ip)->ixpxd;
iplist[0] = dip;
iplist[1] = ip;
/*
* initialize the child directory in-line in inode
*/
dtInitRoot(tid, ip, dip->i_ino);
/*
* create entry in parent directory for child directory
* (dtInsert() releases parent directory page)
*/
ino = ip->i_ino;
if ((rc = dtInsert(tid, dip, &dname, &ino, &btstack))) {
if (rc == -EIO) {
jfs_err("jfs_mkdir: dtInsert returned -EIO");
txAbort(tid, 1); /* Marks Filesystem dirty */
} else
txAbort(tid, 0); /* Filesystem full */
goto out3;
}
ip->i_nlink = 2; /* for '.' */
ip->i_op = &jfs_dir_inode_operations;
ip->i_fop = &jfs_dir_operations;
mark_inode_dirty(ip);
/* update parent directory inode */
inc_nlink(dip); /* for '..' from child directory */
dip->i_ctime = dip->i_mtime = CURRENT_TIME;
mark_inode_dirty(dip);
rc = txCommit(tid, 2, &iplist[0], 0);
out3:
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
mutex_unlock(&JFS_IP(dip)->commit_mutex);
if (rc) {
free_ea_wmap(ip);
ip->i_nlink = 0;
unlock_new_inode(ip);
iput(ip);
} else {
d_instantiate(dentry, ip);
unlock_new_inode(ip);
}
out2:
free_UCSname(&dname);
out1:
jfs_info("jfs_mkdir: rc:%d", rc);
return rc;
}
/*
* NAME: jfs_rmdir(dip, dentry)
*
* FUNCTION: remove a link to child directory
*
* PARAMETER: dip - parent inode
* dentry - child directory dentry
*
* RETURN: -EINVAL - if name is . or ..
* -EINVAL - if . or .. exist but are invalid.
* errors from subroutines
*
* note:
* if other threads have the directory open when the last link
* is removed, the "." and ".." entries, if present, are removed before
* rmdir() returns and no new entries may be created in the directory,
* but the directory is not removed until the last reference to
* the directory is released (cf.unlink() of regular file).
*/
static int jfs_rmdir(struct inode *dip, struct dentry *dentry)
{
int rc;
tid_t tid; /* transaction id */
struct inode *ip = dentry->d_inode;
ino_t ino;
struct component_name dname;
struct inode *iplist[2];
struct tblock *tblk;
jfs_info("jfs_rmdir: dip:0x%p name:%s", dip, dentry->d_name.name);
/* Init inode for quota operations. */
vfs_dq_init(ip);
/* directory must be empty to be removed */
if (!dtEmpty(ip)) {
rc = -ENOTEMPTY;
goto out;
}
if ((rc = get_UCSname(&dname, dentry))) {
goto out;
}
tid = txBegin(dip->i_sb, 0);
mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
iplist[0] = dip;
iplist[1] = ip;
tblk = tid_to_tblock(tid);
tblk->xflag |= COMMIT_DELETE;
tblk->u.ip = ip;
/*
* delete the entry of target directory from parent directory
*/
ino = ip->i_ino;
if ((rc = dtDelete(tid, dip, &dname, &ino, JFS_REMOVE))) {
jfs_err("jfs_rmdir: dtDelete returned %d", rc);
if (rc == -EIO)
txAbort(tid, 1);
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
mutex_unlock(&JFS_IP(dip)->commit_mutex);
goto out2;
}
/* update parent directory's link count corresponding
* to ".." entry of the target directory deleted
*/
dip->i_ctime = dip->i_mtime = CURRENT_TIME;
inode_dec_link_count(dip);
/*
* OS/2 could have created EA and/or ACL
*/
/* free EA from both persistent and working map */
if (JFS_IP(ip)->ea.flag & DXD_EXTENT) {
/* free EA pages */
txEA(tid, ip, &JFS_IP(ip)->ea, NULL);
}
JFS_IP(ip)->ea.flag = 0;
/* free ACL from both persistent and working map */
if (JFS_IP(ip)->acl.flag & DXD_EXTENT) {
/* free ACL pages */
txEA(tid, ip, &JFS_IP(ip)->acl, NULL);
}
JFS_IP(ip)->acl.flag = 0;
/* mark the target directory as deleted */
clear_nlink(ip);
mark_inode_dirty(ip);
rc = txCommit(tid, 2, &iplist[0], 0);
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
mutex_unlock(&JFS_IP(dip)->commit_mutex);
/*
* Truncating the directory index table is not guaranteed. It
* may need to be done iteratively
*/
if (test_cflag(COMMIT_Stale, dip)) {
if (dip->i_size > 1)
jfs_truncate_nolock(dip, 0);
clear_cflag(COMMIT_Stale, dip);
}
out2:
free_UCSname(&dname);
out:
jfs_info("jfs_rmdir: rc:%d", rc);
return rc;
}
/*
* NAME: jfs_unlink(dip, dentry)
*
* FUNCTION: remove a link to object <vp> named by <name>
* from parent directory <dvp>
*
* PARAMETER: dip - inode of parent directory
* dentry - dentry of object to be removed
*
* RETURN: errors from subroutines
*
* note:
* temporary file: if one or more processes have the file open
* when the last link is removed, the link will be removed before
* unlink() returns, but the removal of the file contents will be
* postponed until all references to the files are closed.
*
* JFS does NOT support unlink() on directories.
*
*/
static int jfs_unlink(struct inode *dip, struct dentry *dentry)
{
int rc;
tid_t tid; /* transaction id */
struct inode *ip = dentry->d_inode;
ino_t ino;
struct component_name dname; /* object name */
struct inode *iplist[2];
struct tblock *tblk;
s64 new_size = 0;
int commit_flag;
jfs_info("jfs_unlink: dip:0x%p name:%s", dip, dentry->d_name.name);
/* Init inode for quota operations. */
vfs_dq_init(ip);
if ((rc = get_UCSname(&dname, dentry)))
goto out;
IWRITE_LOCK(ip, RDWRLOCK_NORMAL);
tid = txBegin(dip->i_sb, 0);
mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
iplist[0] = dip;
iplist[1] = ip;
/*
* delete the entry of target file from parent directory
*/
ino = ip->i_ino;
if ((rc = dtDelete(tid, dip, &dname, &ino, JFS_REMOVE))) {
jfs_err("jfs_unlink: dtDelete returned %d", rc);
if (rc == -EIO)
txAbort(tid, 1); /* Marks FS Dirty */
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
mutex_unlock(&JFS_IP(dip)->commit_mutex);
IWRITE_UNLOCK(ip);
goto out1;
}
ASSERT(ip->i_nlink);
ip->i_ctime = dip->i_ctime = dip->i_mtime = CURRENT_TIME;
mark_inode_dirty(dip);
/* update target's inode */
inode_dec_link_count(ip);
/*
* commit zero link count object
*/
if (ip->i_nlink == 0) {
assert(!test_cflag(COMMIT_Nolink, ip));
/* free block resources */
if ((new_size = commitZeroLink(tid, ip)) < 0) {
txAbort(tid, 1); /* Marks FS Dirty */
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
mutex_unlock(&JFS_IP(dip)->commit_mutex);
IWRITE_UNLOCK(ip);
rc = new_size;
goto out1;
}
tblk = tid_to_tblock(tid);
tblk->xflag |= COMMIT_DELETE;
tblk->u.ip = ip;
}
/*
* Incomplete truncate of file data can
* result in timing problems unless we synchronously commit the
* transaction.
*/
if (new_size)
commit_flag = COMMIT_SYNC;
else
commit_flag = 0;
/*
* If xtTruncate was incomplete, commit synchronously to avoid
* timing complications
*/
rc = txCommit(tid, 2, &iplist[0], commit_flag);
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
mutex_unlock(&JFS_IP(dip)->commit_mutex);
while (new_size && (rc == 0)) {
tid = txBegin(dip->i_sb, 0);
mutex_lock(&JFS_IP(ip)->commit_mutex);
new_size = xtTruncate_pmap(tid, ip, new_size);
if (new_size < 0) {
txAbort(tid, 1); /* Marks FS Dirty */
rc = new_size;
} else
rc = txCommit(tid, 2, &iplist[0], COMMIT_SYNC);
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
}
if (ip->i_nlink == 0)
set_cflag(COMMIT_Nolink, ip);
IWRITE_UNLOCK(ip);
/*
* Truncating the directory index table is not guaranteed. It
* may need to be done iteratively
*/
if (test_cflag(COMMIT_Stale, dip)) {
if (dip->i_size > 1)
jfs_truncate_nolock(dip, 0);
clear_cflag(COMMIT_Stale, dip);
}
out1:
free_UCSname(&dname);
out:
jfs_info("jfs_unlink: rc:%d", rc);
return rc;
}
/*
* NAME: commitZeroLink()
*
* FUNCTION: for non-directory, called by jfs_remove(),
* truncate a regular file, directory or symbolic
* link to zero length. return 0 if type is not
* one of these.
*
* if the file is currently associated with a VM segment
* only permanent disk and inode map resources are freed,
* and neither the inode nor indirect blocks are modified
* so that the resources can be later freed in the work
* map by ctrunc1.
* if there is no VM segment on entry, the resources are
* freed in both work and permanent map.
* (? for temporary file - memory object is cached even
* after no reference:
* reference count > 0 - )
*
* PARAMETERS: cd - pointer to commit data structure.
* current inode is the one to truncate.
*
* RETURN: Errors from subroutines
*/
static s64 commitZeroLink(tid_t tid, struct inode *ip)
{
int filetype;
struct tblock *tblk;
jfs_info("commitZeroLink: tid = %d, ip = 0x%p", tid, ip);
filetype = ip->i_mode & S_IFMT;
switch (filetype) {
case S_IFREG:
break;
case S_IFLNK:
/* fast symbolic link */
if (ip->i_size < IDATASIZE) {
ip->i_size = 0;
return 0;
}
break;
default:
assert(filetype != S_IFDIR);
return 0;
}
set_cflag(COMMIT_Freewmap, ip);
/* mark transaction of block map update type */
tblk = tid_to_tblock(tid);
tblk->xflag |= COMMIT_PMAP;
/*
* free EA
*/
if (JFS_IP(ip)->ea.flag & DXD_EXTENT)
/* acquire maplock on EA to be freed from block map */
txEA(tid, ip, &JFS_IP(ip)->ea, NULL);
/*
* free ACL
*/
if (JFS_IP(ip)->acl.flag & DXD_EXTENT)
/* acquire maplock on EA to be freed from block map */
txEA(tid, ip, &JFS_IP(ip)->acl, NULL);
/*
* free xtree/data (truncate to zero length):
* free xtree/data pages from cache if COMMIT_PWMAP,
* free xtree/data blocks from persistent block map, and
* free xtree/data blocks from working block map if COMMIT_PWMAP;
*/
if (ip->i_size)
return xtTruncate_pmap(tid, ip, 0);
return 0;
}
/*
* NAME: jfs_free_zero_link()
*
* FUNCTION: for non-directory, called by iClose(),
* free resources of a file from cache and WORKING map
* for a file previously committed with zero link count
* while associated with a pager object,
*
* PARAMETER: ip - pointer to inode of file.
*/
void jfs_free_zero_link(struct inode *ip)
{
int type;
jfs_info("jfs_free_zero_link: ip = 0x%p", ip);
/* return if not reg or symbolic link or if size is
* already ok.
*/
type = ip->i_mode & S_IFMT;
switch (type) {
case S_IFREG:
break;
case S_IFLNK:
/* if its contained in inode nothing to do */
if (ip->i_size < IDATASIZE)
return;
break;
default:
return;
}
/*
* free EA
*/
if (JFS_IP(ip)->ea.flag & DXD_EXTENT) {
s64 xaddr = addressDXD(&JFS_IP(ip)->ea);
int xlen = lengthDXD(&JFS_IP(ip)->ea);
struct maplock maplock; /* maplock for COMMIT_WMAP */
struct pxd_lock *pxdlock; /* maplock for COMMIT_WMAP */
/* free EA pages from cache */
invalidate_dxd_metapages(ip, JFS_IP(ip)->ea);
/* free EA extent from working block map */
maplock.index = 1;
pxdlock = (struct pxd_lock *) & maplock;
pxdlock->flag = mlckFREEPXD;
PXDaddress(&pxdlock->pxd, xaddr);
PXDlength(&pxdlock->pxd, xlen);
txFreeMap(ip, pxdlock, NULL, COMMIT_WMAP);
}
/*
* free ACL
*/
if (JFS_IP(ip)->acl.flag & DXD_EXTENT) {
s64 xaddr = addressDXD(&JFS_IP(ip)->acl);
int xlen = lengthDXD(&JFS_IP(ip)->acl);
struct maplock maplock; /* maplock for COMMIT_WMAP */
struct pxd_lock *pxdlock; /* maplock for COMMIT_WMAP */
invalidate_dxd_metapages(ip, JFS_IP(ip)->acl);
/* free ACL extent from working block map */
maplock.index = 1;
pxdlock = (struct pxd_lock *) & maplock;
pxdlock->flag = mlckFREEPXD;
PXDaddress(&pxdlock->pxd, xaddr);
PXDlength(&pxdlock->pxd, xlen);
txFreeMap(ip, pxdlock, NULL, COMMIT_WMAP);
}
/*
* free xtree/data (truncate to zero length):
* free xtree/data pages from cache, and
* free xtree/data blocks from working block map;
*/
if (ip->i_size)
xtTruncate(0, ip, 0, COMMIT_WMAP);
}
/*
* NAME: jfs_link(vp, dvp, name, crp)
*
* FUNCTION: create a link to <vp> by the name = <name>
* in the parent directory <dvp>
*
* PARAMETER: vp - target object
* dvp - parent directory of new link
* name - name of new link to target object
* crp - credential
*
* RETURN: Errors from subroutines
*
* note:
* JFS does NOT support link() on directories (to prevent circular
* path in the directory hierarchy);
* EPERM: the target object is a directory, and either the caller
* does not have appropriate privileges or the implementation prohibits
* using link() on directories [XPG4.2].
*
* JFS does NOT support links between file systems:
* EXDEV: target object and new link are on different file systems and
* implementation does not support links between file systems [XPG4.2].
*/
static int jfs_link(struct dentry *old_dentry,
struct inode *dir, struct dentry *dentry)
{
int rc;
tid_t tid;
struct inode *ip = old_dentry->d_inode;
ino_t ino;
struct component_name dname;
struct btstack btstack;
struct inode *iplist[2];
jfs_info("jfs_link: %s %s", old_dentry->d_name.name,
dentry->d_name.name);
if (ip->i_nlink == JFS_LINK_MAX)
return -EMLINK;
if (ip->i_nlink == 0)
return -ENOENT;
tid = txBegin(ip->i_sb, 0);
mutex_lock_nested(&JFS_IP(dir)->commit_mutex, COMMIT_MUTEX_PARENT);
mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
/*
* scan parent directory for entry/freespace
*/
if ((rc = get_UCSname(&dname, dentry)))
goto out;
if ((rc = dtSearch(dir, &dname, &ino, &btstack, JFS_CREATE)))
goto free_dname;
/*
* create entry for new link in parent directory
*/
ino = ip->i_ino;
if ((rc = dtInsert(tid, dir, &dname, &ino, &btstack)))
goto free_dname;
/* update object inode */
inc_nlink(ip); /* for new link */
ip->i_ctime = CURRENT_TIME;
dir->i_ctime = dir->i_mtime = CURRENT_TIME;
mark_inode_dirty(dir);
atomic_inc(&ip->i_count);
iplist[0] = ip;
iplist[1] = dir;
rc = txCommit(tid, 2, &iplist[0], 0);
if (rc) {
ip->i_nlink--; /* never instantiated */
iput(ip);
} else
d_instantiate(dentry, ip);
free_dname:
free_UCSname(&dname);
out:
txEnd(tid);
mutex_unlock(&JFS_IP(ip)->commit_mutex);
mutex_unlock(&JFS_IP(dir)->commit_mutex);
jfs_info("jfs_link: rc:%d", rc);
return rc;
}
/*
* NAME: jfs_symlink(dip, dentry, name)
*
* FUNCTION: creates a symbolic link to <symlink> by name <name>
* in directory <dip>
*
* PARAMETER: dip - parent directory vnode
* dentry - dentry of symbolic link
* name - the path name of the existing object
* that will be the source of the link
*
* RETURN: errors from subroutines
*
* note:
* ENAMETOOLONG: pathname resolution of a symbolic link produced
* an intermediate result whose length exceeds PATH_MAX [XPG4.2]
*/
static int jfs_symlink(struct inode *dip, struct dentry *dentry,
const char *name)
{
int rc;
tid_t tid;
ino_t ino = 0;
struct component_name dname;
int ssize; /* source pathname size */
struct btstack btstack;
struct inode *ip = dentry->d_inode;
unchar *i_fastsymlink;
s64 xlen = 0;
int bmask = 0, xsize;
s64 extent = 0, xaddr;
struct metapage *mp;
struct super_block *sb;
struct tblock *tblk;
struct inode *iplist[2];
jfs_info("jfs_symlink: dip:0x%p name:%s", dip, name);
ssize = strlen(name) + 1;
/*
* search parent directory for entry/freespace
* (dtSearch() returns parent directory page pinned)
*/
if ((rc = get_UCSname(&dname, dentry)))
goto out1;
/*
* allocate on-disk/in-memory inode for symbolic link:
* (iAlloc() returns new, locked inode)
*/
ip = ialloc(dip, S_IFLNK | 0777);
if (IS_ERR(ip)) {
rc = PTR_ERR(ip);
goto out2;
}
tid = txBegin(dip->i_sb, 0);
mutex_lock_nested(&JFS_IP(dip)->commit_mutex, COMMIT_MUTEX_PARENT);
mutex_lock_nested(&JFS_IP(ip)->commit_mutex, COMMIT_MUTEX_CHILD);
rc = jfs_init_security(tid, ip, dip);
if (rc)
goto out3;
tblk = tid_to_tblock(tid);
tblk->xflag |= COMMIT_CREATE;
tblk->ino = ip->i_ino;
tblk->u.ixpxd = JFS_IP(ip)->ixpxd;
/* fix symlink access permission
* (dir_create() ANDs in the u.u_cmask,
* but symlinks really need to be 777 access)
*/
ip->i_mode |= 0777;
/*
* write symbolic link target path name
*/
xtInitRoot(tid, ip);
/*
* write source path name inline in on-disk inode (fast symbolic link)
*/
if (ssize <= IDATASIZE) {
ip->i_op = &jfs_symlink_inode_operations;
i_fastsymlink = JFS_IP(ip)->i_inline;
memcpy(i_fastsymlink, name, ssize);
ip->i_size = ssize - 1;
/*
* if symlink is > 128 bytes, we don't have the space to
* store inline extended attributes
*/
if (ssize > sizeof (JFS_IP(ip)->i_inline))
JFS_IP(ip)->mode2 &= ~INLINEEA;
jfs_info("jfs_symlink: fast symlink added ssize:%d name:%s ",
ssize, name);
}
/*
* write source path name in a single extent
*/
else {
jfs_info("jfs_symlink: allocate extent ip:0x%p", ip);
ip->i_op = &page_symlink_inode_operations;
ip->i_mapping->a_ops = &jfs_aops;
/*
* even though the data of symlink object (source
* path name) is treated as non-journaled user data,
* it is read/written thru buffer cache for performance.
*/
sb = ip->i_sb;
bmask = JFS_SBI(sb)->bsize - 1;
xsize = (ssize + bmask) & ~bmask;
xaddr = 0;
xlen = xsize >> JFS_SBI(sb)->l2bsize;
if ((rc = xtInsert(tid, ip, 0, 0, xlen, &xaddr, 0))) {
txAbort(tid, 0);
goto out3;
}
extent = xaddr;
ip->i_size = ssize - 1;
while (ssize) {
/* This is kind of silly since PATH_MAX == 4K */
int copy_size = min(ssize, PSIZE);
mp = get_metapage(ip, xaddr, PSIZE, 1);
if (mp == NULL) {
xtTruncate(tid, ip, 0, COMMIT_PWMAP);
rc = -EIO;
txAbort(tid, 0);
goto out3;