root/usr/src/uts/common/fs/zfs/zfs_sa.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 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 (c) 2010, Oracle and/or its affiliates. All rights reserved.
 */

#include <sys/zfs_context.h>
#include <sys/vnode.h>
#include <sys/sa.h>
#include <sys/zfs_acl.h>
#include <sys/zfs_sa.h>
#include <sys/dmu_objset.h>
#include <sys/sa_impl.h>

/*
 * ZPL attribute registration table.
 * Order of attributes doesn't matter
 * a unique value will be assigned for each
 * attribute that is file system specific
 *
 * This is just the set of ZPL attributes that this
 * version of ZFS deals with natively.  The file system
 * could have other attributes stored in files, but they will be
 * ignored.  The SA framework will preserve them, just that
 * this version of ZFS won't change or delete them.
 */

sa_attr_reg_t zfs_attr_table[ZPL_END+1] = {
        {"ZPL_ATIME", sizeof (uint64_t) * 2, SA_UINT64_ARRAY, 0},
        {"ZPL_MTIME", sizeof (uint64_t) * 2, SA_UINT64_ARRAY, 1},
        {"ZPL_CTIME", sizeof (uint64_t) * 2, SA_UINT64_ARRAY, 2},
        {"ZPL_CRTIME", sizeof (uint64_t) * 2, SA_UINT64_ARRAY, 3},
        {"ZPL_GEN", sizeof (uint64_t), SA_UINT64_ARRAY, 4},
        {"ZPL_MODE", sizeof (uint64_t), SA_UINT64_ARRAY, 5},
        {"ZPL_SIZE", sizeof (uint64_t), SA_UINT64_ARRAY, 6},
        {"ZPL_PARENT", sizeof (uint64_t), SA_UINT64_ARRAY, 7},
        {"ZPL_LINKS", sizeof (uint64_t), SA_UINT64_ARRAY, 8},
        {"ZPL_XATTR", sizeof (uint64_t), SA_UINT64_ARRAY, 9},
        {"ZPL_RDEV", sizeof (uint64_t), SA_UINT64_ARRAY, 10},
        {"ZPL_FLAGS", sizeof (uint64_t), SA_UINT64_ARRAY, 11},
        {"ZPL_UID", sizeof (uint64_t), SA_UINT64_ARRAY, 12},
        {"ZPL_GID", sizeof (uint64_t), SA_UINT64_ARRAY, 13},
        {"ZPL_PAD", sizeof (uint64_t) * 4, SA_UINT64_ARRAY, 14},
        {"ZPL_ZNODE_ACL", 88, SA_UINT8_ARRAY, 15},
        {"ZPL_DACL_COUNT", sizeof (uint64_t), SA_UINT64_ARRAY, 0},
        {"ZPL_SYMLINK", 0, SA_UINT8_ARRAY, 0},
        {"ZPL_SCANSTAMP", 32, SA_UINT8_ARRAY, 0},
        {"ZPL_DACL_ACES", 0, SA_ACL, 0},
        {"ZPL_PROJID", sizeof (uint64_t), SA_UINT64_ARRAY, 0},
        {NULL, 0, 0, 0}
};

#ifdef _KERNEL

int
zfs_sa_readlink(znode_t *zp, uio_t *uio)
{
        dmu_buf_t *db = sa_get_db(zp->z_sa_hdl);
        size_t bufsz;
        int error;

        bufsz = zp->z_size;
        if (bufsz + ZFS_OLD_ZNODE_PHYS_SIZE <= db->db_size) {
                error = uiomove((caddr_t)db->db_data +
                    ZFS_OLD_ZNODE_PHYS_SIZE,
                    MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio);
        } else {
                dmu_buf_t *dbp;
                if ((error = dmu_buf_hold(zp->z_zfsvfs->z_os, zp->z_id,
                    0, FTAG, &dbp, DMU_READ_NO_PREFETCH)) == 0) {
                        error = uiomove(dbp->db_data,
                            MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio);
                        dmu_buf_rele(dbp, FTAG);
                }
        }
        return (error);
}

void
zfs_sa_symlink(znode_t *zp, char *link, int len, dmu_tx_t *tx)
{
        dmu_buf_t *db = sa_get_db(zp->z_sa_hdl);

        if (ZFS_OLD_ZNODE_PHYS_SIZE + len <= dmu_bonus_max()) {
                VERIFY0(dmu_set_bonus(db, len + ZFS_OLD_ZNODE_PHYS_SIZE, tx));
                if (len) {
                        bcopy(link, (caddr_t)db->db_data +
                            ZFS_OLD_ZNODE_PHYS_SIZE, len);
                }
        } else {
                dmu_buf_t *dbp;

                zfs_grow_blocksize(zp, len, tx);
                VERIFY(0 == dmu_buf_hold(zp->z_zfsvfs->z_os,
                    zp->z_id, 0, FTAG, &dbp, DMU_READ_NO_PREFETCH));

                dmu_buf_will_dirty(dbp, tx);

                ASSERT3U(len, <=, dbp->db_size);
                bcopy(link, dbp->db_data, len);
                dmu_buf_rele(dbp, FTAG);
        }
}

void
zfs_sa_get_scanstamp(znode_t *zp, xvattr_t *xvap)
{
        zfsvfs_t *zfsvfs = zp->z_zfsvfs;
        xoptattr_t *xoap;

        ASSERT(MUTEX_HELD(&zp->z_lock));
        VERIFY((xoap = xva_getxoptattr(xvap)) != NULL);
        if (zp->z_is_sa) {
                if (sa_lookup(zp->z_sa_hdl, SA_ZPL_SCANSTAMP(zfsvfs),
                    &xoap->xoa_av_scanstamp,
                    sizeof (xoap->xoa_av_scanstamp)) != 0)
                        return;
        } else {
                dmu_object_info_t doi;
                dmu_buf_t *db = sa_get_db(zp->z_sa_hdl);
                int len;

                if (!(zp->z_pflags & ZFS_BONUS_SCANSTAMP))
                        return;

                sa_object_info(zp->z_sa_hdl, &doi);
                len = sizeof (xoap->xoa_av_scanstamp) +
                    ZFS_OLD_ZNODE_PHYS_SIZE;

                if (len <= doi.doi_bonus_size) {
                        (void) memcpy(xoap->xoa_av_scanstamp,
                            (caddr_t)db->db_data + ZFS_OLD_ZNODE_PHYS_SIZE,
                            sizeof (xoap->xoa_av_scanstamp));
                }
        }
        XVA_SET_RTN(xvap, XAT_AV_SCANSTAMP);
}

void
zfs_sa_set_scanstamp(znode_t *zp, xvattr_t *xvap, dmu_tx_t *tx)
{
        zfsvfs_t *zfsvfs = zp->z_zfsvfs;
        xoptattr_t *xoap;

        ASSERT(MUTEX_HELD(&zp->z_lock));
        VERIFY((xoap = xva_getxoptattr(xvap)) != NULL);
        if (zp->z_is_sa)
                VERIFY(0 == sa_update(zp->z_sa_hdl, SA_ZPL_SCANSTAMP(zfsvfs),
                    &xoap->xoa_av_scanstamp,
                    sizeof (xoap->xoa_av_scanstamp), tx));
        else {
                dmu_object_info_t doi;
                dmu_buf_t *db = sa_get_db(zp->z_sa_hdl);
                int len;

                sa_object_info(zp->z_sa_hdl, &doi);
                len = sizeof (xoap->xoa_av_scanstamp) +
                    ZFS_OLD_ZNODE_PHYS_SIZE;
                if (len > doi.doi_bonus_size)
                        VERIFY(dmu_set_bonus(db, len, tx) == 0);
                (void) memcpy((caddr_t)db->db_data + ZFS_OLD_ZNODE_PHYS_SIZE,
                    xoap->xoa_av_scanstamp, sizeof (xoap->xoa_av_scanstamp));

                zp->z_pflags |= ZFS_BONUS_SCANSTAMP;
                VERIFY(0 == sa_update(zp->z_sa_hdl, SA_ZPL_FLAGS(zfsvfs),
                    &zp->z_pflags, sizeof (uint64_t), tx));
        }
}

/*
 * I'm not convinced we should do any of this upgrade.
 * since the SA code can read both old/new znode formats
 * with probably little to no performance difference.
 *
 * All new files will be created with the new format.
 */

void
zfs_sa_upgrade(sa_handle_t *hdl, dmu_tx_t *tx)
{
        dmu_buf_t *db = sa_get_db(hdl);
        znode_t *zp = sa_get_userdata(hdl);
        zfsvfs_t *zfsvfs = zp->z_zfsvfs;
        sa_bulk_attr_t bulk[22];
        int count = 0;
        sa_bulk_attr_t sa_attrs[20] = { 0 };
        zfs_acl_locator_cb_t locate = { 0 };
        uint64_t uid, gid, mode, rdev, xattr, parent;
        uint64_t crtime[2], mtime[2], ctime[2];
        zfs_acl_phys_t znode_acl;
        char scanstamp[AV_SCANSTAMP_SZ];
        boolean_t drop_lock = B_FALSE;

        /*
         * No upgrade if ACL isn't cached
         * since we won't know which locks are held
         * and ready the ACL would require special "locked"
         * interfaces that would be messy
         */
        if (zp->z_acl_cached == NULL || ZTOV(zp)->v_type == VLNK)
                return;

        /*
         * If the z_lock is held and we aren't the owner
         * the just return since we don't want to deadlock
         * trying to update the status of z_is_sa.  This
         * file can then be upgraded at a later time.
         *
         * Otherwise, we know we are doing the
         * sa_update() that caused us to enter this function.
         */
        if (mutex_owner(&zp->z_lock) != curthread) {
                if (mutex_tryenter(&zp->z_lock) == 0)
                        return;
                else
                        drop_lock = B_TRUE;
        }

        /* First do a bulk query of the attributes that aren't cached */
        SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MTIME(zfsvfs), NULL, &mtime, 16);
        SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CTIME(zfsvfs), NULL, &ctime, 16);
        SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_CRTIME(zfsvfs), NULL, &crtime, 16);
        SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_MODE(zfsvfs), NULL, &mode, 8);
        SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_PARENT(zfsvfs), NULL, &parent, 8);
        SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_XATTR(zfsvfs), NULL, &xattr, 8);
        SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_RDEV(zfsvfs), NULL, &rdev, 8);
        SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_UID(zfsvfs), NULL, &uid, 8);
        SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_GID(zfsvfs), NULL, &gid, 8);
        SA_ADD_BULK_ATTR(bulk, count, SA_ZPL_ZNODE_ACL(zfsvfs), NULL,
            &znode_acl, 88);

        if (sa_bulk_lookup_locked(hdl, bulk, count) != 0)
                goto done;

        if (dmu_objset_projectquota_enabled(hdl->sa_os) &&
            !(zp->z_pflags & ZFS_PROJID)) {
                zp->z_pflags |= ZFS_PROJID;
                zp->z_projid = ZFS_DEFAULT_PROJID;
        }

        /*
         * While the order here doesn't matter its best to try and organize
         * it is such a way to pick up an already existing layout number
         */
        count = 0;
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_MODE(zfsvfs), NULL, &mode, 8);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_SIZE(zfsvfs), NULL,
            &zp->z_size, 8);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_GEN(zfsvfs),
            NULL, &zp->z_gen, 8);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_UID(zfsvfs), NULL, &uid, 8);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_GID(zfsvfs), NULL, &gid, 8);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_PARENT(zfsvfs),
            NULL, &parent, 8);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_FLAGS(zfsvfs), NULL,
            &zp->z_pflags, 8);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_ATIME(zfsvfs), NULL,
            zp->z_atime, 16);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_MTIME(zfsvfs), NULL,
            &mtime, 16);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_CTIME(zfsvfs), NULL,
            &ctime, 16);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_CRTIME(zfsvfs), NULL,
            &crtime, 16);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_LINKS(zfsvfs), NULL,
            &zp->z_links, 8);
        if (dmu_objset_projectquota_enabled(hdl->sa_os))
                SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_PROJID(zfsvfs), NULL,
                    &zp->z_projid, 8);
        if (zp->z_vnode->v_type == VBLK || zp->z_vnode->v_type == VCHR)
                SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_RDEV(zfsvfs), NULL,
                    &rdev, 8);
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_DACL_COUNT(zfsvfs), NULL,
            &zp->z_acl_cached->z_acl_count, 8);

        if (zp->z_acl_cached->z_version < ZFS_ACL_VERSION_FUID)
                zfs_acl_xform(zp, zp->z_acl_cached, CRED());

        locate.cb_aclp = zp->z_acl_cached;
        SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_DACL_ACES(zfsvfs),
            zfs_acl_data_locator, &locate, zp->z_acl_cached->z_acl_bytes);

        if (xattr)
                SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_XATTR(zfsvfs),
                    NULL, &xattr, 8);

        /* if scanstamp then add scanstamp */

        if (zp->z_pflags & ZFS_BONUS_SCANSTAMP) {
                bcopy((caddr_t)db->db_data + ZFS_OLD_ZNODE_PHYS_SIZE,
                    scanstamp, AV_SCANSTAMP_SZ);
                SA_ADD_BULK_ATTR(sa_attrs, count, SA_ZPL_SCANSTAMP(zfsvfs),
                    NULL, scanstamp, AV_SCANSTAMP_SZ);
                zp->z_pflags &= ~ZFS_BONUS_SCANSTAMP;
        }

        VERIFY(dmu_set_bonustype(db, DMU_OT_SA, tx) == 0);
        VERIFY(sa_replace_all_by_template_locked(hdl, sa_attrs,
            count, tx) == 0);
        if (znode_acl.z_acl_extern_obj)
                VERIFY(0 == dmu_object_free(zfsvfs->z_os,
                    znode_acl.z_acl_extern_obj, tx));

        zp->z_is_sa = B_TRUE;
done:
        if (drop_lock)
                mutex_exit(&zp->z_lock);
}

void
zfs_sa_upgrade_txholds(dmu_tx_t *tx, znode_t *zp)
{
        if (!zp->z_zfsvfs->z_use_sa || zp->z_is_sa)
                return;


        dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_TRUE);

        if (zfs_external_acl(zp)) {
                dmu_tx_hold_free(tx, zfs_external_acl(zp), 0,
                    DMU_OBJECT_END);
        }
}

#endif