btrfs-progs: minor source sync with kernel 6.4

Sync a few more file on the source level with kernel 6.4, no functional
changes.

Signed-off-by: David Sterba <dsterba@suse.com>

kernel-shared/compression.h

@@ -12,6 +12,8 @@ struct btrfs_inode;
 struct address_space;
 struct inode;
 struct bio;
+/* Stub for kernel-user parity. */
+struct btrfs_bio { };
 
 /*
  * We want to make sure that amount of RAM required to uncompress an extent is
@@ -58,6 +60,9 @@ struct compressed_bio {
 		struct btrfs_bio *orig_bbio;
 		struct work_struct write_end_work;
 	};
+
+	/* Must be last. */
+	struct btrfs_bio bbio;
 };
 
 static inline unsigned int btrfs_compress_type(unsigned int type_level)

kernel-shared/ctree.c

@@ -233,13 +233,35 @@ noinline void btrfs_release_path(struct btrfs_path *p)
 	int i;
 
 	for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
+		p->slots[i] = 0;
 		if (!p->nodes[i])
 			continue;
+		if (p->locks[i]) {
+			btrfs_tree_unlock_rw(p->nodes[i], p->locks[i]);
+			p->locks[i] = 0;
+		}
 		free_extent_buffer(p->nodes[i]);
+		p->nodes[i] = NULL;
 	}
 	memset(p, 0, sizeof(*p));
 }
 
+/*
+ * We want the transaction abort to print stack trace only for errors where the
+ * cause could be a bug, eg. due to ENOSPC, and not for common errors that are
+ * caused by external factors.
+ */
+bool __cold abort_should_print_stack(int errno)
+{
+	switch (errno) {
+	case -EIO:
+	case -EROFS:
+	case -ENOMEM:
+		return false;
+	}
+	return true;
+}
+
 void add_root_to_dirty_list(struct btrfs_root *root)
 {
 	if (test_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state) &&
@@ -289,6 +311,7 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
 		btrfs_item_key(buf, &disk_key, 0);
 	else
 		btrfs_node_key(buf, &disk_key, 0);
+
 	cow = btrfs_alloc_tree_block(trans, new_root, buf->len,
 				     new_root_objectid, &disk_key,
 				     level, buf->start, 0,
@@ -451,10 +474,9 @@ static int btrfs_block_can_be_shared(struct btrfs_root *root,
 			             struct extent_buffer *buf)
 {
 	/*
-	 * Tree blocks not in reference counted trees and tree roots
-	 * are never shared. If a block was allocated after the last
-	 * snapshot and the block was not allocated by tree relocation,
-	 * we know the block is not shared.
+	 * Tree blocks not in shareable trees and tree roots are never shared.
+	 * If a block was allocated after the last snapshot and the block was
+	 * not allocated by tree relocation, we know the block is not shared.
 	 */
 	if (test_bit(BTRFS_ROOT_SHAREABLE, &root->state) &&
 	    buf != root->node && buf != root->commit_root &&
@@ -462,6 +484,7 @@ static int btrfs_block_can_be_shared(struct btrfs_root *root,
 	     btrfs_root_last_snapshot(&root->root_item) ||
 	     btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC)))
 		return 1;
+
 	return 0;
 }
 
@@ -557,7 +580,19 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
 	return 0;
 }
 
-static int __btrfs_cow_block(struct btrfs_trans_handle *trans,
+/*
+ * does the dirty work in cow of a single block.  The parent block (if
+ * supplied) is updated to point to the new cow copy.  The new buffer is marked
+ * dirty and returned locked.  If you modify the block it needs to be marked
+ * dirty again.
+ *
+ * search_start -- an allocation hint for the new block
+ *
+ * empty_size -- a hint that you plan on doing more cow.  This is the size in
+ * bytes the allocator should try to find free next to the block it returns.
+ * This is just a hint and may be ignored by the allocator.
+ */
+static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
 			     struct btrfs_root *root,
 			     struct extent_buffer *buf,
 			     struct extent_buffer *parent, int parent_slot,
@@ -679,7 +714,24 @@ int btrfs_cow_block(struct btrfs_trans_handle *trans,
 	return ret;
 }
 
-int btrfs_comp_cpu_keys(const struct btrfs_key *k1, const struct btrfs_key *k2)
+/*
+ * helper function for defrag to decide if two blocks pointed to by a
+ * node are actually close by
+ */
+static __attribute__((unused)) int close_blocks(u64 blocknr, u64 other, u32 blocksize)
+{
+	if (blocknr < other && other - (blocknr + blocksize) < 32768)
+		return 1;
+	if (blocknr > other && blocknr - (other + blocksize) < 32768)
+		return 1;
+	return 0;
+}
+
+
+/*
+ * same as comp_keys only with two btrfs_key's
+ */
+int __pure btrfs_comp_cpu_keys(const struct btrfs_key *k1, const struct btrfs_key *k2)
 {
 	if (k1->objectid > k2->objectid)
 		return 1;
@@ -818,15 +870,20 @@ struct extent_buffer *read_node_slot(struct btrfs_fs_info *fs_info,
 	return ret;
 }
 
-static int balance_level(struct btrfs_trans_handle *trans,
+/*
+ * node level balancing, used to make sure nodes are in proper order for
+ * item deletion.  We balance from the top down, so we have to make sure
+ * that a deletion won't leave an node completely empty later on.
+ */
+static noinline int balance_level(struct btrfs_trans_handle *trans,
 			 struct btrfs_root *root,
 			 struct btrfs_path *path, int level)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct extent_buffer *right = NULL;
 	struct extent_buffer *mid;
 	struct extent_buffer *left = NULL;
 	struct extent_buffer *parent = NULL;
-	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret = 0;
 	int wret;
 	int pslot;
@@ -1013,16 +1070,19 @@ enospc:
 	return ret;
 }
 
-/* returns zero if the push worked, non-zero otherwise */
-static int noinline push_nodes_for_insert(struct btrfs_trans_handle *trans,
+/* Node balancing for insertion.  Here we only split or push nodes around
+ * when they are completely full.  This is also done top down, so we
+ * have to be pessimistic.
+ */
+static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
 					  struct btrfs_root *root,
 					  struct btrfs_path *path, int level)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct extent_buffer *right = NULL;
 	struct extent_buffer *mid;
 	struct extent_buffer *left = NULL;
 	struct extent_buffer *parent = NULL;
-	struct btrfs_fs_info *fs_info = root->fs_info;
 	int ret = 0;
 	int wret;
 	int pslot;
@@ -1128,11 +1188,12 @@ static int noinline push_nodes_for_insert(struct btrfs_trans_handle *trans,
 }
 
 /*
- * readahead one full node of leaves
+ * readahead one full node of leaves, finding things that are close
+ * to the block in 'slot', and triggering ra on them.
  */
 static void reada_for_search(struct btrfs_fs_info *fs_info,
-			     struct btrfs_path *path, int level, int slot,
-			     u64 objectid)
+			     struct btrfs_path *path,
+			     int level, int slot, u64 objectid)
 {
 	struct extent_buffer *node;
 	struct btrfs_disk_key disk_key;

kernel-shared/ctree.h

@@ -22,6 +22,7 @@
 #include <stdbool.h>
 
 #include "kernel-lib/list.h"
+#include "kernel-lib/rbtree.h"
 #include "kerncompat.h"
 #include "common/extent-cache.h"
 #include "kernel-shared/uapi/btrfs.h"
@@ -148,13 +149,20 @@ enum {
 	READA_FORWARD_ALWAYS,
 };
 
+/*
+ * btrfs_paths remember the path taken from the root down to the leaf.
+ * level 0 is always the leaf, and nodes[1...BTRFS_MAX_LEVEL] will point
+ * to any other levels that are present.
+ *
+ * The slots array records the index of the item or block pointer
+ * used while walking the tree.
+ */
 struct btrfs_path {
 	struct extent_buffer *nodes[BTRFS_MAX_LEVEL];
 	int slots[BTRFS_MAX_LEVEL];
 	/* The kernel locking scheme is not done in userspace. */
-	int locks[BTRFS_MAX_LEVEL];
-
-	signed char reada;
+	u8 locks[BTRFS_MAX_LEVEL];
+	u8 reada;
 	/* keep some upper locks as we walk down */
 	u8 lowest_level;
 
@@ -477,16 +485,21 @@ enum {
  * and for the extent tree extent_root root.
  */
 struct btrfs_root {
+	struct rb_node rb_node;
+
 	struct extent_buffer *node;
+
 	struct extent_buffer *commit_root;
+	struct btrfs_root *log_root;
+	struct btrfs_root *reloc_root;
+
+	unsigned long state;
 	struct btrfs_root_item root_item;
 	struct btrfs_key root_key;
 	struct btrfs_fs_info *fs_info;
 	u64 objectid;
 	u64 last_trans;
 
-	unsigned long state;
-
 	u32 type;
 	u64 last_inode_alloc;
 
@@ -494,7 +507,6 @@ struct btrfs_root {
 
 	/* the dirty list is only used by non-reference counted roots */
 	struct list_head dirty_list;
-	struct rb_node rb_node;
 
 	spinlock_t accounting_lock;
 };

kernel-shared/delayed-ref.c

@@ -138,10 +138,9 @@ static struct btrfs_delayed_ref_node* tree_insert(struct rb_root *root,
 }
 
 /*
- * find an head entry based on bytenr. This returns the delayed ref
- * head if it was able to find one, or NULL if nothing was in that spot.
- * If return_bigger is given, the next bigger entry is returned if no exact
- * match is found.
+ * Find a head entry based on bytenr. This returns the delayed ref head if it
+ * was able to find one, or NULL if nothing was in that spot.  If return_bigger
+ * is given, the next bigger entry is returned if no exact match is found.
  */
 static struct btrfs_delayed_ref_head *
 find_ref_head(struct rb_root *root, u64 bytenr,

kernel-shared/dir-item.c

@@ -21,6 +21,14 @@
 #include "kernel-shared/disk-io.h"
 #include "kernel-shared/transaction.h"
 
+/*
+ * insert a name into a directory, doing overflow properly if there is a hash
+ * collision.  data_size indicates how big the item inserted should be.  On
+ * success a struct btrfs_dir_item pointer is returned, otherwise it is
+ * an ERR_PTR.
+ *
+ * The name is not copied into the dir item, you have to do that yourself.
+ */
 static struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle
 						   *trans,
 						   struct btrfs_root *root,
@@ -53,6 +61,10 @@ static struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle
 	return (struct btrfs_dir_item *)ptr;
 }
 
+/*
+ * xattrs work a lot like directories, this inserts an xattr item
+ * into the tree
+ */
 int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans,
 			    struct btrfs_root *root, const char *name,
 			    u16 name_len, const void *data, u16 data_len,
@@ -103,6 +115,14 @@ int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans,
 	return ret;
 }
 
+/*
+ * insert a directory item in the tree, doing all the magic for
+ * both indexes. 'dir' indicates which objectid to insert it into,
+ * 'location' is the key to stuff into the directory item, 'type' is the
+ * type of the inode we're pointing to, and 'index' is the sequence number
+ * to use for the second index (if one is created).
+ * Will return 0 or -ENOMEM
+ */
 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
 			  *root, const char *name, int name_len, u64 dir,
 			  struct btrfs_key *location, u8 type, u64 index)

kernel-shared/root-tree.c

@@ -195,7 +195,6 @@ int btrfs_add_root_ref(struct btrfs_trans_handle *trans,
 	struct extent_buffer *leaf;
 	unsigned long ptr;
 
-
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;