diff options
Diffstat (limited to 'sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c')
| -rw-r--r-- | sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c | 3227 |
1 files changed, 3227 insertions, 0 deletions
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c new file mode 100644 index 0000000..6769177 --- /dev/null +++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c @@ -0,0 +1,3227 @@ +/* + * 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 2007 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/vfs.h> +#include <sys/vnode.h> +#include <sys/file.h> +#include <sys/stat.h> +#include <sys/kmem.h> +#include <sys/taskq.h> +#include <sys/uio.h> +#include <sys/atomic.h> +#include <sys/namei.h> +#include <sys/mman.h> +#include <sys/cmn_err.h> +#include <sys/errno.h> +#include <sys/unistd.h> +#include <sys/zfs_vfsops.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/spa.h> +#include <sys/txg.h> +#include <sys/dbuf.h> +#include <sys/zap.h> +#include <sys/dirent.h> +#include <sys/filio.h> +#include <sys/zfs_ctldir.h> +#include <sys/dnlc.h> +#include <sys/zfs_rlock.h> +#include <sys/bio.h> +#include <sys/buf.h> +#include <sys/sf_buf.h> +#include <sys/sched.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 the the intent log to commit if it's is a synchronous operation. + * Morover, 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. + * + * (2) VN_RELE() 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. + * + * (3) All range locks must be grabbed before calling dmu_tx_assign(), + * as they can span dmu_tx_assign() calls. + * + * (4) Always pass zfsvfs->z_assign as the second argument to dmu_tx_assign(). + * In normal operation, this will be TXG_NOWAIT. During ZIL replay, + * it will be a specific txg. Either way, dmu_tx_assign() never blocks. + * This is critical because we don't want to block while holding locks. + * 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. + * + * (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. + * + * (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, seq, 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 VN_HOLD()) + * 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, zfsvfs->z_assign); // try to assign + * if (error) { + * rw_exit(...); // drop locks + * zfs_dirent_unlock(dl); // unlock directory entry + * VN_RELE(...); // release held vnodes + * if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { + * 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 + * VN_RELE(...); // release held vnodes + * zil_commit(zilog, seq, foid); // synchronous when necessary + * ZFS_EXIT(zfsvfs); // finished in zfs + * return (error); // done, report error + */ +/* ARGSUSED */ +static int +zfs_open(ap) + struct vop_open_args /* { + struct vnode *a_vp; + int a_mode; + struct ucred *a_cred; + struct thread *a_td; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + znode_t *zp = VTOZ(vp); + int flag = ap->a_mode; + + /* Keep a count of the synchronous opens in the znode */ + if (flag & FFSYNC) { + atomic_inc_32(&zp->z_sync_cnt); + ZFS_LOG(0, "Unexpected code path, report to pjd@FreeBSD.org"); + } + + vnode_create_vobject(vp, zp->z_phys->zp_size, ap->a_td); + return (0); +} + +/* ARGSUSED */ +static int +zfs_close(ap) + struct vop_close_args /* { + struct vnode *a_vp; + int a_fflag; + struct ucred *a_cred; + struct thread *a_td; + } */ *ap; +{ + znode_t *zp = VTOZ(ap->a_vp); + int flag = ap->a_fflag; + + /* Decrement the synchronous opens in the znode */ + if (flag & FFSYNC) { + atomic_dec_32(&zp->z_sync_cnt); + ZFS_LOG(0, "Unexpected code path, report to pjd@FreeBSD.org"); + } + + return (0); +} + +/* + * Lseek support for finding holes (cmd == _FIO_SEEK_HOLE) and + * data (cmd == _FIO_SEEK_DATA). "off" is an in/out parameter. + */ +static int +zfs_holey(vnode_t *vp, int cmd, offset_t *off) +{ + znode_t *zp = VTOZ(vp); + uint64_t noff = (uint64_t)*off; /* new offset */ + uint64_t file_sz; + int error; + boolean_t hole; + + file_sz = zp->z_phys->zp_size; + if (noff >= file_sz) { + return (ENXIO); + } + + if (cmd == FIOSEEKHOLE) + hole = B_TRUE; + else + hole = B_FALSE; + + error = dmu_offset_next(zp->z_zfsvfs->z_os, zp->z_id, hole, &noff); + + /* end of file? */ + if ((error == ESRCH) || (noff > file_sz)) { + /* + * Handle the virtual hole at the end of file. + */ + if (hole) { + *off = file_sz; + return (0); + } + return (ENXIO); + } + + if (noff < *off) + return (error); + *off = noff; + return (error); +} + +/* ARGSUSED */ +static int +zfs_ioctl(ap) + struct vop_ioctl_args /* { + struct vnode *a_vp; + u_long a_command; + caddr_t a_data; + int fflag; + struct ucred *cred; + struct thread *td; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + int com = ap->a_command; + caddr_t data = ap->a_data; + offset_t off; + zfsvfs_t *zfsvfs; + int error; + + switch (com) { + case FIOSEEKDATA: + case FIOSEEKHOLE: + off = *(offset_t *)data; + + zfsvfs = VTOZ(vp)->z_zfsvfs; + ZFS_ENTER(zfsvfs); + + /* offset parameter is in/out */ + error = zfs_holey(vp, com, &off); + ZFS_EXIT(zfsvfs); + if (error) + return (error); + *(offset_t *)data = off; + return (0); + } + return (ENOTTY); +} + +/* + * When a file is memory mapped, we must keep the IO data synchronized + * between the DMU cache and the memory mapped pages. What this means: + * + * On Write: If we find a memory mapped page, we write to *both* + * the page and the dmu buffer. + * + * NOTE: We will always "break up" the IO into PAGESIZE uiomoves when + * the file is memory mapped. + */ +static int +mappedwrite(vnode_t *vp, int nbytes, uio_t *uio, dmu_tx_t *tx) +{ + znode_t *zp = VTOZ(vp); + objset_t *os = zp->z_zfsvfs->z_os; + vm_object_t obj; + vm_page_t m; + struct sf_buf *sf; + int64_t start, off; + int len = nbytes; + int error = 0; + + ASSERT(vp->v_mount != NULL); + obj = vp->v_object; + ASSERT(obj != NULL); + + start = uio->uio_loffset; + off = start & PAGEOFFSET; + VM_OBJECT_LOCK(obj); + for (start &= PAGEMASK; len > 0; start += PAGESIZE) { + uint64_t bytes = MIN(PAGESIZE - off, len); + uint64_t woff = uio->uio_loffset; + +again: + if ((m = vm_page_lookup(obj, OFF_TO_IDX(start))) != NULL && + vm_page_is_valid(m, (vm_offset_t)off, bytes)) { + caddr_t va; + + if (vm_page_sleep_if_busy(m, FALSE, "zfsmwb")) + goto again; + vm_page_busy(m); + VM_OBJECT_UNLOCK(obj); + sched_pin(); + sf = sf_buf_alloc(m, SFB_CPUPRIVATE); + va = (caddr_t)sf_buf_kva(sf); + error = uiomove(va+off, bytes, UIO_WRITE, uio); + if (error == 0) + dmu_write(os, zp->z_id, woff, bytes, va+off, tx); + sf_buf_free(sf); + sched_unpin(); + VM_OBJECT_LOCK(obj); + vm_page_wakeup(m); + } else { + VM_OBJECT_UNLOCK(obj); + error = dmu_write_uio(os, zp->z_id, uio, bytes, tx); + VM_OBJECT_LOCK(obj); + } + len -= bytes; + off = 0; + if (error) + break; + } + VM_OBJECT_UNLOCK(obj); + return (error); +} + +/* + * When a file is memory mapped, we must keep the IO data synchronized + * between the DMU cache and the memory mapped pages. What this means: + * + * On Read: We "read" preferentially from memory mapped pages, + * else we default from the dmu buffer. + * + * NOTE: We will always "break up" the IO into PAGESIZE uiomoves when + * the file is memory mapped. + */ +static int +mappedread(vnode_t *vp, int nbytes, uio_t *uio) +{ + znode_t *zp = VTOZ(vp); + objset_t *os = zp->z_zfsvfs->z_os; + vm_object_t obj; + vm_page_t m; + struct sf_buf *sf; + int64_t start, off; + int len = nbytes; + int error = 0; + + ASSERT(vp->v_mount != NULL); + obj = vp->v_object; + ASSERT(obj != NULL); + + start = uio->uio_loffset; + off = start & PAGEOFFSET; + VM_OBJECT_LOCK(obj); + for (start &= PAGEMASK; len > 0; start += PAGESIZE) { + uint64_t bytes = MIN(PAGESIZE - off, len); + +again: + if ((m = vm_page_lookup(obj, OFF_TO_IDX(start))) != NULL && + vm_page_is_valid(m, (vm_offset_t)off, bytes)) { + caddr_t va; + + if (vm_page_sleep_if_busy(m, FALSE, "zfsmrb")) + goto again; + vm_page_busy(m); + VM_OBJECT_UNLOCK(obj); + sched_pin(); + sf = sf_buf_alloc(m, SFB_CPUPRIVATE); + va = (caddr_t)sf_buf_kva(sf); + error = uiomove(va + off, bytes, UIO_READ, uio); + sf_buf_free(sf); + sched_unpin(); + VM_OBJECT_LOCK(obj); + vm_page_wakeup(m); + } else { + VM_OBJECT_UNLOCK(obj); + error = dmu_read_uio(os, zp->z_id, uio, bytes); + VM_OBJECT_LOCK(obj); + } + len -= bytes; + off = 0; + if (error) + break; + } + VM_OBJECT_UNLOCK(obj); + return (error); +} + +offset_t zfs_read_chunk_size = 1024 * 1024; /* Tunable */ + +/* + * Read bytes from specified file into supplied buffer. + * + * IN: vp - vnode of file to be read from. + * uio - structure supplying read location, range info, + * and return buffer. + * ioflag - SYNC flags; used to provide FRSYNC semantics. + * cr - credentials of caller. + * + * OUT: uio - updated offset and range, buffer filled. + * + * RETURN: 0 if success + * error code if failure + * + * Side Effects: + * vp - atime updated if byte count > 0 + */ +/* ARGSUSED */ +static int +zfs_read(ap) + struct vop_read_args /* { + struct vnode *a_vp; + struct uio *a_uio; + int a_ioflag; + struct ucred *a_cred; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + uio_t *uio = ap->a_uio; + int ioflag = ap->a_ioflag; + znode_t *zp = VTOZ(vp); + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + objset_t *os = zfsvfs->z_os; + ssize_t n, nbytes; + int error; + rl_t *rl; + + ZFS_ENTER(zfsvfs); + + /* + * Validate file offset + */ + if (uio->uio_loffset < (offset_t)0) { + ZFS_EXIT(zfsvfs); + return (EINVAL); + } + + /* + * Fasttrack empty reads + */ + if (uio->uio_resid == 0) { + ZFS_EXIT(zfsvfs); + return (0); + } + + /* + * If we're in FRSYNC mode, sync out this znode before reading it. + */ + if (ioflag & IO_SYNC) + zil_commit(zfsvfs->z_log, zp->z_last_itx, zp->z_id); + + /* + * Lock the range against changes. + */ + rl = zfs_range_lock(zp, uio->uio_loffset, uio->uio_resid, RL_READER); + + /* + * If we are reading past end-of-file we can skip + * to the end; but we might still need to set atime. + */ + if (uio->uio_loffset >= zp->z_phys->zp_size) { + error = 0; + goto out; + } + + ASSERT(uio->uio_loffset < zp->z_phys->zp_size); + n = MIN(uio->uio_resid, zp->z_phys->zp_size - uio->uio_loffset); + + while (n > 0) { + nbytes = MIN(n, zfs_read_chunk_size - + P2PHASE(uio->uio_loffset, zfs_read_chunk_size)); + + if (vn_has_cached_data(vp)) + error = mappedread(vp, nbytes, uio); + else + error = dmu_read_uio(os, zp->z_id, uio, nbytes); + if (error) + break; + n -= nbytes; + } + +out: + zfs_range_unlock(rl); + + ZFS_ACCESSTIME_STAMP(zfsvfs, zp); + ZFS_EXIT(zfsvfs); + + return (error); +} + +/* + * Fault in the pages of the first n bytes specified by the uio structure. + * 1 byte in each page is touched and the uio struct is unmodified. + * Any error will exit this routine as this is only a best + * attempt to get the pages resident. This is a copy of ufs_trans_touch(). + */ +static void +zfs_prefault_write(ssize_t n, struct uio *uio) +{ + struct iovec *iov; + ulong_t cnt, incr; + caddr_t p; + + if (uio->uio_segflg != UIO_USERSPACE) + return; + + iov = uio->uio_iov; + + while (n) { + cnt = MIN(iov->iov_len, n); + if (cnt == 0) { + /* empty iov entry */ + iov++; + continue; + } + n -= cnt; + /* + * touch each page in this segment. + */ + p = iov->iov_base; + while (cnt) { + if (fubyte(p) == -1) + return; + incr = MIN(cnt, PAGESIZE); + p += incr; + cnt -= incr; + } + /* + * touch the last byte in case it straddles a page. + */ + p--; + if (fubyte(p) == -1) + return; + iov++; + } +} + +/* + * Write the bytes to a file. + * + * IN: vp - vnode of file to be written to. + * uio - structure supplying write location, range info, + * and data buffer. + * ioflag - IO_APPEND flag set if in append mode. + * cr - credentials of caller. + * + * OUT: uio - updated offset and range. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * vp - ctime|mtime updated if byte count > 0 + */ +/* ARGSUSED */ +static int +zfs_write(ap) + struct vop_write_args /* { + struct vnode *a_vp; + struct uio *a_uio; + int a_ioflag; + struct ucred *a_cred; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + uio_t *uio = ap->a_uio; + int ioflag = ap->a_ioflag; + cred_t *cr = ap->a_cred; + znode_t *zp = VTOZ(vp); + ssize_t start_resid = uio->uio_resid; + ssize_t tx_bytes; + uint64_t end_size; + dmu_tx_t *tx; + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + zilog_t *zilog = zfsvfs->z_log; + offset_t woff; + ssize_t n, nbytes; + rl_t *rl; + int max_blksz = zfsvfs->z_max_blksz; + int error; + + /* + * Fasttrack empty write + */ + n = start_resid; + if (n == 0) + return (0); + + ZFS_ENTER(zfsvfs); + + /* + * Pre-fault the pages to ensure slow (eg NFS) pages + * don't hold up txg. + */ + zfs_prefault_write(n, uio); + + /* + * If in append mode, set the io offset pointer to eof. + */ + if (ioflag & IO_APPEND) { + /* + * Range lock for a file append: + * The value for the start of range will be determined by + * zfs_range_lock() (to guarantee append semantics). + * If this write will cause the block size to increase, + * zfs_range_lock() will lock the entire file, so we must + * later reduce the range after we grow the block size. + */ + rl = zfs_range_lock(zp, 0, n, RL_APPEND); + if (rl->r_len == UINT64_MAX) { + /* overlocked, zp_size can't change */ + woff = uio->uio_loffset = zp->z_phys->zp_size; + } else { + woff = uio->uio_loffset = rl->r_off; + } + } else { + woff = uio->uio_loffset; + /* + * Validate file offset + */ + if (woff < 0) { + ZFS_EXIT(zfsvfs); + return (EINVAL); + } + + /* + * If we need to grow the block size then zfs_range_lock() + * will lock a wider range than we request here. + * Later after growing the block size we reduce the range. + */ + rl = zfs_range_lock(zp, woff, n, RL_WRITER); + } + + end_size = MAX(zp->z_phys->zp_size, woff + n); + + /* + * Write the file in reasonable size chunks. Each chunk is written + * in a separate transaction; this keeps the intent log records small + * and allows us to do more fine-grained space accounting. + */ + while (n > 0) { + /* + * Start a transaction. + */ + woff = uio->uio_loffset; + tx = dmu_tx_create(zfsvfs->z_os); + dmu_tx_hold_bonus(tx, zp->z_id); + dmu_tx_hold_write(tx, zp->z_id, woff, MIN(n, max_blksz)); + error = dmu_tx_assign(tx, zfsvfs->z_assign); + if (error) { + if (error == ERESTART && + zfsvfs->z_assign == TXG_NOWAIT) { + dmu_tx_wait(tx); + dmu_tx_abort(tx); + continue; + } + dmu_tx_abort(tx); + break; + } + + /* + * If zfs_range_lock() over-locked we grow the blocksize + * and then reduce the lock range. This will only happen + * on the first iteration since zfs_range_reduce() will + * shrink down r_len to the appropriate size. + */ + if (rl->r_len == UINT64_MAX) { + uint64_t new_blksz; + + if (zp->z_blksz > max_blksz) { + ASSERT(!ISP2(zp->z_blksz)); + new_blksz = MIN(end_size, SPA_MAXBLOCKSIZE); + } else { + new_blksz = MIN(end_size, max_blksz); + } + zfs_grow_blocksize(zp, new_blksz, tx); + zfs_range_reduce(rl, woff, n); + } + + /* + * XXX - should we really limit each write to z_max_blksz? + * Perhaps we should use SPA_MAXBLOCKSIZE chunks? + */ + nbytes = MIN(n, max_blksz - P2PHASE(woff, max_blksz)); + rw_enter(&zp->z_map_lock, RW_READER); + + tx_bytes = uio->uio_resid; + if (woff + nbytes > zp->z_phys->zp_size) + vnode_pager_setsize(vp, woff + nbytes); + + if (vn_has_cached_data(vp)) { + rw_exit(&zp->z_map_lock); + error = mappedwrite(vp, nbytes, uio, tx); + } else { + error = dmu_write_uio(zfsvfs->z_os, zp->z_id, + uio, nbytes, tx); + rw_exit(&zp->z_map_lock); + } + tx_bytes -= uio->uio_resid; + + /* + * If we made no progress, we're done. If we made even + * partial progress, update the znode and ZIL accordingly. + */ + if (tx_bytes == 0) { + dmu_tx_commit(tx); + ASSERT(error != 0); + break; + } + + /* + * Clear Set-UID/Set-GID bits on successful write if not + * privileged and at least one of the excute bits is set. + * + * It would be nice to to this after all writes have + * been done, but that would still expose the ISUID/ISGID + * to another app after the partial write is committed. + */ + mutex_enter(&zp->z_acl_lock); + if ((zp->z_phys->zp_mode & (S_IXUSR | (S_IXUSR >> 3) | + (S_IXUSR >> 6))) != 0 && + (zp->z_phys->zp_mode & (S_ISUID | S_ISGID)) != 0 && + secpolicy_vnode_setid_retain(cr, + (zp->z_phys->zp_mode & S_ISUID) != 0 && + zp->z_phys->zp_uid == 0) != 0) { + zp->z_phys->zp_mode &= ~(S_ISUID | S_ISGID); + } + mutex_exit(&zp->z_acl_lock); + + /* + * Update time stamp. NOTE: This marks the bonus buffer as + * dirty, so we don't have to do it again for zp_size. + */ + zfs_time_stamper(zp, CONTENT_MODIFIED, tx); + + /* + * Update the file size (zp_size) if it has changed; + * account for possible concurrent updates. + */ + while ((end_size = zp->z_phys->zp_size) < uio->uio_loffset) + (void) atomic_cas_64(&zp->z_phys->zp_size, end_size, + uio->uio_loffset); + zfs_log_write(zilog, tx, TX_WRITE, zp, woff, tx_bytes, ioflag); + dmu_tx_commit(tx); + + if (error != 0) + break; + ASSERT(tx_bytes == nbytes); + n -= nbytes; + } + + zfs_range_unlock(rl); + + /* + * If we're in replay mode, or we made no progress, return error. + * Otherwise, it's at least a partial write, so it's successful. + */ + if (zfsvfs->z_assign >= TXG_INITIAL || uio->uio_resid == start_resid) { + ZFS_EXIT(zfsvfs); + return (error); + } + + if (ioflag & IO_SYNC) + zil_commit(zilog, zp->z_last_itx, zp->z_id); + + ZFS_EXIT(zfsvfs); + return (0); +} + +void +zfs_get_done(dmu_buf_t *db, void *vzgd) +{ + zgd_t *zgd = (zgd_t *)vzgd; + rl_t *rl = zgd->zgd_rl; + vnode_t *vp = ZTOV(rl->r_zp); + int vfslocked; + + vfslocked = VFS_LOCK_GIANT(vp->v_vfsp); + dmu_buf_rele(db, vzgd); + zfs_range_unlock(rl); + VN_RELE(vp); + zil_add_vdev(zgd->zgd_zilog, DVA_GET_VDEV(BP_IDENTITY(zgd->zgd_bp))); + kmem_free(zgd, sizeof (zgd_t)); + VFS_UNLOCK_GIANT(vfslocked); +} + +/* + * Get data to generate a TX_WRITE intent log record. + */ +int +zfs_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) +{ + zfsvfs_t *zfsvfs = arg; + objset_t *os = zfsvfs->z_os; + znode_t *zp; + uint64_t off = lr->lr_offset; + dmu_buf_t *db; + rl_t *rl; + zgd_t *zgd; + int dlen = lr->lr_length; /* length of user data */ + int error = 0; + + ASSERT(zio); + ASSERT(dlen != 0); + + /* + * Nothing to do if the file has been removed + */ + if (zfs_zget(zfsvfs, lr->lr_foid, &zp) != 0) + return (ENOENT); + if (zp->z_unlinked) { + VN_RELE(ZTOV(zp)); + return (ENOENT); + } + + /* + * Write records come in two flavors: immediate and indirect. + * For small writes it's cheaper to store the data with the + * log record (immediate); for large writes it's cheaper to + * sync the data and get a pointer to it (indirect) so that + * we don't have to write the data twice. + */ + if (buf != NULL) { /* immediate write */ + rl = zfs_range_lock(zp, off, dlen, RL_READER); + /* test for truncation needs to be done while range locked */ + if (off >= zp->z_phys->zp_size) { + error = ENOENT; + goto out; + } + VERIFY(0 == dmu_read(os, lr->lr_foid, off, dlen, buf)); + } else { /* indirect write */ + uint64_t boff; /* block starting offset */ + + /* + * Have to lock the whole block to ensure when it's + * written out and it's checksum is being calculated + * that no one can change the data. We need to re-check + * blocksize after we get the lock in case it's changed! + */ + for (;;) { + if (ISP2(zp->z_blksz)) { + boff = P2ALIGN_TYPED(off, zp->z_blksz, + uint64_t); + } else { + boff = 0; + } + dlen = zp->z_blksz; + rl = zfs_range_lock(zp, boff, dlen, RL_READER); + if (zp->z_blksz == dlen) + break; + zfs_range_unlock(rl); + } + /* test for truncation needs to be done while range locked */ + if (off >= zp->z_phys->zp_size) { + error = ENOENT; + goto out; + } + zgd = (zgd_t *)kmem_alloc(sizeof (zgd_t), KM_SLEEP); + zgd->zgd_rl = rl; + zgd->zgd_zilog = zfsvfs->z_log; + zgd->zgd_bp = &lr->lr_blkptr; + VERIFY(0 == dmu_buf_hold(os, lr->lr_foid, boff, zgd, &db)); + ASSERT(boff == db->db_offset); + lr->lr_blkoff = off - boff; + error = dmu_sync(zio, db, &lr->lr_blkptr, + lr->lr_common.lrc_txg, zfs_get_done, zgd); + ASSERT(error == EEXIST || lr->lr_length <= zp->z_blksz); + if (error == 0) { + zil_add_vdev(zfsvfs->z_log, + DVA_GET_VDEV(BP_IDENTITY(&lr->lr_blkptr))); + } + /* + * If we get EINPROGRESS, then we need to wait for a + * write IO initiated by dmu_sync() to complete before + * we can release this dbuf. We will finish everything + * up in the zfs_get_done() callback. + */ + if (error == EINPROGRESS) + return (0); + dmu_buf_rele(db, zgd); + kmem_free(zgd, sizeof (zgd_t)); + } +out: + zfs_range_unlock(rl); + VN_RELE(ZTOV(zp)); + return (error); +} + +/*ARGSUSED*/ +static int +zfs_access(ap) + struct vop_access_args /* { + struct vnode *a_vp; + int a_mode; + struct ucred *a_cred; + struct thread *a_td; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + znode_t *zp = VTOZ(vp); + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + int error; + + ZFS_ENTER(zfsvfs); + error = zfs_zaccess_rwx(zp, ap->a_mode, ap->a_cred); + ZFS_EXIT(zfsvfs); + return (error); +} + +/* + * Lookup an entry in a directory, or an extended attribute directory. + * If it exists, return a held vnode reference for it. + * + * IN: dvp - vnode of directory to search. + * nm - name of entry to lookup. + * pnp - full pathname to lookup [UNUSED]. + * flags - LOOKUP_XATTR set if looking for an attribute. + * rdir - root directory vnode [UNUSED]. + * cr - credentials of caller. + * + * OUT: vpp - vnode of located entry, NULL if not found. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * NA + */ +/* ARGSUSED */ +int +zfs_lookup(ap) + struct vop_lookup_args /* { + struct vnode *a_dvp; + struct vnode **a_vpp; + struct componentname *a_cnp; + } */ *ap; +{ + kthread_t *td = ap->a_cnp->cn_thread; + struct componentname *cnp = ap->a_cnp; + vnode_t *dvp = ap->a_dvp; + vnode_t **vpp = ap->a_vpp; + u_long flags = cnp->cn_flags; + cred_t *cr = cnp->cn_cred; + int nameiop = cnp->cn_nameiop; + char nm[NAME_MAX + 1]; + znode_t *zdp = VTOZ(dvp); + zfsvfs_t *zfsvfs = zdp->z_zfsvfs; + int error; + + ASSERT(cnp->cn_namelen < sizeof(nm)); + strlcpy(nm, cnp->cn_nameptr, MIN(cnp->cn_namelen + 1, sizeof(nm))); + + ZFS_ENTER(zfsvfs); + + *vpp = NULL; + +#ifdef TODO + if (flags & LOOKUP_XATTR) { + /* + * If the xattr property is off, refuse the lookup request. + */ + if (!(zfsvfs->z_vfs->vfs_flag & VFS_XATTR)) { + ZFS_EXIT(zfsvfs); + return (EINVAL); + } + + /* + * We don't allow recursive attributes.. + * Maybe someday we will. + */ + if (zdp->z_phys->zp_flags & ZFS_XATTR) { + ZFS_EXIT(zfsvfs); + return (EINVAL); + } + + if (error = zfs_get_xattrdir(VTOZ(dvp), vpp, cr, flags)) { + ZFS_EXIT(zfsvfs); + return (error); + } + + /* + * Do we have permission to get into attribute directory? + */ + + if (error = zfs_zaccess(VTOZ(*vpp), ACE_EXECUTE, cr)) { + VN_RELE(*vpp); + } + + ZFS_EXIT(zfsvfs); + return (error); + } +#endif /* TODO */ + + if (dvp->v_type != VDIR) { + ZFS_EXIT(zfsvfs); + return (ENOTDIR); + } + + /* + * Check accessibility of directory. + */ + + if (error = zfs_zaccess(zdp, ACE_EXECUTE, cr)) { + ZFS_EXIT(zfsvfs); + return (error); + } + + error = zfs_dirlook(zdp, nm, vpp); + + ZFS_EXIT(zfsvfs); + + /* Translate errors and add SAVENAME when needed. */ + if (cnp->cn_flags & ISLASTCN) { + switch (nameiop) { + case CREATE: + case RENAME: + if (error == ENOENT) { + error = EJUSTRETURN; + cnp->cn_flags |= SAVENAME; + break; + } + /* FALLTHROUGH */ + case DELETE: + if (error == 0) + cnp->cn_flags |= SAVENAME; + break; + } + } + if (error == 0 && (nm[0] != '.' || nm[1] != '\0')) { + if (flags & ISDOTDOT) + VOP_UNLOCK(dvp, 0, td); + vn_lock(*vpp, LK_EXCLUSIVE | LK_RETRY, td); + if (flags & ISDOTDOT) + vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td); + } + +#ifdef FREEBSD_NAMECACHE + /* + * Insert name into cache (as non-existent) if appropriate. + */ + if (error == ENOENT && (cnp->cn_flags & MAKEENTRY) && nameiop != CREATE) + cache_enter(dvp, *vpp, cnp); + /* + * Insert name into cache if appropriate. + */ + if (error == 0 && (cnp->cn_flags & MAKEENTRY)) { + if (!(cnp->cn_flags & ISLASTCN) || + (nameiop != DELETE && nameiop != RENAME)) { + cache_enter(dvp, *vpp, cnp); + } + } +#endif + + 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 vp of the created or trunc'd file. + * + * IN: dvp - vnode 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 - large file flag [UNUSED]. + * + * OUT: vpp - vnode of created or trunc'd entry. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * dvp - ctime|mtime updated if new entry created + * vp - ctime|mtime always, atime if new + */ +/* ARGSUSED */ +static int +zfs_create(ap) + struct vop_create_args /* { + struct vnode *a_dvp; + struct vnode **a_vpp; + struct componentname *a_cnp; + struct vattr *a_vap; + } */ *ap; +{ + vnode_t *dvp = ap->a_dvp; + vnode_t **vpp = ap->a_vpp; + vattr_t *vap = ap->a_vap; + cred_t *cr = ap->a_cnp->cn_cred; + char *name = ap->a_cnp->cn_nameptr; + znode_t *zp, *dzp = VTOZ(dvp); + zfsvfs_t *zfsvfs = dzp->z_zfsvfs; + zilog_t *zilog = zfsvfs->z_log; + objset_t *os = zfsvfs->z_os; + zfs_dirlock_t *dl; + dmu_tx_t *tx; + int error; + uint64_t zoid; + int mode; + + ASSERT(ap->a_cnp->cn_flags & SAVENAME); + + vattr_init_mask(vap); + mode = vap->va_mode & ALLPERMS; + + ZFS_ENTER(zfsvfs); + +top: + *vpp = NULL; + + if ((vap->va_mode & VSVTX) && secpolicy_vnode_stky_modify(cr)) + vap->va_mode &= ~VSVTX; + + if (*name == '\0') { + /* + * Null component name refers to the directory itself. + */ + VN_HOLD(dvp); + zp = dzp; + dl = NULL; + error = 0; + } else { + /* possible VN_HOLD(zp) */ + if (error = zfs_dirent_lock(&dl, dzp, name, &zp, 0)) { + if (strcmp(name, "..") == 0) + error = EISDIR; + ZFS_EXIT(zfsvfs); + return (error); + } + } + + zoid = zp ? zp->z_id : -1ULL; + + if (zp == NULL) { + /* + * Create a new file object and update the directory + * to reference it. + */ + if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) { + goto out; + } + + /* + * We only support the creation of regular files in + * extended attribute directories. + */ + if ((dzp->z_phys->zp_flags & ZFS_XATTR) && + (vap->va_type != VREG)) { + error = EINVAL; + goto out; + } + + tx = dmu_tx_create(os); + 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, name); + if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) + dmu_tx_hold_write(tx, DMU_NEW_OBJECT, + 0, SPA_MAXBLOCKSIZE); + error = dmu_tx_assign(tx, zfsvfs->z_assign); + if (error) { + zfs_dirent_unlock(dl); + if (error == ERESTART && + zfsvfs->z_assign == TXG_NOWAIT) { + dmu_tx_wait(tx); + dmu_tx_abort(tx); + goto top; + } + dmu_tx_abort(tx); + ZFS_EXIT(zfsvfs); + return (error); + } + zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0); + ASSERT(zp->z_id == zoid); + (void) zfs_link_create(dl, zp, tx, ZNEW); + zfs_log_create(zilog, tx, TX_CREATE, dzp, zp, name); + dmu_tx_commit(tx); + } else { + /* + * A directory entry already exists for this name. + */ + + /* + * Can't open a directory for writing. + */ + if ((ZTOV(zp)->v_type == VDIR) && (mode & S_IWRITE)) { + error = EISDIR; + goto out; + } + /* + * Verify requested access to file. + */ + if (mode && (error = zfs_zaccess_rwx(zp, mode, cr))) { + goto out; + } + + mutex_enter(&dzp->z_lock); + dzp->z_seq++; + mutex_exit(&dzp->z_lock); + + /* + * Truncate regular files if requested. + */ + if ((ZTOV(zp)->v_type == VREG) && + (zp->z_phys->zp_size != 0) && + (vap->va_mask & AT_SIZE) && (vap->va_size == 0)) { + error = zfs_freesp(zp, 0, 0, mode, TRUE); + if (error == ERESTART && + zfsvfs->z_assign == TXG_NOWAIT) { + /* NB: we already did dmu_tx_wait() */ + zfs_dirent_unlock(dl); + VN_RELE(ZTOV(zp)); + goto top; + } + } + } +out: + + if (error == 0) { + *vpp = ZTOV(zp); + vn_lock(*vpp, LK_EXCLUSIVE | LK_RETRY, ap->a_cnp->cn_thread); + } + + if (dl) + zfs_dirent_unlock(dl); + + if (error) { + if (zp) + VN_RELE(ZTOV(zp)); + } + + ZFS_EXIT(zfsvfs); + return (error); +} + +/* + * Remove an entry from a directory. + * + * IN: dvp - vnode of directory to remove entry from. + * name - name of entry to remove. + * cr - credentials of caller. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * dvp - ctime|mtime + * vp - ctime (if nlink > 0) + */ +static int +zfs_remove(ap) + struct vop_remove_args /* { + struct vnode *a_dvp; + struct vnode *a_vp; + struct componentname *a_cnp; + } */ *ap; +{ + vnode_t *dvp = ap->a_dvp; + cred_t *cr = ap->a_cnp->cn_cred; + char *name = ap->a_cnp->cn_nameptr; + znode_t *zp, *dzp = VTOZ(dvp); +#if 0 + znode_t *xzp = NULL; +#endif + vnode_t *vp; + zfsvfs_t *zfsvfs = dzp->z_zfsvfs; + zilog_t *zilog = zfsvfs->z_log; + uint64_t xattr_obj; + zfs_dirlock_t *dl; + dmu_tx_t *tx; + boolean_t unlinked; + int error; + + ASSERT(ap->a_cnp->cn_flags & SAVENAME); + + ZFS_ENTER(zfsvfs); + +top: + /* + * Attempt to lock directory; fail if entry doesn't exist. + */ + if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZEXISTS)) { + ZFS_EXIT(zfsvfs); + return (error); + } + + vp = ZTOV(zp); + ASSERT(vp == ap->a_vp); + ASSERT(vp->v_type != VDIR); + /* Drop an extra reference from zfs_dirent_lock(). */ + VN_RELE(vp); + ASSERT(vp->v_count > 0); + + if (error = zfs_zaccess_delete(dzp, zp, cr)) + goto out; + + dnlc_remove(dvp, name); + + /* + * 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 vnode. So we dmu_tx_hold() the right things to + * allow for either case. + */ + tx = dmu_tx_create(zfsvfs->z_os); + dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name); + dmu_tx_hold_bonus(tx, zp->z_id); + + /* are there any extended attributes? */ + if ((xattr_obj = zp->z_phys->zp_xattr) != 0) { + /* XXX - do we need this if we are deleting? */ + dmu_tx_hold_bonus(tx, xattr_obj); + } + + /* charge as an update -- would be nice not to charge at all */ + dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); + + error = dmu_tx_assign(tx, zfsvfs->z_assign); + if (error) { + zfs_dirent_unlock(dl); + if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { + dmu_tx_wait(tx); + dmu_tx_abort(tx); + goto top; + } + dmu_tx_abort(tx); + ZFS_EXIT(zfsvfs); + return (error); + } + + /* + * Remove the directory entry. + */ + error = zfs_link_destroy(dl, zp, tx, 0, &unlinked); + + if (error) { + dmu_tx_commit(tx); + goto out; + } + + if (unlinked) + zfs_unlinked_add(zp, tx); + + zfs_log_remove(zilog, tx, TX_REMOVE, dzp, name); + + dmu_tx_commit(tx); +out: + zfs_dirent_unlock(dl); + + ZFS_EXIT(zfsvfs); + return (error); +} + +/* + * Create a new directory and insert it into dvp using the name + * provided. Return a pointer to the inserted directory. + * + * IN: dvp - vnode of directory to add subdir to. + * dirname - name of new directory. + * vap - attributes of new directory. + * cr - credentials of caller. + * + * OUT: vpp - vnode of created directory. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * dvp - ctime|mtime updated + * vp - ctime|mtime|atime updated + */ +static int +zfs_mkdir(ap) + struct vop_mkdir_args /* { + struct vnode *a_dvp; + struct vnode **a_vpp; + struct componentname *a_cnp; + struct vattr *a_vap; + } */ *ap; +{ + vnode_t *dvp = ap->a_dvp; + vnode_t **vpp = ap->a_vpp; + vattr_t *vap = ap->a_vap; + cred_t *cr = ap->a_cnp->cn_cred; + char *dirname = ap->a_cnp->cn_nameptr; + znode_t *zp, *dzp = VTOZ(dvp); + zfsvfs_t *zfsvfs = dzp->z_zfsvfs; + zilog_t *zilog = zfsvfs->z_log; + zfs_dirlock_t *dl; + uint64_t zoid = 0; + dmu_tx_t *tx; + int error; + + ASSERT(ap->a_cnp->cn_flags & SAVENAME); + ASSERT(vap->va_type == VDIR); + vattr_init_mask(vap); + + ZFS_ENTER(zfsvfs); + + if (dzp->z_phys->zp_flags & ZFS_XATTR) { + ZFS_EXIT(zfsvfs); + return (EINVAL); + } +top: + *vpp = NULL; + + /* + * First make sure the new directory doesn't exist. + */ + if (error = zfs_dirent_lock(&dl, dzp, dirname, &zp, ZNEW)) { + ZFS_EXIT(zfsvfs); + return (error); + } + + if (error = zfs_zaccess(dzp, ACE_ADD_SUBDIRECTORY, cr)) { + zfs_dirent_unlock(dl); + ZFS_EXIT(zfsvfs); + return (error); + } + + /* + * 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); + if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) + dmu_tx_hold_write(tx, DMU_NEW_OBJECT, + 0, SPA_MAXBLOCKSIZE); + error = dmu_tx_assign(tx, zfsvfs->z_assign); + if (error) { + zfs_dirent_unlock(dl); + if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { + dmu_tx_wait(tx); + dmu_tx_abort(tx); + goto top; + } + dmu_tx_abort(tx); + ZFS_EXIT(zfsvfs); + return (error); + } + + /* + * Create new node. + */ + zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0); + + /* + * Now put new name in parent dir. + */ + (void) zfs_link_create(dl, zp, tx, ZNEW); + + *vpp = ZTOV(zp); + + zfs_log_create(zilog, tx, TX_MKDIR, dzp, zp, dirname); + dmu_tx_commit(tx); + + vn_lock(*vpp, LK_EXCLUSIVE | LK_RETRY, ap->a_cnp->cn_thread); + + zfs_dirent_unlock(dl); + + ZFS_EXIT(zfsvfs); + return (0); +} + +/* + * Remove a directory subdir entry. If the current working + * directory is the same as the subdir to be removed, the + * remove will fail. + * + * IN: dvp - vnode of directory to remove from. + * name - name of directory to be removed. + * cwd - vnode of current working directory. + * cr - credentials of caller. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * dvp - ctime|mtime updated + */ +static int +zfs_rmdir(ap) + struct vop_rmdir_args /* { + struct vnode *a_dvp; + struct vnode *a_vp; + struct componentname *a_cnp; + } */ *ap; +{ + vnode_t *dvp = ap->a_dvp; + cred_t *cr = ap->a_cnp->cn_cred; + char *name = ap->a_cnp->cn_nameptr; + znode_t *dzp = VTOZ(dvp); + znode_t *zp; + vnode_t *vp; + zfsvfs_t *zfsvfs = dzp->z_zfsvfs; + zilog_t *zilog = zfsvfs->z_log; + zfs_dirlock_t *dl; + dmu_tx_t *tx; + int error; + + ASSERT(ap->a_cnp->cn_flags & SAVENAME); + + ZFS_ENTER(zfsvfs); +top: + zp = NULL; + + /* + * Attempt to lock directory; fail if entry doesn't exist. + */ + if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZEXISTS)) { + ZFS_EXIT(zfsvfs); + return (error); + } + + vp = ZTOV(zp); + ASSERT(vp == ap->a_vp); + ASSERT(vp->v_type == VDIR); + /* Drop an extra reference from zfs_dirent_lock(). */ + VN_RELE(vp); + ASSERT(vp->v_count > 0); + + if (error = zfs_zaccess_delete(dzp, zp, cr)) { + goto out; + } + + /* + * Grab a lock on the directory to make sure that noone 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_bonus(tx, zp->z_id); + dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); + error = dmu_tx_assign(tx, zfsvfs->z_assign); + if (error) { + rw_exit(&zp->z_parent_lock); + rw_exit(&zp->z_name_lock); + zfs_dirent_unlock(dl); + if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { + dmu_tx_wait(tx); + dmu_tx_abort(tx); + goto top; + } + dmu_tx_abort(tx); + ZFS_EXIT(zfsvfs); + return (error); + } + +#ifdef FREEBSD_NAMECACHE + cache_purge(dvp); +#endif + + error = zfs_link_destroy(dl, zp, tx, 0, NULL); + + if (error == 0) + zfs_log_remove(zilog, tx, TX_RMDIR, dzp, name); + + dmu_tx_commit(tx); + + rw_exit(&zp->z_parent_lock); + rw_exit(&zp->z_name_lock); +#ifdef FREEBSD_NAMECACHE + cache_purge(vp); +#endif +out: + zfs_dirent_unlock(dl); + + ZFS_EXIT(zfsvfs); + return (error); +} + +/* + * Read as many directory entries as will fit into the provided + * buffer from the given directory cursor position (specified in + * the uio structure. + * + * IN: vp - vnode of directory to read. + * uio - structure supplying read location, range info, + * and return buffer. + * cr - credentials of caller. + * + * OUT: uio - updated offset and range, buffer filled. + * eofp - set to true if end-of-file detected. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * vp - 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. + */ +/* ARGSUSED */ +static int +zfs_readdir(ap) + struct vop_readdir_args /* { + struct vnode *a_vp; + struct uio *a_uio; + struct ucred *a_cred; + int *a_eofflag; + int *ncookies; + u_long **a_cookies; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + uio_t *uio = ap->a_uio; + int *eofp = ap->a_eofflag; + znode_t *zp = VTOZ(vp); + iovec_t *iovp; + dirent64_t *odp; + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + objset_t *os; + caddr_t outbuf; + size_t bufsize; + zap_cursor_t zc; + zap_attribute_t zap; + uint_t bytes_wanted; + uint64_t offset; /* must be unsigned; checks for < 1 */ + int local_eof; + int outcount; + int error; + uint8_t prefetch; + uint8_t type; + int ncookies; + u_long *cookies = NULL; + + ZFS_ENTER(zfsvfs); + + /* + * If we are not given an eof variable, + * use a local one. + */ + if (eofp == NULL) + eofp = &local_eof; + + /* + * Check for valid iov_len. + */ + if (uio->uio_iov->iov_len <= 0) { + ZFS_EXIT(zfsvfs); + return (EINVAL); + } + + /* + * Quit if directory has been removed (posix) + */ + if ((*eofp = zp->z_unlinked) != 0) { + ZFS_EXIT(zfsvfs); + return (0); + } + + error = 0; + os = zfsvfs->z_os; + offset = uio->uio_loffset; + prefetch = zp->z_zn_prefetch; + + /* + * 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); + } + + /* + * Get space to change directory entries into fs independent format. + */ + iovp = uio->uio_iov; + bytes_wanted = iovp->iov_len; + if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1) { + bufsize = bytes_wanted; + outbuf = kmem_alloc(bufsize, KM_SLEEP); + odp = (struct dirent64 *)outbuf; + } else { + bufsize = bytes_wanted; + odp = (struct dirent64 *)iovp->iov_base; + } + + if (ap->a_ncookies) { + /* + * Minimum entry size is dirent size and 1 byte for a file name. + */ + ncookies = uio->uio_resid / (sizeof(struct dirent) - sizeof(((struct dirent *)NULL)->d_name) + 1); + cookies = malloc(ncookies * sizeof(u_long), M_TEMP, M_WAITOK); + *ap->a_cookies = cookies; + *ap->a_ncookies = ncookies; + } + + /* + * Transform to file-system independent format + */ + outcount = 0; + while (outcount < bytes_wanted) { + ino64_t objnum; + ushort_t reclen; + + /* + * Special case `.', `..', and `.zfs'. + */ + if (offset == 0) { + (void) strcpy(zap.za_name, "."); + objnum = zp->z_id; + } else if (offset == 1) { + (void) strcpy(zap.za_name, ".."); + objnum = zp->z_phys->zp_parent; + } else if (offset == 2 && zfs_show_ctldir(zp)) { + (void) strcpy(zap.za_name, ZFS_CTLDIR_NAME); + objnum = ZFSCTL_INO_ROOT; + } else { + /* + * Grab next entry. + */ + if (error = zap_cursor_retrieve(&zc, &zap)) { + if ((*eofp = (error == ENOENT)) != 0) + break; + else + goto update; + } + + if (zap.za_integer_length != 8 || + zap.za_num_integers != 1) { + cmn_err(CE_WARN, "zap_readdir: bad directory " + "entry, obj = %lld, offset = %lld\n", + (u_longlong_t)zp->z_id, + (u_longlong_t)offset); + error = ENXIO; + goto update; + } + + objnum = ZFS_DIRENT_OBJ(zap.za_first_integer); + /* + * MacOS X can extract the object type here such as: + * uint8_t type = ZFS_DIRENT_TYPE(zap.za_first_integer); + */ + type = ZFS_DIRENT_TYPE(zap.za_first_integer); + } + reclen = DIRENT64_RECLEN(strlen(zap.za_name)); + + /* + * Will this entry fit in the buffer? + */ + if (outcount + reclen > bufsize) { + /* + * Did we manage to fit anything in the buffer? + */ + if (!outcount) { + error = EINVAL; + goto update; + } + break; + } + /* + * Add this entry: + */ + odp->d_ino = objnum; + odp->d_reclen = reclen; + odp->d_namlen = strlen(zap.za_name); + (void) strlcpy(odp->d_name, zap.za_name, odp->d_namlen + 1); + odp->d_type = type; + outcount += reclen; + odp = (dirent64_t *)((intptr_t)odp + reclen); + + ASSERT(outcount <= bufsize); + + /* Prefetch znode */ + if (prefetch) + dmu_prefetch(os, objnum, 0, 0); + + /* + * 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; + } + + if (cookies != NULL) { + *cookies++ = offset; + ncookies--; + KASSERT(ncookies >= 0, ("ncookies=%d", ncookies)); + } + } + zp->z_zn_prefetch = B_FALSE; /* a lookup will re-enable pre-fetching */ + + /* Subtract unused cookies */ + if (ap->a_ncookies) + *ap->a_ncookies -= ncookies; + + if (uio->uio_segflg == UIO_SYSSPACE && uio->uio_iovcnt == 1) { + iovp->iov_base += outcount; + iovp->iov_len -= outcount; + uio->uio_resid -= outcount; + } else if (error = uiomove(outbuf, (long)outcount, UIO_READ, uio)) { + /* + * Reset the pointer. + */ + offset = uio->uio_loffset; + } + +update: + zap_cursor_fini(&zc); + if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1) + kmem_free(outbuf, bufsize); + + if (error == ENOENT) + error = 0; + + ZFS_ACCESSTIME_STAMP(zfsvfs, zp); + + uio->uio_loffset = offset; + ZFS_EXIT(zfsvfs); + if (error != 0) { + free(*ap->a_cookies, M_TEMP); + *ap->a_cookies = NULL; + *ap->a_ncookies = 0; + } + return (error); +} + +static int +zfs_fsync(struct vop_fsync_args *ap) +{ + znode_t *zp = VTOZ(ap->a_vp); + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + + vop_stdfsync(ap); + + ZFS_ENTER(zfsvfs); + zil_commit(zfsvfs->z_log, zp->z_last_itx, zp->z_id); + ZFS_EXIT(zfsvfs); + return (0); +} + +/* + * Get the requested file attributes and place them in the provided + * vattr structure. + * + * IN: vp - vnode of file. + * vap - va_mask identifies requested attributes. + * flags - [UNUSED] + * cr - credentials of caller. + * + * OUT: vap - attribute values. + * + * RETURN: 0 (always succeeds) + */ +/* ARGSUSED */ +static int +zfs_getattr(ap) + struct vop_getattr_args /* { + struct vnode *a_vp; + struct vattr *a_vap; + struct ucred *a_cred; + struct thread *a_td; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + vattr_t *vap = ap->a_vap; + cred_t *cr = ap->a_cred; + znode_t *zp = VTOZ(vp); + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + znode_phys_t *pzp = zp->z_phys; + uint32_t blksize; + u_longlong_t nblocks; + int error; + + ZFS_ENTER(zfsvfs); + + /* + * Return all attributes. It's cheaper to provide the answer + * than to determine whether we were asked the question. + */ + mutex_enter(&zp->z_lock); + + vap->va_type = IFTOVT(pzp->zp_mode); + vap->va_mode = pzp->zp_mode & ~S_IFMT; + vap->va_uid = zp->z_phys->zp_uid; + vap->va_gid = zp->z_phys->zp_gid; + vap->va_nodeid = zp->z_id; + vap->va_nlink = MIN(pzp->zp_links, UINT32_MAX); /* nlink_t limit! */ + vap->va_size = pzp->zp_size; + vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0]; + vap->va_seq = zp->z_seq; + vap->va_flags = 0; /* FreeBSD: Reset chflags(2) flags. */ + + ZFS_TIME_DECODE(&vap->va_atime, pzp->zp_atime); + ZFS_TIME_DECODE(&vap->va_mtime, pzp->zp_mtime); + ZFS_TIME_DECODE(&vap->va_ctime, pzp->zp_ctime); + ZFS_TIME_DECODE(&vap->va_birthtime, pzp->zp_crtime); + + /* + * If ACL is trivial don't bother looking for ACE_READ_ATTRIBUTES. + * Also, if we are the owner don't bother, since owner should + * always be allowed to read basic attributes of file. + */ + if (!(zp->z_phys->zp_flags & ZFS_ACL_TRIVIAL) && + (zp->z_phys->zp_uid != crgetuid(cr))) { + if (error = zfs_zaccess(zp, ACE_READ_ATTRIBUTES, cr)) { + mutex_exit(&zp->z_lock); + ZFS_EXIT(zfsvfs); + return (error); + } + } + + mutex_exit(&zp->z_lock); + + dmu_object_size_from_db(zp->z_dbuf, &blksize, &nblocks); + vap->va_blksize = blksize; + vap->va_bytes = nblocks << 9; /* nblocks * 512 */ + + if (zp->z_blksz == 0) { + /* + * Block size hasn't been set; suggest maximal I/O transfers. + */ + vap->va_blksize = zfsvfs->z_max_blksz; + } + + ZFS_EXIT(zfsvfs); + return (0); +} + +/* + * Set the file attributes to the values contained in the + * vattr structure. + * + * IN: vp - vnode of file to be modified. + * vap - new attribute values. + * flags - ATTR_UTIME set if non-default time values provided. + * cr - credentials of caller. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * vp - ctime updated, mtime updated if size changed. + */ +/* ARGSUSED */ +static int +zfs_setattr(ap) + struct vop_setattr_args /* { + struct vnode *a_vp; + struct vattr *a_vap; + struct ucred *a_cred; + struct thread *a_td; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + vattr_t *vap = ap->a_vap; + cred_t *cr = ap->a_cred; + znode_t *zp = VTOZ(vp); + znode_phys_t *pzp = zp->z_phys; + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + zilog_t *zilog = zfsvfs->z_log; + dmu_tx_t *tx; + vattr_t oldva; + uint_t mask; + uint_t saved_mask; + int trim_mask = 0; + uint64_t new_mode; + znode_t *attrzp; + int need_policy = FALSE; + int flags = 0; + int err; + + /* No support for FreeBSD's chflags(2). */ + if (vap->va_flags != VNOVAL) + return (EOPNOTSUPP); + + vattr_init_mask(vap); + mask = vap->va_mask; + + if (mask == 0) + return (0); + + if (mask & AT_SIZE && vp->v_type == VDIR) + return (EISDIR); + + if (mask & AT_SIZE && vp->v_type != VREG && vp->v_type != VFIFO) + return (EINVAL); + + ZFS_ENTER(zfsvfs); + +top: + attrzp = NULL; + + if (zfsvfs->z_vfs->vfs_flag & VFS_RDONLY) { + ZFS_EXIT(zfsvfs); + return (EROFS); + } + + /* + * First validate permissions + */ + + if (mask & AT_SIZE) { + err = zfs_zaccess(zp, ACE_WRITE_DATA, cr); + if (err) { + ZFS_EXIT(zfsvfs); + return (err); + } + /* + * 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(). + */ + do { + err = zfs_freesp(zp, vap->va_size, 0, 0, FALSE); + /* NB: we already did dmu_tx_wait() if necessary */ + } while (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT); + if (err) { + ZFS_EXIT(zfsvfs); + return (err); + } + } + + if (mask & (AT_ATIME|AT_MTIME)) + need_policy = zfs_zaccess_v4_perm(zp, ACE_WRITE_ATTRIBUTES, cr); + + if (mask & (AT_UID|AT_GID)) { + int idmask = (mask & (AT_UID|AT_GID)); + int take_owner; + int take_group; + + /* + * NOTE: even if a new mode is being set, + * we may clear S_ISUID/S_ISGID bits. + */ + + if (!(mask & AT_MODE)) + vap->va_mode = pzp->zp_mode; + + /* + * Take ownership or chgrp to group we are a member of + */ + + take_owner = (mask & AT_UID) && (vap->va_uid == crgetuid(cr)); + take_group = (mask & AT_GID) && groupmember(vap->va_gid, cr); + + /* + * If both AT_UID and AT_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 == (AT_UID|AT_GID)) && take_owner && take_group) || + ((idmask == AT_UID) && take_owner) || + ((idmask == AT_GID) && take_group)) { + if (zfs_zaccess_v4_perm(zp, ACE_WRITE_OWNER, cr) == 0) { + /* + * Remove setuid/setgid for non-privileged users + */ + secpolicy_setid_clear(vap, cr); + trim_mask = (mask & (AT_UID|AT_GID)); + } else { + need_policy = TRUE; + } + } else { + need_policy = TRUE; + } + } + + mutex_enter(&zp->z_lock); + oldva.va_mode = pzp->zp_mode; + oldva.va_uid = zp->z_phys->zp_uid; + oldva.va_gid = zp->z_phys->zp_gid; + mutex_exit(&zp->z_lock); + + if (mask & AT_MODE) { + if (zfs_zaccess_v4_perm(zp, ACE_WRITE_ACL, cr) == 0) { + err = secpolicy_setid_setsticky_clear(vp, vap, + &oldva, cr); + if (err) { + ZFS_EXIT(zfsvfs); + return (err); + } + trim_mask |= AT_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, vp, vap, &oldva, flags, + (int (*)(void *, int, cred_t *))zfs_zaccess_rwx, zp); + if (err) { + ZFS_EXIT(zfsvfs); + return (err); + } + + if (trim_mask) + vap->va_mask |= saved_mask; + } + + /* + * secpolicy_vnode_setattr, or take ownership may have + * changed va_mask + */ + mask = vap->va_mask; + + tx = dmu_tx_create(zfsvfs->z_os); + dmu_tx_hold_bonus(tx, zp->z_id); + + if (mask & AT_MODE) { + uint64_t pmode = pzp->zp_mode; + + new_mode = (pmode & S_IFMT) | (vap->va_mode & ~S_IFMT); + + if (zp->z_phys->zp_acl.z_acl_extern_obj) + dmu_tx_hold_write(tx, + pzp->zp_acl.z_acl_extern_obj, 0, SPA_MAXBLOCKSIZE); + else + dmu_tx_hold_write(tx, DMU_NEW_OBJECT, + 0, ZFS_ACL_SIZE(MAX_ACL_SIZE)); + } + + if ((mask & (AT_UID | AT_GID)) && zp->z_phys->zp_xattr != 0) { + err = zfs_zget(zp->z_zfsvfs, zp->z_phys->zp_xattr, &attrzp); + if (err) { + dmu_tx_abort(tx); + ZFS_EXIT(zfsvfs); + return (err); + } + dmu_tx_hold_bonus(tx, attrzp->z_id); + } + + err = dmu_tx_assign(tx, zfsvfs->z_assign); + if (err) { + if (attrzp) + VN_RELE(ZTOV(attrzp)); + if (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { + dmu_tx_wait(tx); + dmu_tx_abort(tx); + goto top; + } + dmu_tx_abort(tx); + ZFS_EXIT(zfsvfs); + return (err); + } + + dmu_buf_will_dirty(zp->z_dbuf, tx); + + /* + * 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. + */ + + mutex_enter(&zp->z_lock); + + if (mask & AT_MODE) { + err = zfs_acl_chmod_setattr(zp, new_mode, tx); + ASSERT3U(err, ==, 0); + } + + if (attrzp) + mutex_enter(&attrzp->z_lock); + + if (mask & AT_UID) { + zp->z_phys->zp_uid = (uint64_t)vap->va_uid; + if (attrzp) { + attrzp->z_phys->zp_uid = (uint64_t)vap->va_uid; + } + } + + if (mask & AT_GID) { + zp->z_phys->zp_gid = (uint64_t)vap->va_gid; + if (attrzp) + attrzp->z_phys->zp_gid = (uint64_t)vap->va_gid; + } + + if (attrzp) + mutex_exit(&attrzp->z_lock); + + if (mask & AT_ATIME) + ZFS_TIME_ENCODE(&vap->va_atime, pzp->zp_atime); + + if (mask & AT_MTIME) + ZFS_TIME_ENCODE(&vap->va_mtime, pzp->zp_mtime); + + if (mask & AT_SIZE) + zfs_time_stamper_locked(zp, CONTENT_MODIFIED, tx); + else if (mask != 0) + zfs_time_stamper_locked(zp, STATE_CHANGED, tx); + + if (mask != 0) + zfs_log_setattr(zilog, tx, TX_SETATTR, zp, vap, mask); + + mutex_exit(&zp->z_lock); + + if (attrzp) + VN_RELE(ZTOV(attrzp)); + + dmu_tx_commit(tx); + + ZFS_EXIT(zfsvfs); + 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) + VN_RELE(ZTOV(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 = zp->z_zfsvfs->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 (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(zp->z_zfsvfs, *oidp, &zp); + if (error) + return (error); + zl->zl_znode = zp; + } + oidp = &zp->z_phys->zp_parent; + 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: sdvp - Source directory containing the "old entry". + * snm - Old entry name. + * tdvp - Target directory to contain the "new entry". + * tnm - New entry name. + * cr - credentials of caller. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * sdvp,tdvp - ctime|mtime updated + */ +static int +zfs_rename(ap) + struct vop_rename_args /* { + struct vnode *a_fdvp; + struct vnode *a_fvp; + struct componentname *a_fcnp; + struct vnode *a_tdvp; + struct vnode *a_tvp; + struct componentname *a_tcnp; + } */ *ap; +{ + vnode_t *svp = ap->a_fvp; + vnode_t *tvp = ap->a_tvp; + vnode_t *sdvp = ap->a_fdvp; + vnode_t *tdvp = ap->a_tdvp; + char *snm = ap->a_fcnp->cn_nameptr; + char *tnm = ap->a_tcnp->cn_nameptr; + cred_t *cr = ap->a_fcnp->cn_cred; + znode_t *tdzp, *szp, *tzp; + znode_t *sdzp = VTOZ(sdvp); + zfsvfs_t *zfsvfs = sdzp->z_zfsvfs; + zilog_t *zilog = zfsvfs->z_log; + zfs_dirlock_t *sdl, *tdl; + dmu_tx_t *tx; + zfs_zlock_t *zl; + int serr, terr, error; + + ASSERT(ap->a_fcnp->cn_flags & SAVENAME); + ASSERT(ap->a_tcnp->cn_flags & SAVENAME); + + ZFS_ENTER(zfsvfs); + + if (tdvp->v_vfsp != sdvp->v_vfsp) { + error = EXDEV; +abort: + ZFS_EXIT(zfsvfs); + if (tdvp == tvp) + vrele(tdvp); + else + vput(tdvp); + if (tvp) + vput(tvp); + vrele(sdvp); + vrele(svp); + return (error); + } + + tdzp = VTOZ(tdvp); +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_phys->zp_flags & ZFS_XATTR) != + (sdzp->z_phys->zp_flags & ZFS_XATTR)) { + error = EINVAL; + goto abort; + } + + /* + * 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." + * This case is already handled in kern_rename(). + */ + ASSERT(svp != tvp); + + /* + * 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) { + serr = zfs_dirent_lock(&sdl, sdzp, snm, &szp, ZEXISTS); + terr = zfs_dirent_lock(&tdl, tdzp, tnm, &tzp, 0); + } else /* if (sdzp->z_id > tdzp->z_id) */ { + terr = zfs_dirent_lock(&tdl, tdzp, tnm, &tzp, 0); + serr = zfs_dirent_lock(&sdl, sdzp, snm, &szp, ZEXISTS); + } + if (!terr && tzp != NULL) { + if (tvp) + vrele(tvp); + else { + ZFS_LOG(0, "Unexpected code path, report to pjd@FreeBSD.org"); + tvp = ZTOV(tzp); + vn_lock(tvp, LK_EXCLUSIVE | LK_RETRY, curthread); + } + ASSERT(tvp->v_count > 0); + } + + if (serr || svp != ZTOV(szp)) { + /* + * Source entry invalid or not there. + */ + if (!serr) + zfs_dirent_unlock(sdl); + if (!terr) + zfs_dirent_unlock(tdl); + if (strcmp(snm, ".") == 0 || strcmp(snm, "..") == 0) + serr = EINVAL; + error = serr; + goto abort; + } + if (terr) { + zfs_dirent_unlock(sdl); + if (strcmp(tnm, "..") == 0) + terr = EINVAL; + error = terr; + goto abort; + } + /* Remove an extra reference from zfs_dirent_lock(). */ + vrele(svp); + ASSERT(svp->v_count > 0); + + /* + * 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)) + goto out; + + if (svp->v_type == VDIR) { + /* + * 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) { + /* + * Source and target must be the same type. + */ + if (svp->v_type == VDIR) { + if (tvp->v_type != VDIR) { + error = ENOTDIR; + goto out; + } + } else { + if (tvp->v_type == VDIR) { + error = 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; + } + } + + tx = dmu_tx_create(zfsvfs->z_os); + dmu_tx_hold_bonus(tx, szp->z_id); /* nlink changes */ + dmu_tx_hold_bonus(tx, sdzp->z_id); /* nlink changes */ + dmu_tx_hold_zap(tx, sdzp->z_id, FALSE, snm); + dmu_tx_hold_zap(tx, tdzp->z_id, TRUE, tnm); + if (sdzp != tdzp) + dmu_tx_hold_bonus(tx, tdzp->z_id); /* nlink changes */ + if (tzp) + dmu_tx_hold_bonus(tx, tzp->z_id); /* parent changes */ + dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); + error = dmu_tx_assign(tx, zfsvfs->z_assign); + if (error) { + if (zl != NULL) + zfs_rename_unlock(&zl); + zfs_dirent_unlock(sdl); + zfs_dirent_unlock(tdl); + if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { + dmu_tx_wait(tx); + dmu_tx_abort(tx); + if (ap->a_tvp == NULL && tvp != NULL) { + vput(tvp); + tvp = NULL; + } + goto top; + } + dmu_tx_abort(tx); + goto abort; + } + + if (tzp) /* Attempt to remove the existing target */ + error = zfs_link_destroy(tdl, tzp, tx, 0, NULL); + + if (error == 0) { + error = zfs_link_create(tdl, szp, tx, ZRENAMING); + if (error == 0) { + error = zfs_link_destroy(sdl, szp, tx, ZRENAMING, NULL); + ASSERT(error == 0); + zfs_log_rename(zilog, tx, TX_RENAME, sdzp, + sdl->dl_name, tdzp, tdl->dl_name, szp); + } +#ifdef FREEBSD_NAMECACHE + if (error == 0) { + cache_purge(sdvp); + cache_purge(tdvp); + } +#endif + } + + dmu_tx_commit(tx); +out: + if (zl != NULL) + zfs_rename_unlock(&zl); + + zfs_dirent_unlock(sdl); + zfs_dirent_unlock(tdl); + + if (tzp) + vput(tvp); + vput(tdvp); + vrele(sdvp); + vrele(svp); + + ZFS_EXIT(zfsvfs); + + return (error); +} + +/* + * Insert the indicated symbolic reference entry into the directory. + * + * IN: dvp - Directory to contain new symbolic link. + * link - Name for new symlink entry. + * vap - Attributes of new entry. + * target - Target path of new symlink. + * cr - credentials of caller. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * dvp - ctime|mtime updated + */ +static int +zfs_symlink(ap) + struct vop_symlink_args /* { + struct vnode *a_dvp; + struct vnode **a_vpp; + struct componentname *a_cnp; + struct vattr *a_vap; + char *a_target; + } */ *ap; +{ + vnode_t *dvp = ap->a_dvp; + vattr_t *vap = ap->a_vap; + cred_t *cr = ap->a_cnp->cn_cred; + char *name = ap->a_cnp->cn_nameptr; + char *link = ap->a_target; + znode_t *zp, *dzp = VTOZ(dvp); + zfs_dirlock_t *dl; + dmu_tx_t *tx; + zfsvfs_t *zfsvfs = dzp->z_zfsvfs; + zilog_t *zilog = zfsvfs->z_log; + uint64_t zoid; + int len = strlen(link); + int error; + + ASSERT(ap->a_cnp->cn_flags & SAVENAME); + + vap->va_type = VLNK; /* FreeBSD: Syscall only sets va_mode. */ + vattr_init_mask(vap); + + ZFS_ENTER(zfsvfs); +top: + if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) { + ZFS_EXIT(zfsvfs); + return (error); + } + + if (len > MAXPATHLEN) { + ZFS_EXIT(zfsvfs); + return (ENAMETOOLONG); + } + + /* + * Attempt to lock directory; fail if entry already exists. + */ + if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZNEW)) { + ZFS_EXIT(zfsvfs); + return (error); + } + + tx = dmu_tx_create(zfsvfs->z_os); + dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, MAX(1, len)); + dmu_tx_hold_bonus(tx, dzp->z_id); + dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name); + if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) + dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, SPA_MAXBLOCKSIZE); + error = dmu_tx_assign(tx, zfsvfs->z_assign); + if (error) { + zfs_dirent_unlock(dl); + if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { + dmu_tx_wait(tx); + dmu_tx_abort(tx); + goto top; + } + dmu_tx_abort(tx); + ZFS_EXIT(zfsvfs); + return (error); + } + + dmu_buf_will_dirty(dzp->z_dbuf, tx); + + /* + * Create a new object for the symlink. + * Put the link content into bonus buffer if it will fit; + * otherwise, store it just like any other file data. + */ + zoid = 0; + if (sizeof (znode_phys_t) + len <= dmu_bonus_max()) { + zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, len); + if (len != 0) + bcopy(link, zp->z_phys + 1, len); + } else { + dmu_buf_t *dbp; + + zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0); + + /* + * Nothing can access the znode yet so no locking needed + * for growing the znode's blocksize. + */ + zfs_grow_blocksize(zp, len, tx); + + VERIFY(0 == dmu_buf_hold(zfsvfs->z_os, zoid, 0, FTAG, &dbp)); + dmu_buf_will_dirty(dbp, tx); + + ASSERT3U(len, <=, dbp->db_size); + bcopy(link, dbp->db_data, len); + dmu_buf_rele(dbp, FTAG); + } + zp->z_phys->zp_size = len; + + /* + * Insert the new object into the directory. + */ + (void) zfs_link_create(dl, zp, tx, ZNEW); + + if (error == 0) { + zfs_log_symlink(zilog, tx, TX_SYMLINK, dzp, zp, name, link); + + *ap->a_vpp = ZTOV(zp); + + vn_lock(ZTOV(zp), LK_EXCLUSIVE | LK_RETRY, + ap->a_cnp->cn_thread); + } + + dmu_tx_commit(tx); + + zfs_dirent_unlock(dl); + + ZFS_EXIT(zfsvfs); + return (error); +} + +/* + * Return, in the buffer contained in the provided uio structure, + * the symbolic path referred to by vp. + * + * IN: vp - vnode of symbolic link. + * uoip - structure to contain the link path. + * cr - credentials of caller. + * + * OUT: uio - structure to contain the link path. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * vp - atime updated + */ +/* ARGSUSED */ +static int +zfs_readlink(ap) + struct vop_readlink_args /* { + struct vnode *a_vp; + struct uio *a_uio; + struct ucred *a_cred; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + uio_t *uio = ap->a_uio; + znode_t *zp = VTOZ(vp); + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + size_t bufsz; + int error; + + ZFS_ENTER(zfsvfs); + + bufsz = (size_t)zp->z_phys->zp_size; + if (bufsz + sizeof (znode_phys_t) <= zp->z_dbuf->db_size) { + error = uiomove(zp->z_phys + 1, + MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio); + } else { + dmu_buf_t *dbp; + error = dmu_buf_hold(zfsvfs->z_os, zp->z_id, 0, FTAG, &dbp); + if (error) { + ZFS_EXIT(zfsvfs); + return (error); + } + error = uiomove(dbp->db_data, + MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio); + dmu_buf_rele(dbp, FTAG); + } + + ZFS_ACCESSTIME_STAMP(zfsvfs, zp); + ZFS_EXIT(zfsvfs); + return (error); +} + +/* + * Insert a new entry into directory tdvp referencing svp. + * + * IN: tdvp - Directory to contain new entry. + * svp - vnode of new entry. + * name - name of new entry. + * cr - credentials of caller. + * + * RETURN: 0 if success + * error code if failure + * + * Timestamps: + * tdvp - ctime|mtime updated + * svp - ctime updated + */ +/* ARGSUSED */ +static int +zfs_link(ap) + struct vop_link_args /* { + struct vnode *a_tdvp; + struct vnode *a_vp; + struct componentname *a_cnp; + } */ *ap; +{ + vnode_t *svp = ap->a_vp; + vnode_t *tdvp = ap->a_tdvp; + cred_t *cr = ap->a_cnp->cn_cred; + char *name = ap->a_cnp->cn_nameptr; + znode_t *dzp = VTOZ(tdvp); + znode_t *tzp, *szp; + zfsvfs_t *zfsvfs = dzp->z_zfsvfs; + zilog_t *zilog = zfsvfs->z_log; + zfs_dirlock_t *dl; + dmu_tx_t *tx; + int error; + + ASSERT(ap->a_cnp->cn_flags & SAVENAME); + ASSERT(tdvp->v_type == VDIR); + + ZFS_ENTER(zfsvfs); + + if (svp->v_vfsp != tdvp->v_vfsp) { + ZFS_EXIT(zfsvfs); + return (EXDEV); + } + + szp = VTOZ(svp); +top: + /* + * 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_phys->zp_flags & ZFS_XATTR) != + (dzp->z_phys->zp_flags & ZFS_XATTR)) { + ZFS_EXIT(zfsvfs); + return (EINVAL); + } + + /* + * POSIX dictates that we return EPERM here. + * Better choices include ENOTSUP or EISDIR. + */ + if (svp->v_type == VDIR) { + ZFS_EXIT(zfsvfs); + return (EPERM); + } + + if ((uid_t)szp->z_phys->zp_uid != crgetuid(cr) && + secpolicy_basic_link(cr) != 0) { + ZFS_EXIT(zfsvfs); + return (EPERM); + } + + if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) { + ZFS_EXIT(zfsvfs); + return (error); + } + + /* + * Attempt to lock directory; fail if entry already exists. + */ + if (error = zfs_dirent_lock(&dl, dzp, name, &tzp, ZNEW)) { + ZFS_EXIT(zfsvfs); + return (error); + } + + tx = dmu_tx_create(zfsvfs->z_os); + dmu_tx_hold_bonus(tx, szp->z_id); + dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name); + error = dmu_tx_assign(tx, zfsvfs->z_assign); + if (error) { + zfs_dirent_unlock(dl); + if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { + dmu_tx_wait(tx); + dmu_tx_abort(tx); + goto top; + } + dmu_tx_abort(tx); + ZFS_EXIT(zfsvfs); + return (error); + } + + error = zfs_link_create(dl, szp, tx, 0); + + if (error == 0) + zfs_log_link(zilog, tx, TX_LINK, dzp, szp, name); + + dmu_tx_commit(tx); + + zfs_dirent_unlock(dl); + + ZFS_EXIT(zfsvfs); + return (error); +} + +static int +zfs_inactive(ap) + struct vop_inactive_args /* { + struct vnode *a_vp; + struct thread *a_td; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + znode_t *zp = VTOZ(vp); + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + int error; + + /* + * Destroy the vm object and flush associated pages. + */ + vnode_destroy_vobject(vp); + + rw_enter(&zfsvfs->z_um_lock, RW_READER); + if (zfsvfs->z_unmounted2) { + ASSERT(zp->z_dbuf_held == 0); + + mutex_enter(&zp->z_lock); + VI_LOCK(vp); + vp->v_count = 0; /* count arrives as 1 */ + VI_UNLOCK(vp); + if (zp->z_dbuf == NULL) { + mutex_exit(&zp->z_lock); + zfs_znode_free(zp); + } else { + mutex_exit(&zp->z_lock); + } + rw_exit(&zfsvfs->z_um_lock); + VFS_RELE(zfsvfs->z_vfs); + return (0); + } + + if (zp->z_atime_dirty && zp->z_unlinked == 0) { + dmu_tx_t *tx = dmu_tx_create(zfsvfs->z_os); + + dmu_tx_hold_bonus(tx, zp->z_id); + error = dmu_tx_assign(tx, TXG_WAIT); + if (error) { + dmu_tx_abort(tx); + } else { + dmu_buf_will_dirty(zp->z_dbuf, tx); + mutex_enter(&zp->z_lock); + zp->z_atime_dirty = 0; + mutex_exit(&zp->z_lock); + dmu_tx_commit(tx); + } + } + + zfs_zinactive(zp); + rw_exit(&zfsvfs->z_um_lock); + return (0); +} + +static int +zfs_reclaim(ap) + struct vop_reclaim_args /* { + struct vnode *a_vp; + struct thread *a_td; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + znode_t *zp = VTOZ(vp); + + if (zp != NULL) + mutex_enter(&zp->z_lock); +#if 0 /* + * We do it from zfs_inactive(), because after zfs_inactive() we can't + * VOP_WRITE() to the vnode. + */ + /* + * Destroy the vm object and flush associated pages. + */ + vnode_destroy_vobject(vp); +#endif + VI_LOCK(vp); + vp->v_data = NULL; + if (zp != NULL) + zp->z_vnode = NULL; + ASSERT(vp->v_holdcnt > 1); + vdropl(vp); + if (zp != NULL) + mutex_exit(&zp->z_lock); + return (0); +} + +CTASSERT(sizeof(struct zfid_short) <= sizeof(struct fid)); +CTASSERT(sizeof(struct zfid_long) <= sizeof(struct fid)); + +static int +zfs_fid(ap) + struct vop_fid_args /* { + struct vnode *a_vp; + struct fid *a_fid; + } */ *ap; +{ + vnode_t *vp = ap->a_vp; + fid_t *fidp = (void *)ap->a_fid; + znode_t *zp = VTOZ(vp); + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + uint32_t gen = (uint32_t)zp->z_phys->zp_gen; + uint64_t object = zp->z_id; + zfid_short_t *zfid; + int size, i; + + ZFS_ENTER(zfsvfs); + + size = (zfsvfs->z_parent != zfsvfs) ? LONG_FID_LEN : SHORT_FID_LEN; + fidp->fid_len = size; + + 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)); + + if (size == LONG_FID_LEN) { + uint64_t objsetid = dmu_objset_id(zfsvfs->z_os); + zfid_long_t *zlfid; + + zlfid = (zfid_long_t *)fidp; + + for (i = 0; i < sizeof (zlfid->zf_setid); i++) + zlfid->zf_setid[i] = (uint8_t)(objsetid >> (8 * i)); + + /* XXX - this should be the generation number for the objset */ + for (i = 0; i < sizeof (zlfid->zf_setgen); i++) + zlfid->zf_setgen[i] = 0; + } + + ZFS_EXIT(zfsvfs); + return (0); +} + +static int +zfs_pathconf(ap) + struct vop_pathconf_args /* { + struct vnode *a_vp; + int a_name; + int *a_retval; + } */ *ap; +{ + int cmd = ap->a_name; + int *valp = ap->a_retval; +#if 0 + vnode_t *vp = ap->a_vp; + znode_t *zp, *xzp; + zfsvfs_t *zfsvfs; + zfs_dirlock_t *dl; + int error; +#endif + + switch (cmd) { + case _PC_LINK_MAX: + *valp = INT_MAX; + return (0); + + case _PC_FILESIZEBITS: + *valp = 64; + return (0); + +#if 0 + case _PC_XATTR_EXISTS: + zp = VTOZ(vp); + zfsvfs = zp->z_zfsvfs; + ZFS_ENTER(zfsvfs); + *valp = 0; + error = zfs_dirent_lock(&dl, zp, "", &xzp, + ZXATTR | ZEXISTS | ZSHARED); + if (error == 0) { + zfs_dirent_unlock(dl); + if (!zfs_dirempty(xzp)) + *valp = 1; + VN_RELE(ZTOV(xzp)); + } else if (error == ENOENT) { + /* + * If there aren't extended attributes, it's the + * same as having zero of them. + */ + error = 0; + } + ZFS_EXIT(zfsvfs); + return (error); +#endif + + case _PC_ACL_EXTENDED: + *valp = 0; /* TODO */ + return (0); + + case _PC_MIN_HOLE_SIZE: + *valp = (int)SPA_MINBLOCKSIZE; + return (0); + + default: + return (vop_stdpathconf(ap)); + } +} + +#ifdef TODO +/*ARGSUSED*/ +static int +zfs_getsecattr(vnode_t *vp, vsecattr_t *vsecp, int flag, cred_t *cr) +{ + znode_t *zp = VTOZ(vp); + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + int error; + + ZFS_ENTER(zfsvfs); + error = zfs_getacl(zp, vsecp, cr); + ZFS_EXIT(zfsvfs); + + return (error); +} +#endif /* TODO */ + +#ifdef TODO +/*ARGSUSED*/ +static int +zfs_setsecattr(vnode_t *vp, vsecattr_t *vsecp, int flag, cred_t *cr) +{ + znode_t *zp = VTOZ(vp); + zfsvfs_t *zfsvfs = zp->z_zfsvfs; + int error; + + ZFS_ENTER(zfsvfs); + error = zfs_setacl(zp, vsecp, cr); + ZFS_EXIT(zfsvfs); + return (error); +} +#endif /* TODO */ + +/* + * Advisory record locking support + */ +static int +zfs_advlock(ap) + struct vop_advlock_args /* { + struct vnode *a_vp; + caddr_t a_id; + int a_op; + struct flock *a_fl; + int a_flags; + } */ *ap; +{ + znode_t *zp = VTOZ(ap->a_vp); + + return (lf_advlock(ap, &(zp->z_lockf), zp->z_phys->zp_size)); +} + +struct vop_vector zfs_vnodeops; +struct vop_vector zfs_fifoops; + +struct vop_vector zfs_vnodeops = { + .vop_default = &default_vnodeops, + .vop_inactive = zfs_inactive, + .vop_reclaim = zfs_reclaim, + .vop_access = zfs_access, +#ifdef FREEBSD_NAMECACHE + .vop_lookup = vfs_cache_lookup, + .vop_cachedlookup = zfs_lookup, +#else + .vop_lookup = zfs_lookup, +#endif + .vop_getattr = zfs_getattr, + .vop_setattr = zfs_setattr, + .vop_create = zfs_create, + .vop_mknod = zfs_create, + .vop_mkdir = zfs_mkdir, + .vop_readdir = zfs_readdir, + .vop_fsync = zfs_fsync, + .vop_open = zfs_open, + .vop_close = zfs_close, + .vop_rmdir = zfs_rmdir, + .vop_ioctl = zfs_ioctl, + .vop_link = zfs_link, + .vop_symlink = zfs_symlink, + .vop_readlink = zfs_readlink, + .vop_read = zfs_read, + .vop_write = zfs_write, + .vop_remove = zfs_remove, + .vop_rename = zfs_rename, + .vop_advlock = zfs_advlock, + .vop_pathconf = zfs_pathconf, + .vop_bmap = VOP_EOPNOTSUPP, + .vop_fid = zfs_fid, +}; + +struct vop_vector zfs_fifoops = { + .vop_default = &fifo_specops, + .vop_fsync = VOP_PANIC, + .vop_access = zfs_access, + .vop_getattr = zfs_getattr, + .vop_inactive = zfs_inactive, + .vop_read = VOP_PANIC, + .vop_reclaim = zfs_reclaim, + .vop_setattr = zfs_setattr, + .vop_write = VOP_PANIC, + .vop_fid = zfs_fid, +}; |
