+
+
+/*
+ * Flush the contents of the journal to the disk.
+ *
+ * Input:
+ * wait_for_IO -
+ * If TRUE, wait to write in-memory journal to the disk
+ * consistently, and also wait to write all asynchronous
+ * metadata blocks to its corresponding locations
+ * consistently on the disk. This means that the journal
+ * is empty at this point and does not contain any
+ * transactions. This is overkill in normal scenarios
+ * but is useful whenever the metadata blocks are required
+ * to be consistent on-disk instead of just the journal
+ * being consistent; like before live verification
+ * and live volume resizing.
+ *
+ * If FALSE, only wait to write in-memory journal to the
+ * disk consistently. This means that the journal still
+ * contains uncommitted transactions and the file system
+ * metadata blocks in the journal transactions might be
+ * written asynchronously to the disk. But there is no
+ * guarantee that they are written to the disk before
+ * returning to the caller. Note that this option is
+ * sufficient for file system data integrity as it
+ * guarantees consistent journal content on the disk.
+ */
+int
+hfs_journal_flush(struct hfsmount *hfsmp, boolean_t wait_for_IO)
+{
+ int ret;
+
+ /* Only peek at hfsmp->jnl while holding the global lock */
+ hfs_lock_global (hfsmp, HFS_SHARED_LOCK);
+ if (hfsmp->jnl) {
+ ret = journal_flush(hfsmp->jnl, wait_for_IO);
+ } else {
+ ret = 0;
+ }
+ hfs_unlock_global (hfsmp);
+
+ return ret;
+}
+
+
+/*
+ * hfs_erase_unused_nodes
+ *
+ * Check wheter a volume may suffer from unused Catalog B-tree nodes that
+ * are not zeroed (due to <rdar://problem/6947811>). If so, just write
+ * zeroes to the unused nodes.
+ *
+ * How do we detect when a volume needs this repair? We can't always be
+ * certain. If a volume was created after a certain date, then it may have
+ * been created with the faulty newfs_hfs. Since newfs_hfs only created one
+ * clump, we can assume that if a Catalog B-tree is larger than its clump size,
+ * that means that the entire first clump must have been written to, which means
+ * there shouldn't be unused and unwritten nodes in that first clump, and this
+ * repair is not needed.
+ *
+ * We have defined a bit in the Volume Header's attributes to indicate when the
+ * unused nodes have been repaired. A newer newfs_hfs will set this bit.
+ * As will fsck_hfs when it repairs the unused nodes.
+ */
+int hfs_erase_unused_nodes(struct hfsmount *hfsmp)
+{
+ int result;
+ struct filefork *catalog;
+ int lockflags;
+
+ if (hfsmp->vcbAtrb & kHFSUnusedNodeFixMask)
+ {
+ /* This volume has already been checked and repaired. */
+ return 0;
+ }
+
+ if ((hfsmp->localCreateDate < kHFSUnusedNodesFixDate))
+ {
+ /* This volume is too old to have had the problem. */
+ hfsmp->vcbAtrb |= kHFSUnusedNodeFixMask;
+ return 0;
+ }
+
+ catalog = hfsmp->hfs_catalog_cp->c_datafork;
+ if (catalog->ff_size > catalog->ff_clumpsize)
+ {
+ /* The entire first clump must have been in use at some point. */
+ hfsmp->vcbAtrb |= kHFSUnusedNodeFixMask;
+ return 0;
+ }
+
+ /*
+ * If we get here, we need to zero out those unused nodes.
+ *
+ * We start a transaction and lock the catalog since we're going to be
+ * making on-disk changes. But note that BTZeroUnusedNodes doens't actually
+ * do its writing via the journal, because that would be too much I/O
+ * to fit in a transaction, and it's a pain to break it up into multiple
+ * transactions. (It behaves more like growing a B-tree would.)
+ */
+ printf("hfs_erase_unused_nodes: updating volume %s.\n", hfsmp->vcbVN);
+ result = hfs_start_transaction(hfsmp);
+ if (result)
+ goto done;
+ lockflags = hfs_systemfile_lock(hfsmp, SFL_CATALOG, HFS_EXCLUSIVE_LOCK);
+ result = BTZeroUnusedNodes(catalog);
+ vnode_waitforwrites(hfsmp->hfs_catalog_vp, 0, 0, 0, "hfs_erase_unused_nodes");
+ hfs_systemfile_unlock(hfsmp, lockflags);
+ hfs_end_transaction(hfsmp);
+ if (result == 0)
+ hfsmp->vcbAtrb |= kHFSUnusedNodeFixMask;
+ printf("hfs_erase_unused_nodes: done updating volume %s.\n", hfsmp->vcbVN);
+
+done:
+ return result;
+}
+
+
+extern time_t snapshot_timestamp;
+
+int
+check_for_tracked_file(struct vnode *vp, time_t ctime, uint64_t op_type, void *arg)
+{
+ int tracked_error = 0, snapshot_error = 0;
+
+ if (vp == NULL) {
+ return 0;
+ }
+
+ if (VTOC(vp)->c_flags & UF_TRACKED) {
+ // the file has the tracked bit set, so send an event to the tracked-file handler
+ int error;
+
+ // printf("hfs: tracked-file: encountered a file with the tracked bit set! (vp %p)\n", vp);
+ error = resolve_nspace_item(vp, op_type | NAMESPACE_HANDLER_TRACK_EVENT);
+ if (error) {
+ if (error == EAGAIN) {
+ printf("hfs: tracked-file: timed out waiting for namespace handler...\n");
+
+ } else if (error == EINTR) {
+ // printf("hfs: tracked-file: got a signal while waiting for namespace handler...\n");
+ tracked_error = EINTR;
+ }
+ }
+ }
+
+ if (ctime != 0 && snapshot_timestamp != 0 && (ctime <= snapshot_timestamp || vnode_needssnapshots(vp))) {
+ // the change time is within this epoch
+ int error;
+
+ error = resolve_nspace_item_ext(vp, op_type | NAMESPACE_HANDLER_SNAPSHOT_EVENT, arg);
+ if (error == EDEADLK) {
+ snapshot_error = 0;
+ } else if (error) {
+ if (error == EAGAIN) {
+ printf("hfs: cow-snapshot: timed out waiting for namespace handler...\n");
+ } else if (error == EINTR) {
+ // printf("hfs: cow-snapshot: got a signal while waiting for namespace handler...\n");
+ snapshot_error = EINTR;
+ }
+ }
+ }
+
+ if (tracked_error) return tracked_error;
+ if (snapshot_error) return snapshot_error;
+
+ return 0;
+}
+
+int
+check_for_dataless_file(struct vnode *vp, uint64_t op_type)
+{
+ int error;
+
+ if (vp == NULL || (VTOC(vp)->c_flags & UF_COMPRESSED) == 0 || VTOCMP(vp) == NULL || VTOCMP(vp)->cmp_type != DATALESS_CMPFS_TYPE) {
+ // there's nothing to do, it's not dataless
+ return 0;
+ }
+
+ // printf("hfs: dataless: encountered a file with the dataless bit set! (vp %p)\n", vp);
+ error = resolve_nspace_item(vp, op_type | NAMESPACE_HANDLER_NSPACE_EVENT);
+ if (error == EDEADLK && op_type == NAMESPACE_HANDLER_WRITE_OP) {
+ error = 0;
+ } else if (error) {
+ if (error == EAGAIN) {
+ printf("hfs: dataless: timed out waiting for namespace handler...\n");
+ // XXXdbg - return the fabled ENOTPRESENT (i.e. EJUKEBOX)?
+ return 0;
+ } else if (error == EINTR) {
+ // printf("hfs: dataless: got a signal while waiting for namespace handler...\n");
+ return EINTR;
+ }
+ } else if (VTOC(vp)->c_flags & UF_COMPRESSED) {
+ //
+ // if we're here, the dataless bit is still set on the file
+ // which means it didn't get handled. we return an error
+ // but it's presently ignored by all callers of this function.
+ //
+ // XXXdbg - EDATANOTPRESENT is what we really need...
+ //
+ return EBADF;
+ }
+
+ return error;
+}
projects / apple / xnu.git / blobdiff