mirror_zfs/module/os/linux/zfs/zfs_vnops_os.c
Sanjeev Bagewadi 3cf2bfa570 Allocate zap_attribute_t from kmem instead of stack
This patch is preparatory work for long name feature. It changes all
users of zap_attribute_t to allocate it from kmem instead of stack. It
also make zap_attribute_t and zap_name_t structure variable length.

Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Chunwei Chen <david.chen@nutanix.com>
Closes #15921
2024-10-01 13:39:08 -07:00

4329 lines
107 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or https://opensource.org/licenses/CDDL-1.0.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2018 by Delphix. All rights reserved.
* Copyright (c) 2015 by Chunwei Chen. All rights reserved.
* Copyright 2017 Nexenta Systems, Inc.
*/
/* Portions Copyright 2007 Jeremy Teo */
/* Portions Copyright 2010 Robert Milkowski */
#include <sys/types.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/sysmacros.h>
#include <sys/vfs.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/kmem.h>
#include <sys/taskq.h>
#include <sys/uio.h>
#include <sys/vmsystm.h>
#include <sys/atomic.h>
#include <sys/pathname.h>
#include <sys/cmn_err.h>
#include <sys/errno.h>
#include <sys/zfs_dir.h>
#include <sys/zfs_acl.h>
#include <sys/zfs_ioctl.h>
#include <sys/fs/zfs.h>
#include <sys/dmu.h>
#include <sys/dmu_objset.h>
#include <sys/spa.h>
#include <sys/txg.h>
#include <sys/dbuf.h>
#include <sys/zap.h>
#include <sys/sa.h>
#include <sys/policy.h>
#include <sys/sunddi.h>
#include <sys/sid.h>
#include <sys/zfs_ctldir.h>
#include <sys/zfs_fuid.h>
#include <sys/zfs_quota.h>
#include <sys/zfs_sa.h>
#include <sys/zfs_vnops.h>
#include <sys/zfs_rlock.h>
#include <sys/cred.h>
#include <sys/zpl.h>
#include <sys/zil.h>
#include <sys/sa_impl.h>
#include <linux/mm_compat.h>
/*
* Programming rules.
*
* Each vnode op performs some logical unit of work. To do this, the ZPL must
* properly lock its in-core state, create a DMU transaction, do the work,
* record this work in the intent log (ZIL), commit the DMU transaction,
* and wait for the intent log to commit if it is a synchronous operation.
* Moreover, the vnode ops must work in both normal and log replay context.
* The ordering of events is important to avoid deadlocks and references
* to freed memory. The example below illustrates the following Big Rules:
*
* (1) A check must be made in each zfs thread for a mounted file system.
* This is done avoiding races using zfs_enter(zfsvfs).
* A zfs_exit(zfsvfs) is needed before all returns. Any znodes
* must be checked with zfs_verify_zp(zp). Both of these macros
* can return EIO from the calling function.
*
* (2) zrele() should always be the last thing except for zil_commit() (if
* necessary) and zfs_exit(). This is for 3 reasons: First, if it's the
* last reference, the vnode/znode can be freed, so the zp may point to
* freed memory. Second, the last reference will call zfs_zinactive(),
* which may induce a lot of work -- pushing cached pages (which acquires
* range locks) and syncing out cached atime changes. Third,
* zfs_zinactive() may require a new tx, which could deadlock the system
* if you were already holding one. This deadlock occurs because the tx
* currently being operated on prevents a txg from syncing, which
* prevents the new tx from progressing, resulting in a deadlock. If you
* must call zrele() within a tx, use zfs_zrele_async(). Note that iput()
* is a synonym for zrele().
*
* (3) All range locks must be grabbed before calling dmu_tx_assign(),
* as they can span dmu_tx_assign() calls.
*
* (4) If ZPL locks are held, pass TXG_NOWAIT as the second argument to
* dmu_tx_assign(). This is critical because we don't want to block
* while holding locks.
*
* If no ZPL locks are held (aside from zfs_enter()), use TXG_WAIT. This
* reduces lock contention and CPU usage when we must wait (note that if
* throughput is constrained by the storage, nearly every transaction
* must wait).
*
* Note, in particular, that if a lock is sometimes acquired before
* the tx assigns, and sometimes after (e.g. z_lock), then failing
* to use a non-blocking assign can deadlock the system. The scenario:
*
* Thread A has grabbed a lock before calling dmu_tx_assign().
* Thread B is in an already-assigned tx, and blocks for this lock.
* Thread A calls dmu_tx_assign(TXG_WAIT) and blocks in txg_wait_open()
* forever, because the previous txg can't quiesce until B's tx commits.
*
* If dmu_tx_assign() returns ERESTART and zfsvfs->z_assign is TXG_NOWAIT,
* then drop all locks, call dmu_tx_wait(), and try again. On subsequent
* calls to dmu_tx_assign(), pass TXG_NOTHROTTLE in addition to TXG_NOWAIT,
* to indicate that this operation has already called dmu_tx_wait().
* This will ensure that we don't retry forever, waiting a short bit
* each time.
*
* (5) If the operation succeeded, generate the intent log entry for it
* before dropping locks. This ensures that the ordering of events
* in the intent log matches the order in which they actually occurred.
* During ZIL replay the zfs_log_* functions will update the sequence
* number to indicate the zil transaction has replayed.
*
* (6) At the end of each vnode op, the DMU tx must always commit,
* regardless of whether there were any errors.
*
* (7) After dropping all locks, invoke zil_commit(zilog, foid)
* to ensure that synchronous semantics are provided when necessary.
*
* In general, this is how things should be ordered in each vnode op:
*
* zfs_enter(zfsvfs); // exit if unmounted
* top:
* zfs_dirent_lock(&dl, ...) // lock directory entry (may igrab())
* rw_enter(...); // grab any other locks you need
* tx = dmu_tx_create(...); // get DMU tx
* dmu_tx_hold_*(); // hold each object you might modify
* error = dmu_tx_assign(tx, (waited ? TXG_NOTHROTTLE : 0) | TXG_NOWAIT);
* if (error) {
* rw_exit(...); // drop locks
* zfs_dirent_unlock(dl); // unlock directory entry
* zrele(...); // release held znodes
* if (error == ERESTART) {
* waited = B_TRUE;
* dmu_tx_wait(tx);
* dmu_tx_abort(tx);
* goto top;
* }
* dmu_tx_abort(tx); // abort DMU tx
* zfs_exit(zfsvfs); // finished in zfs
* return (error); // really out of space
* }
* error = do_real_work(); // do whatever this VOP does
* if (error == 0)
* zfs_log_*(...); // on success, make ZIL entry
* dmu_tx_commit(tx); // commit DMU tx -- error or not
* rw_exit(...); // drop locks
* zfs_dirent_unlock(dl); // unlock directory entry
* zrele(...); // release held znodes
* zil_commit(zilog, foid); // synchronous when necessary
* zfs_exit(zfsvfs); // finished in zfs
* return (error); // done, report error
*/
int
zfs_open(struct inode *ip, int mode, int flag, cred_t *cr)
{
(void) cr;
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
int error;
if ((error = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (error);
/* Honor ZFS_APPENDONLY file attribute */
if (blk_mode_is_open_write(mode) && (zp->z_pflags & ZFS_APPENDONLY) &&
((flag & O_APPEND) == 0)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EPERM));
}
/*
* Keep a count of the synchronous opens in the znode. On first
* synchronous open we must convert all previous async transactions
* into sync to keep correct ordering.
*/
if (flag & O_SYNC) {
if (atomic_inc_32_nv(&zp->z_sync_cnt) == 1)
zil_async_to_sync(zfsvfs->z_log, zp->z_id);
}
zfs_exit(zfsvfs, FTAG);
return (0);
}
int
zfs_close(struct inode *ip, int flag, cred_t *cr)
{
(void) cr;
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
int error;
if ((error = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (error);
/* Decrement the synchronous opens in the znode */
if (flag & O_SYNC)
atomic_dec_32(&zp->z_sync_cnt);
zfs_exit(zfsvfs, FTAG);
return (0);
}
#if defined(_KERNEL)
static int zfs_fillpage(struct inode *ip, struct page *pp);
/*
* When a file is memory mapped, we must keep the IO data synchronized
* between the DMU cache and the memory mapped pages. Update all mapped
* pages with the contents of the coresponding dmu buffer.
*/
void
update_pages(znode_t *zp, int64_t start, int len, objset_t *os)
{
struct address_space *mp = ZTOI(zp)->i_mapping;
int64_t off = start & (PAGE_SIZE - 1);
for (start &= PAGE_MASK; len > 0; start += PAGE_SIZE) {
uint64_t nbytes = MIN(PAGE_SIZE - off, len);
struct page *pp = find_lock_page(mp, start >> PAGE_SHIFT);
if (pp) {
if (mapping_writably_mapped(mp))
flush_dcache_page(pp);
void *pb = kmap(pp);
int error = dmu_read(os, zp->z_id, start + off,
nbytes, pb + off, DMU_READ_PREFETCH);
kunmap(pp);
if (error) {
SetPageError(pp);
ClearPageUptodate(pp);
} else {
ClearPageError(pp);
SetPageUptodate(pp);
if (!PagePrivate(pp)) {
/*
* Set private bit so page migration
* will wait for us to finish writeback
* before calling migrate_folio().
*/
SetPagePrivate(pp);
get_page(pp);
}
if (mapping_writably_mapped(mp))
flush_dcache_page(pp);
mark_page_accessed(pp);
}
unlock_page(pp);
put_page(pp);
}
len -= nbytes;
off = 0;
}
}
/*
* When a file is memory mapped, we must keep the I/O data synchronized
* between the DMU cache and the memory mapped pages. Preferentially read
* from memory mapped pages, otherwise fallback to reading through the dmu.
*/
int
mappedread(znode_t *zp, int nbytes, zfs_uio_t *uio)
{
struct inode *ip = ZTOI(zp);
struct address_space *mp = ip->i_mapping;
int64_t start = uio->uio_loffset;
int64_t off = start & (PAGE_SIZE - 1);
int len = nbytes;
int error = 0;
for (start &= PAGE_MASK; len > 0; start += PAGE_SIZE) {
uint64_t bytes = MIN(PAGE_SIZE - off, len);
struct page *pp = find_lock_page(mp, start >> PAGE_SHIFT);
if (pp) {
/*
* If filemap_fault() retries there exists a window
* where the page will be unlocked and not up to date.
* In this case we must try and fill the page.
*/
if (unlikely(!PageUptodate(pp))) {
error = zfs_fillpage(ip, pp);
if (error) {
unlock_page(pp);
put_page(pp);
return (error);
}
}
ASSERT(PageUptodate(pp) || PageDirty(pp));
unlock_page(pp);
void *pb = kmap(pp);
error = zfs_uiomove(pb + off, bytes, UIO_READ, uio);
kunmap(pp);
if (mapping_writably_mapped(mp))
flush_dcache_page(pp);
mark_page_accessed(pp);
put_page(pp);
} else {
error = dmu_read_uio_dbuf(sa_get_db(zp->z_sa_hdl),
uio, bytes);
}
len -= bytes;
off = 0;
if (error)
break;
}
return (error);
}
#endif /* _KERNEL */
static unsigned long zfs_delete_blocks = DMU_MAX_DELETEBLKCNT;
/*
* Write the bytes to a file.
*
* IN: zp - znode of file to be written to
* data - bytes to write
* len - number of bytes to write
* pos - offset to start writing at
*
* OUT: resid - remaining bytes to write
*
* RETURN: 0 if success
* positive error code if failure. EIO is returned
* for a short write when residp isn't provided.
*
* Timestamps:
* zp - ctime|mtime updated if byte count > 0
*/
int
zfs_write_simple(znode_t *zp, const void *data, size_t len,
loff_t pos, size_t *residp)
{
fstrans_cookie_t cookie;
int error;
struct iovec iov;
iov.iov_base = (void *)data;
iov.iov_len = len;
zfs_uio_t uio;
zfs_uio_iovec_init(&uio, &iov, 1, pos, UIO_SYSSPACE, len, 0);
cookie = spl_fstrans_mark();
error = zfs_write(zp, &uio, 0, kcred);
spl_fstrans_unmark(cookie);
if (error == 0) {
if (residp != NULL)
*residp = zfs_uio_resid(&uio);
else if (zfs_uio_resid(&uio) != 0)
error = SET_ERROR(EIO);
}
return (error);
}
static void
zfs_rele_async_task(void *arg)
{
iput(arg);
}
void
zfs_zrele_async(znode_t *zp)
{
struct inode *ip = ZTOI(zp);
objset_t *os = ITOZSB(ip)->z_os;
ASSERT(atomic_read(&ip->i_count) > 0);
ASSERT(os != NULL);
/*
* If decrementing the count would put us at 0, we can't do it inline
* here, because that would be synchronous. Instead, dispatch an iput
* to run later.
*
* For more information on the dangers of a synchronous iput, see the
* header comment of this file.
*/
if (!atomic_add_unless(&ip->i_count, -1, 1)) {
VERIFY(taskq_dispatch(dsl_pool_zrele_taskq(dmu_objset_pool(os)),
zfs_rele_async_task, ip, TQ_SLEEP) != TASKQID_INVALID);
}
}
/*
* Lookup an entry in a directory, or an extended attribute directory.
* If it exists, return a held inode reference for it.
*
* IN: zdp - znode of directory to search.
* nm - name of entry to lookup.
* flags - LOOKUP_XATTR set if looking for an attribute.
* cr - credentials of caller.
* direntflags - directory lookup flags
* realpnp - returned pathname.
*
* OUT: zpp - znode of located entry, NULL if not found.
*
* RETURN: 0 on success, error code on failure.
*
* Timestamps:
* NA
*/
int
zfs_lookup(znode_t *zdp, char *nm, znode_t **zpp, int flags, cred_t *cr,
int *direntflags, pathname_t *realpnp)
{
zfsvfs_t *zfsvfs = ZTOZSB(zdp);
int error = 0;
/*
* Fast path lookup, however we must skip DNLC lookup
* for case folding or normalizing lookups because the
* DNLC code only stores the passed in name. This means
* creating 'a' and removing 'A' on a case insensitive
* file system would work, but DNLC still thinks 'a'
* exists and won't let you create it again on the next
* pass through fast path.
*/
if (!(flags & (LOOKUP_XATTR | FIGNORECASE))) {
if (!S_ISDIR(ZTOI(zdp)->i_mode)) {
return (SET_ERROR(ENOTDIR));
} else if (zdp->z_sa_hdl == NULL) {
return (SET_ERROR(EIO));
}
if (nm[0] == 0 || (nm[0] == '.' && nm[1] == '\0')) {
error = zfs_fastaccesschk_execute(zdp, cr);
if (!error) {
*zpp = zdp;
zhold(*zpp);
return (0);
}
return (error);
}
}
if ((error = zfs_enter_verify_zp(zfsvfs, zdp, FTAG)) != 0)
return (error);
*zpp = NULL;
if (flags & LOOKUP_XATTR) {
/*
* We don't allow recursive attributes..
* Maybe someday we will.
*/
if (zdp->z_pflags & ZFS_XATTR) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EINVAL));
}
if ((error = zfs_get_xattrdir(zdp, zpp, cr, flags))) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Do we have permission to get into attribute directory?
*/
if ((error = zfs_zaccess(*zpp, ACE_EXECUTE, 0,
B_TRUE, cr, zfs_init_idmap))) {
zrele(*zpp);
*zpp = NULL;
}
zfs_exit(zfsvfs, FTAG);
return (error);
}
if (!S_ISDIR(ZTOI(zdp)->i_mode)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(ENOTDIR));
}
/*
* Check accessibility of directory.
*/
if ((error = zfs_zaccess(zdp, ACE_EXECUTE, 0, B_FALSE, cr,
zfs_init_idmap))) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
if (zfsvfs->z_utf8 && u8_validate(nm, strlen(nm),
NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EILSEQ));
}
error = zfs_dirlook(zdp, nm, zpp, flags, direntflags, realpnp);
if ((error == 0) && (*zpp))
zfs_znode_update_vfs(*zpp);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Attempt to create a new entry in a directory. If the entry
* already exists, truncate the file if permissible, else return
* an error. Return the ip of the created or trunc'd file.
*
* IN: dzp - znode of directory to put new file entry in.
* name - name of new file entry.
* vap - attributes of new file.
* excl - flag indicating exclusive or non-exclusive mode.
* mode - mode to open file with.
* cr - credentials of caller.
* flag - file flag.
* vsecp - ACL to be set
* mnt_ns - user namespace of the mount
*
* OUT: zpp - znode of created or trunc'd entry.
*
* RETURN: 0 on success, error code on failure.
*
* Timestamps:
* dzp - ctime|mtime updated if new entry created
* zp - ctime|mtime always, atime if new
*/
int
zfs_create(znode_t *dzp, char *name, vattr_t *vap, int excl,
int mode, znode_t **zpp, cred_t *cr, int flag, vsecattr_t *vsecp,
zidmap_t *mnt_ns)
{
znode_t *zp;
zfsvfs_t *zfsvfs = ZTOZSB(dzp);
zilog_t *zilog;
objset_t *os;
zfs_dirlock_t *dl;
dmu_tx_t *tx;
int error;
uid_t uid;
gid_t gid;
zfs_acl_ids_t acl_ids;
boolean_t fuid_dirtied;
boolean_t have_acl = B_FALSE;
boolean_t waited = B_FALSE;
boolean_t skip_acl = (flag & ATTR_NOACLCHECK) ? B_TRUE : B_FALSE;
/*
* If we have an ephemeral id, ACL, or XVATTR then
* make sure file system is at proper version
*/
gid = crgetgid(cr);
uid = crgetuid(cr);
if (zfsvfs->z_use_fuids == B_FALSE &&
(vsecp || IS_EPHEMERAL(uid) || IS_EPHEMERAL(gid)))
return (SET_ERROR(EINVAL));
if (name == NULL)
return (SET_ERROR(EINVAL));
if ((error = zfs_enter_verify_zp(zfsvfs, dzp, FTAG)) != 0)
return (error);
os = zfsvfs->z_os;
zilog = zfsvfs->z_log;
if (zfsvfs->z_utf8 && u8_validate(name, strlen(name),
NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EILSEQ));
}
if (vap->va_mask & ATTR_XVATTR) {
if ((error = secpolicy_xvattr((xvattr_t *)vap,
crgetuid(cr), cr, vap->va_mode)) != 0) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
}
top:
*zpp = NULL;
if (*name == '\0') {
/*
* Null component name refers to the directory itself.
*/
zhold(dzp);
zp = dzp;
dl = NULL;
error = 0;
} else {
/* possible igrab(zp) */
int zflg = 0;
if (flag & FIGNORECASE)
zflg |= ZCILOOK;
error = zfs_dirent_lock(&dl, dzp, name, &zp, zflg,
NULL, NULL);
if (error) {
if (have_acl)
zfs_acl_ids_free(&acl_ids);
if (strcmp(name, "..") == 0)
error = SET_ERROR(EISDIR);
zfs_exit(zfsvfs, FTAG);
return (error);
}
}
if (zp == NULL) {
uint64_t txtype;
uint64_t projid = ZFS_DEFAULT_PROJID;
/*
* Create a new file object and update the directory
* to reference it.
*/
if ((error = zfs_zaccess(dzp, ACE_ADD_FILE, 0, skip_acl, cr,
mnt_ns))) {
if (have_acl)
zfs_acl_ids_free(&acl_ids);
goto out;
}
/*
* We only support the creation of regular files in
* extended attribute directories.
*/
if ((dzp->z_pflags & ZFS_XATTR) && !S_ISREG(vap->va_mode)) {
if (have_acl)
zfs_acl_ids_free(&acl_ids);
error = SET_ERROR(EINVAL);
goto out;
}
if (!have_acl && (error = zfs_acl_ids_create(dzp, 0, vap,
cr, vsecp, &acl_ids, mnt_ns)) != 0)
goto out;
have_acl = B_TRUE;
if (S_ISREG(vap->va_mode) || S_ISDIR(vap->va_mode))
projid = zfs_inherit_projid(dzp);
if (zfs_acl_ids_overquota(zfsvfs, &acl_ids, projid)) {
zfs_acl_ids_free(&acl_ids);
error = SET_ERROR(EDQUOT);
goto out;
}
tx = dmu_tx_create(os);
dmu_tx_hold_sa_create(tx, acl_ids.z_aclp->z_acl_bytes +
ZFS_SA_BASE_ATTR_SIZE);
fuid_dirtied = zfsvfs->z_fuid_dirty;
if (fuid_dirtied)
zfs_fuid_txhold(zfsvfs, tx);
dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name);
dmu_tx_hold_sa(tx, dzp->z_sa_hdl, B_FALSE);
if (!zfsvfs->z_use_sa &&
acl_ids.z_aclp->z_acl_bytes > ZFS_ACE_SPACE) {
dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
0, acl_ids.z_aclp->z_acl_bytes);
}
error = dmu_tx_assign(tx,
(waited ? TXG_NOTHROTTLE : 0) | TXG_NOWAIT);
if (error) {
zfs_dirent_unlock(dl);
if (error == ERESTART) {
waited = B_TRUE;
dmu_tx_wait(tx);
dmu_tx_abort(tx);
goto top;
}
zfs_acl_ids_free(&acl_ids);
dmu_tx_abort(tx);
zfs_exit(zfsvfs, FTAG);
return (error);
}
zfs_mknode(dzp, vap, tx, cr, 0, &zp, &acl_ids);
error = zfs_link_create(dl, zp, tx, ZNEW);
if (error != 0) {
/*
* Since, we failed to add the directory entry for it,
* delete the newly created dnode.
*/
zfs_znode_delete(zp, tx);
remove_inode_hash(ZTOI(zp));
zfs_acl_ids_free(&acl_ids);
dmu_tx_commit(tx);
goto out;
}
if (fuid_dirtied)
zfs_fuid_sync(zfsvfs, tx);
txtype = zfs_log_create_txtype(Z_FILE, vsecp, vap);
if (flag & FIGNORECASE)
txtype |= TX_CI;
zfs_log_create(zilog, tx, txtype, dzp, zp, name,
vsecp, acl_ids.z_fuidp, vap);
zfs_acl_ids_free(&acl_ids);
dmu_tx_commit(tx);
} else {
int aflags = (flag & O_APPEND) ? V_APPEND : 0;
if (have_acl)
zfs_acl_ids_free(&acl_ids);
/*
* A directory entry already exists for this name.
*/
/*
* Can't truncate an existing file if in exclusive mode.
*/
if (excl) {
error = SET_ERROR(EEXIST);
goto out;
}
/*
* Can't open a directory for writing.
*/
if (S_ISDIR(ZTOI(zp)->i_mode)) {
error = SET_ERROR(EISDIR);
goto out;
}
/*
* Verify requested access to file.
*/
if (mode && (error = zfs_zaccess_rwx(zp, mode, aflags, cr,
mnt_ns))) {
goto out;
}
mutex_enter(&dzp->z_lock);
dzp->z_seq++;
mutex_exit(&dzp->z_lock);
/*
* Truncate regular files if requested.
*/
if (S_ISREG(ZTOI(zp)->i_mode) &&
(vap->va_mask & ATTR_SIZE) && (vap->va_size == 0)) {
/* we can't hold any locks when calling zfs_freesp() */
if (dl) {
zfs_dirent_unlock(dl);
dl = NULL;
}
error = zfs_freesp(zp, 0, 0, mode, TRUE);
}
}
out:
if (dl)
zfs_dirent_unlock(dl);
if (error) {
if (zp)
zrele(zp);
} else {
zfs_znode_update_vfs(dzp);
zfs_znode_update_vfs(zp);
*zpp = zp;
}
if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
zil_commit(zilog, 0);
zfs_exit(zfsvfs, FTAG);
return (error);
}
int
zfs_tmpfile(struct inode *dip, vattr_t *vap, int excl,
int mode, struct inode **ipp, cred_t *cr, int flag, vsecattr_t *vsecp,
zidmap_t *mnt_ns)
{
(void) excl, (void) mode, (void) flag;
znode_t *zp = NULL, *dzp = ITOZ(dip);
zfsvfs_t *zfsvfs = ITOZSB(dip);
objset_t *os;
dmu_tx_t *tx;
int error;
uid_t uid;
gid_t gid;
zfs_acl_ids_t acl_ids;
uint64_t projid = ZFS_DEFAULT_PROJID;
boolean_t fuid_dirtied;
boolean_t have_acl = B_FALSE;
boolean_t waited = B_FALSE;
/*
* If we have an ephemeral id, ACL, or XVATTR then
* make sure file system is at proper version
*/
gid = crgetgid(cr);
uid = crgetuid(cr);
if (zfsvfs->z_use_fuids == B_FALSE &&
(vsecp || IS_EPHEMERAL(uid) || IS_EPHEMERAL(gid)))
return (SET_ERROR(EINVAL));
if ((error = zfs_enter_verify_zp(zfsvfs, dzp, FTAG)) != 0)
return (error);
os = zfsvfs->z_os;
if (vap->va_mask & ATTR_XVATTR) {
if ((error = secpolicy_xvattr((xvattr_t *)vap,
crgetuid(cr), cr, vap->va_mode)) != 0) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
}
top:
*ipp = NULL;
/*
* Create a new file object and update the directory
* to reference it.
*/
if ((error = zfs_zaccess(dzp, ACE_ADD_FILE, 0, B_FALSE, cr, mnt_ns))) {
if (have_acl)
zfs_acl_ids_free(&acl_ids);
goto out;
}
if (!have_acl && (error = zfs_acl_ids_create(dzp, 0, vap,
cr, vsecp, &acl_ids, mnt_ns)) != 0)
goto out;
have_acl = B_TRUE;
if (S_ISREG(vap->va_mode) || S_ISDIR(vap->va_mode))
projid = zfs_inherit_projid(dzp);
if (zfs_acl_ids_overquota(zfsvfs, &acl_ids, projid)) {
zfs_acl_ids_free(&acl_ids);
error = SET_ERROR(EDQUOT);
goto out;
}
tx = dmu_tx_create(os);
dmu_tx_hold_sa_create(tx, acl_ids.z_aclp->z_acl_bytes +
ZFS_SA_BASE_ATTR_SIZE);
dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
fuid_dirtied = zfsvfs->z_fuid_dirty;
if (fuid_dirtied)
zfs_fuid_txhold(zfsvfs, tx);
if (!zfsvfs->z_use_sa &&
acl_ids.z_aclp->z_acl_bytes > ZFS_ACE_SPACE) {
dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
0, acl_ids.z_aclp->z_acl_bytes);
}
error = dmu_tx_assign(tx, (waited ? TXG_NOTHROTTLE : 0) | TXG_NOWAIT);
if (error) {
if (error == ERESTART) {
waited = B_TRUE;
dmu_tx_wait(tx);
dmu_tx_abort(tx);
goto top;
}
zfs_acl_ids_free(&acl_ids);
dmu_tx_abort(tx);
zfs_exit(zfsvfs, FTAG);
return (error);
}
zfs_mknode(dzp, vap, tx, cr, IS_TMPFILE, &zp, &acl_ids);
if (fuid_dirtied)
zfs_fuid_sync(zfsvfs, tx);
/* Add to unlinked set */
zp->z_unlinked = B_TRUE;
zfs_unlinked_add(zp, tx);
zfs_acl_ids_free(&acl_ids);
dmu_tx_commit(tx);
out:
if (error) {
if (zp)
zrele(zp);
} else {
zfs_znode_update_vfs(dzp);
zfs_znode_update_vfs(zp);
*ipp = ZTOI(zp);
}
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Remove an entry from a directory.
*
* IN: dzp - znode of directory to remove entry from.
* name - name of entry to remove.
* cr - credentials of caller.
* flags - case flags.
*
* RETURN: 0 if success
* error code if failure
*
* Timestamps:
* dzp - ctime|mtime
* ip - ctime (if nlink > 0)
*/
static uint64_t null_xattr = 0;
int
zfs_remove(znode_t *dzp, char *name, cred_t *cr, int flags)
{
znode_t *zp;
znode_t *xzp;
zfsvfs_t *zfsvfs = ZTOZSB(dzp);
zilog_t *zilog;
uint64_t acl_obj, xattr_obj;
uint64_t xattr_obj_unlinked = 0;
uint64_t obj = 0;
uint64_t links;
zfs_dirlock_t *dl;
dmu_tx_t *tx;
boolean_t may_delete_now, delete_now = FALSE;
boolean_t unlinked, toobig = FALSE;
uint64_t txtype;
pathname_t *realnmp = NULL;
pathname_t realnm;
int error;
int zflg = ZEXISTS;
boolean_t waited = B_FALSE;
if (name == NULL)
return (SET_ERROR(EINVAL));
if ((error = zfs_enter_verify_zp(zfsvfs, dzp, FTAG)) != 0)
return (error);
zilog = zfsvfs->z_log;
if (flags & FIGNORECASE) {
zflg |= ZCILOOK;
pn_alloc(&realnm);
realnmp = &realnm;
}
top:
xattr_obj = 0;
xzp = NULL;
/*
* Attempt to lock directory; fail if entry doesn't exist.
*/
if ((error = zfs_dirent_lock(&dl, dzp, name, &zp, zflg,
NULL, realnmp))) {
if (realnmp)
pn_free(realnmp);
zfs_exit(zfsvfs, FTAG);
return (error);
}
if ((error = zfs_zaccess_delete(dzp, zp, cr, zfs_init_idmap))) {
goto out;
}
/*
* Need to use rmdir for removing directories.
*/
if (S_ISDIR(ZTOI(zp)->i_mode)) {
error = SET_ERROR(EPERM);
goto out;
}
mutex_enter(&zp->z_lock);
may_delete_now = atomic_read(&ZTOI(zp)->i_count) == 1 &&
!zn_has_cached_data(zp, 0, LLONG_MAX);
mutex_exit(&zp->z_lock);
/*
* We may delete the znode now, or we may put it in the unlinked set;
* it depends on whether we're the last link, and on whether there are
* other holds on the inode. So we dmu_tx_hold() the right things to
* allow for either case.
*/
obj = zp->z_id;
tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name);
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
zfs_sa_upgrade_txholds(tx, zp);
zfs_sa_upgrade_txholds(tx, dzp);
if (may_delete_now) {
toobig = zp->z_size > zp->z_blksz * zfs_delete_blocks;
/* if the file is too big, only hold_free a token amount */
dmu_tx_hold_free(tx, zp->z_id, 0,
(toobig ? DMU_MAX_ACCESS : DMU_OBJECT_END));
}
/* are there any extended attributes? */
error = sa_lookup(zp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs),
&xattr_obj, sizeof (xattr_obj));
if (error == 0 && xattr_obj) {
error = zfs_zget(zfsvfs, xattr_obj, &xzp);
ASSERT0(error);
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_TRUE);
dmu_tx_hold_sa(tx, xzp->z_sa_hdl, B_FALSE);
}
mutex_enter(&zp->z_lock);
if ((acl_obj = zfs_external_acl(zp)) != 0 && may_delete_now)
dmu_tx_hold_free(tx, acl_obj, 0, DMU_OBJECT_END);
mutex_exit(&zp->z_lock);
/* charge as an update -- would be nice not to charge at all */
dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
/*
* Mark this transaction as typically resulting in a net free of space
*/
dmu_tx_mark_netfree(tx);
error = dmu_tx_assign(tx, (waited ? TXG_NOTHROTTLE : 0) | TXG_NOWAIT);
if (error) {
zfs_dirent_unlock(dl);
if (error == ERESTART) {
waited = B_TRUE;
dmu_tx_wait(tx);
dmu_tx_abort(tx);
zrele(zp);
if (xzp)
zrele(xzp);
goto top;
}
if (realnmp)
pn_free(realnmp);
dmu_tx_abort(tx);
zrele(zp);
if (xzp)
zrele(xzp);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Remove the directory entry.
*/
error = zfs_link_destroy(dl, zp, tx, zflg, &unlinked);
if (error) {
dmu_tx_commit(tx);
goto out;
}
if (unlinked) {
/*
* Hold z_lock so that we can make sure that the ACL obj
* hasn't changed. Could have been deleted due to
* zfs_sa_upgrade().
*/
mutex_enter(&zp->z_lock);
(void) sa_lookup(zp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs),
&xattr_obj_unlinked, sizeof (xattr_obj_unlinked));
delete_now = may_delete_now && !toobig &&
atomic_read(&ZTOI(zp)->i_count) == 1 &&
!zn_has_cached_data(zp, 0, LLONG_MAX) &&
xattr_obj == xattr_obj_unlinked &&
zfs_external_acl(zp) == acl_obj;
VERIFY_IMPLY(xattr_obj_unlinked, xzp);
}
if (delete_now) {
if (xattr_obj_unlinked) {
ASSERT3U(ZTOI(xzp)->i_nlink, ==, 2);
mutex_enter(&xzp->z_lock);
xzp->z_unlinked = B_TRUE;
clear_nlink(ZTOI(xzp));
links = 0;
error = sa_update(xzp->z_sa_hdl, SA_ZPL_LINKS(zfsvfs),
&links, sizeof (links), tx);
ASSERT3U(error, ==, 0);
mutex_exit(&xzp->z_lock);
zfs_unlinked_add(xzp, tx);
if (zp->z_is_sa)
error = sa_remove(zp->z_sa_hdl,
SA_ZPL_XATTR(zfsvfs), tx);
else
error = sa_update(zp->z_sa_hdl,
SA_ZPL_XATTR(zfsvfs), &null_xattr,
sizeof (uint64_t), tx);
ASSERT0(error);
}
/*
* Add to the unlinked set because a new reference could be
* taken concurrently resulting in a deferred destruction.
*/
zfs_unlinked_add(zp, tx);
mutex_exit(&zp->z_lock);
} else if (unlinked) {
mutex_exit(&zp->z_lock);
zfs_unlinked_add(zp, tx);
}
txtype = TX_REMOVE;
if (flags & FIGNORECASE)
txtype |= TX_CI;
zfs_log_remove(zilog, tx, txtype, dzp, name, obj, unlinked);
dmu_tx_commit(tx);
out:
if (realnmp)
pn_free(realnmp);
zfs_dirent_unlock(dl);
zfs_znode_update_vfs(dzp);
zfs_znode_update_vfs(zp);
if (delete_now)
zrele(zp);
else
zfs_zrele_async(zp);
if (xzp) {
zfs_znode_update_vfs(xzp);
zfs_zrele_async(xzp);
}
if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
zil_commit(zilog, 0);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Create a new directory and insert it into dzp using the name
* provided. Return a pointer to the inserted directory.
*
* IN: dzp - znode of directory to add subdir to.
* dirname - name of new directory.
* vap - attributes of new directory.
* cr - credentials of caller.
* flags - case flags.
* vsecp - ACL to be set
* mnt_ns - user namespace of the mount
*
* OUT: zpp - znode of created directory.
*
* RETURN: 0 if success
* error code if failure
*
* Timestamps:
* dzp - ctime|mtime updated
* zpp - ctime|mtime|atime updated
*/
int
zfs_mkdir(znode_t *dzp, char *dirname, vattr_t *vap, znode_t **zpp,
cred_t *cr, int flags, vsecattr_t *vsecp, zidmap_t *mnt_ns)
{
znode_t *zp;
zfsvfs_t *zfsvfs = ZTOZSB(dzp);
zilog_t *zilog;
zfs_dirlock_t *dl;
uint64_t txtype;
dmu_tx_t *tx;
int error;
int zf = ZNEW;
uid_t uid;
gid_t gid = crgetgid(cr);
zfs_acl_ids_t acl_ids;
boolean_t fuid_dirtied;
boolean_t waited = B_FALSE;
ASSERT(S_ISDIR(vap->va_mode));
/*
* If we have an ephemeral id, ACL, or XVATTR then
* make sure file system is at proper version
*/
uid = crgetuid(cr);
if (zfsvfs->z_use_fuids == B_FALSE &&
(vsecp || IS_EPHEMERAL(uid) || IS_EPHEMERAL(gid)))
return (SET_ERROR(EINVAL));
if (dirname == NULL)
return (SET_ERROR(EINVAL));
if ((error = zfs_enter_verify_zp(zfsvfs, dzp, FTAG)) != 0)
return (error);
zilog = zfsvfs->z_log;
if (dzp->z_pflags & ZFS_XATTR) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EINVAL));
}
if (zfsvfs->z_utf8 && u8_validate(dirname,
strlen(dirname), NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EILSEQ));
}
if (flags & FIGNORECASE)
zf |= ZCILOOK;
if (vap->va_mask & ATTR_XVATTR) {
if ((error = secpolicy_xvattr((xvattr_t *)vap,
crgetuid(cr), cr, vap->va_mode)) != 0) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
}
if ((error = zfs_acl_ids_create(dzp, 0, vap, cr,
vsecp, &acl_ids, mnt_ns)) != 0) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* First make sure the new directory doesn't exist.
*
* Existence is checked first to make sure we don't return
* EACCES instead of EEXIST which can cause some applications
* to fail.
*/
top:
*zpp = NULL;
if ((error = zfs_dirent_lock(&dl, dzp, dirname, &zp, zf,
NULL, NULL))) {
zfs_acl_ids_free(&acl_ids);
zfs_exit(zfsvfs, FTAG);
return (error);
}
if ((error = zfs_zaccess(dzp, ACE_ADD_SUBDIRECTORY, 0, B_FALSE, cr,
mnt_ns))) {
zfs_acl_ids_free(&acl_ids);
zfs_dirent_unlock(dl);
zfs_exit(zfsvfs, FTAG);
return (error);
}
if (zfs_acl_ids_overquota(zfsvfs, &acl_ids, zfs_inherit_projid(dzp))) {
zfs_acl_ids_free(&acl_ids);
zfs_dirent_unlock(dl);
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EDQUOT));
}
/*
* Add a new entry to the directory.
*/
tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_zap(tx, dzp->z_id, TRUE, dirname);
dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL);
fuid_dirtied = zfsvfs->z_fuid_dirty;
if (fuid_dirtied)
zfs_fuid_txhold(zfsvfs, tx);
if (!zfsvfs->z_use_sa && acl_ids.z_aclp->z_acl_bytes > ZFS_ACE_SPACE) {
dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0,
acl_ids.z_aclp->z_acl_bytes);
}
dmu_tx_hold_sa_create(tx, acl_ids.z_aclp->z_acl_bytes +
ZFS_SA_BASE_ATTR_SIZE);
error = dmu_tx_assign(tx, (waited ? TXG_NOTHROTTLE : 0) | TXG_NOWAIT);
if (error) {
zfs_dirent_unlock(dl);
if (error == ERESTART) {
waited = B_TRUE;
dmu_tx_wait(tx);
dmu_tx_abort(tx);
goto top;
}
zfs_acl_ids_free(&acl_ids);
dmu_tx_abort(tx);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Create new node.
*/
zfs_mknode(dzp, vap, tx, cr, 0, &zp, &acl_ids);
/*
* Now put new name in parent dir.
*/
error = zfs_link_create(dl, zp, tx, ZNEW);
if (error != 0) {
zfs_znode_delete(zp, tx);
remove_inode_hash(ZTOI(zp));
goto out;
}
if (fuid_dirtied)
zfs_fuid_sync(zfsvfs, tx);
*zpp = zp;
txtype = zfs_log_create_txtype(Z_DIR, vsecp, vap);
if (flags & FIGNORECASE)
txtype |= TX_CI;
zfs_log_create(zilog, tx, txtype, dzp, zp, dirname, vsecp,
acl_ids.z_fuidp, vap);
out:
zfs_acl_ids_free(&acl_ids);
dmu_tx_commit(tx);
zfs_dirent_unlock(dl);
if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
zil_commit(zilog, 0);
if (error != 0) {
zrele(zp);
} else {
zfs_znode_update_vfs(dzp);
zfs_znode_update_vfs(zp);
}
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Remove a directory subdir entry. If the current working
* directory is the same as the subdir to be removed, the
* remove will fail.
*
* IN: dzp - znode of directory to remove from.
* name - name of directory to be removed.
* cwd - inode of current working directory.
* cr - credentials of caller.
* flags - case flags
*
* RETURN: 0 on success, error code on failure.
*
* Timestamps:
* dzp - ctime|mtime updated
*/
int
zfs_rmdir(znode_t *dzp, char *name, znode_t *cwd, cred_t *cr,
int flags)
{
znode_t *zp;
zfsvfs_t *zfsvfs = ZTOZSB(dzp);
zilog_t *zilog;
zfs_dirlock_t *dl;
dmu_tx_t *tx;
int error;
int zflg = ZEXISTS;
boolean_t waited = B_FALSE;
if (name == NULL)
return (SET_ERROR(EINVAL));
if ((error = zfs_enter_verify_zp(zfsvfs, dzp, FTAG)) != 0)
return (error);
zilog = zfsvfs->z_log;
if (flags & FIGNORECASE)
zflg |= ZCILOOK;
top:
zp = NULL;
/*
* Attempt to lock directory; fail if entry doesn't exist.
*/
if ((error = zfs_dirent_lock(&dl, dzp, name, &zp, zflg,
NULL, NULL))) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
if ((error = zfs_zaccess_delete(dzp, zp, cr, zfs_init_idmap))) {
goto out;
}
if (!S_ISDIR(ZTOI(zp)->i_mode)) {
error = SET_ERROR(ENOTDIR);
goto out;
}
if (zp == cwd) {
error = SET_ERROR(EINVAL);
goto out;
}
/*
* Grab a lock on the directory to make sure that no one is
* trying to add (or lookup) entries while we are removing it.
*/
rw_enter(&zp->z_name_lock, RW_WRITER);
/*
* Grab a lock on the parent pointer to make sure we play well
* with the treewalk and directory rename code.
*/
rw_enter(&zp->z_parent_lock, RW_WRITER);
tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name);
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
zfs_sa_upgrade_txholds(tx, zp);
zfs_sa_upgrade_txholds(tx, dzp);
dmu_tx_mark_netfree(tx);
error = dmu_tx_assign(tx, (waited ? TXG_NOTHROTTLE : 0) | TXG_NOWAIT);
if (error) {
rw_exit(&zp->z_parent_lock);
rw_exit(&zp->z_name_lock);
zfs_dirent_unlock(dl);
if (error == ERESTART) {
waited = B_TRUE;
dmu_tx_wait(tx);
dmu_tx_abort(tx);
zrele(zp);
goto top;
}
dmu_tx_abort(tx);
zrele(zp);
zfs_exit(zfsvfs, FTAG);
return (error);
}
error = zfs_link_destroy(dl, zp, tx, zflg, NULL);
if (error == 0) {
uint64_t txtype = TX_RMDIR;
if (flags & FIGNORECASE)
txtype |= TX_CI;
zfs_log_remove(zilog, tx, txtype, dzp, name, ZFS_NO_OBJECT,
B_FALSE);
}
dmu_tx_commit(tx);
rw_exit(&zp->z_parent_lock);
rw_exit(&zp->z_name_lock);
out:
zfs_dirent_unlock(dl);
zfs_znode_update_vfs(dzp);
zfs_znode_update_vfs(zp);
zrele(zp);
if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
zil_commit(zilog, 0);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Read directory entries from the given directory cursor position and emit
* name and position for each entry.
*
* IN: ip - inode of directory to read.
* ctx - directory entry context.
* cr - credentials of caller.
*
* RETURN: 0 if success
* error code if failure
*
* Timestamps:
* ip - atime updated
*
* Note that the low 4 bits of the cookie returned by zap is always zero.
* This allows us to use the low range for "special" directory entries:
* We use 0 for '.', and 1 for '..'. If this is the root of the filesystem,
* we use the offset 2 for the '.zfs' directory.
*/
int
zfs_readdir(struct inode *ip, struct dir_context *ctx, cred_t *cr)
{
(void) cr;
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
objset_t *os;
zap_cursor_t zc;
zap_attribute_t *zap;
int error;
uint8_t prefetch;
uint8_t type;
int done = 0;
uint64_t parent;
uint64_t offset; /* must be unsigned; checks for < 1 */
if ((error = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (error);
if ((error = sa_lookup(zp->z_sa_hdl, SA_ZPL_PARENT(zfsvfs),
&parent, sizeof (parent))) != 0)
goto out;
/*
* Quit if directory has been removed (posix)
*/
if (zp->z_unlinked)
goto out;
error = 0;
os = zfsvfs->z_os;
offset = ctx->pos;
prefetch = zp->z_zn_prefetch;
zap = zap_attribute_alloc();
/*
* Initialize the iterator cursor.
*/
if (offset <= 3) {
/*
* Start iteration from the beginning of the directory.
*/
zap_cursor_init(&zc, os, zp->z_id);
} else {
/*
* The offset is a serialized cursor.
*/
zap_cursor_init_serialized(&zc, os, zp->z_id, offset);
}
/*
* Transform to file-system independent format
*/
while (!done) {
uint64_t objnum;
/*
* Special case `.', `..', and `.zfs'.
*/
if (offset == 0) {
(void) strcpy(zap->za_name, ".");
zap->za_normalization_conflict = 0;
objnum = zp->z_id;
type = DT_DIR;
} else if (offset == 1) {
(void) strcpy(zap->za_name, "..");
zap->za_normalization_conflict = 0;
objnum = parent;
type = DT_DIR;
} else if (offset == 2 && zfs_show_ctldir(zp)) {
(void) strcpy(zap->za_name, ZFS_CTLDIR_NAME);
zap->za_normalization_conflict = 0;
objnum = ZFSCTL_INO_ROOT;
type = DT_DIR;
} else {
/*
* Grab next entry.
*/
if ((error = zap_cursor_retrieve(&zc, zap))) {
if (error == ENOENT)
break;
else
goto update;
}
/*
* Allow multiple entries provided the first entry is
* the object id. Non-zpl consumers may safely make
* use of the additional space.
*
* XXX: This should be a feature flag for compatibility
*/
if (zap->za_integer_length != 8 ||
zap->za_num_integers == 0) {
cmn_err(CE_WARN, "zap_readdir: bad directory "
"entry, obj = %lld, offset = %lld, "
"length = %d, num = %lld\n",
(u_longlong_t)zp->z_id,
(u_longlong_t)offset,
zap->za_integer_length,
(u_longlong_t)zap->za_num_integers);
error = SET_ERROR(ENXIO);
goto update;
}
objnum = ZFS_DIRENT_OBJ(zap->za_first_integer);
type = ZFS_DIRENT_TYPE(zap->za_first_integer);
}
done = !dir_emit(ctx, zap->za_name, strlen(zap->za_name),
objnum, type);
if (done)
break;
if (prefetch)
dmu_prefetch_dnode(os, objnum, ZIO_PRIORITY_SYNC_READ);
/*
* Move to the next entry, fill in the previous offset.
*/
if (offset > 2 || (offset == 2 && !zfs_show_ctldir(zp))) {
zap_cursor_advance(&zc);
offset = zap_cursor_serialize(&zc);
} else {
offset += 1;
}
ctx->pos = offset;
}
zp->z_zn_prefetch = B_FALSE; /* a lookup will re-enable pre-fetching */
update:
zap_cursor_fini(&zc);
zap_attribute_free(zap);
if (error == ENOENT)
error = 0;
out:
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Get the basic file attributes and place them in the provided kstat
* structure. The inode is assumed to be the authoritative source
* for most of the attributes. However, the znode currently has the
* authoritative atime, blksize, and block count.
*
* IN: ip - inode of file.
*
* OUT: sp - kstat values.
*
* RETURN: 0 (always succeeds)
*/
int
#ifdef HAVE_GENERIC_FILLATTR_IDMAP_REQMASK
zfs_getattr_fast(zidmap_t *user_ns, u32 request_mask, struct inode *ip,
struct kstat *sp)
#else
zfs_getattr_fast(zidmap_t *user_ns, struct inode *ip, struct kstat *sp)
#endif
{
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
uint32_t blksize;
u_longlong_t nblocks;
int error;
if ((error = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (error);
mutex_enter(&zp->z_lock);
#ifdef HAVE_GENERIC_FILLATTR_IDMAP_REQMASK
zpl_generic_fillattr(user_ns, request_mask, ip, sp);
#else
zpl_generic_fillattr(user_ns, ip, sp);
#endif
/*
* +1 link count for root inode with visible '.zfs' directory.
*/
if ((zp->z_id == zfsvfs->z_root) && zfs_show_ctldir(zp))
if (sp->nlink < ZFS_LINK_MAX)
sp->nlink++;
sa_object_size(zp->z_sa_hdl, &blksize, &nblocks);
sp->blksize = blksize;
sp->blocks = nblocks;
if (unlikely(zp->z_blksz == 0)) {
/*
* Block size hasn't been set; suggest maximal I/O transfers.
*/
sp->blksize = zfsvfs->z_max_blksz;
}
mutex_exit(&zp->z_lock);
/*
* Required to prevent NFS client from detecting different inode
* numbers of snapshot root dentry before and after snapshot mount.
*/
if (zfsvfs->z_issnap) {
if (ip->i_sb->s_root->d_inode == ip)
sp->ino = ZFSCTL_INO_SNAPDIRS -
dmu_objset_id(zfsvfs->z_os);
}
zfs_exit(zfsvfs, FTAG);
return (0);
}
/*
* For the operation of changing file's user/group/project, we need to
* handle not only the main object that is assigned to the file directly,
* but also the ones that are used by the file via hidden xattr directory.
*
* Because the xattr directory may contains many EA entries, as to it may
* be impossible to change all of them via the transaction of changing the
* main object's user/group/project attributes. Then we have to change them
* via other multiple independent transactions one by one. It may be not good
* solution, but we have no better idea yet.
*/
static int
zfs_setattr_dir(znode_t *dzp)
{
struct inode *dxip = ZTOI(dzp);
struct inode *xip = NULL;
zfsvfs_t *zfsvfs = ZTOZSB(dzp);
objset_t *os = zfsvfs->z_os;
zap_cursor_t zc;
zap_attribute_t *zap;
zfs_dirlock_t *dl;
znode_t *zp = NULL;
dmu_tx_t *tx = NULL;
uint64_t uid, gid;
sa_bulk_attr_t bulk[4];
int count;
int err;
zap = zap_attribute_alloc();
zap_cursor_init(&zc, os, dzp->z_id);
while ((err = zap_cursor_retrieve(&zc, zap)) == 0) {
count = 0;
if (zap->za_integer_length != 8 || zap->za_num_integers != 1) {
err = ENXIO;
break;
}
err = zfs_dirent_lock(&dl, dzp, (char *)zap->za_name, &zp,
ZEXISTS, NULL, NULL);
if (err == ENOENT)
goto next;
if (err)
break;
xip = ZTOI(zp);
if (KUID_TO_SUID(xip->i_uid) == KUID_TO_SUID(dxip->i_uid) &&
KGID_TO_SGID(xip->i_gid) == KGID_TO_SGID(dxip->i_gid) &&
zp->z_projid == dzp->z_projid)
goto next;
tx = dmu_tx_create(os);
if (!(zp->z_pflags & ZFS_PROJID))
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_TRUE);
else
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
err = dmu_tx_assign(tx, TXG_WAIT);
if (err)
break;
mutex_enter(&dzp->z_lock);
if (KUID_TO_SUID(xip->i_uid) != KUID_TO_SUID(dxip->i_uid)) {
xip->i_uid = dxip->i_uid;
uid = zfs_uid_read(dxip);
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_UID(zfsvfs), NULL,
&uid, sizeof (uid));
}
if (KGID_TO_SGID(xip->i_gid) != KGID_TO_SGID(dxip->i_gid)) {
xip->i_gid = dxip->i_gid;
gid = zfs_gid_read(dxip);
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GID(zfsvfs), NULL,
&gid, sizeof (gid));
}
uint64_t projid = dzp->z_projid;
if (zp->z_projid != projid) {
if (!(zp->z_pflags & ZFS_PROJID)) {
err = sa_add_projid(zp->z_sa_hdl, tx, projid);
if (unlikely(err == EEXIST)) {
err = 0;
} else if (err != 0) {
goto sa_add_projid_err;
} else {
projid = ZFS_INVALID_PROJID;
}
}
if (projid != ZFS_INVALID_PROJID) {
zp->z_projid = projid;
SA_ADD_BULK_ATTR(bulk, count,
SA_ZPL_PROJID(zfsvfs), NULL, &zp->z_projid,
sizeof (zp->z_projid));
}
}
sa_add_projid_err:
mutex_exit(&dzp->z_lock);
if (likely(count > 0)) {
err = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx);
dmu_tx_commit(tx);
} else if (projid == ZFS_INVALID_PROJID) {
dmu_tx_commit(tx);
} else {
dmu_tx_abort(tx);
}
tx = NULL;
if (err != 0 && err != ENOENT)
break;
next:
if (zp) {
zrele(zp);
zp = NULL;
zfs_dirent_unlock(dl);
}
zap_cursor_advance(&zc);
}
if (tx)
dmu_tx_abort(tx);
if (zp) {
zrele(zp);
zfs_dirent_unlock(dl);
}
zap_cursor_fini(&zc);
zap_attribute_free(zap);
return (err == ENOENT ? 0 : err);
}
/*
* Set the file attributes to the values contained in the
* vattr structure.
*
* IN: zp - znode of file to be modified.
* vap - new attribute values.
* If ATTR_XVATTR set, then optional attrs are being set
* flags - ATTR_UTIME set if non-default time values provided.
* - ATTR_NOACLCHECK (CIFS context only).
* cr - credentials of caller.
* mnt_ns - user namespace of the mount
*
* RETURN: 0 if success
* error code if failure
*
* Timestamps:
* ip - ctime updated, mtime updated if size changed.
*/
int
zfs_setattr(znode_t *zp, vattr_t *vap, int flags, cred_t *cr, zidmap_t *mnt_ns)
{
struct inode *ip;
zfsvfs_t *zfsvfs = ZTOZSB(zp);
objset_t *os;
zilog_t *zilog;
dmu_tx_t *tx;
vattr_t oldva;
xvattr_t *tmpxvattr;
uint_t mask = vap->va_mask;
uint_t saved_mask = 0;
int trim_mask = 0;
uint64_t new_mode;
uint64_t new_kuid = 0, new_kgid = 0, new_uid, new_gid;
uint64_t xattr_obj;
uint64_t mtime[2], ctime[2], atime[2];
uint64_t projid = ZFS_INVALID_PROJID;
znode_t *attrzp;
int need_policy = FALSE;
int err, err2 = 0;
zfs_fuid_info_t *fuidp = NULL;
xvattr_t *xvap = (xvattr_t *)vap; /* vap may be an xvattr_t * */
xoptattr_t *xoap;
zfs_acl_t *aclp;
boolean_t skipaclchk = (flags & ATTR_NOACLCHECK) ? B_TRUE : B_FALSE;
boolean_t fuid_dirtied = B_FALSE;
boolean_t handle_eadir = B_FALSE;
sa_bulk_attr_t *bulk, *xattr_bulk;
int count = 0, xattr_count = 0, bulks = 8;
if (mask == 0)
return (0);
if ((err = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (err);
ip = ZTOI(zp);
os = zfsvfs->z_os;
/*
* If this is a xvattr_t, then get a pointer to the structure of
* optional attributes. If this is NULL, then we have a vattr_t.
*/
xoap = xva_getxoptattr(xvap);
if (xoap != NULL && (mask & ATTR_XVATTR)) {
if (XVA_ISSET_REQ(xvap, XAT_PROJID)) {
if (!dmu_objset_projectquota_enabled(os) ||
(!S_ISREG(ip->i_mode) && !S_ISDIR(ip->i_mode))) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(ENOTSUP));
}
projid = xoap->xoa_projid;
if (unlikely(projid == ZFS_INVALID_PROJID)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EINVAL));
}
if (projid == zp->z_projid && zp->z_pflags & ZFS_PROJID)
projid = ZFS_INVALID_PROJID;
else
need_policy = TRUE;
}
if (XVA_ISSET_REQ(xvap, XAT_PROJINHERIT) &&
(xoap->xoa_projinherit !=
((zp->z_pflags & ZFS_PROJINHERIT) != 0)) &&
(!dmu_objset_projectquota_enabled(os) ||
(!S_ISREG(ip->i_mode) && !S_ISDIR(ip->i_mode)))) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(ENOTSUP));
}
}
zilog = zfsvfs->z_log;
/*
* Make sure that if we have ephemeral uid/gid or xvattr specified
* that file system is at proper version level
*/
if (zfsvfs->z_use_fuids == B_FALSE &&
(((mask & ATTR_UID) && IS_EPHEMERAL(vap->va_uid)) ||
((mask & ATTR_GID) && IS_EPHEMERAL(vap->va_gid)) ||
(mask & ATTR_XVATTR))) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EINVAL));
}
if (mask & ATTR_SIZE && S_ISDIR(ip->i_mode)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EISDIR));
}
if (mask & ATTR_SIZE && !S_ISREG(ip->i_mode) && !S_ISFIFO(ip->i_mode)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EINVAL));
}
tmpxvattr = kmem_alloc(sizeof (xvattr_t), KM_SLEEP);
xva_init(tmpxvattr);
bulk = kmem_alloc(sizeof (sa_bulk_attr_t) * bulks, KM_SLEEP);
xattr_bulk = kmem_alloc(sizeof (sa_bulk_attr_t) * bulks, KM_SLEEP);
/*
* Immutable files can only alter immutable bit and atime
*/
if ((zp->z_pflags & ZFS_IMMUTABLE) &&
((mask & (ATTR_SIZE|ATTR_UID|ATTR_GID|ATTR_MTIME|ATTR_MODE)) ||
((mask & ATTR_XVATTR) && XVA_ISSET_REQ(xvap, XAT_CREATETIME)))) {
err = SET_ERROR(EPERM);
goto out3;
}
if ((mask & ATTR_SIZE) && (zp->z_pflags & ZFS_READONLY)) {
err = SET_ERROR(EPERM);
goto out3;
}
/*
* Verify timestamps doesn't overflow 32 bits.
* ZFS can handle large timestamps, but 32bit syscalls can't
* handle times greater than 2039. This check should be removed
* once large timestamps are fully supported.
*/
if (mask & (ATTR_ATIME | ATTR_MTIME)) {
if (((mask & ATTR_ATIME) &&
TIMESPEC_OVERFLOW(&vap->va_atime)) ||
((mask & ATTR_MTIME) &&
TIMESPEC_OVERFLOW(&vap->va_mtime))) {
err = SET_ERROR(EOVERFLOW);
goto out3;
}
}
top:
attrzp = NULL;
aclp = NULL;
/* Can this be moved to before the top label? */
if (zfs_is_readonly(zfsvfs)) {
err = SET_ERROR(EROFS);
goto out3;
}
/*
* First validate permissions
*/
if (mask & ATTR_SIZE) {
err = zfs_zaccess(zp, ACE_WRITE_DATA, 0, skipaclchk, cr,
mnt_ns);
if (err)
goto out3;
/*
* XXX - Note, we are not providing any open
* mode flags here (like FNDELAY), so we may
* block if there are locks present... this
* should be addressed in openat().
*/
/* XXX - would it be OK to generate a log record here? */
err = zfs_freesp(zp, vap->va_size, 0, 0, FALSE);
if (err)
goto out3;
}
if (mask & (ATTR_ATIME|ATTR_MTIME) ||
((mask & ATTR_XVATTR) && (XVA_ISSET_REQ(xvap, XAT_HIDDEN) ||
XVA_ISSET_REQ(xvap, XAT_READONLY) ||
XVA_ISSET_REQ(xvap, XAT_ARCHIVE) ||
XVA_ISSET_REQ(xvap, XAT_OFFLINE) ||
XVA_ISSET_REQ(xvap, XAT_SPARSE) ||
XVA_ISSET_REQ(xvap, XAT_CREATETIME) ||
XVA_ISSET_REQ(xvap, XAT_SYSTEM)))) {
need_policy = zfs_zaccess(zp, ACE_WRITE_ATTRIBUTES, 0,
skipaclchk, cr, mnt_ns);
}
if (mask & (ATTR_UID|ATTR_GID)) {
int idmask = (mask & (ATTR_UID|ATTR_GID));
int take_owner;
int take_group;
uid_t uid;
gid_t gid;
/*
* NOTE: even if a new mode is being set,
* we may clear S_ISUID/S_ISGID bits.
*/
if (!(mask & ATTR_MODE))
vap->va_mode = zp->z_mode;
/*
* Take ownership or chgrp to group we are a member of
*/
uid = zfs_uid_to_vfsuid(mnt_ns, zfs_i_user_ns(ip),
vap->va_uid);
gid = zfs_gid_to_vfsgid(mnt_ns, zfs_i_user_ns(ip),
vap->va_gid);
take_owner = (mask & ATTR_UID) && (uid == crgetuid(cr));
take_group = (mask & ATTR_GID) &&
zfs_groupmember(zfsvfs, gid, cr);
/*
* If both ATTR_UID and ATTR_GID are set then take_owner and
* take_group must both be set in order to allow taking
* ownership.
*
* Otherwise, send the check through secpolicy_vnode_setattr()
*
*/
if (((idmask == (ATTR_UID|ATTR_GID)) &&
take_owner && take_group) ||
((idmask == ATTR_UID) && take_owner) ||
((idmask == ATTR_GID) && take_group)) {
if (zfs_zaccess(zp, ACE_WRITE_OWNER, 0,
skipaclchk, cr, mnt_ns) == 0) {
/*
* Remove setuid/setgid for non-privileged users
*/
(void) secpolicy_setid_clear(vap, cr);
trim_mask = (mask & (ATTR_UID|ATTR_GID));
} else {
need_policy = TRUE;
}
} else {
need_policy = TRUE;
}
}
mutex_enter(&zp->z_lock);
oldva.va_mode = zp->z_mode;
zfs_fuid_map_ids(zp, cr, &oldva.va_uid, &oldva.va_gid);
if (mask & ATTR_XVATTR) {
/*
* Update xvattr mask to include only those attributes
* that are actually changing.
*
* the bits will be restored prior to actually setting
* the attributes so the caller thinks they were set.
*/
if (XVA_ISSET_REQ(xvap, XAT_APPENDONLY)) {
if (xoap->xoa_appendonly !=
((zp->z_pflags & ZFS_APPENDONLY) != 0)) {
need_policy = TRUE;
} else {
XVA_CLR_REQ(xvap, XAT_APPENDONLY);
XVA_SET_REQ(tmpxvattr, XAT_APPENDONLY);
}
}
if (XVA_ISSET_REQ(xvap, XAT_PROJINHERIT)) {
if (xoap->xoa_projinherit !=
((zp->z_pflags & ZFS_PROJINHERIT) != 0)) {
need_policy = TRUE;
} else {
XVA_CLR_REQ(xvap, XAT_PROJINHERIT);
XVA_SET_REQ(tmpxvattr, XAT_PROJINHERIT);
}
}
if (XVA_ISSET_REQ(xvap, XAT_NOUNLINK)) {
if (xoap->xoa_nounlink !=
((zp->z_pflags & ZFS_NOUNLINK) != 0)) {
need_policy = TRUE;
} else {
XVA_CLR_REQ(xvap, XAT_NOUNLINK);
XVA_SET_REQ(tmpxvattr, XAT_NOUNLINK);
}
}
if (XVA_ISSET_REQ(xvap, XAT_IMMUTABLE)) {
if (xoap->xoa_immutable !=
((zp->z_pflags & ZFS_IMMUTABLE) != 0)) {
need_policy = TRUE;
} else {
XVA_CLR_REQ(xvap, XAT_IMMUTABLE);
XVA_SET_REQ(tmpxvattr, XAT_IMMUTABLE);
}
}
if (XVA_ISSET_REQ(xvap, XAT_NODUMP)) {
if (xoap->xoa_nodump !=
((zp->z_pflags & ZFS_NODUMP) != 0)) {
need_policy = TRUE;
} else {
XVA_CLR_REQ(xvap, XAT_NODUMP);
XVA_SET_REQ(tmpxvattr, XAT_NODUMP);
}
}
if (XVA_ISSET_REQ(xvap, XAT_AV_MODIFIED)) {
if (xoap->xoa_av_modified !=
((zp->z_pflags & ZFS_AV_MODIFIED) != 0)) {
need_policy = TRUE;
} else {
XVA_CLR_REQ(xvap, XAT_AV_MODIFIED);
XVA_SET_REQ(tmpxvattr, XAT_AV_MODIFIED);
}
}
if (XVA_ISSET_REQ(xvap, XAT_AV_QUARANTINED)) {
if ((!S_ISREG(ip->i_mode) &&
xoap->xoa_av_quarantined) ||
xoap->xoa_av_quarantined !=
((zp->z_pflags & ZFS_AV_QUARANTINED) != 0)) {
need_policy = TRUE;
} else {
XVA_CLR_REQ(xvap, XAT_AV_QUARANTINED);
XVA_SET_REQ(tmpxvattr, XAT_AV_QUARANTINED);
}
}
if (XVA_ISSET_REQ(xvap, XAT_REPARSE)) {
mutex_exit(&zp->z_lock);
err = SET_ERROR(EPERM);
goto out3;
}
if (need_policy == FALSE &&
(XVA_ISSET_REQ(xvap, XAT_AV_SCANSTAMP) ||
XVA_ISSET_REQ(xvap, XAT_OPAQUE))) {
need_policy = TRUE;
}
}
mutex_exit(&zp->z_lock);
if (mask & ATTR_MODE) {
if (zfs_zaccess(zp, ACE_WRITE_ACL, 0, skipaclchk, cr,
mnt_ns) == 0) {
err = secpolicy_setid_setsticky_clear(ip, vap,
&oldva, cr, mnt_ns, zfs_i_user_ns(ip));
if (err)
goto out3;
trim_mask |= ATTR_MODE;
} else {
need_policy = TRUE;
}
}
if (need_policy) {
/*
* If trim_mask is set then take ownership
* has been granted or write_acl is present and user
* has the ability to modify mode. In that case remove
* UID|GID and or MODE from mask so that
* secpolicy_vnode_setattr() doesn't revoke it.
*/
if (trim_mask) {
saved_mask = vap->va_mask;
vap->va_mask &= ~trim_mask;
}
err = secpolicy_vnode_setattr(cr, ip, vap, &oldva, flags,
zfs_zaccess_unix, zp);
if (err)
goto out3;
if (trim_mask)
vap->va_mask |= saved_mask;
}
/*
* secpolicy_vnode_setattr, or take ownership may have
* changed va_mask
*/
mask = vap->va_mask;
if ((mask & (ATTR_UID | ATTR_GID)) || projid != ZFS_INVALID_PROJID) {
handle_eadir = B_TRUE;
err = sa_lookup(zp->z_sa_hdl, SA_ZPL_XATTR(zfsvfs),
&xattr_obj, sizeof (xattr_obj));
if (err == 0 && xattr_obj) {
err = zfs_zget(ZTOZSB(zp), xattr_obj, &attrzp);
if (err)
goto out2;
}
if (mask & ATTR_UID) {
new_kuid = zfs_fuid_create(zfsvfs,
(uint64_t)vap->va_uid, cr, ZFS_OWNER, &fuidp);
if (new_kuid != KUID_TO_SUID(ZTOI(zp)->i_uid) &&
zfs_id_overquota(zfsvfs, DMU_USERUSED_OBJECT,
new_kuid)) {
if (attrzp)
zrele(attrzp);
err = SET_ERROR(EDQUOT);
goto out2;
}
}
if (mask & ATTR_GID) {
new_kgid = zfs_fuid_create(zfsvfs,
(uint64_t)vap->va_gid, cr, ZFS_GROUP, &fuidp);
if (new_kgid != KGID_TO_SGID(ZTOI(zp)->i_gid) &&
zfs_id_overquota(zfsvfs, DMU_GROUPUSED_OBJECT,
new_kgid)) {
if (attrzp)
zrele(attrzp);
err = SET_ERROR(EDQUOT);
goto out2;
}
}
if (projid != ZFS_INVALID_PROJID &&
zfs_id_overquota(zfsvfs, DMU_PROJECTUSED_OBJECT, projid)) {
if (attrzp)
zrele(attrzp);
err = EDQUOT;
goto out2;
}
}
tx = dmu_tx_create(os);
if (mask & ATTR_MODE) {
uint64_t pmode = zp->z_mode;
uint64_t acl_obj;
new_mode = (pmode & S_IFMT) | (vap->va_mode & ~S_IFMT);
if (ZTOZSB(zp)->z_acl_mode == ZFS_ACL_RESTRICTED &&
!(zp->z_pflags & ZFS_ACL_TRIVIAL)) {
err = EPERM;
goto out;
}
if ((err = zfs_acl_chmod_setattr(zp, &aclp, new_mode)))
goto out;
mutex_enter(&zp->z_lock);
if (!zp->z_is_sa && ((acl_obj = zfs_external_acl(zp)) != 0)) {
/*
* Are we upgrading ACL from old V0 format
* to V1 format?
*/
if (zfsvfs->z_version >= ZPL_VERSION_FUID &&
zfs_znode_acl_version(zp) ==
ZFS_ACL_VERSION_INITIAL) {
dmu_tx_hold_free(tx, acl_obj, 0,
DMU_OBJECT_END);
dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
0, aclp->z_acl_bytes);
} else {
dmu_tx_hold_write(tx, acl_obj, 0,
aclp->z_acl_bytes);
}
} else if (!zp->z_is_sa && aclp->z_acl_bytes > ZFS_ACE_SPACE) {
dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
0, aclp->z_acl_bytes);
}
mutex_exit(&zp->z_lock);
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_TRUE);
} else {
if (((mask & ATTR_XVATTR) &&
XVA_ISSET_REQ(xvap, XAT_AV_SCANSTAMP)) ||
(projid != ZFS_INVALID_PROJID &&
!(zp->z_pflags & ZFS_PROJID)))
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_TRUE);
else
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
}
if (attrzp) {
dmu_tx_hold_sa(tx, attrzp->z_sa_hdl, B_FALSE);
}
fuid_dirtied = zfsvfs->z_fuid_dirty;
if (fuid_dirtied)
zfs_fuid_txhold(zfsvfs, tx);
zfs_sa_upgrade_txholds(tx, zp);
err = dmu_tx_assign(tx, TXG_WAIT);
if (err)
goto out;
count = 0;
/*
* Set each attribute requested.
* We group settings according to the locks they need to acquire.
*
* Note: you cannot set ctime directly, although it will be
* updated as a side-effect of calling this function.
*/
if (projid != ZFS_INVALID_PROJID && !(zp->z_pflags & ZFS_PROJID)) {
/*
* For the existed object that is upgraded from old system,
* its on-disk layout has no slot for the project ID attribute.
* But quota accounting logic needs to access related slots by
* offset directly. So we need to adjust old objects' layout
* to make the project ID to some unified and fixed offset.
*/
if (attrzp)
err = sa_add_projid(attrzp->z_sa_hdl, tx, projid);
if (err == 0)
err = sa_add_projid(zp->z_sa_hdl, tx, projid);
if (unlikely(err == EEXIST))
err = 0;
else if (err != 0)
goto out;
else
projid = ZFS_INVALID_PROJID;
}
if (mask & (ATTR_UID|ATTR_GID|ATTR_MODE))
mutex_enter(&zp->z_acl_lock);
mutex_enter(&zp->z_lock);
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_FLAGS(zfsvfs), NULL,
&zp->z_pflags, sizeof (zp->z_pflags));
if (attrzp) {
if (mask & (ATTR_UID|ATTR_GID|ATTR_MODE))
mutex_enter(&attrzp->z_acl_lock);
mutex_enter(&attrzp->z_lock);
SA_ADD_BULK_ATTR(xattr_bulk, xattr_count,
SA_ZPL_FLAGS(zfsvfs), NULL, &attrzp->z_pflags,
sizeof (attrzp->z_pflags));
if (projid != ZFS_INVALID_PROJID) {
attrzp->z_projid = projid;
SA_ADD_BULK_ATTR(xattr_bulk, xattr_count,
SA_ZPL_PROJID(zfsvfs), NULL, &attrzp->z_projid,
sizeof (attrzp->z_projid));
}
}
if (mask & (ATTR_UID|ATTR_GID)) {
if (mask & ATTR_UID) {
ZTOI(zp)->i_uid = SUID_TO_KUID(new_kuid);
new_uid = zfs_uid_read(ZTOI(zp));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_UID(zfsvfs), NULL,
&new_uid, sizeof (new_uid));
if (attrzp) {
SA_ADD_BULK_ATTR(xattr_bulk, xattr_count,
SA_ZPL_UID(zfsvfs), NULL, &new_uid,
sizeof (new_uid));
ZTOI(attrzp)->i_uid = SUID_TO_KUID(new_uid);
}
}
if (mask & ATTR_GID) {
ZTOI(zp)->i_gid = SGID_TO_KGID(new_kgid);
new_gid = zfs_gid_read(ZTOI(zp));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GID(zfsvfs),
NULL, &new_gid, sizeof (new_gid));
if (attrzp) {
SA_ADD_BULK_ATTR(xattr_bulk, xattr_count,
SA_ZPL_GID(zfsvfs), NULL, &new_gid,
sizeof (new_gid));
ZTOI(attrzp)->i_gid = SGID_TO_KGID(new_kgid);
}
}
if (!(mask & ATTR_MODE)) {
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MODE(zfsvfs),
NULL, &new_mode, sizeof (new_mode));
new_mode = zp->z_mode;
}
err = zfs_acl_chown_setattr(zp);
ASSERT(err == 0);
if (attrzp) {
err = zfs_acl_chown_setattr(attrzp);
ASSERT(err == 0);
}
}
if (mask & ATTR_MODE) {
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MODE(zfsvfs), NULL,
&new_mode, sizeof (new_mode));
zp->z_mode = ZTOI(zp)->i_mode = new_mode;
ASSERT3P(aclp, !=, NULL);
err = zfs_aclset_common(zp, aclp, cr, tx);
ASSERT0(err);
if (zp->z_acl_cached)
zfs_acl_free(zp->z_acl_cached);
zp->z_acl_cached = aclp;
aclp = NULL;
}
if ((mask & ATTR_ATIME) || zp->z_atime_dirty) {
zp->z_atime_dirty = B_FALSE;
inode_timespec_t tmp_atime = zpl_inode_get_atime(ip);
ZFS_TIME_ENCODE(&tmp_atime, atime);
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_ATIME(zfsvfs), NULL,
&atime, sizeof (atime));
}
if (mask & (ATTR_MTIME | ATTR_SIZE)) {
ZFS_TIME_ENCODE(&vap->va_mtime, mtime);
zpl_inode_set_mtime_to_ts(ZTOI(zp),
zpl_inode_timestamp_truncate(vap->va_mtime, ZTOI(zp)));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL,
mtime, sizeof (mtime));
}
if (mask & (ATTR_CTIME | ATTR_SIZE)) {
ZFS_TIME_ENCODE(&vap->va_ctime, ctime);
zpl_inode_set_ctime_to_ts(ZTOI(zp),
zpl_inode_timestamp_truncate(vap->va_ctime, ZTOI(zp)));
SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL,
ctime, sizeof (ctime));
}
if (projid != ZFS_INVALID_PROJID) {
zp->z_projid = projid;
SA_ADD_BULK_ATTR(bulk, count,
SA_ZPL_PROJID(zfsvfs), NULL, &zp->z_projid,
sizeof (zp->z_projid));
}
if (attrzp && mask) {
SA_ADD_BULK_ATTR(xattr_bulk, xattr_count,
SA_ZPL_CTIME(zfsvfs), NULL, &ctime,
sizeof (ctime));
}
/*
* Do this after setting timestamps to prevent timestamp
* update from toggling bit
*/
if (xoap && (mask & ATTR_XVATTR)) {
/*
* restore trimmed off masks
* so that return masks can be set for caller.
*/
if (XVA_ISSET_REQ(tmpxvattr, XAT_APPENDONLY)) {
XVA_SET_REQ(xvap, XAT_APPENDONLY);
}
if (XVA_ISSET_REQ(tmpxvattr, XAT_NOUNLINK)) {
XVA_SET_REQ(xvap, XAT_NOUNLINK);
}
if (XVA_ISSET_REQ(tmpxvattr, XAT_IMMUTABLE)) {
XVA_SET_REQ(xvap, XAT_IMMUTABLE);
}
if (XVA_ISSET_REQ(tmpxvattr, XAT_NODUMP)) {
XVA_SET_REQ(xvap, XAT_NODUMP);
}
if (XVA_ISSET_REQ(tmpxvattr, XAT_AV_MODIFIED)) {
XVA_SET_REQ(xvap, XAT_AV_MODIFIED);
}
if (XVA_ISSET_REQ(tmpxvattr, XAT_AV_QUARANTINED)) {
XVA_SET_REQ(xvap, XAT_AV_QUARANTINED);
}
if (XVA_ISSET_REQ(tmpxvattr, XAT_PROJINHERIT)) {
XVA_SET_REQ(xvap, XAT_PROJINHERIT);
}
if (XVA_ISSET_REQ(xvap, XAT_AV_SCANSTAMP))
ASSERT(S_ISREG(ip->i_mode));
zfs_xvattr_set(zp, xvap, tx);
}
if (fuid_dirtied)
zfs_fuid_sync(zfsvfs, tx);
if (mask != 0)
zfs_log_setattr(zilog, tx, TX_SETATTR, zp, vap, mask, fuidp);
mutex_exit(&zp->z_lock);
if (mask & (ATTR_UID|ATTR_GID|ATTR_MODE))
mutex_exit(&zp->z_acl_lock);
if (attrzp) {
if (mask & (ATTR_UID|ATTR_GID|ATTR_MODE))
mutex_exit(&attrzp->z_acl_lock);
mutex_exit(&attrzp->z_lock);
}
out:
if (err == 0 && xattr_count > 0) {
err2 = sa_bulk_update(attrzp->z_sa_hdl, xattr_bulk,
xattr_count, tx);
ASSERT(err2 == 0);
}
if (aclp)
zfs_acl_free(aclp);
if (fuidp) {
zfs_fuid_info_free(fuidp);
fuidp = NULL;
}
if (err) {
dmu_tx_abort(tx);
if (attrzp)
zrele(attrzp);
if (err == ERESTART)
goto top;
} else {
if (count > 0)
err2 = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx);
dmu_tx_commit(tx);
if (attrzp) {
if (err2 == 0 && handle_eadir)
err = zfs_setattr_dir(attrzp);
zrele(attrzp);
}
zfs_znode_update_vfs(zp);
}
out2:
if (os->os_sync == ZFS_SYNC_ALWAYS)
zil_commit(zilog, 0);
out3:
kmem_free(xattr_bulk, sizeof (sa_bulk_attr_t) * bulks);
kmem_free(bulk, sizeof (sa_bulk_attr_t) * bulks);
kmem_free(tmpxvattr, sizeof (xvattr_t));
zfs_exit(zfsvfs, FTAG);
return (err);
}
typedef struct zfs_zlock {
krwlock_t *zl_rwlock; /* lock we acquired */
znode_t *zl_znode; /* znode we held */
struct zfs_zlock *zl_next; /* next in list */
} zfs_zlock_t;
/*
* Drop locks and release vnodes that were held by zfs_rename_lock().
*/
static void
zfs_rename_unlock(zfs_zlock_t **zlpp)
{
zfs_zlock_t *zl;
while ((zl = *zlpp) != NULL) {
if (zl->zl_znode != NULL)
zfs_zrele_async(zl->zl_znode);
rw_exit(zl->zl_rwlock);
*zlpp = zl->zl_next;
kmem_free(zl, sizeof (*zl));
}
}
/*
* Search back through the directory tree, using the ".." entries.
* Lock each directory in the chain to prevent concurrent renames.
* Fail any attempt to move a directory into one of its own descendants.
* XXX - z_parent_lock can overlap with map or grow locks
*/
static int
zfs_rename_lock(znode_t *szp, znode_t *tdzp, znode_t *sdzp, zfs_zlock_t **zlpp)
{
zfs_zlock_t *zl;
znode_t *zp = tdzp;
uint64_t rootid = ZTOZSB(zp)->z_root;
uint64_t oidp = zp->z_id;
krwlock_t *rwlp = &szp->z_parent_lock;
krw_t rw = RW_WRITER;
/*
* First pass write-locks szp and compares to zp->z_id.
* Later passes read-lock zp and compare to zp->z_parent.
*/
do {
if (!rw_tryenter(rwlp, rw)) {
/*
* Another thread is renaming in this path.
* Note that if we are a WRITER, we don't have any
* parent_locks held yet.
*/
if (rw == RW_READER && zp->z_id > szp->z_id) {
/*
* Drop our locks and restart
*/
zfs_rename_unlock(&zl);
*zlpp = NULL;
zp = tdzp;
oidp = zp->z_id;
rwlp = &szp->z_parent_lock;
rw = RW_WRITER;
continue;
} else {
/*
* Wait for other thread to drop its locks
*/
rw_enter(rwlp, rw);
}
}
zl = kmem_alloc(sizeof (*zl), KM_SLEEP);
zl->zl_rwlock = rwlp;
zl->zl_znode = NULL;
zl->zl_next = *zlpp;
*zlpp = zl;
if (oidp == szp->z_id) /* We're a descendant of szp */
return (SET_ERROR(EINVAL));
if (oidp == rootid) /* We've hit the top */
return (0);
if (rw == RW_READER) { /* i.e. not the first pass */
int error = zfs_zget(ZTOZSB(zp), oidp, &zp);
if (error)
return (error);
zl->zl_znode = zp;
}
(void) sa_lookup(zp->z_sa_hdl, SA_ZPL_PARENT(ZTOZSB(zp)),
&oidp, sizeof (oidp));
rwlp = &zp->z_parent_lock;
rw = RW_READER;
} while (zp->z_id != sdzp->z_id);
return (0);
}
/*
* Move an entry from the provided source directory to the target
* directory. Change the entry name as indicated.
*
* IN: sdzp - Source directory containing the "old entry".
* snm - Old entry name.
* tdzp - Target directory to contain the "new entry".
* tnm - New entry name.
* cr - credentials of caller.
* flags - case flags
* rflags - RENAME_* flags
* wa_vap - attributes for RENAME_WHITEOUT (must be a char 0:0).
* mnt_ns - user namespace of the mount
*
* RETURN: 0 on success, error code on failure.
*
* Timestamps:
* sdzp,tdzp - ctime|mtime updated
*/
int
zfs_rename(znode_t *sdzp, char *snm, znode_t *tdzp, char *tnm,
cred_t *cr, int flags, uint64_t rflags, vattr_t *wo_vap, zidmap_t *mnt_ns)
{
znode_t *szp, *tzp;
zfsvfs_t *zfsvfs = ZTOZSB(sdzp);
zilog_t *zilog;
zfs_dirlock_t *sdl, *tdl;
dmu_tx_t *tx;
zfs_zlock_t *zl;
int cmp, serr, terr;
int error = 0;
int zflg = 0;
boolean_t waited = B_FALSE;
/* Needed for whiteout inode creation. */
boolean_t fuid_dirtied;
zfs_acl_ids_t acl_ids;
boolean_t have_acl = B_FALSE;
znode_t *wzp = NULL;
if (snm == NULL || tnm == NULL)
return (SET_ERROR(EINVAL));
if (rflags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
return (SET_ERROR(EINVAL));
/* Already checked by Linux VFS, but just to make sure. */
if (rflags & RENAME_EXCHANGE &&
(rflags & (RENAME_NOREPLACE | RENAME_WHITEOUT)))
return (SET_ERROR(EINVAL));
/*
* Make sure we only get wo_vap iff. RENAME_WHITEOUT and that it's the
* right kind of vattr_t for the whiteout file. These are set
* internally by ZFS so should never be incorrect.
*/
VERIFY_EQUIV(rflags & RENAME_WHITEOUT, wo_vap != NULL);
VERIFY_IMPLY(wo_vap, wo_vap->va_mode == S_IFCHR);
VERIFY_IMPLY(wo_vap, wo_vap->va_rdev == makedevice(0, 0));
if ((error = zfs_enter_verify_zp(zfsvfs, sdzp, FTAG)) != 0)
return (error);
zilog = zfsvfs->z_log;
if ((error = zfs_verify_zp(tdzp)) != 0) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* We check i_sb because snapshots and the ctldir must have different
* super blocks.
*/
if (ZTOI(tdzp)->i_sb != ZTOI(sdzp)->i_sb ||
zfsctl_is_node(ZTOI(tdzp))) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EXDEV));
}
if (zfsvfs->z_utf8 && u8_validate(tnm,
strlen(tnm), NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EILSEQ));
}
if (flags & FIGNORECASE)
zflg |= ZCILOOK;
top:
szp = NULL;
tzp = NULL;
zl = NULL;
/*
* This is to prevent the creation of links into attribute space
* by renaming a linked file into/outof an attribute directory.
* See the comment in zfs_link() for why this is considered bad.
*/
if ((tdzp->z_pflags & ZFS_XATTR) != (sdzp->z_pflags & ZFS_XATTR)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EINVAL));
}
/*
* Lock source and target directory entries. To prevent deadlock,
* a lock ordering must be defined. We lock the directory with
* the smallest object id first, or if it's a tie, the one with
* the lexically first name.
*/
if (sdzp->z_id < tdzp->z_id) {
cmp = -1;
} else if (sdzp->z_id > tdzp->z_id) {
cmp = 1;
} else {
/*
* First compare the two name arguments without
* considering any case folding.
*/
int nofold = (zfsvfs->z_norm & ~U8_TEXTPREP_TOUPPER);
cmp = u8_strcmp(snm, tnm, 0, nofold, U8_UNICODE_LATEST, &error);
ASSERT(error == 0 || !zfsvfs->z_utf8);
if (cmp == 0) {
/*
* POSIX: "If the old argument and the new argument
* both refer to links to the same existing file,
* the rename() function shall return successfully
* and perform no other action."
*/
zfs_exit(zfsvfs, FTAG);
return (0);
}
/*
* If the file system is case-folding, then we may
* have some more checking to do. A case-folding file
* system is either supporting mixed case sensitivity
* access or is completely case-insensitive. Note
* that the file system is always case preserving.
*
* In mixed sensitivity mode case sensitive behavior
* is the default. FIGNORECASE must be used to
* explicitly request case insensitive behavior.
*
* If the source and target names provided differ only
* by case (e.g., a request to rename 'tim' to 'Tim'),
* we will treat this as a special case in the
* case-insensitive mode: as long as the source name
* is an exact match, we will allow this to proceed as
* a name-change request.
*/
if ((zfsvfs->z_case == ZFS_CASE_INSENSITIVE ||
(zfsvfs->z_case == ZFS_CASE_MIXED &&
flags & FIGNORECASE)) &&
u8_strcmp(snm, tnm, 0, zfsvfs->z_norm, U8_UNICODE_LATEST,
&error) == 0) {
/*
* case preserving rename request, require exact
* name matches
*/
zflg |= ZCIEXACT;
zflg &= ~ZCILOOK;
}
}
/*
* If the source and destination directories are the same, we should
* grab the z_name_lock of that directory only once.
*/
if (sdzp == tdzp) {
zflg |= ZHAVELOCK;
rw_enter(&sdzp->z_name_lock, RW_READER);
}
if (cmp < 0) {
serr = zfs_dirent_lock(&sdl, sdzp, snm, &szp,
ZEXISTS | zflg, NULL, NULL);
terr = zfs_dirent_lock(&tdl,
tdzp, tnm, &tzp, ZRENAMING | zflg, NULL, NULL);
} else {
terr = zfs_dirent_lock(&tdl,
tdzp, tnm, &tzp, zflg, NULL, NULL);
serr = zfs_dirent_lock(&sdl,
sdzp, snm, &szp, ZEXISTS | ZRENAMING | zflg,
NULL, NULL);
}
if (serr) {
/*
* Source entry invalid or not there.
*/
if (!terr) {
zfs_dirent_unlock(tdl);
if (tzp)
zrele(tzp);
}
if (sdzp == tdzp)
rw_exit(&sdzp->z_name_lock);
if (strcmp(snm, "..") == 0)
serr = EINVAL;
zfs_exit(zfsvfs, FTAG);
return (serr);
}
if (terr) {
zfs_dirent_unlock(sdl);
zrele(szp);
if (sdzp == tdzp)
rw_exit(&sdzp->z_name_lock);
if (strcmp(tnm, "..") == 0)
terr = EINVAL;
zfs_exit(zfsvfs, FTAG);
return (terr);
}
/*
* If we are using project inheritance, means if the directory has
* ZFS_PROJINHERIT set, then its descendant directories will inherit
* not only the project ID, but also the ZFS_PROJINHERIT flag. Under
* such case, we only allow renames into our tree when the project
* IDs are the same.
*/
if (tdzp->z_pflags & ZFS_PROJINHERIT &&
tdzp->z_projid != szp->z_projid) {
error = SET_ERROR(EXDEV);
goto out;
}
/*
* Must have write access at the source to remove the old entry
* and write access at the target to create the new entry.
* Note that if target and source are the same, this can be
* done in a single check.
*/
if ((error = zfs_zaccess_rename(sdzp, szp, tdzp, tzp, cr, mnt_ns)))
goto out;
if (S_ISDIR(ZTOI(szp)->i_mode)) {
/*
* Check to make sure rename is valid.
* Can't do a move like this: /usr/a/b to /usr/a/b/c/d
*/
if ((error = zfs_rename_lock(szp, tdzp, sdzp, &zl)))
goto out;
}
/*
* Does target exist?
*/
if (tzp) {
if (rflags & RENAME_NOREPLACE) {
error = SET_ERROR(EEXIST);
goto out;
}
/*
* Source and target must be the same type (unless exchanging).
*/
if (!(rflags & RENAME_EXCHANGE)) {
boolean_t s_is_dir = S_ISDIR(ZTOI(szp)->i_mode) != 0;
boolean_t t_is_dir = S_ISDIR(ZTOI(tzp)->i_mode) != 0;
if (s_is_dir != t_is_dir) {
error = SET_ERROR(s_is_dir ? ENOTDIR : EISDIR);
goto out;
}
}
/*
* POSIX dictates that when the source and target
* entries refer to the same file object, rename
* must do nothing and exit without error.
*/
if (szp->z_id == tzp->z_id) {
error = 0;
goto out;
}
} else if (rflags & RENAME_EXCHANGE) {
/* Target must exist for RENAME_EXCHANGE. */
error = SET_ERROR(ENOENT);
goto out;
}
/* Set up inode creation for RENAME_WHITEOUT. */
if (rflags & RENAME_WHITEOUT) {
/*
* Whiteout files are not regular files or directories, so to
* match zfs_create() we do not inherit the project id.
*/
uint64_t wo_projid = ZFS_DEFAULT_PROJID;
error = zfs_zaccess(sdzp, ACE_ADD_FILE, 0, B_FALSE, cr, mnt_ns);
if (error)
goto out;
if (!have_acl) {
error = zfs_acl_ids_create(sdzp, 0, wo_vap, cr, NULL,
&acl_ids, mnt_ns);
if (error)
goto out;
have_acl = B_TRUE;
}
if (zfs_acl_ids_overquota(zfsvfs, &acl_ids, wo_projid)) {
error = SET_ERROR(EDQUOT);
goto out;
}
}
tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_sa(tx, szp->z_sa_hdl, B_FALSE);
dmu_tx_hold_sa(tx, sdzp->z_sa_hdl, B_FALSE);
dmu_tx_hold_zap(tx, sdzp->z_id,
(rflags & RENAME_EXCHANGE) ? TRUE : FALSE, snm);
dmu_tx_hold_zap(tx, tdzp->z_id, TRUE, tnm);
if (sdzp != tdzp) {
dmu_tx_hold_sa(tx, tdzp->z_sa_hdl, B_FALSE);
zfs_sa_upgrade_txholds(tx, tdzp);
}
if (tzp) {
dmu_tx_hold_sa(tx, tzp->z_sa_hdl, B_FALSE);
zfs_sa_upgrade_txholds(tx, tzp);
}
if (rflags & RENAME_WHITEOUT) {
dmu_tx_hold_sa_create(tx, acl_ids.z_aclp->z_acl_bytes +
ZFS_SA_BASE_ATTR_SIZE);
dmu_tx_hold_zap(tx, sdzp->z_id, TRUE, snm);
dmu_tx_hold_sa(tx, sdzp->z_sa_hdl, B_FALSE);
if (!zfsvfs->z_use_sa &&
acl_ids.z_aclp->z_acl_bytes > ZFS_ACE_SPACE) {
dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
0, acl_ids.z_aclp->z_acl_bytes);
}
}
fuid_dirtied = zfsvfs->z_fuid_dirty;
if (fuid_dirtied)
zfs_fuid_txhold(zfsvfs, tx);
zfs_sa_upgrade_txholds(tx, szp);
dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
error = dmu_tx_assign(tx, (waited ? TXG_NOTHROTTLE : 0) | TXG_NOWAIT);
if (error) {
if (zl != NULL)
zfs_rename_unlock(&zl);
zfs_dirent_unlock(sdl);
zfs_dirent_unlock(tdl);
if (sdzp == tdzp)
rw_exit(&sdzp->z_name_lock);
if (error == ERESTART) {
waited = B_TRUE;
dmu_tx_wait(tx);
dmu_tx_abort(tx);
zrele(szp);
if (tzp)
zrele(tzp);
goto top;
}
dmu_tx_abort(tx);
zrele(szp);
if (tzp)
zrele(tzp);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Unlink the source.
*/
szp->z_pflags |= ZFS_AV_MODIFIED;
if (tdzp->z_pflags & ZFS_PROJINHERIT)
szp->z_pflags |= ZFS_PROJINHERIT;
error = sa_update(szp->z_sa_hdl, SA_ZPL_FLAGS(zfsvfs),
(void *)&szp->z_pflags, sizeof (uint64_t), tx);
VERIFY0(error);
error = zfs_link_destroy(sdl, szp, tx, ZRENAMING, NULL);
if (error)
goto commit;
/*
* Unlink the target.
*/
if (tzp) {
int tzflg = zflg;
if (rflags & RENAME_EXCHANGE) {
/* This inode will be re-linked soon. */
tzflg |= ZRENAMING;
tzp->z_pflags |= ZFS_AV_MODIFIED;
if (sdzp->z_pflags & ZFS_PROJINHERIT)
tzp->z_pflags |= ZFS_PROJINHERIT;
error = sa_update(tzp->z_sa_hdl, SA_ZPL_FLAGS(zfsvfs),
(void *)&tzp->z_pflags, sizeof (uint64_t), tx);
ASSERT0(error);
}
error = zfs_link_destroy(tdl, tzp, tx, tzflg, NULL);
if (error)
goto commit_link_szp;
}
/*
* Create the new target links:
* * We always link the target.
* * RENAME_EXCHANGE: Link the old target to the source.
* * RENAME_WHITEOUT: Create a whiteout inode in-place of the source.
*/
error = zfs_link_create(tdl, szp, tx, ZRENAMING);
if (error) {
/*
* If we have removed the existing target, a subsequent call to
* zfs_link_create() to add back the same entry, but with a new
* dnode (szp), should not fail.
*/
ASSERT3P(tzp, ==, NULL);
goto commit_link_tzp;
}
switch (rflags & (RENAME_EXCHANGE | RENAME_WHITEOUT)) {
case RENAME_EXCHANGE:
error = zfs_link_create(sdl, tzp, tx, ZRENAMING);
/*
* The same argument as zfs_link_create() failing for
* szp applies here, since the source directory must
* have had an entry we are replacing.
*/
ASSERT0(error);
if (error)
goto commit_unlink_td_szp;
break;
case RENAME_WHITEOUT:
zfs_mknode(sdzp, wo_vap, tx, cr, 0, &wzp, &acl_ids);
error = zfs_link_create(sdl, wzp, tx, ZNEW);
if (error) {
zfs_znode_delete(wzp, tx);
remove_inode_hash(ZTOI(wzp));
goto commit_unlink_td_szp;
}
break;
}
if (fuid_dirtied)
zfs_fuid_sync(zfsvfs, tx);
switch (rflags & (RENAME_EXCHANGE | RENAME_WHITEOUT)) {
case RENAME_EXCHANGE:
zfs_log_rename_exchange(zilog, tx,
(flags & FIGNORECASE ? TX_CI : 0), sdzp, sdl->dl_name,
tdzp, tdl->dl_name, szp);
break;
case RENAME_WHITEOUT:
zfs_log_rename_whiteout(zilog, tx,
(flags & FIGNORECASE ? TX_CI : 0), sdzp, sdl->dl_name,
tdzp, tdl->dl_name, szp, wzp);
break;
default:
ASSERT0(rflags & ~RENAME_NOREPLACE);
zfs_log_rename(zilog, tx, (flags & FIGNORECASE ? TX_CI : 0),
sdzp, sdl->dl_name, tdzp, tdl->dl_name, szp);
break;
}
commit:
dmu_tx_commit(tx);
out:
if (have_acl)
zfs_acl_ids_free(&acl_ids);
zfs_znode_update_vfs(sdzp);
if (sdzp == tdzp)
rw_exit(&sdzp->z_name_lock);
if (sdzp != tdzp)
zfs_znode_update_vfs(tdzp);
zfs_znode_update_vfs(szp);
zrele(szp);
if (wzp) {
zfs_znode_update_vfs(wzp);
zrele(wzp);
}
if (tzp) {
zfs_znode_update_vfs(tzp);
zrele(tzp);
}
if (zl != NULL)
zfs_rename_unlock(&zl);
zfs_dirent_unlock(sdl);
zfs_dirent_unlock(tdl);
if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
zil_commit(zilog, 0);
zfs_exit(zfsvfs, FTAG);
return (error);
/*
* Clean-up path for broken link state.
*
* At this point we are in a (very) bad state, so we need to do our
* best to correct the state. In particular, all of the nlinks are
* wrong because we were destroying and creating links with ZRENAMING.
*
* In some form, all of these operations have to resolve the state:
*
* * link_destroy() *must* succeed. Fortunately, this is very likely
* since we only just created it.
*
* * link_create()s are allowed to fail (though they shouldn't because
* we only just unlinked them and are putting the entries back
* during clean-up). But if they fail, we can just forcefully drop
* the nlink value to (at the very least) avoid broken nlink values
* -- though in the case of non-empty directories we will have to
* panic (otherwise we'd have a leaked directory with a broken ..).
*/
commit_unlink_td_szp:
VERIFY0(zfs_link_destroy(tdl, szp, tx, ZRENAMING, NULL));
commit_link_tzp:
if (tzp) {
if (zfs_link_create(tdl, tzp, tx, ZRENAMING))
VERIFY0(zfs_drop_nlink(tzp, tx, NULL));
}
commit_link_szp:
if (zfs_link_create(sdl, szp, tx, ZRENAMING))
VERIFY0(zfs_drop_nlink(szp, tx, NULL));
goto commit;
}
/*
* Insert the indicated symbolic reference entry into the directory.
*
* IN: dzp - Directory to contain new symbolic link.
* name - Name of directory entry in dip.
* vap - Attributes of new entry.
* link - Name for new symlink entry.
* cr - credentials of caller.
* flags - case flags
* mnt_ns - user namespace of the mount
*
* OUT: zpp - Znode for new symbolic link.
*
* RETURN: 0 on success, error code on failure.
*
* Timestamps:
* dip - ctime|mtime updated
*/
int
zfs_symlink(znode_t *dzp, char *name, vattr_t *vap, char *link,
znode_t **zpp, cred_t *cr, int flags, zidmap_t *mnt_ns)
{
znode_t *zp;
zfs_dirlock_t *dl;
dmu_tx_t *tx;
zfsvfs_t *zfsvfs = ZTOZSB(dzp);
zilog_t *zilog;
uint64_t len = strlen(link);
int error;
int zflg = ZNEW;
zfs_acl_ids_t acl_ids;
boolean_t fuid_dirtied;
uint64_t txtype = TX_SYMLINK;
boolean_t waited = B_FALSE;
ASSERT(S_ISLNK(vap->va_mode));
if (name == NULL)
return (SET_ERROR(EINVAL));
if ((error = zfs_enter_verify_zp(zfsvfs, dzp, FTAG)) != 0)
return (error);
zilog = zfsvfs->z_log;
if (zfsvfs->z_utf8 && u8_validate(name, strlen(name),
NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EILSEQ));
}
if (flags & FIGNORECASE)
zflg |= ZCILOOK;
if (len > MAXPATHLEN) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(ENAMETOOLONG));
}
if ((error = zfs_acl_ids_create(dzp, 0,
vap, cr, NULL, &acl_ids, mnt_ns)) != 0) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
top:
*zpp = NULL;
/*
* Attempt to lock directory; fail if entry already exists.
*/
error = zfs_dirent_lock(&dl, dzp, name, &zp, zflg, NULL, NULL);
if (error) {
zfs_acl_ids_free(&acl_ids);
zfs_exit(zfsvfs, FTAG);
return (error);
}
if ((error = zfs_zaccess(dzp, ACE_ADD_FILE, 0, B_FALSE, cr, mnt_ns))) {
zfs_acl_ids_free(&acl_ids);
zfs_dirent_unlock(dl);
zfs_exit(zfsvfs, FTAG);
return (error);
}
if (zfs_acl_ids_overquota(zfsvfs, &acl_ids, ZFS_DEFAULT_PROJID)) {
zfs_acl_ids_free(&acl_ids);
zfs_dirent_unlock(dl);
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EDQUOT));
}
tx = dmu_tx_create(zfsvfs->z_os);
fuid_dirtied = zfsvfs->z_fuid_dirty;
dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, MAX(1, len));
dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name);
dmu_tx_hold_sa_create(tx, acl_ids.z_aclp->z_acl_bytes +
ZFS_SA_BASE_ATTR_SIZE + len);
dmu_tx_hold_sa(tx, dzp->z_sa_hdl, B_FALSE);
if (!zfsvfs->z_use_sa && acl_ids.z_aclp->z_acl_bytes > ZFS_ACE_SPACE) {
dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0,
acl_ids.z_aclp->z_acl_bytes);
}
if (fuid_dirtied)
zfs_fuid_txhold(zfsvfs, tx);
error = dmu_tx_assign(tx, (waited ? TXG_NOTHROTTLE : 0) | TXG_NOWAIT);
if (error) {
zfs_dirent_unlock(dl);
if (error == ERESTART) {
waited = B_TRUE;
dmu_tx_wait(tx);
dmu_tx_abort(tx);
goto top;
}
zfs_acl_ids_free(&acl_ids);
dmu_tx_abort(tx);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Create a new object for the symlink.
* for version 4 ZPL datasets the symlink will be an SA attribute
*/
zfs_mknode(dzp, vap, tx, cr, 0, &zp, &acl_ids);
if (fuid_dirtied)
zfs_fuid_sync(zfsvfs, tx);
mutex_enter(&zp->z_lock);
if (zp->z_is_sa)
error = sa_update(zp->z_sa_hdl, SA_ZPL_SYMLINK(zfsvfs),
link, len, tx);
else
zfs_sa_symlink(zp, link, len, tx);
mutex_exit(&zp->z_lock);
zp->z_size = len;
(void) sa_update(zp->z_sa_hdl, SA_ZPL_SIZE(zfsvfs),
&zp->z_size, sizeof (zp->z_size), tx);
/*
* Insert the new object into the directory.
*/
error = zfs_link_create(dl, zp, tx, ZNEW);
if (error != 0) {
zfs_znode_delete(zp, tx);
remove_inode_hash(ZTOI(zp));
} else {
if (flags & FIGNORECASE)
txtype |= TX_CI;
zfs_log_symlink(zilog, tx, txtype, dzp, zp, name, link);
zfs_znode_update_vfs(dzp);
zfs_znode_update_vfs(zp);
}
zfs_acl_ids_free(&acl_ids);
dmu_tx_commit(tx);
zfs_dirent_unlock(dl);
if (error == 0) {
*zpp = zp;
if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
zil_commit(zilog, 0);
} else {
zrele(zp);
}
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Return, in the buffer contained in the provided uio structure,
* the symbolic path referred to by ip.
*
* IN: ip - inode of symbolic link
* uio - structure to contain the link path.
* cr - credentials of caller.
*
* RETURN: 0 if success
* error code if failure
*
* Timestamps:
* ip - atime updated
*/
int
zfs_readlink(struct inode *ip, zfs_uio_t *uio, cred_t *cr)
{
(void) cr;
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
int error;
if ((error = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (error);
mutex_enter(&zp->z_lock);
if (zp->z_is_sa)
error = sa_lookup_uio(zp->z_sa_hdl,
SA_ZPL_SYMLINK(zfsvfs), uio);
else
error = zfs_sa_readlink(zp, uio);
mutex_exit(&zp->z_lock);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Insert a new entry into directory tdzp referencing szp.
*
* IN: tdzp - Directory to contain new entry.
* szp - znode of new entry.
* name - name of new entry.
* cr - credentials of caller.
* flags - case flags.
*
* RETURN: 0 if success
* error code if failure
*
* Timestamps:
* tdzp - ctime|mtime updated
* szp - ctime updated
*/
int
zfs_link(znode_t *tdzp, znode_t *szp, char *name, cred_t *cr,
int flags)
{
struct inode *sip = ZTOI(szp);
znode_t *tzp;
zfsvfs_t *zfsvfs = ZTOZSB(tdzp);
zilog_t *zilog;
zfs_dirlock_t *dl;
dmu_tx_t *tx;
int error;
int zf = ZNEW;
uint64_t parent;
uid_t owner;
boolean_t waited = B_FALSE;
boolean_t is_tmpfile = 0;
uint64_t txg;
is_tmpfile = (sip->i_nlink == 0 && (sip->i_state & I_LINKABLE));
ASSERT(S_ISDIR(ZTOI(tdzp)->i_mode));
if (name == NULL)
return (SET_ERROR(EINVAL));
if ((error = zfs_enter_verify_zp(zfsvfs, tdzp, FTAG)) != 0)
return (error);
zilog = zfsvfs->z_log;
/*
* POSIX dictates that we return EPERM here.
* Better choices include ENOTSUP or EISDIR.
*/
if (S_ISDIR(sip->i_mode)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EPERM));
}
if ((error = zfs_verify_zp(szp)) != 0) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* If we are using project inheritance, means if the directory has
* ZFS_PROJINHERIT set, then its descendant directories will inherit
* not only the project ID, but also the ZFS_PROJINHERIT flag. Under
* such case, we only allow hard link creation in our tree when the
* project IDs are the same.
*/
if (tdzp->z_pflags & ZFS_PROJINHERIT &&
tdzp->z_projid != szp->z_projid) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EXDEV));
}
/*
* We check i_sb because snapshots and the ctldir must have different
* super blocks.
*/
if (sip->i_sb != ZTOI(tdzp)->i_sb || zfsctl_is_node(sip)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EXDEV));
}
/* Prevent links to .zfs/shares files */
if ((error = sa_lookup(szp->z_sa_hdl, SA_ZPL_PARENT(zfsvfs),
&parent, sizeof (uint64_t))) != 0) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
if (parent == zfsvfs->z_shares_dir) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EPERM));
}
if (zfsvfs->z_utf8 && u8_validate(name,
strlen(name), NULL, U8_VALIDATE_ENTIRE, &error) < 0) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EILSEQ));
}
if (flags & FIGNORECASE)
zf |= ZCILOOK;
/*
* We do not support links between attributes and non-attributes
* because of the potential security risk of creating links
* into "normal" file space in order to circumvent restrictions
* imposed in attribute space.
*/
if ((szp->z_pflags & ZFS_XATTR) != (tdzp->z_pflags & ZFS_XATTR)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EINVAL));
}
owner = zfs_fuid_map_id(zfsvfs, KUID_TO_SUID(sip->i_uid),
cr, ZFS_OWNER);
if (owner != crgetuid(cr) && secpolicy_basic_link(cr) != 0) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EPERM));
}
if ((error = zfs_zaccess(tdzp, ACE_ADD_FILE, 0, B_FALSE, cr,
zfs_init_idmap))) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
top:
/*
* Attempt to lock directory; fail if entry already exists.
*/
error = zfs_dirent_lock(&dl, tdzp, name, &tzp, zf, NULL, NULL);
if (error) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_sa(tx, szp->z_sa_hdl, B_FALSE);
dmu_tx_hold_zap(tx, tdzp->z_id, TRUE, name);
if (is_tmpfile)
dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
zfs_sa_upgrade_txholds(tx, szp);
zfs_sa_upgrade_txholds(tx, tdzp);
error = dmu_tx_assign(tx, (waited ? TXG_NOTHROTTLE : 0) | TXG_NOWAIT);
if (error) {
zfs_dirent_unlock(dl);
if (error == ERESTART) {
waited = B_TRUE;
dmu_tx_wait(tx);
dmu_tx_abort(tx);
goto top;
}
dmu_tx_abort(tx);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/* unmark z_unlinked so zfs_link_create will not reject */
if (is_tmpfile)
szp->z_unlinked = B_FALSE;
error = zfs_link_create(dl, szp, tx, 0);
if (error == 0) {
uint64_t txtype = TX_LINK;
/*
* tmpfile is created to be in z_unlinkedobj, so remove it.
* Also, we don't log in ZIL, because all previous file
* operation on the tmpfile are ignored by ZIL. Instead we
* always wait for txg to sync to make sure all previous
* operation are sync safe.
*/
if (is_tmpfile) {
VERIFY(zap_remove_int(zfsvfs->z_os,
zfsvfs->z_unlinkedobj, szp->z_id, tx) == 0);
} else {
if (flags & FIGNORECASE)
txtype |= TX_CI;
zfs_log_link(zilog, tx, txtype, tdzp, szp, name);
}
} else if (is_tmpfile) {
/* restore z_unlinked since when linking failed */
szp->z_unlinked = B_TRUE;
}
txg = dmu_tx_get_txg(tx);
dmu_tx_commit(tx);
zfs_dirent_unlock(dl);
if (!is_tmpfile && zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
zil_commit(zilog, 0);
if (is_tmpfile && zfsvfs->z_os->os_sync != ZFS_SYNC_DISABLED)
txg_wait_synced(dmu_objset_pool(zfsvfs->z_os), txg);
zfs_znode_update_vfs(tdzp);
zfs_znode_update_vfs(szp);
zfs_exit(zfsvfs, FTAG);
return (error);
}
static void
zfs_putpage_sync_commit_cb(void *arg)
{
struct page *pp = arg;
ClearPageError(pp);
end_page_writeback(pp);
}
static void
zfs_putpage_async_commit_cb(void *arg)
{
struct page *pp = arg;
znode_t *zp = ITOZ(pp->mapping->host);
ClearPageError(pp);
end_page_writeback(pp);
atomic_dec_32(&zp->z_async_writes_cnt);
}
/*
* Push a page out to disk, once the page is on stable storage the
* registered commit callback will be run as notification of completion.
*
* IN: ip - page mapped for inode.
* pp - page to push (page is locked)
* wbc - writeback control data
* for_sync - does the caller intend to wait synchronously for the
* page writeback to complete?
*
* RETURN: 0 if success
* error code if failure
*
* Timestamps:
* ip - ctime|mtime updated
*/
int
zfs_putpage(struct inode *ip, struct page *pp, struct writeback_control *wbc,
boolean_t for_sync)
{
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
loff_t offset;
loff_t pgoff;
unsigned int pglen;
dmu_tx_t *tx;
caddr_t va;
int err = 0;
uint64_t mtime[2], ctime[2];
inode_timespec_t tmp_ts;
sa_bulk_attr_t bulk[3];
int cnt = 0;
struct address_space *mapping;
if ((err = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (err);
ASSERT(PageLocked(pp));
pgoff = page_offset(pp); /* Page byte-offset in file */
offset = i_size_read(ip); /* File length in bytes */
pglen = MIN(PAGE_SIZE, /* Page length in bytes */
P2ROUNDUP(offset, PAGE_SIZE)-pgoff);
/* Page is beyond end of file */
if (pgoff >= offset) {
unlock_page(pp);
zfs_exit(zfsvfs, FTAG);
return (0);
}
/* Truncate page length to end of file */
if (pgoff + pglen > offset)
pglen = offset - pgoff;
#if 0
/*
* FIXME: Allow mmap writes past its quota. The correct fix
* is to register a page_mkwrite() handler to count the page
* against its quota when it is about to be dirtied.
*/
if (zfs_id_overblockquota(zfsvfs, DMU_USERUSED_OBJECT,
KUID_TO_SUID(ip->i_uid)) ||
zfs_id_overblockquota(zfsvfs, DMU_GROUPUSED_OBJECT,
KGID_TO_SGID(ip->i_gid)) ||
(zp->z_projid != ZFS_DEFAULT_PROJID &&
zfs_id_overblockquota(zfsvfs, DMU_PROJECTUSED_OBJECT,
zp->z_projid))) {
err = EDQUOT;
}
#endif
/*
* The ordering here is critical and must adhere to the following
* rules in order to avoid deadlocking in either zfs_read() or
* zfs_free_range() due to a lock inversion.
*
* 1) The page must be unlocked prior to acquiring the range lock.
* This is critical because zfs_read() calls find_lock_page()
* which may block on the page lock while holding the range lock.
*
* 2) Before setting or clearing write back on a page the range lock
* must be held in order to prevent a lock inversion with the
* zfs_free_range() function.
*
* This presents a problem because upon entering this function the
* page lock is already held. To safely acquire the range lock the
* page lock must be dropped. This creates a window where another
* process could truncate, invalidate, dirty, or write out the page.
*
* Therefore, after successfully reacquiring the range and page locks
* the current page state is checked. In the common case everything
* will be as is expected and it can be written out. However, if
* the page state has changed it must be handled accordingly.
*/
mapping = pp->mapping;
redirty_page_for_writepage(wbc, pp);
unlock_page(pp);
zfs_locked_range_t *lr = zfs_rangelock_enter(&zp->z_rangelock,
pgoff, pglen, RL_WRITER);
lock_page(pp);
/* Page mapping changed or it was no longer dirty, we're done */
if (unlikely((mapping != pp->mapping) || !PageDirty(pp))) {
unlock_page(pp);
zfs_rangelock_exit(lr);
zfs_exit(zfsvfs, FTAG);
return (0);
}
/* Another process started write block if required */
if (PageWriteback(pp)) {
unlock_page(pp);
zfs_rangelock_exit(lr);
if (wbc->sync_mode != WB_SYNC_NONE) {
/*
* Speed up any non-sync page writebacks since
* they may take several seconds to complete.
* Refer to the comment in zpl_fsync() for details.
*/
if (atomic_load_32(&zp->z_async_writes_cnt) > 0) {
zil_commit(zfsvfs->z_log, zp->z_id);
}
if (PageWriteback(pp))
#ifdef HAVE_PAGEMAP_FOLIO_WAIT_BIT
folio_wait_bit(page_folio(pp), PG_writeback);
#else
wait_on_page_bit(pp, PG_writeback);
#endif
}
zfs_exit(zfsvfs, FTAG);
return (0);
}
/* Clear the dirty flag the required locks are held */
if (!clear_page_dirty_for_io(pp)) {
unlock_page(pp);
zfs_rangelock_exit(lr);
zfs_exit(zfsvfs, FTAG);
return (0);
}
/*
* Counterpart for redirty_page_for_writepage() above. This page
* was in fact not skipped and should not be counted as if it were.
*/
wbc->pages_skipped--;
if (!for_sync)
atomic_inc_32(&zp->z_async_writes_cnt);
set_page_writeback(pp);
unlock_page(pp);
tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_write(tx, zp->z_id, pgoff, pglen);
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
zfs_sa_upgrade_txholds(tx, zp);
err = dmu_tx_assign(tx, TXG_WAIT);
if (err != 0) {
dmu_tx_abort(tx);
#ifdef HAVE_VFS_FILEMAP_DIRTY_FOLIO
filemap_dirty_folio(page_mapping(pp), page_folio(pp));
#else
__set_page_dirty_nobuffers(pp);
#endif
ClearPageError(pp);
end_page_writeback(pp);
if (!for_sync)
atomic_dec_32(&zp->z_async_writes_cnt);
zfs_rangelock_exit(lr);
zfs_exit(zfsvfs, FTAG);
return (err);
}
va = kmap(pp);
ASSERT3U(pglen, <=, PAGE_SIZE);
dmu_write(zfsvfs->z_os, zp->z_id, pgoff, pglen, va, tx);
kunmap(pp);
SA_ADD_BULK_ATTR(bulk, cnt, SA_ZPL_MTIME(zfsvfs), NULL, &mtime, 16);
SA_ADD_BULK_ATTR(bulk, cnt, SA_ZPL_CTIME(zfsvfs), NULL, &ctime, 16);
SA_ADD_BULK_ATTR(bulk, cnt, SA_ZPL_FLAGS(zfsvfs), NULL,
&zp->z_pflags, 8);
/* Preserve the mtime and ctime provided by the inode */
tmp_ts = zpl_inode_get_mtime(ip);
ZFS_TIME_ENCODE(&tmp_ts, mtime);
tmp_ts = zpl_inode_get_ctime(ip);
ZFS_TIME_ENCODE(&tmp_ts, ctime);
zp->z_atime_dirty = B_FALSE;
zp->z_seq++;
err = sa_bulk_update(zp->z_sa_hdl, bulk, cnt, tx);
boolean_t commit = B_FALSE;
if (wbc->sync_mode != WB_SYNC_NONE) {
/*
* Note that this is rarely called under writepages(), because
* writepages() normally handles the entire commit for
* performance reasons.
*/
commit = B_TRUE;
} else if (!for_sync && atomic_load_32(&zp->z_sync_writes_cnt) > 0) {
/*
* If the caller does not intend to wait synchronously
* for this page writeback to complete and there are active
* synchronous calls on this file, do a commit so that
* the latter don't accidentally end up waiting for
* our writeback to complete. Refer to the comment in
* zpl_fsync() (when HAVE_FSYNC_RANGE is defined) for details.
*/
commit = B_TRUE;
}
zfs_log_write(zfsvfs->z_log, tx, TX_WRITE, zp, pgoff, pglen, commit,
B_FALSE, for_sync ? zfs_putpage_sync_commit_cb :
zfs_putpage_async_commit_cb, pp);
dmu_tx_commit(tx);
zfs_rangelock_exit(lr);
if (commit)
zil_commit(zfsvfs->z_log, zp->z_id);
dataset_kstats_update_write_kstats(&zfsvfs->z_kstat, pglen);
zfs_exit(zfsvfs, FTAG);
return (err);
}
/*
* Update the system attributes when the inode has been dirtied. For the
* moment we only update the mode, atime, mtime, and ctime.
*/
int
zfs_dirty_inode(struct inode *ip, int flags)
{
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
dmu_tx_t *tx;
uint64_t mode, atime[2], mtime[2], ctime[2];
inode_timespec_t tmp_ts;
sa_bulk_attr_t bulk[4];
int error = 0;
int cnt = 0;
if (zfs_is_readonly(zfsvfs) || dmu_objset_is_snapshot(zfsvfs->z_os))
return (0);
if ((error = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (error);
#ifdef I_DIRTY_TIME
/*
* This is the lazytime semantic introduced in Linux 4.0
* This flag will only be called from update_time when lazytime is set.
* (Note, I_DIRTY_SYNC will also set if not lazytime)
* Fortunately mtime and ctime are managed within ZFS itself, so we
* only need to dirty atime.
*/
if (flags == I_DIRTY_TIME) {
zp->z_atime_dirty = B_TRUE;
goto out;
}
#endif
tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
zfs_sa_upgrade_txholds(tx, zp);
error = dmu_tx_assign(tx, TXG_WAIT);
if (error) {
dmu_tx_abort(tx);
goto out;
}
mutex_enter(&zp->z_lock);
zp->z_atime_dirty = B_FALSE;
SA_ADD_BULK_ATTR(bulk, cnt, SA_ZPL_MODE(zfsvfs), NULL, &mode, 8);
SA_ADD_BULK_ATTR(bulk, cnt, SA_ZPL_ATIME(zfsvfs), NULL, &atime, 16);
SA_ADD_BULK_ATTR(bulk, cnt, SA_ZPL_MTIME(zfsvfs), NULL, &mtime, 16);
SA_ADD_BULK_ATTR(bulk, cnt, SA_ZPL_CTIME(zfsvfs), NULL, &ctime, 16);
/* Preserve the mode, mtime and ctime provided by the inode */
tmp_ts = zpl_inode_get_atime(ip);
ZFS_TIME_ENCODE(&tmp_ts, atime);
tmp_ts = zpl_inode_get_mtime(ip);
ZFS_TIME_ENCODE(&tmp_ts, mtime);
tmp_ts = zpl_inode_get_ctime(ip);
ZFS_TIME_ENCODE(&tmp_ts, ctime);
mode = ip->i_mode;
zp->z_mode = mode;
error = sa_bulk_update(zp->z_sa_hdl, bulk, cnt, tx);
mutex_exit(&zp->z_lock);
dmu_tx_commit(tx);
out:
zfs_exit(zfsvfs, FTAG);
return (error);
}
void
zfs_inactive(struct inode *ip)
{
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
uint64_t atime[2];
int error;
int need_unlock = 0;
/* Only read lock if we haven't already write locked, e.g. rollback */
if (!RW_WRITE_HELD(&zfsvfs->z_teardown_inactive_lock)) {
need_unlock = 1;
rw_enter(&zfsvfs->z_teardown_inactive_lock, RW_READER);
}
if (zp->z_sa_hdl == NULL) {
if (need_unlock)
rw_exit(&zfsvfs->z_teardown_inactive_lock);
return;
}
if (zp->z_atime_dirty && zp->z_unlinked == B_FALSE) {
dmu_tx_t *tx = dmu_tx_create(zfsvfs->z_os);
dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_FALSE);
zfs_sa_upgrade_txholds(tx, zp);
error = dmu_tx_assign(tx, TXG_WAIT);
if (error) {
dmu_tx_abort(tx);
} else {
inode_timespec_t tmp_atime;
tmp_atime = zpl_inode_get_atime(ip);
ZFS_TIME_ENCODE(&tmp_atime, atime);
mutex_enter(&zp->z_lock);
(void) sa_update(zp->z_sa_hdl, SA_ZPL_ATIME(zfsvfs),
(void *)&atime, sizeof (atime), tx);
zp->z_atime_dirty = B_FALSE;
mutex_exit(&zp->z_lock);
dmu_tx_commit(tx);
}
}
zfs_zinactive(zp);
if (need_unlock)
rw_exit(&zfsvfs->z_teardown_inactive_lock);
}
/*
* Fill pages with data from the disk.
*/
static int
zfs_fillpage(struct inode *ip, struct page *pp)
{
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
loff_t i_size = i_size_read(ip);
u_offset_t io_off = page_offset(pp);
size_t io_len = PAGE_SIZE;
ASSERT3U(io_off, <, i_size);
if (io_off + io_len > i_size)
io_len = i_size - io_off;
void *va = kmap(pp);
int error = dmu_read(zfsvfs->z_os, zp->z_id, io_off,
io_len, va, DMU_READ_PREFETCH);
if (io_len != PAGE_SIZE)
memset((char *)va + io_len, 0, PAGE_SIZE - io_len);
kunmap(pp);
if (error) {
/* convert checksum errors into IO errors */
if (error == ECKSUM)
error = SET_ERROR(EIO);
SetPageError(pp);
ClearPageUptodate(pp);
} else {
ClearPageError(pp);
SetPageUptodate(pp);
if (!PagePrivate(pp)) {
/*
* Set private bit so page migration will wait for us to
* finish writeback before calling migrate_folio().
*/
SetPagePrivate(pp);
get_page(pp);
}
}
return (error);
}
/*
* Uses zfs_fillpage to read data from the file and fill the page.
*
* IN: ip - inode of file to get data from.
* pp - page to read
*
* RETURN: 0 on success, error code on failure.
*
* Timestamps:
* vp - atime updated
*/
int
zfs_getpage(struct inode *ip, struct page *pp)
{
zfsvfs_t *zfsvfs = ITOZSB(ip);
znode_t *zp = ITOZ(ip);
int error;
loff_t i_size = i_size_read(ip);
u_offset_t io_off = page_offset(pp);
size_t io_len = PAGE_SIZE;
if ((error = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (error);
ASSERT3U(io_off, <, i_size);
if (io_off + io_len > i_size)
io_len = i_size - io_off;
/*
* It is important to hold the rangelock here because it is possible
* a Direct I/O write or block clone might be taking place at the same
* time that a page is being faulted in through filemap_fault(). With
* Direct I/O writes and block cloning db->db_data will be set to NULL
* with dbuf_clear_data() in dmu_buif_will_clone_or_dio(). If the
* rangelock is not held, then there is a race between faulting in a
* page and writing out a Direct I/O write or block cloning. Without
* the rangelock a NULL pointer dereference can occur in
* dmu_read_impl() for db->db_data during the mempcy operation when
* zfs_fillpage() calls dmu_read().
*/
zfs_locked_range_t *lr = zfs_rangelock_tryenter(&zp->z_rangelock,
io_off, io_len, RL_READER);
if (lr == NULL) {
/*
* It is important to drop the page lock before grabbing the
* rangelock to avoid another deadlock between here and
* zfs_write() -> update_pages(). update_pages() holds both the
* rangelock and the page lock.
*/
get_page(pp);
unlock_page(pp);
lr = zfs_rangelock_enter(&zp->z_rangelock, io_off,
io_len, RL_READER);
lock_page(pp);
put_page(pp);
}
error = zfs_fillpage(ip, pp);
zfs_rangelock_exit(lr);
if (error == 0)
dataset_kstats_update_read_kstats(&zfsvfs->z_kstat, PAGE_SIZE);
zfs_exit(zfsvfs, FTAG);
return (error);
}
/*
* Check ZFS specific permissions to memory map a section of a file.
*
* IN: ip - inode of the file to mmap
* off - file offset
* addrp - start address in memory region
* len - length of memory region
* vm_flags- address flags
*
* RETURN: 0 if success
* error code if failure
*/
int
zfs_map(struct inode *ip, offset_t off, caddr_t *addrp, size_t len,
unsigned long vm_flags)
{
(void) addrp;
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
int error;
if ((error = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (error);
if ((vm_flags & VM_WRITE) && (vm_flags & VM_SHARED) &&
(zp->z_pflags & (ZFS_IMMUTABLE | ZFS_READONLY | ZFS_APPENDONLY))) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EPERM));
}
if ((vm_flags & (VM_READ | VM_EXEC)) &&
(zp->z_pflags & ZFS_AV_QUARANTINED)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EACCES));
}
if (off < 0 || len > MAXOFFSET_T - off) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(ENXIO));
}
zfs_exit(zfsvfs, FTAG);
return (0);
}
/*
* Free or allocate space in a file. Currently, this function only
* supports the `F_FREESP' command. However, this command is somewhat
* misnamed, as its functionality includes the ability to allocate as
* well as free space.
*
* IN: zp - znode of file to free data in.
* cmd - action to take (only F_FREESP supported).
* bfp - section of file to free/alloc.
* flag - current file open mode flags.
* offset - current file offset.
* cr - credentials of caller.
*
* RETURN: 0 on success, error code on failure.
*
* Timestamps:
* zp - ctime|mtime updated
*/
int
zfs_space(znode_t *zp, int cmd, flock64_t *bfp, int flag,
offset_t offset, cred_t *cr)
{
(void) offset;
zfsvfs_t *zfsvfs = ZTOZSB(zp);
uint64_t off, len;
int error;
if ((error = zfs_enter_verify_zp(zfsvfs, zp, FTAG)) != 0)
return (error);
if (cmd != F_FREESP) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EINVAL));
}
/*
* Callers might not be able to detect properly that we are read-only,
* so check it explicitly here.
*/
if (zfs_is_readonly(zfsvfs)) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EROFS));
}
if (bfp->l_len < 0) {
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(EINVAL));
}
/*
* Permissions aren't checked on Solaris because on this OS
* zfs_space() can only be called with an opened file handle.
* On Linux we can get here through truncate_range() which
* operates directly on inodes, so we need to check access rights.
*/
if ((error = zfs_zaccess(zp, ACE_WRITE_DATA, 0, B_FALSE, cr,
zfs_init_idmap))) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
off = bfp->l_start;
len = bfp->l_len; /* 0 means from off to end of file */
error = zfs_freesp(zp, off, len, flag, TRUE);
zfs_exit(zfsvfs, FTAG);
return (error);
}
int
zfs_fid(struct inode *ip, fid_t *fidp)
{
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ITOZSB(ip);
uint32_t gen;
uint64_t gen64;
uint64_t object = zp->z_id;
zfid_short_t *zfid;
int size, i, error;
if ((error = zfs_enter(zfsvfs, FTAG)) != 0)
return (error);
if (fidp->fid_len < SHORT_FID_LEN) {
fidp->fid_len = SHORT_FID_LEN;
zfs_exit(zfsvfs, FTAG);
return (SET_ERROR(ENOSPC));
}
if ((error = zfs_verify_zp(zp)) != 0) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
if ((error = sa_lookup(zp->z_sa_hdl, SA_ZPL_GEN(zfsvfs),
&gen64, sizeof (uint64_t))) != 0) {
zfs_exit(zfsvfs, FTAG);
return (error);
}
gen = (uint32_t)gen64;
size = SHORT_FID_LEN;
zfid = (zfid_short_t *)fidp;
zfid->zf_len = size;
for (i = 0; i < sizeof (zfid->zf_object); i++)
zfid->zf_object[i] = (uint8_t)(object >> (8 * i));
/* Must have a non-zero generation number to distinguish from .zfs */
if (gen == 0)
gen = 1;
for (i = 0; i < sizeof (zfid->zf_gen); i++)
zfid->zf_gen[i] = (uint8_t)(gen >> (8 * i));
zfs_exit(zfsvfs, FTAG);
return (0);
}
#if defined(_KERNEL)
EXPORT_SYMBOL(zfs_open);
EXPORT_SYMBOL(zfs_close);
EXPORT_SYMBOL(zfs_lookup);
EXPORT_SYMBOL(zfs_create);
EXPORT_SYMBOL(zfs_tmpfile);
EXPORT_SYMBOL(zfs_remove);
EXPORT_SYMBOL(zfs_mkdir);
EXPORT_SYMBOL(zfs_rmdir);
EXPORT_SYMBOL(zfs_readdir);
EXPORT_SYMBOL(zfs_getattr_fast);
EXPORT_SYMBOL(zfs_setattr);
EXPORT_SYMBOL(zfs_rename);
EXPORT_SYMBOL(zfs_symlink);
EXPORT_SYMBOL(zfs_readlink);
EXPORT_SYMBOL(zfs_link);
EXPORT_SYMBOL(zfs_inactive);
EXPORT_SYMBOL(zfs_space);
EXPORT_SYMBOL(zfs_fid);
EXPORT_SYMBOL(zfs_getpage);
EXPORT_SYMBOL(zfs_putpage);
EXPORT_SYMBOL(zfs_dirty_inode);
EXPORT_SYMBOL(zfs_map);
/* CSTYLED */
module_param(zfs_delete_blocks, ulong, 0644);
MODULE_PARM_DESC(zfs_delete_blocks, "Delete files larger than N blocks async");
#endif