Exemplo n.º 1
0
static int
zpl_writepages(struct address_space *mapping, struct writeback_control *wbc)
{
	znode_t		*zp = ITOZ(mapping->host);
	zfs_sb_t	*zsb = ITOZSB(mapping->host);
	enum writeback_sync_modes sync_mode;
	int result;

	ZFS_ENTER(zsb);
	if (zsb->z_os->os_sync == ZFS_SYNC_ALWAYS)
		wbc->sync_mode = WB_SYNC_ALL;
	ZFS_EXIT(zsb);
	sync_mode = wbc->sync_mode;

	/*
	 * We don't want to run write_cache_pages() in SYNC mode here, because
	 * that would make putpage() wait for a single page to be committed to
	 * disk every single time, resulting in atrocious performance. Instead
	 * we run it once in non-SYNC mode so that the ZIL gets all the data,
	 * and then we commit it all in one go.
	 */
	wbc->sync_mode = WB_SYNC_NONE;
	result = write_cache_pages(mapping, wbc, zpl_putpage, mapping);
	if (sync_mode != wbc->sync_mode) {
		ZFS_ENTER(zsb);
		ZFS_VERIFY_ZP(zp);
		if (zsb->z_log != NULL)
			zil_commit(zsb->z_log, zp->z_id);
		ZFS_EXIT(zsb);

		/*
		 * We need to call write_cache_pages() again (we can't just
		 * return after the commit) because the previous call in
		 * non-SYNC mode does not guarantee that we got all the dirty
		 * pages (see the implementation of write_cache_pages() for
		 * details). That being said, this is a no-op in most cases.
		 */
		wbc->sync_mode = sync_mode;
		result = write_cache_pages(mapping, wbc, zpl_putpage, mapping);
	}
	return (result);
}
Exemplo n.º 2
0
/*
 * Lookup/Create an extended attribute entry.
 *
 * Input arguments:
 *	dzp	- znode for hidden attribute directory
 *	name	- name of attribute
 *	flag	- ZNEW: if the entry already exists, fail with EEXIST.
 *		  ZEXISTS: if the entry does not exist, fail with ENOENT.
 *
 * Output arguments:
 *	vpp	- pointer to the vnode for the entry (NULL if there isn't one)
 *
 * Return value: 0 on success or errno value on failure.
 */
int
zfs_obtain_xattr(znode_t *dzp, const char *name, mode_t mode, cred_t *cr,
                 vnode_t **vpp, int flag)
{
	znode_t  *xzp = NULL;
	zfsvfs_t  *zfsvfs = dzp->z_zfsvfs;
	zilog_t  *zilog;
	zfs_dirlock_t  *dl;
	dmu_tx_t  *tx;
	struct vnode_attr  vattr;
	int error;
	struct componentname cn;
	zfs_acl_ids_t	acl_ids;

	/* zfs_dirent_lock() expects a component name */
	bzero(&cn, sizeof (cn));
	cn.cn_nameiop = LOOKUP;
	cn.cn_flags = ISLASTCN;
	cn.cn_nameptr = (char *)name;
	cn.cn_namelen = strlen(name);

    ZFS_ENTER(zfsvfs);
    ZFS_VERIFY_ZP(dzp);
    zilog = zfsvfs->z_log;

	VATTR_INIT(&vattr);
	VATTR_SET(&vattr, va_type, VREG);
	VATTR_SET(&vattr, va_mode, mode & ~S_IFMT);

	if ((error = zfs_acl_ids_create(dzp, 0,
                                    &vattr, cr, NULL, &acl_ids)) != 0) {
		ZFS_EXIT(zfsvfs);
		return (error);
	}
 top:
	/* Lock the attribute entry name. */
	if ( (error = zfs_dirent_lock(&dl, dzp, (char *)name, &xzp, flag,
                                  NULL, &cn)) ) {
		goto out;
	}
	/* If the name already exists, we're done. */
	if (xzp != NULL) {
		zfs_dirent_unlock(dl);
		goto out;
	}
	tx = dmu_tx_create(zfsvfs->z_os);
	dmu_tx_hold_sa(tx, dzp->z_sa_hdl, B_FALSE);
	dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL);
	//dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
	//dmu_tx_hold_bonus(tx, dzp->z_id);
	dmu_tx_hold_zap(tx, dzp->z_id, TRUE, (char *)name);

#if 1 // FIXME
	if (dzp->z_pflags & ZFS_INHERIT_ACE) {
		dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, SPA_MAXBLOCKSIZE);
	}
#endif
    zfs_sa_upgrade_txholds(tx, dzp);
	error = dmu_tx_assign(tx, TXG_NOWAIT);
	if (error) {
		zfs_dirent_unlock(dl);
		if (error == ERESTART) {
			dmu_tx_wait(tx);
			dmu_tx_abort(tx);
			goto top;
		}
		dmu_tx_abort(tx);
		goto out;
	}

	zfs_mknode(dzp, &vattr, tx, cr, 0, &xzp, &acl_ids);

    /*
      ASSERT(xzp->z_id == zoid);
    */
	(void) zfs_link_create(dl, xzp, tx, ZNEW);
	zfs_log_create(zilog, tx, TX_CREATE, dzp, xzp, (char *)name,
                   NULL /* vsecp */, 0 /*acl_ids.z_fuidp*/, &vattr);
    zfs_acl_ids_free(&acl_ids);
	dmu_tx_commit(tx);
    zfs_znode_wait_vnode(xzp);

	zfs_dirent_unlock(dl);
 out:
	if (error == EEXIST)
		error = ENOATTR;
	if (xzp)
		*vpp = ZTOV(xzp);

    ZFS_EXIT(zfsvfs);
	return (error);
}