/*
- * Copyright (c) 2002-2008 Apple Inc. All rights reserved.
+ * Copyright (c) 2002-2015 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
#include <sys/ubc.h>
#include <sys/quota.h>
#include <sys/kdebug.h>
+#include <libkern/OSByteOrder.h>
+#include <sys/buf_internal.h>
+#include <sys/namei.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>
+#include <hfs/hfs_kdebug.h>
+#include <hfs/hfs_cprotect.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(hfsmount_t *hfsmp, 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 void hfs_reclaim_cnode(struct cnode *);
+extern int hfs_removefile_callback(struct buf *bp, void *hfsmp);
-static int hfs_isordered(struct cnode *, struct cnode *);
+__inline__ int hfs_checkdeleted (struct cnode *cp) {
+ return ((cp->c_flag & (C_DELETED | C_NOEXISTS)) ? ENOENT : 0);
+}
/*
- * Last reference to an cnode. If necessary, write or delete it.
+ * 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
*/
-__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);
+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;
+ }
- if ((hfsmp->hfs_flags & HFS_READ_ONLY) || vnode_issystem(vp) ||
- (hfsmp->hfs_freezing_proc == p)) {
- return (0);
+ /* lock the cnode */
+ err = hfs_lock (cp, HFS_EXCLUSIVE_LOCK, HFS_LOCK_DEFAULT);
+ if (err) {
+ return err;
+ }
+
+ if (val) {
+ cp->c_flag |= C_BACKINGSTORE;
+ }
+ else {
+ cp->c_flag &= ~C_BACKINGSTORE;
}
- /*
- * Ignore nodes related to stale file handles.
- */
- if (cp->c_mode == 0) {
- vnode_recycle(vp);
- return (0);
+ /* unlock everything */
+ hfs_unlock (cp);
+
+ return err;
+}
+
+/*
+ * 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
+ */
+
+int hfs_is_backingstore (struct vnode *vp, int *val) {
+ struct cnode *cp = NULL;
+ int err = 0;
+
+ if (!vnode_isreg(vp) && !vnode_isdir(vp)) {
+ *val = 0;
+ return 0;
}
- if ((v_type == VREG || v_type == VLNK)) {
- hfs_lock_truncate(cp, TRUE);
- took_trunc_lock = 1;
+ cp = VTOC(vp);
+
+ /* lock the cnode */
+ err = hfs_lock (cp, HFS_SHARED_LOCK, HFS_LOCK_DEFAULT);
+ if (err) {
+ return err;
}
- (void) hfs_lock(cp, HFS_FORCE_LOCK);
+ if (cp->c_flag & C_BACKINGSTORE) {
+ *val = 1;
+ }
+ else {
+ *val = 0;
+ }
- /*
- * We should lock cnode before checking the flags in the
- * condition below and should unlock the cnode before calling
- * ubc_setsize() as cluster code can call other HFS vnops which
- * will try to acquire the same cnode lock and cause deadlock.
- */
- if ((v_type == VREG || v_type == VLNK) &&
- (cp->c_flag & C_DELETED) &&
- (VTOF(vp)->ff_blocks != 0)) {
- hfs_unlock(cp);
- ubc_setsize(vp, 0);
- (void) hfs_lock(cp, HFS_FORCE_LOCK);
+ /* unlock everything */
+ hfs_unlock (cp);
+
+ 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;
+ bool started_tr = false;
+ 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;
}
- if (v_type == VREG && !ISSET(cp->c_flag, C_DELETED) && VTOF(vp)->ff_blocks) {
- hfs_filedone(vp, ap->a_context);
+ /*
+ * 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)) {
+ /*
+ * If we're called from hfs_vnop_inactive, all this means is at the time
+ * the logic for deciding to call this function, there were not any lingering
+ * mmap/fd references for this file. However, there is nothing preventing the system
+ * from creating a new reference in between the time that logic was checked
+ * and we entered hfs_vnop_inactive. As a result, the only time we can guarantee
+ * that there aren't any references is during vnop_reclaim.
+ */
+ hfs_filedone(vp, ctx, 0);
}
+
/*
* Remove any directory hints or cached origins
*/
if (v_type == VDIR) {
hfs_reldirhints(cp, 0);
- }
-
+ }
if (cp->c_flag & C_HARDLINK) {
hfs_relorigins(cp);
}
- 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 (VTOF(vp)->ff_blocks != 0) {
- /*
- * Since we're already inside a transaction,
- * tell hfs_truncate to skip the ubc_setsize.
- */
- error = hfs_truncate(vp, (off_t)0, IO_NDELAY, 1, ap->a_context);
- if (error)
- goto out;
- truncated = 1;
- }
- recycle = 1;
-
+ /*
+ * -- Handle open unlinked files --
+ *
+ * If the vnode is in use, it means a force unmount is in progress
+ * in which case we defer cleaning up until either we come back
+ * through here via hfs_vnop_reclaim, at which point the UBC
+ * information will have been torn down and the vnode might no
+ * longer be in use, or if it's still in use, it will get cleaned
+ * up when next remounted.
+ */
+ if (ISSET(cp->c_flag, C_DELETED) && !vnode_isinuse(vp, 0)) {
/*
- * Check if there's any resource fork blocks that need to
- * be reclaimed. This covers the case where there is a
- * resource fork but its not in core.
+ * 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 ((cp->c_blocks > 0) && (forkcount == 1) && (vp != cp->c_rsrc_vp)) {
- struct vnode *rvp = NULLVP;
+
+ if ((v_type == VREG || v_type == VLNK) &&
+ ((forkcount == 1) || (!VNODE_IS_RSRC(vp)))) {
+
+ /* Truncate away our own fork data. (Case A, B, C above) */
+ if (VTOF(vp)->ff_blocks != 0) {
+ /*
+ * SYMLINKS only:
+ *
+ * Encapsulate the entire change (including truncating the link) in
+ * nested transactions if we are modifying a symlink, because we know that its
+ * file length will be at most 4k, and we can fit both the truncation and
+ * any relevant bitmap changes into a single journal transaction. We also want
+ * the kill_block code to execute in the same transaction so that any dirty symlink
+ * blocks will not be written. Otherwise, rely on
+ * hfs_truncate doing its own transactions to ensure that we don't blow up
+ * the journal.
+ */
+ if (!started_tr && (v_type == VLNK)) {
+ if (hfs_start_transaction(hfsmp) != 0) {
+ error = EINVAL;
+ goto out;
+ }
+ else {
+ started_tr = true;
+ }
+ }
- error = hfs_vgetrsrc(hfsmp, vp, &rvp, FALSE);
- if (error)
- goto out;
- /*
- * Defer the vnode_put and ubc_setsize on rvp until hfs_unlock().
+ /*
+ * At this point, we have decided that this cnode is
+ * suitable for full removal. We are about to deallocate
+ * its blocks and remove its entry from the catalog.
+ * If it was a symlink, then it's possible that the operation
+ * which created it is still in the current transaction group
+ * due to coalescing. Take action here to kill the data blocks
+ * of the symlink out of the journal before moving to
+ * deallocate the blocks. We need to be in the middle of
+ * a transaction before calling buf_iterate like this.
+ *
+ * Note: we have to kill any potential symlink buffers out of
+ * the journal prior to deallocating their blocks. This is so
+ * that we don't race with another thread that may be doing an
+ * an allocation concurrently and pick up these blocks. It could
+ * generate I/O against them which could go out ahead of our journal
+ * transaction.
+ */
+
+ if (hfsmp->jnl && vnode_islnk(vp)) {
+ buf_iterate(vp, hfs_removefile_callback, BUF_SKIP_NONLOCKED, (void *)hfsmp);
+ }
+
+
+ /*
+ * 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, 0, ctx);
+ if (error) {
+ goto out;
+ }
+ truncated = 1;
+
+ /* (SYMLINKS ONLY): Close/End our transaction after truncating the file record */
+ if (started_tr) {
+ hfs_end_transaction(hfsmp);
+ started_tr = false;
+ }
+
+ }
+
+ /*
+ * 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. To avoid bringing a vnode into core for the sole purpose of deleting the
+ * data in the resource fork, we call cat_lookup directly, then hfs_release_storage
+ * to get rid of the resource fork's data. Note that because we are holding the
+ * cnode lock, it is impossible for a competing thread to create the resource fork
+ * vnode from underneath us while we do this.
+ *
+ * This is invoked via case A above only.
*/
- cp->c_flag |= C_NEED_RVNODE_PUT | C_NEED_RSRC_SETSIZE;
- error = hfs_truncate(rvp, (off_t)0, IO_NDELAY, 1, ap->a_context);
- if (error)
- goto out;
- vnode_recycle(rvp); /* all done with this vnode */
- }
- }
+ if ((cp->c_blocks > 0) && (forkcount == 1) && (vp != cp->c_rsrc_vp)) {
+ struct cat_lookup_buffer *lookup_rsrc = NULL;
+ struct cat_desc *desc_ptr = NULL;
+ lockflags = 0;
+
+ MALLOC(lookup_rsrc, struct cat_lookup_buffer*, sizeof (struct cat_lookup_buffer), M_TEMP, M_WAITOK);
+ if (lookup_rsrc == NULL) {
+ printf("hfs_cnode_teardown: ENOMEM from MALLOC\n");
+ error = ENOMEM;
+ goto out;
+ }
+ else {
+ bzero (lookup_rsrc, sizeof (struct cat_lookup_buffer));
+ }
- // If needed, get rid of any xattrs that this file may have.
- // 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_attr.ca_recflags & kHFSHasAttributesMask) != 0 && (cp->c_flag & C_DELETED)) {
- hfs_removeallattr(hfsmp, cp->c_fileid);
- }
+ if (cp->c_desc.cd_namelen == 0) {
+ /* Initialize the rsrc descriptor for lookup if necessary*/
+ MAKE_DELETED_NAME (lookup_rsrc->lookup_name, HFS_TEMPLOOKUP_NAMELEN, cp->c_fileid);
+
+ lookup_rsrc->lookup_desc.cd_nameptr = (const uint8_t*) lookup_rsrc->lookup_name;
+ lookup_rsrc->lookup_desc.cd_namelen = strlen (lookup_rsrc->lookup_name);
+ lookup_rsrc->lookup_desc.cd_parentcnid = hfsmp->hfs_private_desc[FILE_HARDLINKS].cd_cnid;
+ lookup_rsrc->lookup_desc.cd_cnid = cp->c_cnid;
+
+ desc_ptr = &lookup_rsrc->lookup_desc;
+ }
+ else {
+ desc_ptr = &cp->c_desc;
+ }
- /*
- * Check for a postponed deletion.
- * (only delete cnode when the last fork goes inactive)
- */
- 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);
- // 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(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, HFS_SHARED_LOCK);
- lockflags = hfs_systemfile_lock(hfsmp, SFL_CATALOG | SFL_ATTRIBUTE, HFS_EXCLUSIVE_LOCK);
+ error = cat_lookup (hfsmp, desc_ptr, 1, 0, (struct cat_desc *) NULL,
+ (struct cat_attr*) NULL, &lookup_rsrc->lookup_fork.ff_data, NULL);
- 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);
- }
+ hfs_systemfile_unlock (hfsmp, lockflags);
+
+ if (error) {
+ FREE (lookup_rsrc, M_TEMP);
+ goto out;
+ }
- //
- // 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);
-
- 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]);
+ /*
+ * Make the filefork in our temporary struct look like a real
+ * filefork. Fill in the cp, sysfileinfo and rangelist fields..
+ */
+ rl_init (&lookup_rsrc->lookup_fork.ff_invalidranges);
+ lookup_rsrc->lookup_fork.ff_cp = cp;
+
+ /*
+ * If there were no errors, then we have the catalog's fork information
+ * for the resource fork in question. Go ahead and delete the data in it now.
+ */
+
+ error = hfs_release_storage (hfsmp, NULL, &lookup_rsrc->lookup_fork, cp->c_fileid);
+ FREE(lookup_rsrc, M_TEMP);
+
+ if (error) {
+ goto out;
+ }
+
+ /*
+ * This fileid's resource fork extents have now been fully deleted on-disk
+ * and this CNID is no longer valid. At this point, we should be able to
+ * zero out cp->c_blocks to indicate there is no data left in this file.
+ */
+ cp->c_blocks = 0;
}
- (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 we represent the last fork (or none in the case of a dir),
+ * and the cnode has become open-unlinked...
+ *
+ * We check c_blocks here because it is possible in the force
+ * unmount case for the data fork to be in use but the resource
+ * fork to not be in use in which case we will truncate the
+ * resource fork, but not the data fork. It will get cleaned
+ * up upon next mount.
+ */
+ if (forkcount <= 1 && !cp->c_blocks) {
+ /*
+ * If 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 (ISSET(cp->c_attr.ca_recflags, kHFSHasAttributesMask))
+ ea_error = hfs_removeallattr(hfsmp, cp->c_fileid, &started_tr);
-#if QUOTA
- if (hfsmp->hfs_flags & HFS_QUOTAS)
- (void)hfs_chkiq(cp, -1, NOCRED, 0);
-#endif /* QUOTA */
+ /*
+ * Remove the cnode's catalog entry and release all blocks it
+ * may have been using.
+ */
- cp->c_mode = 0;
- cp->c_flag &= ~C_DELETED;
- cp->c_touch_chgtime = TRUE;
- cp->c_touch_modtime = TRUE;
+ /*
+ * 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) {
+ if (hfs_start_transaction(hfsmp) != 0) {
+ error = EINVAL;
+ goto out;
+ }
+ started_tr = true;
+ }
+
+ /*
+ * 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);
+ }
+
+ //
+ // 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);
+
+ 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
+ if (hfsmp->hfs_flags & HFS_QUOTAS)
+ (void)hfs_chkiq(cp, -1, NOCRED, 0);
+ #endif /* QUOTA */
+
+ /* 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);
+ }
+ } // if <open unlinked>
- if (error == 0)
- hfs_volupdate(hfsmp, (v_type == VDIR) ? VOL_RMDIR : VOL_RMFILE, 0);
- }
+ hfs_update(vp, reclaim ? HFS_UPDATE_FORCE : 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.
+ * Since we are about to finish what might be an inactive call, propagate
+ * any remaining modified or touch bits from the cnode to the vnode. This
+ * serves as a hint to vnode recycling that we shouldn't recycle this vnode
+ * synchronously.
+ *
+ * For now, if the node *only* has a dirty atime, we don't mark
+ * the vnode as dirty. VFS's asynchronous recycling can actually
+ * lead to worse performance than having it synchronous. When VFS
+ * is fixed to be more performant, we can be more honest about
+ * marking vnodes as dirty when it's only the atime that's dirty.
*/
- if ((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);
+ if (hfs_is_dirty(cp) == HFS_DIRTY || ISSET(cp->c_flag, C_DELETED)) {
+ vnode_setdirty(vp);
+ } else {
+ vnode_cleardirty(vp);
}
+
out:
- if (cat_reserve)
- cat_postflight(hfsmp, &cookie, p);
+ if (cat_reserve)
+ cat_postflight(hfsmp, &cookie, p);
+
+ if (started_tr) {
+ hfs_end_transaction(hfsmp);
+ started_tr = false;
+ }
- // XXXdbg - have to do this because a goto could have come here
- if (started_tr) {
- hfs_end_transaction(hfsmp);
- started_tr = 0;
- }
+ return error;
+}
- hfs_unlock(cp);
- if (took_trunc_lock)
- hfs_unlock_truncate(cp, TRUE);
+/*
+ * 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);
+
+ 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, HFS_LOCK_DEFAULT);
+ took_trunc_lock = 1;
+ }
+
+ (void) hfs_lock(cp, HFS_EXCLUSIVE_LOCK, HFS_LOCK_ALLOW_NOEXISTS);
+
+ /*
+ * 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, HFS_LOCK_DEFAULT);
+ }
- return (error);
+ hfs_unlock(cp);
+
+inactive_done:
+
+ return error;
}
+
/*
* File clean-up (zero fill and shrink peof).
*/
-static int
-hfs_filedone(struct vnode *vp, vfs_context_t context)
+
+int
+hfs_filedone(struct vnode *vp, vfs_context_t context,
+ hfs_file_done_opts_t opts)
{
struct cnode *cp;
struct filefork *fp;
struct hfsmount *hfsmp;
off_t leof;
- u_long blks, blocksize;
+ u_int32_t blks, blocksize;
cp = VTOC(vp);
fp = VTOF(vp);
if ((hfsmp->hfs_flags & HFS_READ_ONLY) || (fp->ff_blocks == 0))
return (0);
- hfs_unlock(cp);
- (void) cluster_push(vp, IO_CLOSE);
- 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);
- off_t start = invalid_range->rl_start;
- off_t end = invalid_range->rl_end;
-
- /* The range about to be written must be validated
- * first, so that VNOP_BLOCKMAP() will return the
- * appropriate mapping for the cluster code:
- */
- rl_remove(start, end, &fp->ff_invalidranges);
+ hfs_flush_invalid_ranges(vp);
- hfs_unlock(cp);
- (void) cluster_write(vp, (struct uio *) 0,
- leof, end + 1, start, (off_t)0,
- IO_HEADZEROFILL | IO_NOZERODIRTY | IO_NOCACHE);
- hfs_lock(cp, HFS_FORCE_LOCK);
- cp->c_flag |= C_MODIFIED;
- }
- cp->c_flag &= ~C_ZFWANTSYNC;
- cp->c_zftimeout = 0;
blocksize = VTOVCB(vp)->blockSize;
blks = leof / blocksize;
if (((off_t)blks * (off_t)blocksize) != leof)
/*
* 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);
- hfs_unlock(cp);
- (void) cluster_push(vp, IO_CLOSE);
- hfs_lock(cp, HFS_FORCE_LOCK);
-
- /*
- * If the hfs_truncate didn't happen to flush the vnode's
- * information out to disk, force it to be updated now that
- * all invalid ranges have been zero-filled and validated:
- */
- if (cp->c_flag & C_MODIFIED) {
+ if (blks < fp->ff_blocks) {
+ (void) hfs_truncate(vp, leof, IO_NDELAY, HFS_TRUNCATE_SKIPTIMES, context);
+ }
+
+ if (!ISSET(opts, HFS_FILE_DONE_NO_SYNC)) {
+ hfs_unlock(cp);
+ cluster_push(vp, IO_CLOSE);
+ hfs_lock(cp, HFS_EXCLUSIVE_LOCK, HFS_LOCK_ALLOW_NOEXISTS);
+
+ /*
+ * If the hfs_truncate didn't happen to flush the vnode's
+ * information out to disk, force it to be updated now that
+ * all invalid ranges have been zero-filled and validated:
+ */
hfs_update(vp, 0);
}
+
return (0);
}
/*
* 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);
-
- /*
- * Check if a deleted resource fork vnode missed a
- * VNOP_INACTIVE call and requires truncation.
+
+ /*
+ * 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.
*/
- if (VNODE_IS_RSRC(vp) &&
- (cp->c_flag & C_DELETED) &&
- (VTOF(vp)->ff_blocks != 0)) {
- hfs_unlock(cp);
- ubc_setsize(vp, 0);
-
- hfs_lock_truncate(cp, TRUE);
- (void) hfs_lock(VTOC(vp), HFS_FORCE_LOCK);
+ (void) hfs_lock(cp, HFS_EXCLUSIVE_LOCK, HFS_LOCK_ALLOW_NOEXISTS);
- (void) hfs_truncate(vp, (off_t)0, IO_NDELAY, 1, ap->a_context);
-
- hfs_unlock_truncate(cp, TRUE);
- }
- /*
- * 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.
+ /*
+ * 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 ((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);
+ if (!ISSET(cp->c_flag, C_NOEXISTS)) {
+ err = hfs_cnode_teardown(vp, ctx, 1);
}
/*
- * Keep track of an inactive hot file.
+ * Keep track of an inactive hot file. Don't bother on ssd's since
+ * the tracking is done differently (it's done at read() time)
*/
if (!vnode_isdir(vp) &&
!vnode_issystem(vp) &&
- !(cp->c_flag & (C_DELETED | C_NOEXISTS)) ) {
+ !(cp->c_flag & (C_DELETED | C_NOEXISTS)) &&
+ !(hfsmp->hfs_flags & HFS_CS_HOTFILE_PIN)) {
(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
hfs_reldirhints(cp, 0);
}
- if (cp->c_flag & C_HARDLINK) {
+ if(cp->c_flag & C_HARDLINK) {
hfs_relorigins(cp);
}
}
/* Dump cached symlink data */
if (vnode_islnk(vp) && (fp->ff_symlinkptr != NULL)) {
FREE(fp->ff_symlinkptr, M_TEMP);
- }
+ }
+ rl_remove_all(&fp->ff_invalidranges);
FREE_ZONE(fp, sizeof(struct filefork), M_HFSFORK);
}
* If there was only one active fork then we can release the cnode.
*/
if (reclaim_cnode) {
- hfs_chashwakeup(cp, H_ALLOC | H_TRANSIT);
- hfs_reclaim_cnode(cp);
- } else /* cnode in use */ {
+ hfs_chashwakeup(hfsmp, cp, H_ALLOC | H_TRANSIT);
+ hfs_unlock(cp);
+ hfs_reclaim_cnode(hfsmp, cp);
+ }
+ 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_fifoop_p) (void *);
#endif
+#if CONFIG_HFS_STD
+extern int (**hfs_std_vnodeop_p) (void *);
+#endif
+
/*
* hfs_getnewvnode - get new default vnode
*
- * The vnode is returned with an iocount and the cnode locked
+ * The vnode is returned with an iocount and the cnode locked.
+ * The cnode of the parent vnode 'dvp' may or may not be locked, depending on
+ * the circumstances. The cnode in question (if acquiring the resource fork),
+ * may also already be locked at the time we enter this function.
+ *
+ * Note that there are both input and output flag arguments to this function.
+ * If one of the input flags (specifically, GNV_USE_VP), is set, then
+ * hfs_getnewvnode will use the parameter *vpp, which is traditionally only
+ * an output parameter, as both an input and output parameter. It will use
+ * the vnode provided in the output, and pass it to vnode_create with the
+ * proper flavor so that a new vnode is _NOT_ created on our behalf when
+ * we dispatch to VFS. This may be important in various HFS vnode creation
+ * routines, such a create or get-resource-fork, because we risk deadlock if
+ * jetsam is involved.
+ *
+ * Deadlock potential exists if jetsam is synchronously invoked while we are waiting
+ * for a vnode to be recycled in order to give it the identity we want. If jetsam
+ * happens to target a process for termination that is blocked in-kernel, waiting to
+ * acquire the cnode lock on our parent 'dvp', while our current thread has it locked,
+ * neither side will make forward progress and the watchdog timer will eventually fire.
+ * To prevent this, a caller of hfs_getnewvnode may choose to proactively force
+ * any necessary vnode reclamation/recycling while it is not holding any locks and
+ * thus not prone to deadlock. If this is the case, GNV_USE_VP will be set and
+ * the parameter will be used as described above.
+ *
+ * !!! <NOTE> !!!!
+ * In circumstances when GNV_USE_VP is set, this function _MUST_ clean up and either consume
+ * or dispose of the provided vnode. We funnel all errors to a single return value so that
+ * if provided_vp is still non-NULL, then we will dispose of the vnode. This will occur in
+ * all error cases of this function -- anywhere we zero/NULL out the *vpp parameter. It may
+ * also occur if the current thread raced with another to create the same vnode, and we
+ * find the entry already present in the cnode hash.
+ * !!! </NOTE> !!!
*/
-__private_extern__
int
hfs_getnewvnode(
struct hfsmount *hfsmp,
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 retval;
+ int hfs_standard = 0;
+ int retval = 0;
int issystemfile;
int wantrsrc;
+ int hflags = 0;
+ int need_update_identity = 0;
struct vnode_fsparam vfsp;
enum vtype vtype;
+
+ struct vnode *provided_vp = NULL;
+
+
#if QUOTA
int i;
#endif /* QUOTA */
+
+ hfs_standard = (hfsmp->hfs_flags & HFS_STANDARD);
+
+ if (flags & GNV_USE_VP) {
+ /* Store the provided VP for later use */
+ provided_vp = *vpp;
+ }
+
+ /* Zero out the vpp regardless of provided input */
+ *vpp = NULL;
+
+ /* Zero out the out_flags */
+ *out_flags = 0;
if (attrp->ca_fileid == 0) {
- *vpp = NULL;
- return (ENOENT);
+ retval = ENOENT;
+ goto gnv_exit;
}
#if !FIFO
if (IFTOVT(attrp->ca_mode) == VFIFO) {
- *vpp = NULL;
- return (ENOTSUP);
+ retval = ENOTSUP;
+ goto gnv_exit;
}
#endif /* !FIFO */
vtype = IFTOVT(attrp->ca_mode);
issystemfile = (descp->cd_flags & CD_ISMETA) && (vtype == VREG);
wantrsrc = flags & GNV_WANTRSRC;
+ /* Sanity check the vtype and mode */
+ if (vtype == VBAD) {
+ /* Mark the FS as corrupt and bail out */
+ hfs_mark_inconsistent(hfsmp, HFS_INCONSISTENCY_DETECTED);
+ retval = EINVAL;
+ goto gnv_exit;
+ }
+
#ifdef HFS_CHECK_LOCK_ORDER
/*
- * The only case were its permissible to hold the parent cnode
+ * The only case where it's 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).
*/
/*
* Get a cnode (new or existing)
*/
- cp = hfs_chash_getcnode(hfsmp->hfs_raw_dev, attrp->ca_fileid, vpp, wantrsrc, (flags & GNV_SKIPLOCK));
+ cp = hfs_chash_getcnode(hfsmp, attrp->ca_fileid, vpp, wantrsrc,
+ (flags & GNV_SKIPLOCK), out_flags, &hflags);
/*
* If the id is no longer valid for lookups we'll get back a NULL cp.
*/
if (cp == NULL) {
- return (ENOENT);
+ retval = ENOENT;
+ goto gnv_exit;
}
+ /*
+ * We may have been provided a vnode via
+ * GNV_USE_VP. In this case, we have raced with
+ * a 2nd thread to create the target vnode. The provided
+ * vnode that was passed in will be dealt with at the
+ * end of the function, as we don't zero out the field
+ * until we're ready to pass responsibility to VFS.
+ */
- /* 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 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 the bytes of the filename in the descp do not match the bytes in the
+ // cnp (and we're not looking up the resource fork), then we want to update
+ // the vnode identity to contain the bytes that HFS stores so that when an
+ // fsevent gets generated, it has the correct filename. otherwise daemons
+ // that match filenames produced by fsevents with filenames they have stored
+ // elsewhere (e.g. bladerunner, backupd, mds), the filenames will not match.
+ // See: <rdar://problem/8044697> FSEvents doesn't always decompose diacritical unicode chars in the paths of the changed directories
+ // for more details.
+ //
+#ifdef CN_WANTSRSRCFORK
+ if (*vpp && cnp && cnp->cn_nameptr && !(cnp->cn_flags & CN_WANTSRSRCFORK) && descp && descp->cd_nameptr && strncmp((const char *)cnp->cn_nameptr, (const char *)descp->cd_nameptr, descp->cd_namelen) != 0) {
+#else
+ if (*vpp && cnp && cnp->cn_nameptr && descp && descp->cd_nameptr && strncmp((const char *)cnp->cn_nameptr, (const char *)descp->cd_nameptr, descp->cd_namelen) != 0) {
+#endif
+ vnode_update_identity (*vpp, dvp, (const char *)descp->cd_nameptr, descp->cd_namelen, 0, VNODE_UPDATE_NAME);
+ }
+ 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;
+ retval = ERECYCLE;
+ goto gnv_exit;
+ }
+ else {
+ /*
+ * Otherwise, CNID != fileid. Go ahead and copy in the new descriptor.
+ *
+ * Replacing the descriptor here is fine because we looked up the item without
+ * a vnode in hand before. If a vnode existed, its identity must be attached to this
+ * item. We are not susceptible to the lookup fastpath issue at this point.
+ */
+ replace_desc(cp, descp);
+
+ /*
+ * This item was a hardlink, and its name needed to be updated. By replacing the
+ * descriptor above, we've now updated the cnode's internal representation of
+ * its link ID/CNID, parent ID, and its name. However, VFS must now be alerted
+ * to the fact that this vnode now has a new parent, since we cannot guarantee
+ * that the new link lived in the same directory as the alternative name for
+ * this item.
+ */
+ if ((*vpp != NULL) && (cnp || cp->c_desc.cd_nameptr)) {
+ /* we could be requesting the rsrc of a hardlink file... */
+#ifdef CN_WANTSRSRCFORK
+ if (cp->c_desc.cd_nameptr && (cnp == NULL || !(cnp->cn_flags & CN_WANTSRSRCFORK))) {
+#else
+ if (cp->c_desc.cd_nameptr) {
+#endif
+ //
+ // Update the identity with what we have stored on disk as
+ // the name of this file. This is related to:
+ // <rdar://problem/8044697> FSEvents doesn't always decompose diacritical unicode chars in the paths of the changed directories
+ //
+ vnode_update_identity (*vpp, dvp, (const char *)cp->c_desc.cd_nameptr, cp->c_desc.cd_namelen, 0,
+ (VNODE_UPDATE_PARENT | VNODE_UPDATE_NAME));
+ } else if (cnp) {
+ vnode_update_identity (*vpp, dvp, cnp->cn_nameptr, cnp->cn_namelen, cnp->cn_hash,
+ (VNODE_UPDATE_PARENT | VNODE_UPDATE_NAME));
+ }
+ }
+ }
+ }
+ }
+
+ /*
+ * At this point, we have performed hardlink and open-unlinked checks
+ * above. We have now validated the state of the vnode that was given back
+ * to us from the cnode hash code and find it safe to return.
+ */
+ if (*vpp != NULL) {
+ retval = 0;
+ goto gnv_exit;
}
- /* Check if we found a matching vnode */
- 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 (!(flags & GNV_CREATE) &&
- !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);
+ if ((flags & GNV_SKIPLOCK) == 0) {
+ hfs_unlock(cp);
+ }
+ hfs_reclaim_cnode(hfsmp, 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;
+ retval = ENOENT;
+ goto gnv_exit;
+ }
+
+ /*
+ * 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;
+ retval = ERECYCLE;
+ goto gnv_exit;
+ }
+ }
}
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 ((vtype == VREG || vtype == VDIR) &&
- ((descp->cd_cnid != attrp->ca_fileid) ||
- (attrp->ca_recflags & kHFSHasLinkChainMask))) {
+ if ((vtype == VREG || vtype == VDIR
+ || vtype == VSOCK || vtype == VFIFO)
+ && (descp->cd_cnid != attrp->ca_fileid
+ || ISSET(attrp->ca_recflags, kHFSHasLinkChainMask))) {
cp->c_flag |= C_HARDLINK;
}
/*
cp->c_dquot[i] = NODQUOT;
}
#endif /* QUOTA */
+ /* Mark the output flag that we're vending a new cnode */
+ *out_flags |= GNV_NEW_CNODE;
}
if (vtype == VDIR) {
vfsp.vnfs_dvp = dvp;
vfsp.vnfs_cnp = cnp;
}
+
vfsp.vnfs_fsnode = cp;
+
+ /*
+ * Special Case HFS Standard VNOPs from HFS+, since
+ * HFS standard is readonly/deprecated as of 10.6
+ */
+
#if FIFO
- if (vtype == VFIFO )
+ if (vtype == VFIFO )
vfsp.vnfs_vops = hfs_fifoop_p;
else
#endif
if (vtype == VBLK || vtype == VCHR)
vfsp.vnfs_vops = hfs_specop_p;
- else
+#if CONFIG_HFS_STD
+ else if (hfs_standard)
+ vfsp.vnfs_vops = hfs_std_vnodeop_p;
+#endif
+ else
vfsp.vnfs_vops = hfs_vnodeop_p;
-
+
if (vtype == VBLK || vtype == VCHR)
vfsp.vnfs_rdev = attrp->ca_rdev;
else
vfsp.vnfs_filesize = 0;
vfsp.vnfs_flags = VNFS_ADDFSREF;
- if (dvp == NULLVP || cnp == NULL || !(cnp->cn_flags & MAKEENTRY))
+#ifdef CN_WANTSRSRCFORK
+ if (cnp && cnp->cn_nameptr && !(cnp->cn_flags & CN_WANTSRSRCFORK) && cp->c_desc.cd_nameptr && strncmp((const char *)cnp->cn_nameptr, (const char *)cp->c_desc.cd_nameptr, cp->c_desc.cd_namelen) != 0) {
+#else
+ if (cnp && cnp->cn_nameptr && cp->c_desc.cd_nameptr && strncmp((const char *)cnp->cn_nameptr, (const char *)cp->c_desc.cd_nameptr, cp->c_desc.cd_namelen) != 0) {
+#endif
+ //
+ // We don't want VFS to add an entry for this vnode because the name in the
+ // cnp does not match the bytes stored on disk for this file. Instead we'll
+ // update the identity later after the vnode is created and we'll do so with
+ // the correct bytes for this filename. For more details, see:
+ // <rdar://problem/8044697> FSEvents doesn't always decompose diacritical unicode chars in the paths of the changed directories
+ //
+ vfsp.vnfs_flags |= VNFS_NOCACHE;
+ need_update_identity = 1;
+ } else if (dvp == NULLVP || cnp == NULL || !(cnp->cn_flags & MAKEENTRY) || (flags & GNV_NOCACHE)) {
vfsp.vnfs_flags |= VNFS_NOCACHE;
+ }
/* Tag system files */
vfsp.vnfs_marksystem = issystemfile;
vfsp.vnfs_markroot = 1;
else
vfsp.vnfs_markroot = 0;
+
+ /*
+ * If provided_vp was non-NULL, then it is an already-allocated (but not
+ * initialized) vnode. We simply need to initialize it to this identity.
+ * If it was NULL, then assume that we need to call vnode_create with the
+ * normal arguments/types.
+ */
+ if (provided_vp) {
+ vp = provided_vp;
+ /*
+ * After we assign the value of provided_vp into 'vp' (so that it can be
+ * mutated safely by vnode_initialize), we can NULL it out. At this point, the disposal
+ * and handling of the provided vnode will be the responsibility of VFS, which will
+ * clean it up and vnode_put it properly if vnode_initialize fails.
+ */
+ provided_vp = NULL;
+
+ retval = vnode_initialize (VNCREATE_FLAVOR, VCREATESIZE, &vfsp, &vp);
+ /* See error handling below for resolving provided_vp */
+ }
+ else {
+ /* Do a standard vnode_create */
+ retval = vnode_create (VNCREATE_FLAVOR, VCREATESIZE, &vfsp, &vp);
+ }
- if ((retval = vnode_create(VNCREATE_FLAVOR, VCREATESIZE, &vfsp, cvpp))) {
- if (fp) {
+ /*
+ * We used a local variable to hold the result of vnode_create/vnode_initialize so that
+ * on error cases in vnode_create we won't accidentally harm the cnode's fields
+ */
+
+ if (retval) {
+ /* Clean up if we encountered an error */
+ if (fp) {
if (fp == cp->c_datafork)
- cp->c_datafork = NULL;
+ cp->c_datafork = NULL;
else
- cp->c_rsrcfork = NULL;
+ cp->c_rsrcfork = NULL;
- FREE_ZONE(fp, sizeof(struct filefork), M_HFSFORK);
+ FREE_ZONE(fp, sizeof(struct filefork), M_HFSFORK);
}
/*
* If this is a newly created cnode or a vnode reclaim
* occurred during the attachment, then cleanup the cnode.
*/
if ((cp->c_vp == NULL) && (cp->c_rsrc_vp == NULL)) {
- hfs_chash_abort(cp);
- hfs_reclaim_cnode(cp);
+ hfs_chash_abort(hfsmp, cp);
+ hfs_reclaim_cnode(hfsmp, cp);
}
else {
- hfs_chashwakeup(cp, H_ALLOC | H_ATTACH);
+ hfs_chashwakeup(hfsmp, cp, H_ALLOC | H_ATTACH);
if ((flags & GNV_SKIPLOCK) == 0){
hfs_unlock(cp);
}
}
*vpp = NULL;
- return (retval);
+ goto gnv_exit;
}
- vp = *cvpp;
+
+ /* If no error, then assign the value into the cnode's fields */
+ *cvpp = vp;
+
vnode_settag(vp, VT_HFS);
if (cp->c_flag & C_HARDLINK) {
vnode_setmultipath(vp);
}
+
+ if (cp->c_attr.ca_recflags & kHFSFastDevCandidateMask) {
+ vnode_setfastdevicecandidate(vp);
+ }
+
+ if (cp->c_attr.ca_recflags & kHFSAutoCandidateMask) {
+ vnode_setautocandidate(vp);
+ }
+
+
+
+
+ if (vp && need_update_identity) {
+ //
+ // As above, update the name of the vnode if the bytes stored in hfs do not match
+ // the bytes in the cnp. See this radar:
+ // <rdar://problem/8044697> FSEvents doesn't always decompose diacritical unicode chars in the paths of the changed directories
+ // for more details.
+ //
+ vnode_update_identity (vp, dvp, (const char *)cp->c_desc.cd_nameptr, cp->c_desc.cd_namelen, 0, VNODE_UPDATE_NAME);
+ }
+
/*
* 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(HFSDBG_GETNEWVNODE, VM_KERNEL_ADDRPERM(cp->c_vp), VM_KERNEL_ADDRPERM(cp->c_rsrc_vp), 0, 0, 0);
+
/* Force VL_NEEDINACTIVE on this vnode */
- vnode_ref(vp);
- vnode_rele(vp);
+ err = vnode_ref(vp);
+ if (err == 0) {
+ vnode_rele(vp);
+ }
}
- hfs_chashwakeup(cp, H_ALLOC | H_ATTACH);
+ hfs_chashwakeup(hfsmp, cp, H_ALLOC | H_ATTACH);
/*
* Stop tracking an active hot file.
*/
- if (!(flags & GNV_CREATE) && (vtype != VDIR) && !issystemfile) {
+ if (!(flags & GNV_CREATE) && (vtype != VDIR) && !issystemfile && !(hfsmp->hfs_flags & HFS_CS_HOTFILE_PIN)) {
(void) hfs_removehotfile(vp);
}
+
+#if CONFIG_PROTECT
+ /* Initialize the cp data structures. The key should be in place now. */
+ if (!issystemfile && (*out_flags & GNV_NEW_CNODE)) {
+ cp_entry_init(cp, mp);
+ }
+#endif
*vpp = vp;
- return (0);
+ retval = 0;
+
+gnv_exit:
+ if (provided_vp) {
+ /* Release our empty vnode if it was not used */
+ vnode_put (provided_vp);
+ }
+ return retval;
}
static void
-hfs_reclaim_cnode(struct cnode *cp)
+hfs_reclaim_cnode(hfsmount_t *hfsmp, struct cnode *cp)
{
#if QUOTA
int i;
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 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(hfsmp, cp->c_cpentry);
+ cp->c_cpentry = NULL;
+#else
+ (void)hfsmp; // Prevent compiler warning
+#endif
+
bzero(cp, sizeof(struct cnode));
FREE_ZONE(cp, sizeof(struct cnode), M_HFSNODE);
}
-__private_extern__
+/*
+ * 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)
+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 = (const u_int8_t *)cnp->cn_nameptr;
cndesc.cd_namelen = cnp->cn_namelen;
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, 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, 0, NULL, NULL, NULL) == 0) {
+ if (cat_idlookup(hfsmp, cnid, 0, 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;
+}
+
+static u_int32_t
+hfs_get_dateadded_internal(const uint8_t *finderinfo, mode_t mode)
+{
+ const uint8_t *finfo = NULL;
+ u_int32_t dateadded = 0;
+
+
+
+ /* overlay the FinderInfo to the correct pointer, and advance */
+ finfo = finderinfo + 16;
+
+ /*
+ * FinderInfo is written out in big endian... make sure to convert it to host
+ * native before we use it.
+ */
+ if (S_ISREG(mode)) {
+ const struct FndrExtendedFileInfo *extinfo = (const struct FndrExtendedFileInfo *)finfo;
+ dateadded = OSSwapBigToHostInt32 (extinfo->date_added);
+ }
+ else if (S_ISDIR(mode)) {
+ const struct FndrExtendedDirInfo *extinfo = (const struct FndrExtendedDirInfo *)finfo;
+ dateadded = OSSwapBigToHostInt32 (extinfo->date_added);
+ }
+
+ return dateadded;
+}
+
+u_int32_t
+hfs_get_dateadded(struct cnode *cp)
+{
+ if ((cp->c_attr.ca_recflags & kHFSHasDateAddedMask) == 0) {
+ /* Date added was never set. Return 0. */
+ return (0);
+ }
+
+ return (hfs_get_dateadded_internal((u_int8_t*)cp->c_finderinfo,
+ cp->c_attr.ca_mode));
+}
+
+u_int32_t
+hfs_get_dateadded_from_blob(const uint8_t *finderinfo, mode_t mode)
+{
+ return (hfs_get_dateadded_internal(finderinfo, mode));
+}
+
+/*
+ * Per HI and Finder requirements, HFS maintains a "write/generation
+ * count" for each file that is incremented on any write & pageout.
+ * It should start at 1 to reserve "0" as a special value. If it
+ * should ever wrap around, it will skip using 0.
+ *
+ * Note that finderinfo is manipulated in hfs_vnop_setxattr and care
+ * is and should be taken to ignore user attempts to set the part of
+ * the finderinfo that records the generation counter.
+ *
+ * Any change to the generation counter *must* not be visible before
+ * the change that caused it (for obvious reasons), and given the
+ * limitations of our current architecture, the change to the
+ * generation counter may occur some time afterwards (particularly in
+ * the case where a file is mapped writable---more on that below).
+ *
+ * We make no guarantees about the consistency of a file. In other
+ * words, a reader that is operating concurrently with a writer might
+ * see some, but not all of writer's changes, and the generation
+ * counter will *not* necessarily tell you this has happened. To
+ * enforce consistency, clients must make their own arrangements
+ * e.g. use file locking.
+ *
+ * We treat files that are mapped writable as a special case: when
+ * that happens, clients requesting the generation count will be told
+ * it has a generation count of zero and they use that knowledge as a
+ * hint that the file is changing and it therefore might be prudent to
+ * wait until it is no longer mapped writable. Clients should *not*
+ * rely on this behaviour however; we might decide that it's better
+ * for us to publish the fact that a file is mapped writable via
+ * alternate means and return the generation counter when it is mapped
+ * writable as it still has some, albeit limited, use. We reserve the
+ * right to make this change.
+ *
+ * Lastly, it's important to realise that because data and metadata
+ * take different paths through the system, it's possible upon crash
+ * or sudden power loss and after a restart, that a change may be
+ * visible to the rest of the system without a corresponding change to
+ * the generation counter. The reverse may also be true, but for all
+ * practical applications this shouldn't be an issue.
+ */
+void hfs_write_gencount (struct cat_attr *attrp, uint32_t gencount) {
+ 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.
+ *
+ * Generation count is only supported for files.
+ */
+ if (S_ISREG(attrp->ca_mode)) {
+ struct FndrExtendedFileInfo *extinfo = (struct FndrExtendedFileInfo *)finfo;
+ extinfo->write_gen_counter = OSSwapHostToBigInt32(gencount);
+ }
+
+ /* If it were neither directory/file, then we'd bail out */
+ return;
+}
+
+/*
+ * Increase the gen count by 1; if it wraps around to 0, increment by
+ * two. The cnode *must* be locked exclusively by the caller.
+ *
+ * You may think holding the lock is unnecessary because we only need
+ * to change the counter, but consider this sequence of events: thread
+ * A calls hfs_incr_gencount and the generation counter is 2 upon
+ * entry. A context switch occurs and thread B increments the counter
+ * to 3, thread C now gets the generation counter (for whatever
+ * purpose), and then another thread makes another change and the
+ * generation counter is incremented again---it's now 4. Now thread A
+ * continues and it sets the generation counter back to 3. So you can
+ * see, thread C would miss the change that caused the generation
+ * counter to increment to 4 and for this reason the cnode *must*
+ * always be locked exclusively.
+ */
+uint32_t hfs_incr_gencount (struct cnode *cp) {
+ u_int8_t *finfo = NULL;
+ u_int32_t gcount = 0;
+
+ /* 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.
+ *
+ * NOTE: the write_gen_counter is stored in the same location in both the
+ * FndrExtendedFileInfo and FndrExtendedDirInfo structs (it's the
+ * last 32-bit word) so it is safe to have one code path here.
+ */
+ if (S_ISDIR(cp->c_attr.ca_mode) || S_ISREG(cp->c_attr.ca_mode)) {
+ struct FndrExtendedFileInfo *extinfo = (struct FndrExtendedFileInfo *)finfo;
+ gcount = OSSwapBigToHostInt32 (extinfo->write_gen_counter);
+
+ /* Was it zero to begin with (file originated in 10.8 or earlier?) */
+ if (gcount == 0) {
+ gcount++;
+ }
+
+ /* now bump it */
+ gcount++;
+
+ /* Did it wrap around ? */
+ if (gcount == 0) {
+ gcount++;
+ }
+ extinfo->write_gen_counter = OSSwapHostToBigInt32 (gcount);
+
+ SET(cp->c_flag, C_MINOR_MOD);
+ }
+ else {
+ gcount = 0;
+ }
+
+ return gcount;
+}
+
+/*
+ * There is no need for any locks here (other than an iocount on an
+ * associated vnode) because reading and writing an aligned 32 bit
+ * integer should be atomic on all platforms we support.
+ */
+static u_int32_t
+hfs_get_gencount_internal(const uint8_t *finderinfo, mode_t mode)
+{
+ const uint8_t *finfo = NULL;
+ u_int32_t gcount = 0;
+
+ /* overlay the FinderInfo to the correct pointer, and advance */
+ finfo = finderinfo;
+ finfo = finfo + 16;
+
+ /*
+ * FinderInfo is written out in big endian... make sure to convert it to host
+ * native before we use it.
+ *
+ * NOTE: the write_gen_counter is stored in the same location in both the
+ * FndrExtendedFileInfo and FndrExtendedDirInfo structs (it's the
+ * last 32-bit word) so it is safe to have one code path here.
+ */
+ if (S_ISDIR(mode) || S_ISREG(mode)) {
+ const struct FndrExtendedFileInfo *extinfo = (const struct FndrExtendedFileInfo *)finfo;
+ gcount = OSSwapBigToHostInt32 (extinfo->write_gen_counter);
+
+ /*
+ * Is it zero? File might originate in 10.8 or earlier. We lie and bump it to 1,
+ * since the incrementer code is able to handle this case and will double-increment
+ * for us.
+ */
+ if (gcount == 0) {
+ gcount++;
+ }
+ }
+
+ return gcount;
+}
+
+/* Getter for the gen count */
+u_int32_t hfs_get_gencount (struct cnode *cp) {
+ return hfs_get_gencount_internal(cp->c_finderinfo, cp->c_attr.ca_mode);
+}
+
+/* Getter for the gen count from a buffer (currently pointer to finderinfo)*/
+u_int32_t hfs_get_gencount_from_blob (const uint8_t *finfoblob, mode_t mode) {
+ return hfs_get_gencount_internal(finfoblob, mode);
+}
+
+void hfs_clear_might_be_dirty_flag(cnode_t *cp)
+{
+ /*
+ * If we're about to touch both mtime and ctime, we can clear the
+ * C_MIGHT_BE_DIRTY_FROM_MAPPING since we can guarantee that
+ * subsequent page-outs can only be for data made dirty before
+ * now.
+ */
+ CLR(cp->c_flag, C_MIGHT_BE_DIRTY_FROM_MAPPING);
+}
+
/*
* 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)
{
- /* don't modify times if volume is read-only */
- if (hfsmp->hfs_flags & HFS_READ_ONLY) {
+ vfs_context_t ctx;
+
+ if (ISSET(hfsmp->hfs_flags, HFS_READ_ONLY) || ISSET(cp->c_flag, C_NOEXISTS)) {
cp->c_touch_acctime = FALSE;
cp->c_touch_chgtime = FALSE;
cp->c_touch_modtime = FALSE;
+ CLR(cp->c_flag, C_NEEDS_DATEADDED);
+ return;
}
+#if CONFIG_HFS_STD
else if (hfsmp->hfs_flags & HFS_STANDARD) {
/* HFS Standard doesn't support access times */
cp->c_touch_acctime = FALSE;
}
+#endif
+ 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))
+ hfsmp->hfs_freeze_state != HFS_THAWED ||
+ (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) {
+ 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;
+ if (cp->c_touch_modtime && cp->c_touch_chgtime)
+ hfs_clear_might_be_dirty_flag(cp);
+
microtime(&tv);
if (cp->c_touch_acctime) {
- cp->c_atime = tv.tv_sec;
/*
- * When the access time is the only thing changing
- * then make sure its sufficiently newer before
- * committing it to disk.
+ * When the access time is the only thing changing, we
+ * won't necessarily write it to disk immediately. We
+ * only do the atime update at vnode recycle time, when
+ * fsync is called or when there's another reason to write
+ * to the metadata.
*/
- if ((((u_int32_t)cp->c_atime - (u_int32_t)(cp)->c_attr.ca_atimeondisk) >
- ATIME_ONDISK_ACCURACY)) {
- cp->c_flag |= C_MODIFIED;
- }
+ cp->c_atime = tv.tv_sec;
cp->c_touch_acctime = FALSE;
}
if (cp->c_touch_modtime) {
- cp->c_mtime = tv.tv_sec;
cp->c_touch_modtime = FALSE;
- cp->c_flag |= C_MODIFIED;
- touchvol = 1;
-#if 1
+ time_t new_time = tv.tv_sec;
+#if CONFIG_HFS_STD
/*
* HFS dates that WE set must be adjusted for DST
*/
if ((hfsmp->hfs_flags & HFS_STANDARD) && gTimeZone.tz_dsttime) {
- cp->c_mtime += 3600;
+ new_time += 3600;
}
#endif
+ if (cp->c_mtime != new_time) {
+ cp->c_mtime = new_time;
+ cp->c_flag |= C_MINOR_MOD;
+ touchvol = 1;
+ }
}
if (cp->c_touch_chgtime) {
- cp->c_ctime = tv.tv_sec;
cp->c_touch_chgtime = FALSE;
- cp->c_flag |= C_MODIFIED;
+ if (cp->c_ctime != tv.tv_sec) {
+ cp->c_ctime = tv.tv_sec;
+ cp->c_flag |= C_MINOR_MOD;
+ touchvol = 1;
+ }
+ }
+
+ if (cp->c_flag & C_NEEDS_DATEADDED) {
+ hfs_write_dateadded (&(cp->c_attr), tv.tv_sec);
+ cp->c_flag |= C_MINOR_MOD;
+ /* untwiddle the bit */
+ cp->c_flag &= ~C_NEEDS_DATEADDED;
touchvol = 1;
}
/* Touch the volume modtime if needed */
if (touchvol) {
- MarkVCBDirty(hfsmp);
+ hfs_note_header_minor_change(hfsmp);
HFSTOVCB(hfsmp)->vcbLsMod = tv.tv_sec;
}
}
}
+// Use this if you don't want to check the return code
+void hfs_lock_always(cnode_t *cp, enum hfs_locktype locktype)
+{
+ hfs_lock(cp, locktype, HFS_LOCK_ALWAYS);
+}
+
/*
* Lock a cnode.
+ * N.B. If you add any failure cases, *make* sure hfs_lock_always works
*/
-__private_extern__
int
-hfs_lock(struct cnode *cp, enum hfslocktype locktype)
+hfs_lock(struct cnode *cp, enum hfs_locktype locktype, enum hfs_lockflags flags)
{
- void * thread = current_thread();
+ thread_t thread = current_thread();
if (cp->c_lockowner == thread) {
/*
- * Only the extents and bitmap file's support lock recursion.
+ * Only the extents and bitmap files support lock recursion
+ * here. The other system files support lock recursion in
+ * hfs_systemfile_lock. Eventually, we should change to
+ * handle recursion solely in hfs_systemfile_lock.
*/
if ((cp->c_fileid == kHFSExtentsFileID) ||
(cp->c_fileid == kHFSAllocationFileID)) {
lck_rw_lock_shared(&cp->c_rwlock);
cp->c_lockowner = HFS_SHARED_OWNER;
- } else /* HFS_EXCLUSIVE_LOCK */ {
+ } 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.
- */
+ /* Only the extents and bitmap files support lock recursion. */
if ((cp->c_fileid == kHFSExtentsFileID) ||
(cp->c_fileid == kHFSAllocationFileID)) {
cp->c_syslockcount = 1;
#endif /* HFS_CHECK_LOCK_ORDER */
/*
- * Skip cnodes that no longer exist (were deleted).
+ * Skip cnodes for regular files that no longer exist
+ * (marked deleted, catalog entry gone).
*/
- if ((locktype != HFS_FORCE_LOCK) &&
+ if (((flags & HFS_LOCK_ALLOW_NOEXISTS) == 0) &&
((cp->c_desc.cd_flags & CD_ISMETA) == 0) &&
(cp->c_flag & C_NOEXISTS)) {
hfs_unlock(cp);
return (0);
}
+bool hfs_lock_upgrade(cnode_t *cp)
+{
+ if (lck_rw_lock_shared_to_exclusive(&cp->c_rwlock)) {
+ cp->c_lockowner = current_thread();
+ return true;
+ } else
+ return false;
+}
+
/*
* Lock a pair of cnodes.
*/
-__private_extern__
int
-hfs_lockpair(struct cnode *cp1, struct cnode *cp2, enum hfslocktype locktype)
+hfs_lockpair(struct cnode *cp1, struct cnode *cp2, enum hfs_locktype locktype)
{
struct cnode *first, *last;
int error;
* If cnodes match then just lock one.
*/
if (cp1 == cp2) {
- return hfs_lock(cp1, locktype);
+ return hfs_lock(cp1, locktype, HFS_LOCK_DEFAULT);
}
/*
last = cp1;
}
- if ( (error = hfs_lock(first, locktype))) {
+ if ( (error = hfs_lock(first, locktype, HFS_LOCK_DEFAULT))) {
return (error);
}
- if ( (error = hfs_lock(last, locktype))) {
+ if ( (error = hfs_lock(last, locktype, HFS_LOCK_DEFAULT))) {
hfs_unlock(first);
return (error);
}
* - 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 hfs_locktype 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))) {
+ if ((error = hfs_lock(list[i], locktype, HFS_LOCK_DEFAULT))) {
+ /* 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 vp = NULLVP;
- u_int32_t c_flag;
- void *lockowner;
+ vnode_t rvp = NULLVP;
+ vnode_t vp = NULLVP;
+ u_int32_t c_flag;
/*
* Only the extents and bitmap file's support lock recursion.
return;
}
}
- 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 (c_flag & (C_NEED_DVNODE_PUT | C_NEED_DATA_SETSIZE)) {
+ const thread_t thread = current_thread();
+
+ if (cp->c_lockowner == thread) {
+ c_flag = cp->c_flag;
+
+ // If we have the truncate lock, we must defer the puts
+ if (cp->c_truncatelockowner == thread) {
+ if (ISSET(c_flag, C_NEED_DVNODE_PUT)
+ && !cp->c_need_dvnode_put_after_truncate_unlock) {
+ CLR(c_flag, C_NEED_DVNODE_PUT);
+ cp->c_need_dvnode_put_after_truncate_unlock = true;
+ }
+ if (ISSET(c_flag, C_NEED_RVNODE_PUT)
+ && !cp->c_need_rvnode_put_after_truncate_unlock) {
+ CLR(c_flag, C_NEED_RVNODE_PUT);
+ cp->c_need_rvnode_put_after_truncate_unlock = true;
+ }
+ }
+
+ CLR(cp->c_flag, (C_NEED_DATA_SETSIZE | C_NEED_RSRC_SETSIZE
+ | C_NEED_DVNODE_PUT | 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)) {
+ }
+ if (c_flag & (C_NEED_RVNODE_PUT | C_NEED_RSRC_SETSIZE)) {
rvp = cp->c_rsrc_vp;
- }
+ }
- lockowner = cp->c_lockowner;
- if (lockowner == current_thread()) {
cp->c_lockowner = NULL;
lck_rw_unlock_exclusive(&cp->c_rwlock);
} else {
/* 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_DATA_SETSIZE) {
+ ubc_setsize(vp, VTOF(vp)->ff_size);
+#if HFS_COMPRESSION
+ /*
+ * If this is a compressed file, we need to reset the
+ * compression state. We will have set the size to zero
+ * above and it will get fixed up later (in exactly the
+ * same way that new vnodes are fixed up). Note that we
+ * should only be able to get here if the truncate lock is
+ * held exclusively and so we do the reset when that's
+ * unlocked.
+ */
+ decmpfs_cnode *dp = VTOCMP(vp);
+ if (dp && decmpfs_cnode_get_vnode_state(dp) != FILE_TYPE_UNKNOWN)
+ cp->c_need_decmpfs_reset = true;
+#endif
+ }
if (c_flag & C_NEED_DVNODE_PUT)
vnode_put(vp);
}
if (rvp) {
if (c_flag & C_NEED_RSRC_SETSIZE)
- ubc_setsize(rvp, 0);
+ ubc_setsize(rvp, VTOF(rvp)->ff_size);
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 hfs_locktype locktype, enum hfs_lockflags flags)
{
-#ifdef HFS_CHECK_LOCK_ORDER
- if (cp->c_lockowner == current_thread())
- panic("hfs_lock_truncate: cnode %p locked!", cp);
-#endif /* HFS_CHECK_LOCK_ORDER */
+ thread_t thread = current_thread();
- if (exclusive)
- lck_rw_lock_exclusive(&cp->c_truncatelock);
- else
+ if (cp->c_truncatelockowner == thread) {
+ /*
+ * Ignore grabbing the lock if it the current thread already
+ * holds exclusive lock.
+ *
+ * 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 ((flags & HFS_LOCK_SKIP_IF_EXCLUSIVE) == 0) {
+ panic("hfs_lock_truncate: cnode %p locked!", cp);
+ }
+ } else if (locktype == HFS_SHARED_LOCK) {
lck_rw_lock_shared(&cp->c_truncatelock);
+ cp->c_truncatelockowner = HFS_SHARED_OWNER;
+ } else { /* HFS_EXCLUSIVE_LOCK */
+ lck_rw_lock_exclusive(&cp->c_truncatelock);
+ cp->c_truncatelockowner = thread;
+ }
}
-__private_extern__
-void
-hfs_unlock_truncate(struct cnode *cp, int exclusive)
+bool hfs_truncate_lock_upgrade(struct cnode *cp)
{
- if (exclusive) {
- lck_rw_unlock_exclusive(&cp->c_truncatelock);
- } else {
- lck_rw_unlock_shared(&cp->c_truncatelock);
- }
+ assert(cp->c_truncatelockowner == HFS_SHARED_OWNER);
+ if (!lck_rw_lock_shared_to_exclusive(&cp->c_truncatelock))
+ return false;
+ cp->c_truncatelockowner = current_thread();
+ return true;
+}
+
+void hfs_truncate_lock_downgrade(struct cnode *cp)
+{
+ assert(cp->c_truncatelockowner == current_thread());
+ lck_rw_lock_exclusive_to_shared(&cp->c_truncatelock);
+ cp->c_truncatelockowner = HFS_SHARED_OWNER;
+}
+
+/*
+ * 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 hfs_locktype locktype, enum hfs_lockflags flags)
+{
+ thread_t thread = current_thread();
+ boolean_t didlock = false;
+
+ if (cp->c_truncatelockowner == thread) {
+ /*
+ * Ignore grabbing the lock if the current thread already
+ * holds exclusive lock.
+ *
+ * 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 ((flags & HFS_LOCK_SKIP_IF_EXCLUSIVE) == 0) {
+ panic("hfs_lock_truncate: cnode %p locked!", cp);
+ }
+ } else if (locktype == HFS_SHARED_LOCK) {
+ didlock = lck_rw_try_lock(&cp->c_truncatelock, LCK_RW_TYPE_SHARED);
+ if (didlock) {
+ cp->c_truncatelockowner = HFS_SHARED_OWNER;
+ }
+ } else { /* 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.
+ *
+ * If HFS_LOCK_SKIP_IF_EXCLUSIVE flag was set, it means that a previous
+ * hfs_lock_truncate() might have skipped grabbing a lock because
+ * the current thread was already holding the lock exclusive and
+ * we may need to return from this function without actually unlocking
+ * the truncate lock.
+ */
+void
+hfs_unlock_truncate(struct cnode *cp, enum hfs_lockflags flags)
+{
+ thread_t thread = current_thread();
+
+ /*
+ * If HFS_LOCK_SKIP_IF_EXCLUSIVE is set in the flags AND the current
+ * lock owner of the truncate lock is our current thread, then
+ * we must have skipped taking the lock earlier by in
+ * hfs_lock_truncate() by setting HFS_LOCK_SKIP_IF_EXCLUSIVE in the
+ * flags (as the current thread was current lock owner).
+ *
+ * If HFS_LOCK_SKIP_IF_EXCLUSIVE is not set (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 (flags & HFS_LOCK_SKIP_IF_EXCLUSIVE) {
+ if (cp->c_truncatelockowner == thread) {
+ return;
+ }
+ }
+
+ /* HFS_LOCK_EXCLUSIVE */
+ if (thread == cp->c_truncatelockowner) {
+ vnode_t vp = NULL, rvp = NULL;
+
+ /*
+ * If there are pending set sizes, the cnode lock should be dropped
+ * first.
+ */
+#if DEBUG
+ assert(!(cp->c_lockowner == thread
+ && ISSET(cp->c_flag, C_NEED_DATA_SETSIZE | C_NEED_RSRC_SETSIZE)));
+#elif DEVELOPMENT
+ if (cp->c_lockowner == thread
+ && ISSET(cp->c_flag, C_NEED_DATA_SETSIZE | C_NEED_RSRC_SETSIZE)) {
+ printf("hfs: hfs_unlock_truncate called with C_NEED_DATA/RSRC_SETSIZE set (caller: 0x%llx)\n",
+ (uint64_t)VM_KERNEL_UNSLIDE(__builtin_return_address(0)));
+ }
+#endif
+
+ if (cp->c_need_dvnode_put_after_truncate_unlock) {
+ vp = cp->c_vp;
+ cp->c_need_dvnode_put_after_truncate_unlock = false;
+ }
+ if (cp->c_need_rvnode_put_after_truncate_unlock) {
+ rvp = cp->c_rsrc_vp;
+ cp->c_need_rvnode_put_after_truncate_unlock = false;
+ }
+#if HFS_COMPRESSION
+ bool reset_decmpfs = cp->c_need_decmpfs_reset;
+ cp->c_need_decmpfs_reset = false;
+#endif
+
+ cp->c_truncatelockowner = NULL;
+ lck_rw_unlock_exclusive(&cp->c_truncatelock);
+
+#if HFS_COMPRESSION
+ if (reset_decmpfs) {
+ decmpfs_cnode *dp = cp->c_decmp;
+ if (dp && decmpfs_cnode_get_vnode_state(dp) != FILE_TYPE_UNKNOWN)
+ decmpfs_cnode_set_vnode_state(dp, FILE_TYPE_UNKNOWN, 0);
+ }
+#endif
+ // Do the puts now
+ if (vp)
+ vnode_put(vp);
+ if (rvp)
+ vnode_put(rvp);
+ } else { /* HFS_LOCK_SHARED */
+ lck_rw_unlock_shared(&cp->c_truncatelock);
+ }
+}
projects / apple / xnu.git / blobdiff