/*
- * Copyright (c) 2002-2005 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2002-2008 Apple Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
*
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
*
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ubc.h>
#include <sys/quota.h>
#include <sys/kdebug.h>
+#include <libkern/OSByteOrder.h>
#include <kern/locks.h>
#include <hfs/hfs_catalog.h>
#include <hfs/hfs_cnode.h>
#include <hfs/hfs_quota.h>
+#include <hfs/hfs_format.h>
extern int prtactive;
extern lck_grp_t * hfs_mutex_group;
extern lck_grp_t * hfs_rwlock_group;
-static int hfs_filedone(struct vnode *vp, vfs_context_t context);
-
static void hfs_reclaim_cnode(struct cnode *);
+static int hfs_cnode_teardown (struct vnode *vp, vfs_context_t ctx, int reclaim);
+static int hfs_isordered(struct cnode *, struct cnode *);
-static int hfs_valid_cnode(struct hfsmount *, struct vnode *, struct componentname *, cnid_t);
+__inline__ int hfs_checkdeleted (struct cnode *cp) {
+ return ((cp->c_flag & (C_DELETED | C_NOEXISTS)) ? ENOENT : 0);
+}
-static int hfs_isordered(struct cnode *, struct cnode *);
-int hfs_vnop_inactive(struct vnop_inactive_args *);
+/*
+ * Function used by a special fcntl() that decorates a cnode/vnode that
+ * indicates it is backing another filesystem, like a disk image.
+ *
+ * the argument 'val' indicates whether or not to set the bit in the cnode flags
+ *
+ * Returns non-zero on failure. 0 on success
+ */
+int hfs_set_backingstore (struct vnode *vp, int val) {
+ struct cnode *cp = NULL;
+ int err = 0;
+
+ cp = VTOC(vp);
+ if (!vnode_isreg(vp) && !vnode_isdir(vp)) {
+ return EINVAL;
+ }
-int hfs_vnop_reclaim(struct vnop_reclaim_args *);
+ /* lock the cnode */
+ err = hfs_lock (cp, HFS_EXCLUSIVE_LOCK);
+ if (err) {
+ return err;
+ }
+
+ if (val) {
+ cp->c_flag |= C_BACKINGSTORE;
+ }
+ else {
+ cp->c_flag &= ~C_BACKINGSTORE;
+ }
+ /* unlock everything */
+ hfs_unlock (cp);
+
+ return err;
+}
/*
- * Last reference to an cnode. If necessary, write or delete it.
+ * Function used by a special fcntl() that check to see if a cnode/vnode
+ * indicates it is backing another filesystem, like a disk image.
+ *
+ * the argument 'val' is an output argument for whether or not the bit is set
+ *
+ * Returns non-zero on failure. 0 on success
*/
-__private_extern__
-int
-hfs_vnop_inactive(struct vnop_inactive_args *ap)
-{
- struct vnode *vp = ap->a_vp;
- struct cnode *cp;
- struct hfsmount *hfsmp = VTOHFS(vp);
- struct proc *p = vfs_context_proc(ap->a_context);
- int error = 0;
- int recycle = 0;
- int forkcount = 0;
- int truncated = 0;
- int started_tr = 0;
- int took_trunc_lock = 0;
- cat_cookie_t cookie;
- int cat_reserve = 0;
- int lockflags;
- enum vtype v_type;
- v_type = vnode_vtype(vp);
- cp = VTOC(vp);
+int hfs_is_backingstore (struct vnode *vp, int *val) {
+ struct cnode *cp = NULL;
+ int err = 0;
- if ((hfsmp->hfs_flags & HFS_READ_ONLY) || vnode_issystem(vp) ||
- (hfsmp->hfs_freezing_proc == p)) {
- return (0);
+ if (!vnode_isreg(vp) && !vnode_isdir(vp)) {
+ *val = 0;
+ return 0;
}
- /*
- * Ignore nodes related to stale file handles.
- */
- if (cp->c_mode == 0) {
- vnode_recycle(vp);
- return (0);
- }
+ cp = VTOC(vp);
- if ((v_type == VREG) &&
- (ISSET(cp->c_flag, C_DELETED) || VTOF(vp)->ff_blocks)) {
- hfs_lock_truncate(cp, TRUE);
- took_trunc_lock = 1;
+ /* lock the cnode */
+ err = hfs_lock (cp, HFS_SHARED_LOCK);
+ if (err) {
+ return err;
}
- /*
- * We do the ubc_setsize before we take the cnode
- * lock and before the hfs_truncate (since we'll
- * be inside a transaction).
- */
- if ((v_type == VREG || v_type == VLNK) &&
- (cp->c_flag & C_DELETED) &&
- (VTOF(vp)->ff_blocks != 0)) {
- ubc_setsize(vp, 0);
+ if (cp->c_flag & C_BACKINGSTORE) {
+ *val = 1;
+ }
+ else {
+ *val = 0;
}
- (void) hfs_lock(cp, HFS_FORCE_LOCK);
+ /* unlock everything */
+ hfs_unlock (cp);
- if (v_type == VREG && !ISSET(cp->c_flag, C_DELETED) && VTOF(vp)->ff_blocks) {
- hfs_filedone(vp, ap->a_context);
+ return err;
+}
+
+
+/*
+ * hfs_cnode_teardown
+ *
+ * This is an internal function that is invoked from both hfs_vnop_inactive
+ * and hfs_vnop_reclaim. As VNOP_INACTIVE is not necessarily called from vnodes
+ * being recycled and reclaimed, it is important that we do any post-processing
+ * necessary for the cnode in both places. Important tasks include things such as
+ * releasing the blocks from an open-unlinked file when all references to it have dropped,
+ * and handling resource forks separately from data forks.
+ *
+ * Note that we take only the vnode as an argument here (rather than the cnode).
+ * Recall that each cnode supports two forks (rsrc/data), and we can always get the right
+ * cnode from either of the vnodes, but the reverse is not true -- we can't determine which
+ * vnode we need to reclaim if only the cnode is supplied.
+ *
+ * This function is idempotent and safe to call from both hfs_vnop_inactive and hfs_vnop_reclaim
+ * if both are invoked right after the other. In the second call, most of this function's if()
+ * conditions will fail, since they apply generally to cnodes still marked with C_DELETED.
+ * As a quick check to see if this function is necessary, determine if the cnode is already
+ * marked C_NOEXISTS. If it is, then it is safe to skip this function. The only tasks that
+ * remain for cnodes marked in such a fashion is to teardown their fork references and
+ * release all directory hints and hardlink origins. However, both of those are done
+ * in hfs_vnop_reclaim. hfs_update, by definition, is not necessary if the cnode's catalog
+ * entry is no longer there.
+ *
+ * 'reclaim' argument specifies whether or not we were called from hfs_vnop_reclaim. If we are
+ * invoked from hfs_vnop_reclaim, we can not call functions that cluster_push since the UBC info
+ * is totally gone by that point.
+ *
+ * Assumes that both truncate and cnode locks for 'cp' are held.
+ */
+static
+int hfs_cnode_teardown (struct vnode *vp, vfs_context_t ctx, int reclaim) {
+
+ int forkcount = 0;
+ enum vtype v_type;
+ struct cnode *cp;
+ int error = 0;
+ int started_tr = 0;
+ struct hfsmount *hfsmp = VTOHFS(vp);
+ struct proc *p = vfs_context_proc(ctx);
+ int truncated = 0;
+ cat_cookie_t cookie;
+ int cat_reserve = 0;
+ int lockflags;
+ int ea_error = 0;
+
+ v_type = vnode_vtype(vp);
+ cp = VTOC(vp);
+
+ if (cp->c_datafork) {
+ ++forkcount;
+ }
+ if (cp->c_rsrcfork) {
+ ++forkcount;
+ }
+
+
+ /*
+ * Skip the call to ubc_setsize if we're being invoked on behalf of reclaim.
+ * The dirty regions would have already been synced to disk, so informing UBC
+ * that they can toss the pages doesn't help anyone at this point.
+ *
+ * Note that this is a performance problem if the vnode goes straight to reclaim
+ * (and skips inactive), since there would be no way for anyone to notify the UBC
+ * that all pages in this file are basically useless.
+ */
+ if (reclaim == 0) {
+ /*
+ * Check whether we are tearing down a cnode with only one remaining fork.
+ * If there are blocks in its filefork, then we need to unlock the cnode
+ * before calling ubc_setsize. The cluster layer may re-enter the filesystem
+ * (i.e. VNOP_BLOCKMAP), and if we retain the cnode lock, we could double-lock
+ * panic.
+ */
+
+ if ((v_type == VREG || v_type == VLNK) &&
+ (cp->c_flag & C_DELETED) &&
+ (VTOF(vp)->ff_blocks != 0) && (forkcount == 1)) {
+ hfs_unlock(cp);
+ /* ubc_setsize just fails if we were to call this from VNOP_RECLAIM */
+ ubc_setsize(vp, 0);
+ (void) hfs_lock(cp, HFS_FORCE_LOCK);
+ }
+ }
+
+ /*
+ * Push file data out for normal files that haven't been evicted from
+ * the namespace. We only do this if this function was not called from reclaim,
+ * because by that point the UBC information has been totally torn down.
+ *
+ * There should also be no way that a normal file that has NOT been deleted from
+ * the namespace to skip INACTIVE and go straight to RECLAIM. That race only happens
+ * when the file becomes open-unlinked.
+ */
+ if ((v_type == VREG) &&
+ (!ISSET(cp->c_flag, C_DELETED)) &&
+ (!ISSET(cp->c_flag, C_NOEXISTS)) &&
+ (VTOF(vp)->ff_blocks) &&
+ (reclaim == 0)) {
+ hfs_filedone(vp, ctx);
}
/*
- * Remove any directory hints
+ * Remove any directory hints or cached origins
*/
- if (v_type == VDIR)
+ if (v_type == VDIR) {
hfs_reldirhints(cp, 0);
-
- if (cp->c_datafork)
- ++forkcount;
- if (cp->c_rsrcfork)
- ++forkcount;
-
- /* If needed, get rid of any fork's data for a deleted file */
- if ((v_type == VREG || v_type == VLNK) && (cp->c_flag & C_DELETED)) {
+ }
+ if (cp->c_flag & C_HARDLINK) {
+ hfs_relorigins(cp);
+ }
+
+ /*
+ * This check is slightly complicated. We should only truncate data
+ * in very specific cases for open-unlinked files. This is because
+ * we want to ensure that the resource fork continues to be available
+ * if the caller has the data fork open. However, this is not symmetric;
+ * someone who has the resource fork open need not be able to access the data
+ * fork once the data fork has gone inactive.
+ *
+ * If we're the last fork, then we have cleaning up to do.
+ *
+ * A) last fork, and vp == c_vp
+ * Truncate away own fork data. If rsrc fork is not in core, truncate it too.
+ *
+ * B) last fork, and vp == c_rsrc_vp
+ * Truncate ourselves, assume data fork has been cleaned due to C).
+ *
+ * If we're not the last fork, then things are a little different:
+ *
+ * C) not the last fork, vp == c_vp
+ * Truncate ourselves. Once the file has gone out of the namespace,
+ * it cannot be further opened. Further access to the rsrc fork may
+ * continue, however.
+ *
+ * D) not the last fork, vp == c_rsrc_vp
+ * Don't enter the block below, just clean up vnode and push it out of core.
+ */
+
+ if ((v_type == VREG || v_type == VLNK) &&
+ (cp->c_flag & C_DELETED) &&
+ ((forkcount == 1) || (!VNODE_IS_RSRC(vp)))) {
+
+ /* Truncate away our own fork data. (Case A, B, C above) */
if (VTOF(vp)->ff_blocks != 0) {
- // start the transaction out here so that
- // the truncate and the removal of the file
- // are all in one transaction. otherwise
- // because this cnode is marked for deletion
- // the truncate won't cause the catalog entry
- // to get updated which means that we could
- // free blocks but still keep a reference to
- // them in the catalog entry and then double
- // free them later.
- //
-// if (hfs_start_transaction(hfsmp) != 0) {
-// error = EINVAL;
-// goto out;
-// }
-// started_tr = 1;
-
/*
* Since we're already inside a transaction,
* tell hfs_truncate to skip the ubc_setsize.
+ *
+ * This truncate call (and the one below) is fine from VNOP_RECLAIM's
+ * context because we're only removing blocks, not zero-filling new
+ * ones. The C_DELETED check above makes things much simpler.
*/
- error = hfs_truncate(vp, (off_t)0, IO_NDELAY, 1, ap->a_context);
- if (error)
+ error = hfs_truncate(vp, (off_t)0, IO_NDELAY, 1, 0, ctx);
+ if (error) {
goto out;
+ }
truncated = 1;
}
- recycle = 1;
+
+ /*
+ * Truncate away the resource fork, if we represent the data fork and
+ * it is the last fork. That means, by definition, the rsrc fork is not in
+ * core. So we bring it into core, and then truncate it away.
+ *
+ * This is invoked via case A above only.
+ */
+ if ((cp->c_blocks > 0) && (forkcount == 1) && (vp != cp->c_rsrc_vp)) {
+ struct vnode *rvp = NULLVP;
+
+ /*
+ * It is safe for us to pass FALSE to the argument can_drop_lock
+ * on this call to hfs_vgetrsrc. We know that the resource fork does not
+ * exist in core, so we'll have to go to the catalog to retrieve its
+ * information. That will attach the resource fork vnode to our cnode.
+ */
+ error = hfs_vgetrsrc(hfsmp, vp, &rvp, FALSE, FALSE);
+ if (error) {
+ goto out;
+ }
+ /*
+ * Defer the vnode_put and ubc_setsize on rvp until hfs_unlock().
+ *
+ * By bringing the vnode into core above, we may force hfs_vnop_reclaim
+ * to only partially finish if that's what called us. Bringing the
+ * resource fork into core results in a new rsrc vnode that will get
+ * immediately marked for termination below. It will get recycled/reclaimed
+ * as soon as possible, but that could cause another round of inactive and reclaim.
+ */
+ cp->c_flag |= C_NEED_RVNODE_PUT | C_NEED_RSRC_SETSIZE;
+ error = hfs_truncate(rvp, (off_t)0, IO_NDELAY, 1, 0, ctx);
+ if (error) {
+ goto out;
+ }
+
+ /*
+ * Note that the following call to vnode_recycle is safe from within the
+ * context of hfs_vnop_inactive or hfs_vnop_reclaim. It is being invoked
+ * on the RSRC fork vp (which is not our current vnode) As such, we hold
+ * an iocount on it and vnode_recycle will just add the MARKTERM bit at this
+ * point.
+ */
+ vnode_recycle(rvp); /* all done with this vnode */
+ }
}
-
+
/*
- * Check for a postponed deletion.
- * (only delete cnode when the last fork goes inactive)
+ * If we represent the last fork (or none in the case of a dir),
+ * and the cnode has become open-unlinked,
+ * AND it has EA's, then we need to get rid of them.
+ *
+ * Note that this must happen outside of any other transactions
+ * because it starts/ends its own transactions and grabs its
+ * own locks. This is to prevent a file with a lot of attributes
+ * from creating a transaction that is too large (which panics).
*/
- if ((cp->c_flag & C_DELETED) && (forkcount <= 1)) {
- /*
- * Mark cnode in transit so that no one can get this
- * cnode from cnode hash.
- */
- hfs_chash_mark_in_transit(cp);
-
- cp->c_flag &= ~C_DELETED;
- cp->c_flag |= C_NOEXISTS; // XXXdbg
- cp->c_rdev = 0;
-
- if (started_tr == 0) {
- if (hfs_start_transaction(hfsmp) != 0) {
- error = EINVAL;
- goto out;
- }
- started_tr = 1;
- }
+ if ((cp->c_attr.ca_recflags & kHFSHasAttributesMask) != 0 &&
+ (cp->c_flag & C_DELETED) &&
+ (forkcount <= 1)) {
+
+ ea_error = hfs_removeallattr(hfsmp, cp->c_fileid);
+ }
+
+
+ /*
+ * If the cnode represented an open-unlinked file, then now
+ * actually remove the cnode's catalog entry and release all blocks
+ * it may have been using.
+ */
+ if ((cp->c_flag & C_DELETED) && (forkcount <= 1)) {
+ /*
+ * Mark cnode in transit so that no one can get this
+ * cnode from cnode hash.
+ */
+ // hfs_chash_mark_in_transit(hfsmp, cp);
+ // XXXdbg - remove the cnode from the hash table since it's deleted
+ // otherwise someone could go to sleep on the cnode and not
+ // be woken up until this vnode gets recycled which could be
+ // a very long time...
+ hfs_chashremove(hfsmp, cp);
+
+ cp->c_flag |= C_NOEXISTS; // XXXdbg
+ cp->c_rdev = 0;
+
+ if (started_tr == 0) {
+ if (hfs_start_transaction(hfsmp) != 0) {
+ error = EINVAL;
+ goto out;
+ }
+ started_tr = 1;
+ }
+
+ /*
+ * Reserve some space in the Catalog file.
+ */
+ if ((error = cat_preflight(hfsmp, CAT_DELETE, &cookie, p))) {
+ goto out;
+ }
+ cat_reserve = 1;
+
+ lockflags = hfs_systemfile_lock(hfsmp, SFL_CATALOG | SFL_ATTRIBUTE, HFS_EXCLUSIVE_LOCK);
+
+ if (cp->c_blocks > 0) {
+ printf("hfs_inactive: deleting non-empty%sfile %d, "
+ "blks %d\n", VNODE_IS_RSRC(vp) ? " rsrc " : " ",
+ (int)cp->c_fileid, (int)cp->c_blocks);
+ }
- /*
- * Reserve some space in the Catalog file.
- */
- if ((error = cat_preflight(hfsmp, CAT_DELETE, &cookie, p))) {
- goto out;
- }
- cat_reserve = 1;
-
- lockflags = hfs_systemfile_lock(hfsmp, SFL_CATALOG | SFL_ATTRIBUTE, HFS_EXCLUSIVE_LOCK);
-
- if (cp->c_blocks > 0)
- printf("hfs_inactive: attempting to delete a non-empty file!");
-
-
- //
- // release the name pointer in the descriptor so that
- // cat_delete() will use the file-id to do the deletion.
- // in the case of hard links this is imperative (in the
- // case of regular files the fileid and cnid are the
- // same so it doesn't matter).
//
- cat_releasedesc(&cp->c_desc);
+ // release the name pointer in the descriptor so that
+ // cat_delete() will use the file-id to do the deletion.
+ // in the case of hard links this is imperative (in the
+ // case of regular files the fileid and cnid are the
+ // same so it doesn't matter).
+ //
+ cat_releasedesc(&cp->c_desc);
- /*
- * The descriptor name may be zero,
- * in which case the fileid is used.
- */
- error = cat_delete(hfsmp, &cp->c_desc, &cp->c_attr);
+ /*
+ * The descriptor name may be zero,
+ * in which case the fileid is used.
+ */
+ error = cat_delete(hfsmp, &cp->c_desc, &cp->c_attr);
- if (error && truncated && (error != ENXIO))
- printf("hfs_inactive: couldn't delete a truncated file!");
-
- /* Update HFS Private Data dir */
- if (error == 0) {
- hfsmp->hfs_privdir_attr.ca_entries--;
- (void)cat_update(hfsmp, &hfsmp->hfs_privdir_desc,
- &hfsmp->hfs_privdir_attr, NULL, NULL);
- }
-
- if (error == 0) {
- /* Delete any attributes, ignore errors */
- (void) hfs_removeallattr(hfsmp, cp->c_fileid);
- }
-
- hfs_systemfile_unlock(hfsmp, lockflags);
-
- if (error)
+ if (error && truncated && (error != ENXIO))
+ printf("hfs_inactive: couldn't delete a truncated file!");
+
+ /* Update HFS Private Data dir */
+ if (error == 0) {
+ hfsmp->hfs_private_attr[FILE_HARDLINKS].ca_entries--;
+ if (vnode_isdir(vp)) {
+ DEC_FOLDERCOUNT(hfsmp, hfsmp->hfs_private_attr[FILE_HARDLINKS]);
+ }
+ (void)cat_update(hfsmp, &hfsmp->hfs_private_desc[FILE_HARDLINKS],
+ &hfsmp->hfs_private_attr[FILE_HARDLINKS], NULL, NULL);
+ }
+
+ hfs_systemfile_unlock(hfsmp, lockflags);
+
+ if (error) {
goto out;
-
+ }
+
#if QUOTA
- (void)hfs_chkiq(cp, -1, NOCRED, 0);
+ if (hfsmp->hfs_flags & HFS_QUOTAS)
+ (void)hfs_chkiq(cp, -1, NOCRED, 0);
#endif /* QUOTA */
-
- cp->c_mode = 0;
- cp->c_flag |= C_NOEXISTS;
- cp->c_touch_chgtime = TRUE;
- cp->c_touch_modtime = TRUE;
-
- if (error == 0)
- hfs_volupdate(hfsmp, VOL_RMFILE, 0);
- }
-
- if ((cp->c_flag & C_MODIFIED) ||
- cp->c_touch_acctime || cp->c_touch_chgtime || cp->c_touch_modtime) {
- hfs_update(vp, 0);
- }
+
+ /* Already set C_NOEXISTS at the beginning of this block */
+ cp->c_flag &= ~C_DELETED;
+ cp->c_touch_chgtime = TRUE;
+ cp->c_touch_modtime = TRUE;
+
+ if (error == 0)
+ hfs_volupdate(hfsmp, (v_type == VDIR) ? VOL_RMDIR : VOL_RMFILE, 0);
+ }
+
+ /*
+ * A file may have had delayed allocations, in which case hfs_update
+ * would not have updated the catalog record (cat_update). We need
+ * to do that now, before we lose our fork data. We also need to
+ * force the update, or hfs_update will again skip the cat_update.
+ *
+ * If the file has C_NOEXISTS set, then we can skip the hfs_update call
+ * because the catalog entry has already been removed. There would be no point
+ * to looking up the entry in the catalog to modify it when we already know it's gone
+ */
+ if ((!ISSET(cp->c_flag, C_NOEXISTS)) &&
+ ((cp->c_flag & C_MODIFIED) || cp->c_touch_acctime ||
+ cp->c_touch_chgtime || cp->c_touch_modtime)) {
+
+ if ((cp->c_flag & C_MODIFIED) || cp->c_touch_modtime){
+ cp->c_flag |= C_FORCEUPDATE;
+ }
+ hfs_update(vp, 0);
+ }
+
out:
- if (cat_reserve)
- cat_postflight(hfsmp, &cookie, p);
+ if (cat_reserve)
+ cat_postflight(hfsmp, &cookie, p);
+
+ // XXXdbg - have to do this because a goto could have come here
+ if (started_tr) {
+ hfs_end_transaction(hfsmp);
+ started_tr = 0;
+ }
+
+
+ return error;
+}
- // XXXdbg - have to do this because a goto could have come here
- if (started_tr) {
- hfs_end_transaction(hfsmp);
- started_tr = 0;
- }
- hfs_unlock(cp);
- if (took_trunc_lock)
- hfs_unlock_truncate(cp);
+/*
+ * hfs_vnop_inactive
+ *
+ * The last usecount on the vnode has gone away, so we need to tear down
+ * any remaining data still residing in the cnode. If necessary, write out
+ * remaining blocks or delete the cnode's entry in the catalog.
+ */
+int
+hfs_vnop_inactive(struct vnop_inactive_args *ap)
+{
+ struct vnode *vp = ap->a_vp;
+ struct cnode *cp;
+ struct hfsmount *hfsmp = VTOHFS(vp);
+ struct proc *p = vfs_context_proc(ap->a_context);
+ int error = 0;
+ int took_trunc_lock = 0;
+ enum vtype v_type;
+
+ v_type = vnode_vtype(vp);
+ cp = VTOC(vp);
+ if ((hfsmp->hfs_flags & HFS_READ_ONLY) || vnode_issystem(vp) ||
+ (hfsmp->hfs_freezing_proc == p)) {
+ error = 0;
+ goto inactive_done;
+ }
+
/*
- * If we are done with the vnode, reclaim it
- * so that it can be reused immediately.
+ * For safety, do NOT call vnode_recycle from inside this function. This can cause
+ * problems in the following scenario:
+ *
+ * vnode_create -> vnode_reclaim_internal -> vclean -> VNOP_INACTIVE
+ *
+ * If we're being invoked as a result of a reclaim that was already in-flight, then we
+ * cannot call vnode_recycle again. Being in reclaim means that there are no usecounts or
+ * iocounts by definition. As a result, if we were to call vnode_recycle, it would immediately
+ * try to re-enter reclaim again and panic.
+ *
+ * Currently, there are three things that can cause us (VNOP_INACTIVE) to get called.
+ * 1) last usecount goes away on the vnode (vnode_rele)
+ * 2) last iocount goes away on a vnode that previously had usecounts but didn't have
+ * vnode_recycle called (vnode_put)
+ * 3) vclean by way of reclaim
+ *
+ * In this function we would generally want to call vnode_recycle to speed things
+ * along to ensure that we don't leak blocks due to open-unlinked files. However, by
+ * virtue of being in this function already, we can call hfs_cnode_teardown, which
+ * will release blocks held by open-unlinked files, and mark them C_NOEXISTS so that
+ * there's no entry in the catalog and no backing store anymore. If that's the case,
+ * then we really don't care all that much when the vnode actually goes through reclaim.
+ * Further, the HFS VNOPs that manipulated the namespace in order to create the open-
+ * unlinked file in the first place should have already called vnode_recycle on the vnode
+ * to guarantee that it would go through reclaim in a speedy way.
*/
- if (cp->c_mode == 0 || recycle)
- vnode_recycle(vp);
-
- return (error);
+
+ if (cp->c_flag & C_NOEXISTS) {
+ /*
+ * If the cnode has already had its cat entry removed, then
+ * just skip to the end. We don't need to do anything here.
+ */
+ error = 0;
+ goto inactive_done;
+ }
+
+ if ((v_type == VREG || v_type == VLNK)) {
+ hfs_lock_truncate(cp, HFS_EXCLUSIVE_LOCK);
+ took_trunc_lock = 1;
+ }
+
+ (void) hfs_lock(cp, HFS_FORCE_LOCK);
+
+ /*
+ * Call cnode_teardown to push out dirty blocks to disk, release open-unlinked
+ * files' blocks from being in use, and move the cnode from C_DELETED to C_NOEXISTS.
+ */
+ error = hfs_cnode_teardown (vp, ap->a_context, 0);
+
+ /*
+ * Drop the truncate lock before unlocking the cnode
+ * (which can potentially perform a vnode_put and
+ * recycle the vnode which in turn might require the
+ * truncate lock)
+ */
+ if (took_trunc_lock) {
+ hfs_unlock_truncate(cp, 0);
+ }
+
+ hfs_unlock(cp);
+
+inactive_done:
+
+ return error;
}
+
/*
* File clean-up (zero fill and shrink peof).
*/
-static int
+
+int
hfs_filedone(struct vnode *vp, vfs_context_t context)
{
struct cnode *cp;
struct filefork *fp;
struct hfsmount *hfsmp;
+ struct rl_entry *invalid_range;
off_t leof;
- u_long blks, blocksize;
+ u_int32_t blks, blocksize;
+ int cluster_flags = IO_CLOSE;
+ int cluster_zero_flags = IO_HEADZEROFILL | IO_NOZERODIRTY | IO_NOCACHE;
cp = VTOC(vp);
fp = VTOF(vp);
if ((hfsmp->hfs_flags & HFS_READ_ONLY) || (fp->ff_blocks == 0))
return (0);
+ /*
+ * If we are being invoked from F_SWAPDATAEXTENTS, then we
+ * need to issue synchronous IO; Unless we are sure that all
+ * of the data has been written to the disk, we won't know
+ * that all of the blocks have been allocated properly.
+ */
+ if (cp->c_flag & C_SWAPINPROGRESS) {
+ cluster_flags |= IO_SYNC;
+ }
+
hfs_unlock(cp);
- (void) cluster_push(vp, IO_CLOSE);
+ (void) cluster_push(vp, cluster_flags);
hfs_lock(cp, HFS_FORCE_LOCK);
/*
* Explicitly zero out the areas of file
* that are currently marked invalid.
*/
- while (!CIRCLEQ_EMPTY(&fp->ff_invalidranges)) {
- struct rl_entry *invalid_range = CIRCLEQ_FIRST(&fp->ff_invalidranges);
+ while ((invalid_range = TAILQ_FIRST(&fp->ff_invalidranges))) {
off_t start = invalid_range->rl_start;
off_t end = invalid_range->rl_end;
hfs_unlock(cp);
(void) cluster_write(vp, (struct uio *) 0,
- leof, end + 1, start, (off_t)0,
- IO_HEADZEROFILL | IO_NOZERODIRTY | IO_NOCACHE);
+ leof, end + 1, start, (off_t)0, cluster_zero_flags);
hfs_lock(cp, HFS_FORCE_LOCK);
cp->c_flag |= C_MODIFIED;
}
* Shrink the peof to the smallest size neccessary to contain the leof.
*/
if (blks < fp->ff_blocks)
- (void) hfs_truncate(vp, leof, IO_NDELAY, 0, context);
+ (void) hfs_truncate(vp, leof, IO_NDELAY, 0, 0, context);
hfs_unlock(cp);
- (void) cluster_push(vp, IO_CLOSE);
+ (void) cluster_push(vp, cluster_flags);
hfs_lock(cp, HFS_FORCE_LOCK);
/*
/*
* Reclaim a cnode so that it can be used for other purposes.
*/
-__private_extern__
int
hfs_vnop_reclaim(struct vnop_reclaim_args *ap)
{
struct cnode *cp;
struct filefork *fp = NULL;
struct filefork *altfp = NULL;
+ struct hfsmount *hfsmp = VTOHFS(vp);
+ vfs_context_t ctx = ap->a_context;
int reclaim_cnode = 0;
-
- (void) hfs_lock(VTOC(vp), HFS_FORCE_LOCK);
+ int err = 0;
+ enum vtype v_type;
+
+ v_type = vnode_vtype(vp);
cp = VTOC(vp);
+
+ /*
+ * We don't take the truncate lock since by the time reclaim comes along,
+ * all dirty pages have been synced and nobody should be competing
+ * with us for this thread.
+ */
+ (void) hfs_lock (cp, HFS_FORCE_LOCK);
+
+ /*
+ * Sync to disk any remaining data in the cnode/vnode. This includes
+ * a call to hfs_update if the cnode has outbound data.
+ *
+ * If C_NOEXISTS is set on the cnode, then there's nothing teardown needs to do
+ * because the catalog entry for this cnode is already gone.
+ */
+ if (!ISSET(cp->c_flag, C_NOEXISTS)) {
+ err = hfs_cnode_teardown(vp, ctx, 1);
+ }
/*
* Keep track of an inactive hot file.
*/
- if (!vnode_isdir(vp) && !vnode_issystem(vp))
+ if (!vnode_isdir(vp) &&
+ !vnode_issystem(vp) &&
+ !(cp->c_flag & (C_DELETED | C_NOEXISTS)) ) {
(void) hfs_addhotfile(vp);
-
+ }
vnode_removefsref(vp);
/*
cp->c_rsrcfork = NULL;
cp->c_rsrc_vp = NULL;
} else {
- panic("hfs_vnop_reclaim: vp points to wrong cnode\n");
+ panic("hfs_vnop_reclaim: vp points to wrong cnode (vp=%p cp->c_vp=%p cp->c_rsrc_vp=%p)\n", vp, cp->c_vp, cp->c_rsrc_vp);
}
/*
* On the last fork, remove the cnode from its hash chain.
*/
if (altfp == NULL) {
/* If we can't remove it then the cnode must persist! */
- if (hfs_chashremove(cp) == 0)
+ if (hfs_chashremove(hfsmp, cp) == 0)
reclaim_cnode = 1;
/*
* Remove any directory hints
if (vnode_isdir(vp)) {
hfs_reldirhints(cp, 0);
}
+
+ if(cp->c_flag & C_HARDLINK) {
+ hfs_relorigins(cp);
+ }
}
/* Release the file fork and related data */
if (fp) {
* If there was only one active fork then we can release the cnode.
*/
if (reclaim_cnode) {
- hfs_chashwakeup(cp, H_ALLOC | H_TRANSIT);
+ hfs_chashwakeup(hfsmp, cp, H_ALLOC | H_TRANSIT);
hfs_reclaim_cnode(cp);
- } else /* cnode in use */ {
+ }
+ else {
+ /*
+ * cnode in use. If it is a directory, it could have
+ * no live forks. Just release the lock.
+ */
hfs_unlock(cp);
}
extern int (**hfs_vnodeop_p) (void *);
+extern int (**hfs_std_vnodeop_p) (void *);
extern int (**hfs_specop_p) (void *);
+#if FIFO
extern int (**hfs_fifoop_p) (void *);
+#endif
/*
* hfs_getnewvnode - get new default vnode
*
* The vnode is returned with an iocount and the cnode locked
*/
-__private_extern__
int
hfs_getnewvnode(
struct hfsmount *hfsmp,
struct vnode *dvp,
struct componentname *cnp,
struct cat_desc *descp,
- int wantrsrc,
+ int flags,
struct cat_attr *attrp,
struct cat_fork *forkp,
- struct vnode **vpp)
+ struct vnode **vpp,
+ int *out_flags)
{
struct mount *mp = HFSTOVFS(hfsmp);
struct vnode *vp = NULL;
struct vnode *tvp = NULLVP;
struct cnode *cp = NULL;
struct filefork *fp = NULL;
- int i;
+ int hfs_standard = 0;
int retval;
int issystemfile;
+ int wantrsrc;
+ int hflags = 0;
struct vnode_fsparam vfsp;
enum vtype vtype;
+#if QUOTA
+ int i;
+#endif /* QUOTA */
+
+ hfs_standard = (hfsmp->hfs_flags & HFS_STANDARD);
if (attrp->ca_fileid == 0) {
*vpp = NULL;
*vpp = NULL;
return (ENOTSUP);
}
-#endif
+#endif /* !FIFO */
vtype = IFTOVT(attrp->ca_mode);
issystemfile = (descp->cd_flags & CD_ISMETA) && (vtype == VREG);
+ wantrsrc = flags & GNV_WANTRSRC;
+
+ /* Zero out the out_flags */
+ *out_flags = 0;
+
+#ifdef HFS_CHECK_LOCK_ORDER
+ /*
+ * The only case were its permissible to hold the parent cnode
+ * lock is during a create operation (hfs_makenode) or when
+ * we don't need the cnode lock (GNV_SKIPLOCK).
+ */
+ if ((dvp != NULL) &&
+ (flags & (GNV_CREATE | GNV_SKIPLOCK)) == 0 &&
+ VTOC(dvp)->c_lockowner == current_thread()) {
+ panic("hfs_getnewvnode: unexpected hold of parent cnode %p", VTOC(dvp));
+ }
+#endif /* HFS_CHECK_LOCK_ORDER */
/*
* Get a cnode (new or existing)
- * skip getting the cnode lock if we are getting resource fork (wantrsrc == 2)
*/
- cp = hfs_chash_getcnode(hfsmp->hfs_raw_dev, attrp->ca_fileid, vpp, wantrsrc, (wantrsrc == 2));
+ cp = hfs_chash_getcnode(hfsmp, attrp->ca_fileid, vpp, wantrsrc,
+ (flags & GNV_SKIPLOCK), out_flags, &hflags);
- /* Hardlinks may need an updated catalog descriptor */
- if ((cp->c_flag & C_HARDLINK) && descp->cd_nameptr && descp->cd_namelen > 0) {
- replace_desc(cp, descp);
+ /*
+ * If the id is no longer valid for lookups we'll get back a NULL cp.
+ */
+ if (cp == NULL) {
+ return (ENOENT);
}
+
+ /*
+ * If we get a cnode/vnode pair out of hfs_chash_getcnode, then update the
+ * descriptor in the cnode as needed if the cnode represents a hardlink.
+ * We want the caller to get the most up-to-date copy of the descriptor
+ * as possible. However, we only do anything here if there was a valid vnode.
+ * If there isn't a vnode, then the cnode is brand new and needs to be initialized
+ * as it doesn't have a descriptor or cat_attr yet.
+ *
+ * If we are about to replace the descriptor with the user-supplied one, then validate
+ * that the descriptor correctly acknowledges this item is a hardlink. We could be
+ * subject to a race where the calling thread invoked cat_lookup, got a valid lookup
+ * result but the file was not yet a hardlink. With sufficient delay between there
+ * and here, we might accidentally copy in the raw inode ID into the descriptor in the
+ * call below. If the descriptor's CNID is the same as the fileID then it must
+ * not yet have been a hardlink when the lookup occurred.
+ */
+
+ if (!(hfs_checkdeleted(cp))) {
+ if ((cp->c_flag & C_HARDLINK) && descp->cd_nameptr && descp->cd_namelen > 0) {
+ /* If cnode is uninitialized, its c_attr will be zeroed out; cnids wont match. */
+ if ((descp->cd_cnid == cp->c_attr.ca_fileid) &&
+ (attrp->ca_linkcount != cp->c_attr.ca_linkcount)){
+ if ((flags & GNV_SKIPLOCK) == 0) {
+ /*
+ * Then we took the lock. Drop it before calling
+ * vnode_put, which may invoke hfs_vnop_inactive and need to take
+ * the cnode lock again.
+ */
+ hfs_unlock(cp);
+ }
+
+ /*
+ * Emit ERECYCLE and GNV_CAT_ATTRCHANGED to
+ * force a re-drive in the lookup routine.
+ * Drop the iocount on the vnode obtained from
+ * chash_getcnode if needed.
+ */
+ if (*vpp != NULL) {
+ vnode_put (*vpp);
+ *vpp = NULL;
+ }
+
+ /*
+ * If we raced with VNOP_RECLAIM for this vnode, the hash code could
+ * have observed it after the c_vp or c_rsrc_vp fields had been torn down;
+ * the hash code peeks at those fields without holding the cnode lock because
+ * it needs to be fast. As a result, we may have set H_ATTACH in the chash
+ * call above. Since we're bailing out, unset whatever flags we just set, and
+ * wake up all waiters for this cnode.
+ */
+ if (hflags) {
+ hfs_chashwakeup(hfsmp, cp, hflags);
+ }
+
+ *out_flags = GNV_CAT_ATTRCHANGED;
+ return ERECYCLE;
+ }
+ else {
+ /* Otherwise, CNID != fileid. Go ahead and copy in the new descriptor */
+ replace_desc(cp, descp);
+ }
+ }
+ }
+
+
/* Check if we found a matching vnode */
- if (*vpp != NULL)
+ if (*vpp != NULL) {
return (0);
+ }
/*
* If this is a new cnode then initialize it.
*/
if (ISSET(cp->c_hflag, H_ALLOC)) {
lck_rw_init(&cp->c_truncatelock, hfs_rwlock_group, hfs_lock_attr);
+#if HFS_COMPRESSION
+ cp->c_decmp = NULL;
+#endif
/* Make sure its still valid (ie exists on disk). */
- if (!hfs_valid_cnode(hfsmp, dvp, (wantrsrc ? NULL : cnp), cp->c_fileid)) {
- hfs_chash_abort(cp);
- hfs_reclaim_cnode(cp);
- *vpp = NULL;
- return (ENOENT);
+ if (!(flags & GNV_CREATE)) {
+ int error = 0;
+ if (!hfs_valid_cnode (hfsmp, dvp, (wantrsrc ? NULL : cnp), cp->c_fileid, attrp, &error)) {
+ hfs_chash_abort(hfsmp, cp);
+ hfs_reclaim_cnode(cp);
+ *vpp = NULL;
+ /*
+ * If we hit this case, that means that the entry was there in the catalog when
+ * we did a cat_lookup earlier. Think hfs_lookup. However, in between the time
+ * that we checked the catalog and the time we went to get a vnode/cnode for it,
+ * it had been removed from the namespace and the vnode totally reclaimed. As a result,
+ * it's not there in the catalog during the check in hfs_valid_cnode and we bubble out
+ * an ENOENT. To indicate to the caller that they should really double-check the
+ * entry (it could have been renamed over and gotten a new fileid), we mark a bit
+ * in the output flags.
+ */
+ if (error == ENOENT) {
+ *out_flags = GNV_CAT_DELETED;
+ return ENOENT;
+ }
+
+ /*
+ * Also, we need to protect the cat_attr acquired during hfs_lookup and passed into
+ * this function as an argument because the catalog may have changed w.r.t hardlink
+ * link counts and the firstlink field. If that validation check fails, then let
+ * lookup re-drive itself to get valid/consistent data with the same failure condition below.
+ */
+ if (error == ERECYCLE) {
+ *out_flags = GNV_CAT_ATTRCHANGED;
+ return (ERECYCLE);
+ }
+ }
}
bcopy(attrp, &cp->c_attr, sizeof(struct cat_attr));
bcopy(descp, &cp->c_desc, sizeof(struct cat_desc));
descp->cd_flags &= ~CD_HASBUF;
/* Tag hardlinks */
- if (IFTOVT(cp->c_mode) == VREG &&
- (descp->cd_cnid != attrp->ca_fileid)) {
+ if ((vtype == VREG || vtype == VDIR) &&
+ ((descp->cd_cnid != attrp->ca_fileid) ||
+ (attrp->ca_recflags & kHFSHasLinkChainMask))) {
cp->c_flag |= C_HARDLINK;
}
+ /*
+ * Fix-up dir link counts.
+ *
+ * Earlier versions of Leopard used ca_linkcount for posix
+ * nlink support (effectively the sub-directory count + 2).
+ * That is now accomplished using the ca_dircount field with
+ * the corresponding kHFSHasFolderCountMask flag.
+ *
+ * For directories the ca_linkcount is the true link count,
+ * tracking the number of actual hardlinks to a directory.
+ *
+ * We only do this if the mount has HFS_FOLDERCOUNT set;
+ * at the moment, we only set that for HFSX volumes.
+ */
+ if ((hfsmp->hfs_flags & HFS_FOLDERCOUNT) &&
+ (vtype == VDIR) &&
+ !(attrp->ca_recflags & kHFSHasFolderCountMask) &&
+ (cp->c_attr.ca_linkcount > 1)) {
+ if (cp->c_attr.ca_entries == 0)
+ cp->c_attr.ca_dircount = 0;
+ else
+ cp->c_attr.ca_dircount = cp->c_attr.ca_linkcount - 2;
- /* Take one dev reference for each non-directory cnode */
- if (IFTOVT(cp->c_mode) != VDIR) {
- cp->c_devvp = hfsmp->hfs_devvp;
- vnode_ref(cp->c_devvp);
+ cp->c_attr.ca_linkcount = 1;
+ cp->c_attr.ca_recflags |= kHFSHasFolderCountMask;
+ if ( !(hfsmp->hfs_flags & HFS_READ_ONLY) )
+ cp->c_flag |= C_MODIFIED;
}
#if QUOTA
- for (i = 0; i < MAXQUOTAS; i++)
- cp->c_dquot[i] = NODQUOT;
+ if (hfsmp->hfs_flags & HFS_QUOTAS) {
+ for (i = 0; i < MAXQUOTAS; i++)
+ cp->c_dquot[i] = NODQUOT;
+ }
#endif /* QUOTA */
+ /* Mark the output flag that we're vending a new cnode */
+ *out_flags |= GNV_NEW_CNODE;
}
- if (IFTOVT(cp->c_mode) == VDIR) {
+ if (vtype == VDIR) {
if (cp->c_vp != NULL)
panic("hfs_getnewvnode: orphaned vnode (data)");
cvpp = &cp->c_vp;
vfsp.vnfs_mp = mp;
vfsp.vnfs_vtype = vtype;
vfsp.vnfs_str = "hfs";
- vfsp.vnfs_dvp = dvp;
+ if ((cp->c_flag & C_HARDLINK) && (vtype == VDIR)) {
+ vfsp.vnfs_dvp = NULL; /* no parent for me! */
+ vfsp.vnfs_cnp = NULL; /* no name for me! */
+ } else {
+ vfsp.vnfs_dvp = dvp;
+ vfsp.vnfs_cnp = cnp;
+ }
vfsp.vnfs_fsnode = cp;
- vfsp.vnfs_cnp = cnp;
- if (vtype == VFIFO )
+
+ /*
+ * Special Case HFS Standard VNOPs from HFS+, since
+ * HFS standard is readonly/deprecated as of 10.6
+ */
+
+#if FIFO
+ if (vtype == VFIFO )
vfsp.vnfs_vops = hfs_fifoop_p;
- else if (vtype == VBLK || vtype == VCHR)
- vfsp.vnfs_vops = hfs_specop_p;
else
+#endif
+ if (vtype == VBLK || vtype == VCHR)
+ vfsp.vnfs_vops = hfs_specop_p;
+ else if (hfs_standard)
+ vfsp.vnfs_vops = hfs_std_vnodeop_p;
+ else
vfsp.vnfs_vops = hfs_vnodeop_p;
-
+
if (vtype == VBLK || vtype == VCHR)
vfsp.vnfs_rdev = attrp->ca_rdev;
else
else
vfsp.vnfs_filesize = 0;
- if (dvp && cnp && (cnp->cn_flags & MAKEENTRY))
- vfsp.vnfs_flags = 0;
- else
- vfsp.vnfs_flags = VNFS_NOCACHE;
+ vfsp.vnfs_flags = VNFS_ADDFSREF;
+ if (dvp == NULLVP || cnp == NULL || !(cnp->cn_flags & MAKEENTRY) || (flags & GNV_NOCACHE))
+ vfsp.vnfs_flags |= VNFS_NOCACHE;
/* Tag system files */
vfsp.vnfs_marksystem = issystemfile;
* occurred during the attachment, then cleanup the cnode.
*/
if ((cp->c_vp == NULL) && (cp->c_rsrc_vp == NULL)) {
- hfs_chash_abort(cp);
+ hfs_chash_abort(hfsmp, cp);
hfs_reclaim_cnode(cp);
- } else {
- hfs_chashwakeup(cp, H_ALLOC | H_ATTACH);
- hfs_unlock(cp);
+ }
+ else {
+ hfs_chashwakeup(hfsmp, cp, H_ALLOC | H_ATTACH);
+ if ((flags & GNV_SKIPLOCK) == 0){
+ hfs_unlock(cp);
+ }
}
*vpp = NULL;
return (retval);
}
vp = *cvpp;
- vnode_addfsref(vp);
vnode_settag(vp, VT_HFS);
- if (cp->c_flag & C_HARDLINK)
- vnode_set_hard_link(vp);
- hfs_chashwakeup(cp, H_ALLOC | H_ATTACH);
+ if (cp->c_flag & C_HARDLINK) {
+ vnode_setmultipath(vp);
+ }
+ /*
+ * Tag resource fork vnodes as needing an VNOP_INACTIVE
+ * so that any deferred removes (open unlinked files)
+ * have the chance to process the resource fork.
+ */
+ if (VNODE_IS_RSRC(vp)) {
+ int err;
+ KERNEL_DEBUG_CONSTANT((FSDBG_CODE(DBG_FSRW, 37)), cp->c_vp, cp->c_rsrc_vp, 0, 0, 0);
+
+ /* Force VL_NEEDINACTIVE on this vnode */
+ err = vnode_ref(vp);
+ if (err == 0) {
+ vnode_rele(vp);
+ }
+ }
+ hfs_chashwakeup(hfsmp, cp, H_ALLOC | H_ATTACH);
/*
* Stop tracking an active hot file.
*/
- if (!vnode_isdir(vp) && !vnode_issystem(vp))
+ if (!(flags & GNV_CREATE) && (vtype != VDIR) && !issystemfile) {
(void) hfs_removehotfile(vp);
+ }
+
+#if CONFIG_PROTECT
+ if (!issystemfile && (*out_flags & GNV_NEW_CNODE))
+ cp_entry_init(cp, mp);
+#endif
*vpp = vp;
return (0);
}
#endif /* QUOTA */
- if (cp->c_devvp) {
- struct vnode *tmp_vp = cp->c_devvp;
-
- cp->c_devvp = NULL;
- vnode_rele(tmp_vp);
- }
-
/*
* If the descriptor has a name then release it
*/
- if (cp->c_desc.cd_flags & CD_HASBUF) {
- char *nameptr;
+ if ((cp->c_desc.cd_flags & CD_HASBUF) && (cp->c_desc.cd_nameptr != 0)) {
+ const char *nameptr;
- nameptr = cp->c_desc.cd_nameptr;
+ nameptr = (const char *) cp->c_desc.cd_nameptr;
cp->c_desc.cd_nameptr = 0;
cp->c_desc.cd_flags &= ~CD_HASBUF;
cp->c_desc.cd_namelen = 0;
vfs_removename(nameptr);
}
-
+
+ /*
+ * We only call this function if we are in hfs_vnop_reclaim and
+ * attempting to reclaim a cnode with only one live fork. Because the vnode
+ * went through reclaim, any future attempts to use this item will have to
+ * go through lookup again, which will need to create a new vnode. Thus,
+ * destroying the locks below (while they were still held during our parent
+ * function hfs_vnop_reclaim) is safe.
+ */
+
lck_rw_destroy(&cp->c_rwlock, hfs_rwlock_group);
lck_rw_destroy(&cp->c_truncatelock, hfs_rwlock_group);
+#if HFS_COMPRESSION
+ if (cp->c_decmp) {
+ decmpfs_cnode_destroy(cp->c_decmp);
+ FREE_ZONE(cp->c_decmp, sizeof(*(cp->c_decmp)), M_DECMPFS_CNODE);
+ }
+#endif
+#if CONFIG_PROTECT
+ cp_entry_destroy(cp);
+#endif
+
+
bzero(cp, sizeof(struct cnode));
FREE_ZONE(cp, sizeof(struct cnode), M_HFSNODE);
}
-static int
-hfs_valid_cnode(struct hfsmount *hfsmp, struct vnode *dvp, struct componentname *cnp, cnid_t cnid)
+/*
+ * hfs_valid_cnode
+ *
+ * This function is used to validate data that is stored in-core against what is contained
+ * in the catalog. Common uses include validating that the parent-child relationship still exist
+ * for a specific directory entry (guaranteeing it has not been renamed into a different spot) at
+ * the point of the check.
+ */
+int
+hfs_valid_cnode(struct hfsmount *hfsmp, struct vnode *dvp, struct componentname *cnp,
+ cnid_t cnid, struct cat_attr *cattr, int *error)
{
struct cat_attr attr;
struct cat_desc cndesc;
int lockflags;
/* System files are always valid */
- if (cnid < kHFSFirstUserCatalogNodeID)
+ if (cnid < kHFSFirstUserCatalogNodeID) {
+ *error = 0;
return (1);
+ }
/* XXX optimization: check write count in dvp */
lockflags = hfs_systemfile_lock(hfsmp, SFL_CATALOG, HFS_SHARED_LOCK);
if (dvp && cnp) {
+ int lookup = 0;
+ struct cat_fork fork;
+
bzero(&cndesc, sizeof(cndesc));
- cndesc.cd_nameptr = cnp->cn_nameptr;
+ cndesc.cd_nameptr = (const u_int8_t *)cnp->cn_nameptr;
cndesc.cd_namelen = cnp->cn_namelen;
- cndesc.cd_parentcnid = VTOC(dvp)->c_cnid;
+ cndesc.cd_parentcnid = VTOC(dvp)->c_fileid;
cndesc.cd_hint = VTOC(dvp)->c_childhint;
- if ((cat_lookup(hfsmp, &cndesc, 0, NULL, &attr, NULL, NULL) == 0) &&
- (cnid == attr.ca_fileid)) {
+ /*
+ * We have to be careful when calling cat_lookup. The result argument
+ * 'attr' may get different results based on whether or not you ask
+ * for the filefork to be supplied as output. This is because cat_lookupbykey
+ * will attempt to do basic validation/smoke tests against the resident
+ * extents if there are no overflow extent records, but it needs someplace
+ * in memory to store the on-disk fork structures.
+ *
+ * Since hfs_lookup calls cat_lookup with a filefork argument, we should
+ * do the same here, to verify that block count differences are not
+ * due to calling the function with different styles. cat_lookupbykey
+ * will request the volume be fsck'd if there is true on-disk corruption
+ * where the number of blocks does not match the number generated by
+ * summing the number of blocks in the resident extents.
+ */
+
+ lookup = cat_lookup (hfsmp, &cndesc, 0, NULL, &attr, &fork, NULL);
+ if ((lookup == 0) && (cnid == attr.ca_fileid)) {
stillvalid = 1;
+ *error = 0;
+ }
+ else {
+ *error = ENOENT;
+ }
+
+ /*
+ * In hfs_getnewvnode, we may encounter a time-of-check vs. time-of-vnode creation
+ * race. Specifically, if there is no vnode/cnode pair for the directory entry
+ * being looked up, we have to go to the catalog. But since we don't hold any locks (aside
+ * from the dvp in 'shared' mode) there is nothing to protect us against the catalog record
+ * changing in between the time we do the cat_lookup there and the time we re-grab the
+ * catalog lock above to do another cat_lookup.
+ *
+ * However, we need to check more than just the CNID and parent-child name relationships above.
+ * Hardlinks can suffer the same race in the following scenario: Suppose we do a
+ * cat_lookup, and find a leaf record and a raw inode for a hardlink. Now, we have
+ * the cat_attr in hand (passed in above). But in between then and now, the vnode was
+ * created by a competing hfs_getnewvnode call, and is manipulated and reclaimed before we get
+ * a chance to do anything. This is possible if there are a lot of threads thrashing around
+ * with the cnode hash. In this case, if we don't check/validate the cat_attr in-hand, we will
+ * blindly stuff it into the cnode, which will make the in-core data inconsistent with what is
+ * on disk. So validate the cat_attr below, if required. This race cannot happen if the cnode/vnode
+ * already exists, as it does in the case of rename and delete.
+ */
+ if (stillvalid && cattr != NULL) {
+ if (cattr->ca_linkcount != attr.ca_linkcount) {
+ stillvalid = 0;
+ *error = ERECYCLE;
+ goto notvalid;
+ }
+
+ if (cattr->ca_union1.cau_linkref != attr.ca_union1.cau_linkref) {
+ stillvalid = 0;
+ *error = ERECYCLE;
+ goto notvalid;
+ }
+
+ if (cattr->ca_union3.cau_firstlink != attr.ca_union3.cau_firstlink) {
+ stillvalid = 0;
+ *error = ERECYCLE;
+ goto notvalid;
+ }
+
+ if (cattr->ca_union2.cau_blocks != attr.ca_union2.cau_blocks) {
+ stillvalid = 0;
+ *error = ERECYCLE;
+ goto notvalid;
+ }
}
} else {
- if (cat_idlookup(hfsmp, cnid, NULL, NULL, NULL) == 0) {
+ if (cat_idlookup(hfsmp, cnid, 0, NULL, NULL, NULL) == 0) {
stillvalid = 1;
+ *error = 0;
+ }
+ else {
+ *error = ENOENT;
}
}
+notvalid:
hfs_systemfile_unlock(hfsmp, lockflags);
return (stillvalid);
}
+/*
+ * Per HI and Finder requirements, HFS should add in the
+ * date/time that a particular directory entry was added
+ * to the containing directory.
+ * This is stored in the extended Finder Info for the
+ * item in question.
+ *
+ * Note that this field is also set explicitly in the hfs_vnop_setxattr code.
+ * We must ignore user attempts to set this part of the finderinfo, and
+ * so we need to save a local copy of the date added, write in the user
+ * finderinfo, then stuff the value back in.
+ */
+void hfs_write_dateadded (struct cat_attr *attrp, u_int32_t dateadded) {
+ u_int8_t *finfo = NULL;
+
+ /* overlay the FinderInfo to the correct pointer, and advance */
+ finfo = (u_int8_t*)attrp->ca_finderinfo;
+ finfo = finfo + 16;
+
+ /*
+ * Make sure to write it out as big endian, since that's how
+ * finder info is defined.
+ *
+ * NOTE: This is a Unix-epoch timestamp, not a HFS/Traditional Mac timestamp.
+ */
+ if (S_ISREG(attrp->ca_mode)) {
+ struct FndrExtendedFileInfo *extinfo = (struct FndrExtendedFileInfo *)finfo;
+ extinfo->date_added = OSSwapHostToBigInt32(dateadded);
+ attrp->ca_recflags |= kHFSHasDateAddedMask;
+ }
+ else if (S_ISDIR(attrp->ca_mode)) {
+ struct FndrExtendedDirInfo *extinfo = (struct FndrExtendedDirInfo *)finfo;
+ extinfo->date_added = OSSwapHostToBigInt32(dateadded);
+ attrp->ca_recflags |= kHFSHasDateAddedMask;
+ }
+
+ /* If it were neither directory/file, then we'd bail out */
+ return;
+}
+
+u_int32_t hfs_get_dateadded (struct cnode *cp) {
+ u_int8_t *finfo = NULL;
+ u_int32_t dateadded = 0;
+
+ if ((cp->c_attr.ca_recflags & kHFSHasDateAddedMask) == 0) {
+ /* Date added was never set. Return 0. */
+ return dateadded;
+ }
+
+
+ /* overlay the FinderInfo to the correct pointer, and advance */
+ finfo = (u_int8_t*)cp->c_finderinfo;
+ finfo = finfo + 16;
+
+ /*
+ * FinderInfo is written out in big endian... make sure to convert it to host
+ * native before we use it.
+ */
+ if (S_ISREG(cp->c_attr.ca_mode)) {
+ struct FndrExtendedFileInfo *extinfo = (struct FndrExtendedFileInfo *)finfo;
+ dateadded = OSSwapBigToHostInt32 (extinfo->date_added);
+ }
+ else if (S_ISDIR(cp->c_attr.ca_mode)) {
+ struct FndrExtendedDirInfo *extinfo = (struct FndrExtendedDirInfo *)finfo;
+ dateadded = OSSwapBigToHostInt32 (extinfo->date_added);
+ }
+
+ return dateadded;
+}
+
+
+
/*
* Touch cnode times based on c_touch_xxx flags
*
*
* This will also update the volume modify time
*/
-__private_extern__
void
hfs_touchtimes(struct hfsmount *hfsmp, struct cnode* cp)
{
+ vfs_context_t ctx;
+ /* don't modify times if volume is read-only */
+ if (hfsmp->hfs_flags & HFS_READ_ONLY) {
+ cp->c_touch_acctime = FALSE;
+ cp->c_touch_chgtime = FALSE;
+ cp->c_touch_modtime = FALSE;
+ return;
+ }
+ else if (hfsmp->hfs_flags & HFS_STANDARD) {
/* HFS Standard doesn't support access times */
- if (hfsmp->hfs_flags & HFS_STANDARD) {
cp->c_touch_acctime = FALSE;
}
- if (cp->c_touch_acctime || cp->c_touch_chgtime || cp->c_touch_modtime) {
+ ctx = vfs_context_current();
+ /*
+ * Skip access time updates if:
+ * . MNT_NOATIME is set
+ * . a file system freeze is in progress
+ * . a file system resize is in progress
+ * . the vnode associated with this cnode is marked for rapid aging
+ */
+ if (cp->c_touch_acctime) {
+ if ((vfs_flags(hfsmp->hfs_mp) & MNT_NOATIME) ||
+ (hfsmp->hfs_freezing_proc != NULL) ||
+ (hfsmp->hfs_flags & HFS_RESIZE_IN_PROGRESS) ||
+ (cp->c_vp && ((vnode_israge(cp->c_vp) || (vfs_ctx_skipatime(ctx)))))) {
+
+ cp->c_touch_acctime = FALSE;
+ }
+ }
+ if (cp->c_touch_acctime || cp->c_touch_chgtime ||
+ cp->c_touch_modtime || (cp->c_flag & C_NEEDS_DATEADDED)) {
struct timeval tv;
int touchvol = 0;
cp->c_flag |= C_MODIFIED;
touchvol = 1;
}
+
+ if (cp->c_flag & C_NEEDS_DATEADDED) {
+ hfs_write_dateadded (&(cp->c_attr), tv.tv_sec);
+ cp->c_flag |= C_MODIFIED;
+ /* untwiddle the bit */
+ cp->c_flag &= ~C_NEEDS_DATEADDED;
+ touchvol = 1;
+ }
/* Touch the volume modtime if needed */
if (touchvol) {
- HFSTOVCB(hfsmp)->vcbFlags |= 0xFF00;
+ MarkVCBDirty(hfsmp);
HFSTOVCB(hfsmp)->vcbLsMod = tv.tv_sec;
}
}
/*
* Lock a cnode.
*/
-__private_extern__
int
hfs_lock(struct cnode *cp, enum hfslocktype locktype)
{
void * thread = current_thread();
- /* System files need to keep track of owner */
- if ((cp->c_fileid < kHFSFirstUserCatalogNodeID) &&
- (cp->c_fileid > kHFSRootFolderID) &&
- (locktype != HFS_SHARED_LOCK)) {
-
+ if (cp->c_lockowner == thread) {
/*
- * The extents and bitmap file locks support
- * recursion and are always taken exclusive.
+ * Only the extents and bitmap file's support lock recursion.
*/
- if (cp->c_fileid == kHFSExtentsFileID ||
- cp->c_fileid == kHFSAllocationFileID) {
- if (cp->c_lockowner == thread) {
- cp->c_syslockcount++;
- } else {
- lck_rw_lock_exclusive(&cp->c_rwlock);
- cp->c_lockowner = thread;
- cp->c_syslockcount = 1;
- }
+ if ((cp->c_fileid == kHFSExtentsFileID) ||
+ (cp->c_fileid == kHFSAllocationFileID)) {
+ cp->c_syslockcount++;
} else {
- lck_rw_lock_exclusive(&cp->c_rwlock);
- cp->c_lockowner = thread;
+ panic("hfs_lock: locking against myself!");
}
} else if (locktype == HFS_SHARED_LOCK) {
lck_rw_lock_shared(&cp->c_rwlock);
cp->c_lockowner = HFS_SHARED_OWNER;
- } else {
+
+ } else /* HFS_EXCLUSIVE_LOCK */ {
lck_rw_lock_exclusive(&cp->c_rwlock);
cp->c_lockowner = thread;
+
+ /*
+ * Only the extents and bitmap file's support lock recursion.
+ */
+ if ((cp->c_fileid == kHFSExtentsFileID) ||
+ (cp->c_fileid == kHFSAllocationFileID)) {
+ cp->c_syslockcount = 1;
+ }
}
+
+#ifdef HFS_CHECK_LOCK_ORDER
+ /*
+ * Regular cnodes (non-system files) cannot be locked
+ * while holding the journal lock or a system file lock.
+ */
+ if (!(cp->c_desc.cd_flags & CD_ISMETA) &&
+ ((cp->c_fileid > kHFSFirstUserCatalogNodeID) || (cp->c_fileid == kHFSRootFolderID))) {
+ vnode_t vp = NULLVP;
+
+ /* Find corresponding vnode. */
+ if (cp->c_vp != NULLVP && VTOC(cp->c_vp) == cp) {
+ vp = cp->c_vp;
+ } else if (cp->c_rsrc_vp != NULLVP && VTOC(cp->c_rsrc_vp) == cp) {
+ vp = cp->c_rsrc_vp;
+ }
+ if (vp != NULLVP) {
+ struct hfsmount *hfsmp = VTOHFS(vp);
+
+ if (hfsmp->jnl && (journal_owner(hfsmp->jnl) == thread)) {
+ /* This will eventually be a panic here. */
+ printf("hfs_lock: bad lock order (cnode after journal)\n");
+ }
+ if (hfsmp->hfs_catalog_cp && hfsmp->hfs_catalog_cp->c_lockowner == thread) {
+ panic("hfs_lock: bad lock order (cnode after catalog)");
+ }
+ if (hfsmp->hfs_attribute_cp && hfsmp->hfs_attribute_cp->c_lockowner == thread) {
+ panic("hfs_lock: bad lock order (cnode after attribute)");
+ }
+ if (hfsmp->hfs_extents_cp && hfsmp->hfs_extents_cp->c_lockowner == thread) {
+ panic("hfs_lock: bad lock order (cnode after extents)");
+ }
+ }
+ }
+#endif /* HFS_CHECK_LOCK_ORDER */
+
/*
* Skip cnodes that no longer exist (were deleted).
*/
/*
* Lock a pair of cnodes.
*/
-__private_extern__
int
hfs_lockpair(struct cnode *cp1, struct cnode *cp2, enum hfslocktype locktype)
{
}
/*
- * Lock in cnode parent-child order (if there is a relationship);
- * otherwise lock in cnode address order.
+ * Lock in cnode address order.
*/
- if ((IFTOVT(cp1->c_mode) == VDIR) && (cp1->c_fileid == cp2->c_parentcnid)) {
- first = cp1;
- last = cp2;
- } else if (cp1 < cp2) {
+ if (cp1 < cp2) {
first = cp1;
last = cp2;
} else {
return (1);
if (cp2 == NULL || cp1 == (struct cnode *)0xffffffff)
return (0);
- if (cp1->c_fileid == cp2->c_parentcnid)
- return (1); /* cp1 is the parent and should go first */
- if (cp2->c_fileid == cp1->c_parentcnid)
- return (0); /* cp1 is the child and should go last */
-
- return (cp1 < cp2); /* fall-back is to use address order */
+ /*
+ * Locking order is cnode address order.
+ */
+ return (cp1 < cp2);
}
/*
* Acquire 4 cnode locks.
- * - locked in cnode parent-child order (if there is a relationship)
- * otherwise lock in cnode address order (lesser address first).
+ * - locked in cnode address order (lesser address first).
* - all or none of the locks are taken
* - only one lock taken per cnode (dup cnodes are skipped)
* - some of the cnode pointers may be null
*/
-__private_extern__
int
hfs_lockfour(struct cnode *cp1, struct cnode *cp2, struct cnode *cp3,
- struct cnode *cp4, enum hfslocktype locktype)
+ struct cnode *cp4, enum hfslocktype locktype, struct cnode **error_cnode)
{
struct cnode * a[3];
struct cnode * b[3];
struct cnode * tmp;
int i, j, k;
int error;
+ if (error_cnode) {
+ *error_cnode = NULL;
+ }
if (hfs_isordered(cp1, cp2)) {
a[0] = cp1; a[1] = cp2;
for (i = 0; i < k; ++i) {
if (list[i])
if ((error = hfs_lock(list[i], locktype))) {
+ /* Only stuff error_cnode if requested */
+ if (error_cnode) {
+ *error_cnode = list[i];
+ }
/* Drop any locks we acquired. */
while (--i >= 0) {
if (list[i])
/*
* Unlock a cnode.
*/
-__private_extern__
void
hfs_unlock(struct cnode *cp)
{
vnode_t rvp = NULLVP;
- vnode_t dvp = NULLVP;
+ vnode_t vp = NULLVP;
+ u_int32_t c_flag;
+ void *lockowner;
- /* System files need to keep track of owner */
- if ((cp->c_fileid < kHFSFirstUserCatalogNodeID) &&
- (cp->c_fileid > kHFSRootFolderID) &&
- (cp->c_datafork != NULL)) {
- /*
- * The extents and bitmap file locks support
- * recursion and are always taken exclusive.
- */
- if (cp->c_fileid == kHFSExtentsFileID ||
- cp->c_fileid == kHFSAllocationFileID) {
- if (--cp->c_syslockcount > 0) {
- return;
- }
+ /*
+ * Only the extents and bitmap file's support lock recursion.
+ */
+ if ((cp->c_fileid == kHFSExtentsFileID) ||
+ (cp->c_fileid == kHFSAllocationFileID)) {
+ if (--cp->c_syslockcount > 0) {
+ return;
}
}
- if (cp->c_flag & C_NEED_DVNODE_PUT)
- dvp = cp->c_vp;
+ c_flag = cp->c_flag;
+ cp->c_flag &= ~(C_NEED_DVNODE_PUT | C_NEED_RVNODE_PUT | C_NEED_DATA_SETSIZE | C_NEED_RSRC_SETSIZE);
- if (cp->c_flag & C_NEED_RVNODE_PUT)
+ if (c_flag & (C_NEED_DVNODE_PUT | C_NEED_DATA_SETSIZE)) {
+ vp = cp->c_vp;
+ }
+ if (c_flag & (C_NEED_RVNODE_PUT | C_NEED_RSRC_SETSIZE)) {
rvp = cp->c_rsrc_vp;
+ }
- cp->c_flag &= ~(C_NEED_DVNODE_PUT | C_NEED_RVNODE_PUT);
-
- cp-> c_lockowner = NULL;
- lck_rw_done(&cp->c_rwlock);
+ lockowner = cp->c_lockowner;
+ if (lockowner == current_thread()) {
+ cp->c_lockowner = NULL;
+ lck_rw_unlock_exclusive(&cp->c_rwlock);
+ } else {
+ lck_rw_unlock_shared(&cp->c_rwlock);
+ }
- if (dvp)
- vnode_put(dvp);
- if (rvp)
- vnode_put(rvp);
+ /* Perform any vnode post processing after cnode lock is dropped. */
+ if (vp) {
+ if (c_flag & C_NEED_DATA_SETSIZE)
+ ubc_setsize(vp, 0);
+ if (c_flag & C_NEED_DVNODE_PUT)
+ vnode_put(vp);
+ }
+ if (rvp) {
+ if (c_flag & C_NEED_RSRC_SETSIZE)
+ ubc_setsize(rvp, 0);
+ if (c_flag & C_NEED_RVNODE_PUT)
+ vnode_put(rvp);
+ }
}
/*
* Unlock a pair of cnodes.
*/
-__private_extern__
void
hfs_unlockpair(struct cnode *cp1, struct cnode *cp2)
{
/*
* Unlock a group of cnodes.
*/
-__private_extern__
void
hfs_unlockfour(struct cnode *cp1, struct cnode *cp2, struct cnode *cp3, struct cnode *cp4)
{
*
* The process doing a truncation must take the lock
* exclusive. The read/write processes can take it
- * non-exclusive.
+ * shared. The locktype argument is the same as supplied to
+ * hfs_lock.
*/
-__private_extern__
void
-hfs_lock_truncate(struct cnode *cp, int exclusive)
+hfs_lock_truncate(struct cnode *cp, enum hfslocktype locktype)
{
- if (cp->c_lockowner == current_thread())
- panic("hfs_lock_truncate: cnode 0x%08x locked!", cp);
+ void * thread = current_thread();
- if (exclusive)
- lck_rw_lock_exclusive(&cp->c_truncatelock);
- else
+ if (cp->c_truncatelockowner == thread) {
+ /*
+ * Only HFS_RECURSE_TRUNCLOCK is allowed to recurse.
+ *
+ * This is needed on the hfs_vnop_pagein path where we need to ensure
+ * the file does not change sizes while we are paging in. However,
+ * we may already hold the lock exclusive due to another
+ * VNOP from earlier in the call stack. So if we already hold
+ * the truncate lock exclusive, allow it to proceed, but ONLY if
+ * it's in the recursive case.
+ */
+ if (locktype != HFS_RECURSE_TRUNCLOCK) {
+ panic("hfs_lock_truncate: cnode %p locked!", cp);
+ }
+ }
+ /* HFS_RECURSE_TRUNCLOCK takes a shared lock if it is not already locked */
+ else if ((locktype == HFS_SHARED_LOCK) || (locktype == HFS_RECURSE_TRUNCLOCK)) {
lck_rw_lock_shared(&cp->c_truncatelock);
+ cp->c_truncatelockowner = HFS_SHARED_OWNER;
+ }
+ else { /* must be an HFS_EXCLUSIVE_LOCK */
+ lck_rw_lock_exclusive(&cp->c_truncatelock);
+ cp->c_truncatelockowner = thread;
+ }
}
-__private_extern__
-void
-hfs_unlock_truncate(struct cnode *cp)
-{
- lck_rw_done(&cp->c_truncatelock);
+
+/*
+ * Attempt to get the truncate lock. If it cannot be acquired, error out.
+ * This function is needed in the degenerate hfs_vnop_pagein during force unmount
+ * case. To prevent deadlocks while a VM copy object is moving pages, HFS vnop pagein will
+ * temporarily need to disable V2 semantics.
+ */
+int hfs_try_trunclock (struct cnode *cp, enum hfslocktype locktype) {
+ void * thread = current_thread();
+ boolean_t didlock = false;
+
+ if (cp->c_truncatelockowner == thread) {
+ /*
+ * Only HFS_RECURSE_TRUNCLOCK is allowed to recurse.
+ *
+ * This is needed on the hfs_vnop_pagein path where we need to ensure
+ * the file does not change sizes while we are paging in. However,
+ * we may already hold the lock exclusive due to another
+ * VNOP from earlier in the call stack. So if we already hold
+ * the truncate lock exclusive, allow it to proceed, but ONLY if
+ * it's in the recursive case.
+ */
+ if (locktype != HFS_RECURSE_TRUNCLOCK) {
+ panic("hfs_lock_truncate: cnode %p locked!", cp);
+ }
+ }
+ /* HFS_RECURSE_TRUNCLOCK takes a shared lock if it is not already locked */
+ else if ((locktype == HFS_SHARED_LOCK) || (locktype == HFS_RECURSE_TRUNCLOCK)) {
+ didlock = lck_rw_try_lock(&cp->c_truncatelock, LCK_RW_TYPE_SHARED);
+ if (didlock) {
+ cp->c_truncatelockowner = HFS_SHARED_OWNER;
+ }
+ }
+ else { /* must be an HFS_EXCLUSIVE_LOCK */
+ didlock = lck_rw_try_lock (&cp->c_truncatelock, LCK_RW_TYPE_EXCLUSIVE);
+ if (didlock) {
+ cp->c_truncatelockowner = thread;
+ }
+ }
+
+ return didlock;
}
+/*
+ * Unlock the truncate lock, which protects against size changes.
+ *
+ * The been_recursed argument is used when we may need to return
+ * from this function without actually unlocking the truncate lock.
+ */
+void
+hfs_unlock_truncate(struct cnode *cp, int been_recursed)
+{
+ void *thread = current_thread();
+ /*
+ * If been_recursed is nonzero AND the current lock owner of the
+ * truncate lock is our current thread, then we must have recursively
+ * taken the lock earlier on. If the lock were unlocked,
+ * HFS_RECURSE_TRUNCLOCK took a shared lock and it would fall through
+ * to the SHARED case below.
+ *
+ * If been_recursed is zero (most of the time) then we check the
+ * lockowner field to infer whether the lock was taken exclusively or
+ * shared in order to know what underlying lock routine to call.
+ */
+ if (been_recursed) {
+ if (cp->c_truncatelockowner == thread) {
+ return;
+ }
+ }
+ /* HFS_LOCK_EXCLUSIVE */
+ if (thread == cp->c_truncatelockowner) {
+ cp->c_truncatelockowner = NULL;
+ lck_rw_unlock_exclusive(&cp->c_truncatelock);
+ }
+ /* HFS_LOCK_SHARED */
+ else {
+ lck_rw_unlock_shared(&cp->c_truncatelock);
+ }
+}
projects / apple / xnu.git / blobdiff