zfs_znode.c revision fa9e4066f08beec538e775443c5be79dd423fcab
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (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 http://www.opensolaris.org/os/licensing.
* 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 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/types.h>
#include <sys/param.h>
#include <sys/time.h>
#include <sys/systm.h>
#include <sys/sysmacros.h>
#include <sys/resource.h>
#include <sys/mntent.h>
#include <sys/vfs.h>
#include <sys/vnode.h>
#include <sys/file.h>
#include <sys/kmem.h>
#include <sys/cmn_err.h>
#include <sys/errno.h>
#include <sys/unistd.h>
#include <sys/stat.h>
#include <sys/mode.h>
#include <sys/atomic.h>
#include <vm/pvn.h>
#include "fs/fs_subr.h"
#include <sys/zfs_dir.h>
#include <sys/zfs_acl.h>
#include <sys/zfs_ioctl.h>
#include <sys/zfs_znode.h>
#include <sys/zap.h>
#include <sys/dmu.h>
#include <sys/fs/zfs.h>
struct kmem_cache *znode_cache = NULL;
/*
* Note that znodes can be on one of 2 states:
* ZCACHE_mru - recently used, currently cached
* ZCACHE_mfu - frequently used, currently cached
* When there are no active references to the znode, they
* are linked onto one of the lists in zcache. These are the
* only znodes that can be evicted.
*/
typedef struct zcache_state {
list_t list; /* linked list of evictable znodes in state */
uint64_t lcnt; /* total number of znodes in the linked list */
uint64_t cnt; /* total number of all znodes in this state */
uint64_t hits;
kmutex_t mtx;
} zcache_state_t;
/* The 2 states: */
static zcache_state_t ZCACHE_mru;
static zcache_state_t ZCACHE_mfu;
static struct zcache {
zcache_state_t *mru;
zcache_state_t *mfu;
uint64_t p; /* Target size of mru */
uint64_t c; /* Target size of cache */
uint64_t c_max; /* Maximum target cache size */
/* performance stats */
uint64_t missed;
uint64_t evicted;
uint64_t skipped;
} zcache;
void zcache_kmem_reclaim(void);
#define ZCACHE_MINTIME (hz>>4) /* 62 ms */
/*
* Move the supplied znode to the indicated state. The mutex
* for the znode must be held by the caller.
*/
static void
zcache_change_state(zcache_state_t *new_state, znode_t *zp)
{
/* ASSERT(MUTEX_HELD(hash_mtx)); */
ASSERT(zp->z_active);
if (zp->z_zcache_state) {
ASSERT3U(zp->z_zcache_state->cnt, >=, 1);
atomic_add_64(&zp->z_zcache_state->cnt, -1);
}
atomic_add_64(&new_state->cnt, 1);
zp->z_zcache_state = new_state;
}
static void
zfs_zcache_evict(znode_t *zp, kmutex_t *hash_mtx)
{
zfsvfs_t *zfsvfs = zp->z_zfsvfs;
ASSERT(zp->z_phys);
ASSERT(zp->z_dbuf_held);
zp->z_dbuf_held = 0;
mutex_exit(&zp->z_lock);
dmu_buf_rele(zp->z_dbuf);
mutex_exit(hash_mtx);
VFS_RELE(zfsvfs->z_vfs);
}
/*
* Evict znodes from list until we've removed the specified number
*/
static void
zcache_evict_state(zcache_state_t *state, int64_t cnt, zfsvfs_t *zfsvfs)
{
int znodes_evicted = 0;
znode_t *zp, *zp_prev;
kmutex_t *hash_mtx;
ASSERT(state == zcache.mru || state == zcache.mfu);
mutex_enter(&state->mtx);
for (zp = list_tail(&state->list); zp; zp = zp_prev) {
zp_prev = list_prev(&state->list, zp);
if (zfsvfs && zp->z_zfsvfs != zfsvfs)
continue;
hash_mtx = ZFS_OBJ_MUTEX(zp);
if (mutex_tryenter(hash_mtx)) {
mutex_enter(&zp->z_lock);
list_remove(&zp->z_zcache_state->list, zp);
zp->z_zcache_state->lcnt -= 1;
ASSERT3U(zp->z_zcache_state->cnt, >=, 1);
atomic_add_64(&zp->z_zcache_state->cnt, -1);
zp->z_zcache_state = NULL;
zp->z_zcache_access = 0;
/* drops z_lock and hash_mtx */
zfs_zcache_evict(zp, hash_mtx);
znodes_evicted += 1;
atomic_add_64(&zcache.evicted, 1);
if (znodes_evicted >= cnt)
break;
} else {
atomic_add_64(&zcache.skipped, 1);
}
}
mutex_exit(&state->mtx);
if (znodes_evicted < cnt)
dprintf("only evicted %lld znodes from %x",
(longlong_t)znodes_evicted, state);
}
static void
zcache_adjust(void)
{
uint64_t mrucnt = zcache.mru->lcnt;
uint64_t mfucnt = zcache.mfu->lcnt;
uint64_t p = zcache.p;
uint64_t c = zcache.c;
if (mrucnt > p)
zcache_evict_state(zcache.mru, mrucnt - p, NULL);
if (mfucnt > 0 && mrucnt + mfucnt > c) {
int64_t toevict = MIN(mfucnt, mrucnt + mfucnt - c);
zcache_evict_state(zcache.mfu, toevict, NULL);
}
}
/*
* Flush all *evictable* data from the cache.
* NOTE: this will not touch "active" (i.e. referenced) data.
*/
void
zfs_zcache_flush(zfsvfs_t *zfsvfs)
{
zcache_evict_state(zcache.mru, zcache.mru->lcnt, zfsvfs);
zcache_evict_state(zcache.mfu, zcache.mfu->lcnt, zfsvfs);
}
static void
zcache_try_grow(int64_t cnt)
{
int64_t size;
/*
* If we're almost to the current target cache size,
* increment the target cache size
*/
size = zcache.mru->lcnt + zcache.mfu->lcnt;
if ((zcache.c - size) <= 1) {
atomic_add_64(&zcache.c, cnt);
if (zcache.c > zcache.c_max)
zcache.c = zcache.c_max;
else if (zcache.p + cnt < zcache.c)
atomic_add_64(&zcache.p, cnt);
}
}
/*
* This routine is called whenever a znode is accessed.
*/
static void
zcache_access(znode_t *zp, kmutex_t *hash_mtx)
{
ASSERT(MUTEX_HELD(hash_mtx));
if (zp->z_zcache_state == NULL) {
/*
* This znode is not in the cache.
* Add the new znode to the MRU state.
*/
zcache_try_grow(1);
ASSERT(zp->z_zcache_access == 0);
zp->z_zcache_access = lbolt;
zcache_change_state(zcache.mru, zp);
mutex_exit(hash_mtx);
/*
* If we are using less than 2/3 of our total target
* cache size, bump up the target size for the MRU
* list.
*/
if (zcache.mru->lcnt + zcache.mfu->lcnt < zcache.c*2/3) {
zcache.p = zcache.mru->lcnt + zcache.c/6;
}
zcache_adjust();
atomic_add_64(&zcache.missed, 1);
} else if (zp->z_zcache_state == zcache.mru) {
/*
* This znode has been "accessed" only once so far,
* Move it to the MFU state.
*/
if (lbolt > zp->z_zcache_access + ZCACHE_MINTIME) {
/*
* More than 125ms have passed since we
* instantiated this buffer. Move it to the
* most frequently used state.
*/
zp->z_zcache_access = lbolt;
zcache_change_state(zcache.mfu, zp);
}
atomic_add_64(&zcache.mru->hits, 1);
mutex_exit(hash_mtx);
} else {
ASSERT(zp->z_zcache_state == zcache.mfu);
/*
* This buffer has been accessed more than once.
* Keep it in the MFU state.
*/
atomic_add_64(&zcache.mfu->hits, 1);
mutex_exit(hash_mtx);
}
}
static void
zcache_init(void)
{
zcache.c = 20;
zcache.c_max = 50;
zcache.mru = &ZCACHE_mru;
zcache.mfu = &ZCACHE_mfu;
list_create(&zcache.mru->list, sizeof (znode_t),
offsetof(znode_t, z_zcache_node));
list_create(&zcache.mfu->list, sizeof (znode_t),
offsetof(znode_t, z_zcache_node));
}
static void
zcache_fini(void)
{
zfs_zcache_flush(NULL);
list_destroy(&zcache.mru->list);
list_destroy(&zcache.mfu->list);
}
/*ARGSUSED*/
static void
znode_pageout_func(dmu_buf_t *dbuf, void *user_ptr)
{
znode_t *zp = user_ptr;
vnode_t *vp = ZTOV(zp);
if (vp->v_count == 0) {
vn_invalid(vp);
zfs_znode_free(zp);
}
}
/*ARGSUSED*/
static int
zfs_znode_cache_constructor(void *buf, void *cdrarg, int kmflags)
{
znode_t *zp = buf;
zp->z_vnode = vn_alloc(KM_SLEEP);
zp->z_vnode->v_data = (caddr_t)zp;
mutex_init(&zp->z_lock, NULL, MUTEX_DEFAULT, NULL);
rw_init(&zp->z_map_lock, NULL, RW_DEFAULT, NULL);
rw_init(&zp->z_grow_lock, NULL, RW_DEFAULT, NULL);
rw_init(&zp->z_append_lock, NULL, RW_DEFAULT, NULL);
mutex_init(&zp->z_acl_lock, NULL, MUTEX_DEFAULT, NULL);
zp->z_dbuf_held = 0;
zp->z_dirlocks = 0;
return (0);
}
/*ARGSUSED*/
static void
zfs_znode_cache_destructor(void *buf, void *cdarg)
{
znode_t *zp = buf;
ASSERT(zp->z_dirlocks == 0);
mutex_destroy(&zp->z_lock);
rw_destroy(&zp->z_map_lock);
rw_destroy(&zp->z_grow_lock);
rw_destroy(&zp->z_append_lock);
mutex_destroy(&zp->z_acl_lock);
ASSERT(zp->z_dbuf_held == 0);
ASSERT(ZTOV(zp)->v_count == 0);
vn_free(ZTOV(zp));
}
void
zfs_znode_init(void)
{
/*
* Initialize zcache
*/
ASSERT(znode_cache == NULL);
znode_cache = kmem_cache_create("zfs_znode_cache",
sizeof (znode_t), 0, zfs_znode_cache_constructor,
zfs_znode_cache_destructor, NULL, NULL, NULL, 0);
zcache_init();
}
void
zfs_znode_fini(void)
{
zcache_fini();
/*
* Cleanup vfs & vnode ops
*/
zfs_remove_op_tables();
/*
* Cleanup zcache
*/
if (znode_cache)
kmem_cache_destroy(znode_cache);
znode_cache = NULL;
}
struct vnodeops *zfs_dvnodeops;
struct vnodeops *zfs_fvnodeops;
struct vnodeops *zfs_symvnodeops;
struct vnodeops *zfs_xdvnodeops;
struct vnodeops *zfs_evnodeops;
void
zfs_remove_op_tables()
{
/*
* Remove vfs ops
*/
ASSERT(zfsfstype);
(void) vfs_freevfsops_by_type(zfsfstype);
zfsfstype = 0;
/*
* Remove vnode ops
*/
if (zfs_dvnodeops)
vn_freevnodeops(zfs_dvnodeops);
if (zfs_fvnodeops)
vn_freevnodeops(zfs_fvnodeops);
if (zfs_symvnodeops)
vn_freevnodeops(zfs_symvnodeops);
if (zfs_xdvnodeops)
vn_freevnodeops(zfs_xdvnodeops);
if (zfs_evnodeops)
vn_freevnodeops(zfs_evnodeops);
zfs_dvnodeops = NULL;
zfs_fvnodeops = NULL;
zfs_symvnodeops = NULL;
zfs_xdvnodeops = NULL;
zfs_evnodeops = NULL;
}
extern const fs_operation_def_t zfs_dvnodeops_template[];
extern const fs_operation_def_t zfs_fvnodeops_template[];
extern const fs_operation_def_t zfs_xdvnodeops_template[];
extern const fs_operation_def_t zfs_symvnodeops_template[];
extern const fs_operation_def_t zfs_evnodeops_template[];
int
zfs_create_op_tables()
{
int error;
/*
* zfs_dvnodeops can be set if mod_remove() calls mod_installfs()
* due to a failure to remove the the 2nd modlinkage (zfs_modldrv).
* In this case we just return as the ops vectors are already set up.
*/
if (zfs_dvnodeops)
return (0);
error = vn_make_ops(MNTTYPE_ZFS, zfs_dvnodeops_template,
&zfs_dvnodeops);
if (error)
return (error);
error = vn_make_ops(MNTTYPE_ZFS, zfs_fvnodeops_template,
&zfs_fvnodeops);
if (error)
return (error);
error = vn_make_ops(MNTTYPE_ZFS, zfs_symvnodeops_template,
&zfs_symvnodeops);
if (error)
return (error);
error = vn_make_ops(MNTTYPE_ZFS, zfs_xdvnodeops_template,
&zfs_xdvnodeops);
if (error)
return (error);
error = vn_make_ops(MNTTYPE_ZFS, zfs_evnodeops_template,
&zfs_evnodeops);
return (error);
}
/*
* zfs_init_fs - Initialize the zfsvfs struct and the file system
* incore "master" object. Verify version compatibility.
*/
int
zfs_init_fs(zfsvfs_t *zfsvfs, znode_t **zpp, cred_t *cr)
{
extern int zfsfstype;
objset_t *os = zfsvfs->z_os;
uint64_t zoid;
uint64_t version = ZFS_VERSION;
int i, error;
dmu_object_info_t doi;
dmu_objset_stats_t *stats;
*zpp = NULL;
/*
* XXX - hack to auto-create the pool root filesystem at
* the first attempted mount.
*/
if (dmu_object_info(os, MASTER_NODE_OBJ, &doi) == ENOENT) {
dmu_tx_t *tx = dmu_tx_create(os);
dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, 3); /* master node */
dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, 1); /* delete queue */
dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT); /* root node */
error = dmu_tx_assign(tx, TXG_WAIT);
ASSERT3U(error, ==, 0);
zfs_create_fs(os, cr, tx);
dmu_tx_commit(tx);
}
if (zap_lookup(os, MASTER_NODE_OBJ, ZFS_VERSION_OBJ, 8, 1, &version)) {
return (EINVAL);
} else if (version != ZFS_VERSION) {
(void) printf("Mismatched versions: File system "
"is version %lld on-disk format, which is "
"incompatible with this software version %lld!",
(u_longlong_t)version, ZFS_VERSION);
return (ENOTSUP);
}
/*
* The fsid is 64 bits, composed of an 8-bit fs type, which
* separates our fsid from any other filesystem types, and a
* 56-bit objset unique ID. The objset unique ID is unique to
* all objsets open on this system, provided by unique_create().
* The 8-bit fs type must be put in the low bits of fsid[1]
* because that's where other Solaris filesystems put it.
*/
stats = kmem_alloc(sizeof (dmu_objset_stats_t), KM_SLEEP);
dmu_objset_stats(os, stats);
ASSERT((stats->dds_fsid_guid & ~((1ULL<<56)-1)) == 0);
zfsvfs->z_vfs->vfs_fsid.val[0] = stats->dds_fsid_guid;
zfsvfs->z_vfs->vfs_fsid.val[1] = ((stats->dds_fsid_guid>>32) << 8) |
zfsfstype & 0xFF;
kmem_free(stats, sizeof (dmu_objset_stats_t));
stats = NULL;
if (zap_lookup(os, MASTER_NODE_OBJ, ZFS_ROOT_OBJ, 8, 1, &zoid)) {
return (EINVAL);
}
ASSERT(zoid != 0);
zfsvfs->z_root = zoid;
/*
* Create the per mount vop tables.
*/
/*
* Initialize zget mutex's
*/
for (i = 0; i != ZFS_OBJ_MTX_SZ; i++)
mutex_init(&zfsvfs->z_hold_mtx[i], NULL, MUTEX_DEFAULT, NULL);
error = zfs_zget(zfsvfs, zoid, zpp);
if (error)
return (error);
ASSERT3U((*zpp)->z_id, ==, zoid);
if (zap_lookup(os, MASTER_NODE_OBJ, ZFS_DELETE_QUEUE, 8, 1, &zoid)) {
return (EINVAL);
}
zfsvfs->z_dqueue = zoid;
/*
* Initialize delete head structure
* Thread(s) will be started/stopped via
* readonly_changed_cb() depending
* on whether this is rw/ro mount.
*/
list_create(&zfsvfs->z_delete_head.z_znodes,
sizeof (znode_t), offsetof(znode_t, z_list_node));
return (0);
}
/*
* Construct a new znode/vnode and intialize.
*
* This does not do a call to dmu_set_user() that is
* up to the caller to do, in case you don't want to
* return the znode
*/
znode_t *
zfs_znode_alloc(zfsvfs_t *zfsvfs, dmu_buf_t *db, uint64_t obj_num, int blksz)
{
znode_t *zp;
vnode_t *vp;
zp = kmem_cache_alloc(znode_cache, KM_SLEEP);
ASSERT(zp->z_dirlocks == NULL);
zp->z_phys = db->db_data;
zp->z_zfsvfs = zfsvfs;
zp->z_active = 1;
zp->z_reap = 0;
zp->z_atime_dirty = 0;
zp->z_dbuf_held = 0;
zp->z_mapcnt = 0;
zp->z_last_itx = 0;
zp->z_dbuf = db;
zp->z_id = obj_num;
zp->z_blksz = blksz;
zp->z_seq = 0x7A4653;
bzero(&zp->z_zcache_node, sizeof (list_node_t));
mutex_enter(&zfsvfs->z_znodes_lock);
list_insert_tail(&zfsvfs->z_all_znodes, zp);
mutex_exit(&zfsvfs->z_znodes_lock);
vp = ZTOV(zp);
vn_reinit(vp);
vp->v_vfsp = zfsvfs->z_parent->z_vfs;
vp->v_type = IFTOVT((mode_t)zp->z_phys->zp_mode);
switch (vp->v_type) {
case VDIR:
if (zp->z_phys->zp_flags & ZFS_XATTR) {
vn_setops(vp, zfs_xdvnodeops);
vp->v_flag |= V_XATTRDIR;
} else
vn_setops(vp, zfs_dvnodeops);
break;
case VBLK:
case VCHR:
vp->v_rdev = (dev_t)zp->z_phys->zp_rdev;
/*FALLTHROUGH*/
case VFIFO:
case VSOCK:
case VDOOR:
vn_setops(vp, zfs_fvnodeops);
break;
case VREG:
vp->v_flag |= VMODSORT;
vn_setops(vp, zfs_fvnodeops);
break;
case VLNK:
vn_setops(vp, zfs_symvnodeops);
break;
default:
vn_setops(vp, zfs_evnodeops);
break;
}
return (zp);
}
static void
zfs_znode_dmu_init(znode_t *zp)
{
znode_t *nzp;
zfsvfs_t *zfsvfs = zp->z_zfsvfs;
dmu_buf_t *db = zp->z_dbuf;
mutex_enter(&zp->z_lock);
nzp = dmu_buf_set_user(db, zp, &zp->z_phys, znode_pageout_func);
/*
* there should be no
* concurrent zgets on this object.
*/
ASSERT3P(nzp, ==, NULL);
/*
* Slap on VROOT if we are the root znode
*/
if (zp->z_id == zfsvfs->z_root) {
ZTOV(zp)->v_flag |= VROOT;
}
zp->z_zcache_state = NULL;
zp->z_zcache_access = 0;
ASSERT(zp->z_dbuf_held == 0);
zp->z_dbuf_held = 1;
VFS_HOLD(zfsvfs->z_vfs);
mutex_exit(&zp->z_lock);
vn_exists(ZTOV(zp));
}
/*
* Create a new DMU object to hold a zfs znode.
*
* IN: dzp - parent directory for new znode
* vap - file attributes for new znode
* tx - dmu transaction id for zap operations
* cr - credentials of caller
* flag - flags:
* IS_ROOT_NODE - new object will be root
* IS_XATTR - new object is an attribute
* IS_REPLAY - intent log replay
*
* OUT: oid - ID of created object
*
*/
void
zfs_mknode(znode_t *dzp, vattr_t *vap, uint64_t *oid, dmu_tx_t *tx, cred_t *cr,
uint_t flag, znode_t **zpp, int bonuslen)
{
dmu_buf_t *dbp;
znode_phys_t *pzp;
znode_t *zp;
zfsvfs_t *zfsvfs = dzp->z_zfsvfs;
timestruc_t now;
uint64_t gen;
int err;
ASSERT(vap && (vap->va_mask & (AT_TYPE|AT_MODE)) == (AT_TYPE|AT_MODE));
if (zfsvfs->z_assign >= TXG_INITIAL) { /* ZIL replay */
*oid = vap->va_nodeid;
flag |= IS_REPLAY;
now = vap->va_ctime; /* see zfs_replay_create() */
gen = vap->va_nblocks; /* ditto */
} else {
*oid = 0;
gethrestime(&now);
gen = dmu_tx_get_txg(tx);
}
/*
* Create a new DMU object.
*/
if (vap->va_type == VDIR) {
if (flag & IS_REPLAY) {
err = zap_create_claim(zfsvfs->z_os, *oid,
DMU_OT_DIRECTORY_CONTENTS,
DMU_OT_ZNODE, sizeof (znode_phys_t) + bonuslen, tx);
ASSERT3U(err, ==, 0);
} else {
*oid = zap_create(zfsvfs->z_os,
DMU_OT_DIRECTORY_CONTENTS,
DMU_OT_ZNODE, sizeof (znode_phys_t) + bonuslen, tx);
}
} else {
if (flag & IS_REPLAY) {
err = dmu_object_claim(zfsvfs->z_os, *oid,
DMU_OT_PLAIN_FILE_CONTENTS, 0,
DMU_OT_ZNODE, sizeof (znode_phys_t) + bonuslen, tx);
ASSERT3U(err, ==, 0);
} else {
*oid = dmu_object_alloc(zfsvfs->z_os,
DMU_OT_PLAIN_FILE_CONTENTS, 0,
DMU_OT_ZNODE, sizeof (znode_phys_t) + bonuslen, tx);
}
}
dbp = dmu_bonus_hold(zfsvfs->z_os, *oid);
dmu_buf_will_dirty(dbp, tx);
/*
* Initialize the znode physical data to zero.
*/
ASSERT(dbp->db_size >= sizeof (znode_phys_t));
bzero(dbp->db_data, dbp->db_size);
pzp = dbp->db_data;
/*
* If this is the root, fix up the half-initialized parent pointer
* to reference the just-allocated physical data area.
*/
if (flag & IS_ROOT_NODE) {
dzp->z_phys = pzp;
dzp->z_id = *oid;
}
/*
* If parent is an xattr, so am I.
*/
if (dzp->z_phys->zp_flags & ZFS_XATTR)
flag |= IS_XATTR;
if (vap->va_type == VBLK || vap->va_type == VCHR) {
pzp->zp_rdev = vap->va_rdev;
}
if (vap->va_type == VDIR) {
pzp->zp_size = 2; /* contents ("." and "..") */
pzp->zp_links = (flag & (IS_ROOT_NODE | IS_XATTR)) ? 2 : 1;
}
pzp->zp_parent = dzp->z_id;
if (flag & IS_XATTR)
pzp->zp_flags |= ZFS_XATTR;
pzp->zp_gen = gen;
ZFS_TIME_ENCODE(&now, pzp->zp_crtime);
ZFS_TIME_ENCODE(&now, pzp->zp_ctime);
if (vap->va_mask & AT_ATIME) {
ZFS_TIME_ENCODE(&vap->va_atime, pzp->zp_atime);
} else {
ZFS_TIME_ENCODE(&now, pzp->zp_atime);
}
if (vap->va_mask & AT_MTIME) {
ZFS_TIME_ENCODE(&vap->va_mtime, pzp->zp_mtime);
} else {
ZFS_TIME_ENCODE(&now, pzp->zp_mtime);
}
pzp->zp_mode = MAKEIMODE(vap->va_type, vap->va_mode);
zp = zfs_znode_alloc(zfsvfs, dbp, *oid, 0);
zfs_perm_init(zp, dzp, flag, vap, tx, cr);
if (zpp) {
kmutex_t *hash_mtx = ZFS_OBJ_MUTEX(zp);
mutex_enter(hash_mtx);
zfs_znode_dmu_init(zp);
zcache_access(zp, hash_mtx);
*zpp = zp;
} else {
ZTOV(zp)->v_count = 0;
dmu_buf_rele(dbp);
zfs_znode_free(zp);
}
}
int
zfs_zget(zfsvfs_t *zfsvfs, uint64_t obj_num, znode_t **zpp)
{
dmu_object_info_t doi;
dmu_buf_t *db;
znode_t *zp;
*zpp = NULL;
ZFS_OBJ_HOLD_ENTER(zfsvfs, obj_num);
db = dmu_bonus_hold(zfsvfs->z_os, obj_num);
if (db == NULL) {
ZFS_OBJ_HOLD_EXIT(zfsvfs, obj_num);
return (ENOENT);
}
dmu_object_info_from_db(db, &doi);
if (doi.doi_bonus_type != DMU_OT_ZNODE ||
doi.doi_bonus_size < sizeof (znode_phys_t)) {
dmu_buf_rele(db);
ZFS_OBJ_HOLD_EXIT(zfsvfs, obj_num);
return (EINVAL);
}
dmu_buf_read(db);
ASSERT(db->db_object == obj_num);
ASSERT(db->db_offset == -1);
ASSERT(db->db_data != NULL);
zp = dmu_buf_get_user(db);
if (zp != NULL) {
mutex_enter(&zp->z_lock);
ASSERT3U(zp->z_id, ==, obj_num);
if (zp->z_reap) {
dmu_buf_rele(db);
mutex_exit(&zp->z_lock);
ZFS_OBJ_HOLD_EXIT(zfsvfs, obj_num);
return (ENOENT);
} else if (zp->z_dbuf_held) {
dmu_buf_rele(db);
} else {
zp->z_dbuf_held = 1;
VFS_HOLD(zfsvfs->z_vfs);
}
if (zp->z_active == 0) {
zp->z_active = 1;
if (list_link_active(&zp->z_zcache_node)) {
mutex_enter(&zp->z_zcache_state->mtx);
list_remove(&zp->z_zcache_state->list, zp);
zp->z_zcache_state->lcnt -= 1;
mutex_exit(&zp->z_zcache_state->mtx);
}
}
VN_HOLD(ZTOV(zp));
mutex_exit(&zp->z_lock);
zcache_access(zp, ZFS_OBJ_MUTEX(zp));
*zpp = zp;
return (0);
}
/*
* Not found create new znode/vnode
*/
zp = zfs_znode_alloc(zfsvfs, db, obj_num, doi.doi_data_block_size);
ASSERT3U(zp->z_id, ==, obj_num);
zfs_znode_dmu_init(zp);
zcache_access(zp, ZFS_OBJ_MUTEX(zp));
*zpp = zp;
return (0);
}
void
zfs_znode_delete(znode_t *zp, dmu_tx_t *tx)
{
zfsvfs_t *zfsvfs = zp->z_zfsvfs;
int error;
ZFS_OBJ_HOLD_ENTER(zfsvfs, zp->z_id);
if (zp->z_phys->zp_acl.z_acl_extern_obj) {
error = dmu_object_free(zfsvfs->z_os,
zp->z_phys->zp_acl.z_acl_extern_obj, tx);
ASSERT3U(error, ==, 0);
}
if (zp->z_zcache_state) {
ASSERT3U(zp->z_zcache_state->cnt, >=, 1);
atomic_add_64(&zp->z_zcache_state->cnt, -1);
}
error = dmu_object_free(zfsvfs->z_os, zp->z_id, tx);
ASSERT3U(error, ==, 0);
zp->z_dbuf_held = 0;
ZFS_OBJ_HOLD_EXIT(zfsvfs, zp->z_id);
dmu_buf_rele(zp->z_dbuf);
}
void
zfs_zinactive(znode_t *zp)
{
vnode_t *vp = ZTOV(zp);
zfsvfs_t *zfsvfs = zp->z_zfsvfs;
uint64_t z_id = zp->z_id;
ASSERT(zp->z_dbuf_held && zp->z_phys);
/*
* Don't allow a zfs_zget() while were trying to release this znode
*/
ZFS_OBJ_HOLD_ENTER(zfsvfs, z_id);
mutex_enter(&zp->z_lock);
mutex_enter(&vp->v_lock);
vp->v_count--;
if (vp->v_count > 0 || vn_has_cached_data(vp)) {
/*
* If the hold count is greater than zero, somebody has
* obtained a new reference on this znode while we were
* processing it here, so we are done. If we still have
* mapped pages then we are also done, since we don't
* want to inactivate the znode until the pages get pushed.
*
* XXX - if vn_has_cached_data(vp) is true, but count == 0,
* this seems like it would leave the znode hanging with
* no chance to go inactive...
*/
mutex_exit(&vp->v_lock);
mutex_exit(&zp->z_lock);
ZFS_OBJ_HOLD_EXIT(zfsvfs, z_id);
return;
}
mutex_exit(&vp->v_lock);
zp->z_active = 0;
/*
* If this was the last reference to a file with no links,
* remove the file from the file system.
*/
if (zp->z_reap) {
mutex_exit(&zp->z_lock);
ZFS_OBJ_HOLD_EXIT(zfsvfs, z_id);
ASSERT3U(zp->z_zcache_state->cnt, >=, 1);
atomic_add_64(&zp->z_zcache_state->cnt, -1);
zp->z_zcache_state = NULL;
/* XATTR files are not put on the delete queue */
if (zp->z_phys->zp_flags & ZFS_XATTR) {
zfs_rmnode(zp);
} else {
mutex_enter(&zfsvfs->z_delete_head.z_mutex);
list_insert_tail(&zfsvfs->z_delete_head.z_znodes, zp);
zfsvfs->z_delete_head.z_znode_count++;
cv_broadcast(&zfsvfs->z_delete_head.z_cv);
mutex_exit(&zfsvfs->z_delete_head.z_mutex);
}
VFS_RELE(zfsvfs->z_vfs);
return;
}
/*
* If the file system for this znode is no longer mounted,
* evict the znode now, don't put it in the cache.
*/
if (zfsvfs->z_unmounted1) {
zfs_zcache_evict(zp, ZFS_OBJ_MUTEX(zp));
return;
}
/* put znode on evictable list */
mutex_enter(&zp->z_zcache_state->mtx);
list_insert_head(&zp->z_zcache_state->list, zp);
zp->z_zcache_state->lcnt += 1;
mutex_exit(&zp->z_zcache_state->mtx);
mutex_exit(&zp->z_lock);
ZFS_OBJ_HOLD_EXIT(zfsvfs, z_id);
}
void
zfs_znode_free(znode_t *zp)
{
zfsvfs_t *zfsvfs = zp->z_zfsvfs;
mutex_enter(&zfsvfs->z_znodes_lock);
list_remove(&zfsvfs->z_all_znodes, zp);
mutex_exit(&zfsvfs->z_znodes_lock);
kmem_cache_free(znode_cache, zp);
}
void
zfs_time_stamper_locked(znode_t *zp, uint_t flag, dmu_tx_t *tx)
{
timestruc_t now;
ASSERT(MUTEX_HELD(&zp->z_lock));
gethrestime(&now);
if (tx) {
dmu_buf_will_dirty(zp->z_dbuf, tx);
zp->z_atime_dirty = 0;
zp->z_seq++;
} else {
zp->z_atime_dirty = 1;
}
if (flag & AT_ATIME)
ZFS_TIME_ENCODE(&now, zp->z_phys->zp_atime);
if (flag & AT_MTIME)
ZFS_TIME_ENCODE(&now, zp->z_phys->zp_mtime);
if (flag & AT_CTIME)
ZFS_TIME_ENCODE(&now, zp->z_phys->zp_ctime);
}
/*
* Update the requested znode timestamps with the current time.
* If we are in a transaction, then go ahead and mark the znode
* dirty in the transaction so the timestamps will go to disk.
* Otherwise, we will get pushed next time the znode is updated
* in a transaction, or when this znode eventually goes inactive.
*
* Why is this OK?
* 1 - Only the ACCESS time is ever updated outside of a transaction.
* 2 - Multiple consecutive updates will be collapsed into a single
* znode update by the transaction grouping semantics of the DMU.
*/
void
zfs_time_stamper(znode_t *zp, uint_t flag, dmu_tx_t *tx)
{
mutex_enter(&zp->z_lock);
zfs_time_stamper_locked(zp, flag, tx);
mutex_exit(&zp->z_lock);
}
/*
* Grow the block size for a file. This may involve migrating data
* from the bonus buffer into a data block (when we grow beyond the
* bonus buffer data area).
*
* IN: zp - znode of file to free data in.
* size - requested block size
* tx - open transaction.
*
* RETURN: 0 if success
* error code if failure
*
* NOTE: this function assumes that the znode is write locked.
*/
int
zfs_grow_blocksize(znode_t *zp, uint64_t size, dmu_tx_t *tx)
{
int error;
u_longlong_t dummy;
ASSERT(rw_write_held(&zp->z_grow_lock));
if (size <= zp->z_blksz)
return (0);
/*
* If the file size is already greater than the current blocksize,
* we will not grow. If there is more than one block in a file,
* the blocksize cannot change.
*/
if (zp->z_blksz && zp->z_phys->zp_size > zp->z_blksz)
return (0);
error = dmu_object_set_blocksize(zp->z_zfsvfs->z_os, zp->z_id,
size, 0, tx);
if (error == ENOTSUP)
return (0);
ASSERT3U(error, ==, 0);
/* What blocksize did we actually get? */
dmu_object_size_from_db(zp->z_dbuf, &zp->z_blksz, &dummy);
return (0);
}
/*
* This is a dummy interface used when pvn_vplist_dirty() should *not*
* be calling back into the fs for a putpage(). E.g.: when truncating
* a file, the pages being "thrown away* don't need to be written out.
*/
/* ARGSUSED */
static int
zfs_no_putpage(vnode_t *vp, page_t *pp, u_offset_t *offp, size_t *lenp,
int flags, cred_t *cr)
{
ASSERT(0);
return (0);
}
/*
* Free space in a file. Currently, this function only
* supports freeing space at the end of the file.
*
* IN: zp - znode of file to free data in.
* from - start of section to free.
* len - length of section to free (0 => to EOF).
* flag - current file open mode flags.
* tx - open transaction.
*
* RETURN: 0 if success
* error code if failure
*/
int
zfs_freesp(znode_t *zp, uint64_t from, uint64_t len, int flag, dmu_tx_t *tx,
cred_t *cr)
{
vnode_t *vp = ZTOV(zp);
uint64_t size = zp->z_phys->zp_size;
uint64_t end = from + len;
int have_grow_lock, error;
have_grow_lock = RW_WRITE_HELD(&zp->z_grow_lock);
/*
* Nothing to do if file already at desired length.
*/
if (len == 0 && size == from) {
return (0);
}
/*
* Check for any locks in the region to be freed.
*/
if (MANDLOCK(vp, (mode_t)zp->z_phys->zp_mode)) {
uint64_t start;
if (size > from)
start = from;
else
start = size;
if (error = chklock(vp, FWRITE, start, 0, flag, NULL))
return (error);
}
if (end > zp->z_blksz && (!ISP2(zp->z_blksz) ||
zp->z_blksz < zp->z_zfsvfs->z_max_blksz)) {
uint64_t new_blksz;
/*
* We are growing the file past the current block size.
*/
if (zp->z_blksz > zp->z_zfsvfs->z_max_blksz) {
ASSERT(!ISP2(zp->z_blksz));
new_blksz = MIN(end, SPA_MAXBLOCKSIZE);
} else {
new_blksz = MIN(end, zp->z_zfsvfs->z_max_blksz);
}
error = zfs_grow_blocksize(zp, new_blksz, tx);
ASSERT(error == 0);
}
if (end > size || len == 0)
zp->z_phys->zp_size = end;
if (from > size)
return (0);
if (have_grow_lock)
rw_downgrade(&zp->z_grow_lock);
/*
* Clear any mapped pages in the truncated region.
*/
rw_enter(&zp->z_map_lock, RW_WRITER);
if (vn_has_cached_data(vp)) {
page_t *pp;
uint64_t start = from & PAGEMASK;
int off = from & PAGEOFFSET;
if (off != 0 && (pp = page_lookup(vp, start, SE_SHARED))) {
/*
* We need to zero a partial page.
*/
pagezero(pp, off, PAGESIZE - off);
start += PAGESIZE;
page_unlock(pp);
}
error = pvn_vplist_dirty(vp, start, zfs_no_putpage,
B_INVAL | B_TRUNC, cr);
ASSERT(error == 0);
}
rw_exit(&zp->z_map_lock);
if (!have_grow_lock)
rw_enter(&zp->z_grow_lock, RW_READER);
if (len == 0)
len = -1;
else if (end > size)
len = size - from;
dmu_free_range(zp->z_zfsvfs->z_os, zp->z_id, from, len, tx);
if (!have_grow_lock)
rw_exit(&zp->z_grow_lock);
return (0);
}
void
zfs_create_fs(objset_t *os, cred_t *cr, dmu_tx_t *tx)
{
zfsvfs_t zfsvfs;
uint64_t moid, doid, roid = 0;
uint64_t version = ZFS_VERSION;
int error;
znode_t *rootzp = NULL;
vnode_t *vp;
vattr_t vattr;
/*
* First attempt to create master node.
*/
moid = MASTER_NODE_OBJ;
error = zap_create_claim(os, moid, DMU_OT_MASTER_NODE,
DMU_OT_NONE, 0, tx);
ASSERT(error == 0);
/*
* Set starting attributes.
*/
error = zap_update(os, moid, ZFS_VERSION_OBJ, 8, 1, &version, tx);
ASSERT(error == 0);
/*
* Create a delete queue.
*/
doid = zap_create(os, DMU_OT_DELETE_QUEUE, DMU_OT_NONE, 0, tx);
error = zap_add(os, moid, ZFS_DELETE_QUEUE, 8, 1, &doid, tx);
ASSERT(error == 0);
/*
* Create root znode. Create minimal znode/vnode/zfsvfs
* to allow zfs_mknode to work.
*/
vattr.va_mask = AT_MODE|AT_UID|AT_GID|AT_TYPE;
vattr.va_type = VDIR;
vattr.va_mode = S_IFDIR|0755;
vattr.va_uid = 0;
vattr.va_gid = 3;
rootzp = kmem_cache_alloc(znode_cache, KM_SLEEP);
rootzp->z_zfsvfs = &zfsvfs;
rootzp->z_active = 1;
rootzp->z_reap = 0;
rootzp->z_atime_dirty = 0;
rootzp->z_dbuf_held = 0;
vp = ZTOV(rootzp);
vn_reinit(vp);
vp->v_type = VDIR;
bzero(&zfsvfs, sizeof (zfsvfs_t));
zfsvfs.z_os = os;
zfsvfs.z_assign = TXG_NOWAIT;
zfsvfs.z_parent = &zfsvfs;
mutex_init(&zfsvfs.z_znodes_lock, NULL, MUTEX_DEFAULT, NULL);
list_create(&zfsvfs.z_all_znodes, sizeof (znode_t),
offsetof(znode_t, z_link_node));
zfs_mknode(rootzp, &vattr, &roid, tx, cr, IS_ROOT_NODE, NULL, 0);
ASSERT3U(rootzp->z_id, ==, roid);
error = zap_add(os, moid, ZFS_ROOT_OBJ, 8, 1, &roid, tx);
ASSERT(error == 0);
ZTOV(rootzp)->v_count = 0;
kmem_cache_free(znode_cache, rootzp);
}