1 files changed, 534 insertions, 0 deletions

diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
new file mode 100644
index 0000000000..bda1fdbba6
--- /dev/null
+++ b/fs/btrfs/btrfs_inode.h
@@ -0,0 +1,534 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2007 Oracle.  All rights reserved.
+ */
+
+#ifndef BTRFS_INODE_H
+#define BTRFS_INODE_H
+
+#include <linux/hash.h>
+#include <linux/refcount.h>
+#include "extent_map.h"
+#include "extent_io.h"
+#include "ordered-data.h"
+#include "delayed-inode.h"
+
+/*
+ * Since we search a directory based on f_pos (struct dir_context::pos) we have
+ * to start at 2 since '.' and '..' have f_pos of 0 and 1 respectively, so
+ * everybody else has to start at 2 (see btrfs_real_readdir() and dir_emit_dots()).
+ */
+#define BTRFS_DIR_START_INDEX 2
+
+/*
+ * ordered_data_close is set by truncate when a file that used
+ * to have good data has been truncated to zero.  When it is set
+ * the btrfs file release call will add this inode to the
+ * ordered operations list so that we make sure to flush out any
+ * new data the application may have written before commit.
+ */
+enum {
+	BTRFS_INODE_FLUSH_ON_CLOSE,
+	BTRFS_INODE_DUMMY,
+	BTRFS_INODE_IN_DEFRAG,
+	BTRFS_INODE_HAS_ASYNC_EXTENT,
+	 /*
+	  * Always set under the VFS' inode lock, otherwise it can cause races
+	  * during fsync (we start as a fast fsync and then end up in a full
+	  * fsync racing with ordered extent completion).
+	  */
+	BTRFS_INODE_NEEDS_FULL_SYNC,
+	BTRFS_INODE_COPY_EVERYTHING,
+	BTRFS_INODE_IN_DELALLOC_LIST,
+	BTRFS_INODE_HAS_PROPS,
+	BTRFS_INODE_SNAPSHOT_FLUSH,
+	/*
+	 * Set and used when logging an inode and it serves to signal that an
+	 * inode does not have xattrs, so subsequent fsyncs can avoid searching
+	 * for xattrs to log. This bit must be cleared whenever a xattr is added
+	 * to an inode.
+	 */
+	BTRFS_INODE_NO_XATTRS,
+	/*
+	 * Set when we are in a context where we need to start a transaction and
+	 * have dirty pages with the respective file range locked. This is to
+	 * ensure that when reserving space for the transaction, if we are low
+	 * on available space and need to flush delalloc, we will not flush
+	 * delalloc for this inode, because that could result in a deadlock (on
+	 * the file range, inode's io_tree).
+	 */
+	BTRFS_INODE_NO_DELALLOC_FLUSH,
+	/*
+	 * Set when we are working on enabling verity for a file. Computing and
+	 * writing the whole Merkle tree can take a while so we want to prevent
+	 * races where two separate tasks attempt to simultaneously start verity
+	 * on the same file.
+	 */
+	BTRFS_INODE_VERITY_IN_PROGRESS,
+	/* Set when this inode is a free space inode. */
+	BTRFS_INODE_FREE_SPACE_INODE,
+};
+
+/* in memory btrfs inode */
+struct btrfs_inode {
+	/* which subvolume this inode belongs to */
+	struct btrfs_root *root;
+
+	/* key used to find this inode on disk.  This is used by the code
+	 * to read in roots of subvolumes
+	 */
+	struct btrfs_key location;
+
+	/*
+	 * Lock for counters and all fields used to determine if the inode is in
+	 * the log or not (last_trans, last_sub_trans, last_log_commit,
+	 * logged_trans), to access/update new_delalloc_bytes and to update the
+	 * VFS' inode number of bytes used.
+	 */
+	spinlock_t lock;
+
+	/* the extent_tree has caches of all the extent mappings to disk */
+	struct extent_map_tree extent_tree;
+
+	/* the io_tree does range state (DIRTY, LOCKED etc) */
+	struct extent_io_tree io_tree;
+
+	/*
+	 * Keep track of where the inode has extent items mapped in order to
+	 * make sure the i_size adjustments are accurate
+	 */
+	struct extent_io_tree file_extent_tree;
+
+	/* held while logging the inode in tree-log.c */
+	struct mutex log_mutex;
+
+	/* used to order data wrt metadata */
+	struct btrfs_ordered_inode_tree ordered_tree;
+
+	/* list of all the delalloc inodes in the FS.  There are times we need
+	 * to write all the delalloc pages to disk, and this list is used
+	 * to walk them all.
+	 */
+	struct list_head delalloc_inodes;
+
+	/* node for the red-black tree that links inodes in subvolume root */
+	struct rb_node rb_node;
+
+	unsigned long runtime_flags;
+
+	/* full 64 bit generation number, struct vfs_inode doesn't have a big
+	 * enough field for this.
+	 */
+	u64 generation;
+
+	/*
+	 * transid of the trans_handle that last modified this inode
+	 */
+	u64 last_trans;
+
+	/*
+	 * transid that last logged this inode
+	 */
+	u64 logged_trans;
+
+	/*
+	 * log transid when this inode was last modified
+	 */
+	int last_sub_trans;
+
+	/* a local copy of root's last_log_commit */
+	int last_log_commit;
+
+	union {
+		/*
+		 * Total number of bytes pending delalloc, used by stat to
+		 * calculate the real block usage of the file. This is used
+		 * only for files.
+		 */
+		u64 delalloc_bytes;
+		/*
+		 * The lowest possible index of the next dir index key which
+		 * points to an inode that needs to be logged.
+		 * This is used only for directories.
+		 * Use the helpers btrfs_get_first_dir_index_to_log() and
+		 * btrfs_set_first_dir_index_to_log() to access this field.
+		 */
+		u64 first_dir_index_to_log;
+	};
+
+	union {
+		/*
+		 * Total number of bytes pending delalloc that fall within a file
+		 * range that is either a hole or beyond EOF (and no prealloc extent
+		 * exists in the range). This is always <= delalloc_bytes and this
+		 * is used only for files.
+		 */
+		u64 new_delalloc_bytes;
+		/*
+		 * The offset of the last dir index key that was logged.
+		 * This is used only for directories.
+		 */
+		u64 last_dir_index_offset;
+	};
+
+	/*
+	 * total number of bytes pending defrag, used by stat to check whether
+	 * it needs COW.
+	 */
+	u64 defrag_bytes;
+
+	/*
+	 * the size of the file stored in the metadata on disk.  data=ordered
+	 * means the in-memory i_size might be larger than the size on disk
+	 * because not all the blocks are written yet.
+	 */
+	u64 disk_i_size;
+
+	/*
+	 * If this is a directory then index_cnt is the counter for the index
+	 * number for new files that are created. For an empty directory, this
+	 * must be initialized to BTRFS_DIR_START_INDEX.
+	 */
+	u64 index_cnt;
+
+	/* Cache the directory index number to speed the dir/file remove */
+	u64 dir_index;
+
+	/* the fsync log has some corner cases that mean we have to check
+	 * directories to see if any unlinks have been done before
+	 * the directory was logged.  See tree-log.c for all the
+	 * details
+	 */
+	u64 last_unlink_trans;
+
+	/*
+	 * The id/generation of the last transaction where this inode was
+	 * either the source or the destination of a clone/dedupe operation.
+	 * Used when logging an inode to know if there are shared extents that
+	 * need special care when logging checksum items, to avoid duplicate
+	 * checksum items in a log (which can lead to a corruption where we end
+	 * up with missing checksum ranges after log replay).
+	 * Protected by the vfs inode lock.
+	 */
+	u64 last_reflink_trans;
+
+	/*
+	 * Number of bytes outstanding that are going to need csums.  This is
+	 * used in ENOSPC accounting.
+	 */
+	u64 csum_bytes;
+
+	/* Backwards incompatible flags, lower half of inode_item::flags  */
+	u32 flags;
+	/* Read-only compatibility flags, upper half of inode_item::flags */
+	u32 ro_flags;
+
+	/*
+	 * Counters to keep track of the number of extent item's we may use due
+	 * to delalloc and such.  outstanding_extents is the number of extent
+	 * items we think we'll end up using, and reserved_extents is the number
+	 * of extent items we've reserved metadata for.
+	 */
+	unsigned outstanding_extents;
+
+	struct btrfs_block_rsv block_rsv;
+
+	/*
+	 * Cached values of inode properties
+	 */
+	unsigned prop_compress;		/* per-file compression algorithm */
+	/*
+	 * Force compression on the file using the defrag ioctl, could be
+	 * different from prop_compress and takes precedence if set
+	 */
+	unsigned defrag_compress;
+
+	struct btrfs_delayed_node *delayed_node;
+
+	/* File creation time. */
+	struct timespec64 i_otime;
+
+	/* Hook into fs_info->delayed_iputs */
+	struct list_head delayed_iput;
+
+	struct rw_semaphore i_mmap_lock;
+	struct inode vfs_inode;
+};
+
+static inline u64 btrfs_get_first_dir_index_to_log(const struct btrfs_inode *inode)
+{
+	return READ_ONCE(inode->first_dir_index_to_log);
+}
+
+static inline void btrfs_set_first_dir_index_to_log(struct btrfs_inode *inode,
+						    u64 index)
+{
+	WRITE_ONCE(inode->first_dir_index_to_log, index);
+}
+
+static inline struct btrfs_inode *BTRFS_I(const struct inode *inode)
+{
+	return container_of(inode, struct btrfs_inode, vfs_inode);
+}
+
+static inline unsigned long btrfs_inode_hash(u64 objectid,
+					     const struct btrfs_root *root)
+{
+	u64 h = objectid ^ (root->root_key.objectid * GOLDEN_RATIO_PRIME);
+
+#if BITS_PER_LONG == 32
+	h = (h >> 32) ^ (h & 0xffffffff);
+#endif
+
+	return (unsigned long)h;
+}
+
+#if BITS_PER_LONG == 32
+
+/*
+ * On 32 bit systems the i_ino of struct inode is 32 bits (unsigned long), so
+ * we use the inode's location objectid which is a u64 to avoid truncation.
+ */
+static inline u64 btrfs_ino(const struct btrfs_inode *inode)
+{
+	u64 ino = inode->location.objectid;
+
+	/* type == BTRFS_ROOT_ITEM_KEY: subvol dir */
+	if (inode->location.type == BTRFS_ROOT_ITEM_KEY)
+		ino = inode->vfs_inode.i_ino;
+	return ino;
+}
+
+#else
+
+static inline u64 btrfs_ino(const struct btrfs_inode *inode)
+{
+	return inode->vfs_inode.i_ino;
+}
+
+#endif
+
+static inline void btrfs_i_size_write(struct btrfs_inode *inode, u64 size)
+{
+	i_size_write(&inode->vfs_inode, size);
+	inode->disk_i_size = size;
+}
+
+static inline bool btrfs_is_free_space_inode(struct btrfs_inode *inode)
+{
+	return test_bit(BTRFS_INODE_FREE_SPACE_INODE, &inode->runtime_flags);
+}
+
+static inline bool is_data_inode(struct inode *inode)
+{
+	return btrfs_ino(BTRFS_I(inode)) != BTRFS_BTREE_INODE_OBJECTID;
+}
+
+static inline void btrfs_mod_outstanding_extents(struct btrfs_inode *inode,
+						 int mod)
+{
+	lockdep_assert_held(&inode->lock);
+	inode->outstanding_extents += mod;
+	if (btrfs_is_free_space_inode(inode))
+		return;
+	trace_btrfs_inode_mod_outstanding_extents(inode->root, btrfs_ino(inode),
+						  mod, inode->outstanding_extents);
+}
+
+/*
+ * Called every time after doing a buffered, direct IO or memory mapped write.
+ *
+ * This is to ensure that if we write to a file that was previously fsynced in
+ * the current transaction, then try to fsync it again in the same transaction,
+ * we will know that there were changes in the file and that it needs to be
+ * logged.
+ */
+static inline void btrfs_set_inode_last_sub_trans(struct btrfs_inode *inode)
+{
+	spin_lock(&inode->lock);
+	inode->last_sub_trans = inode->root->log_transid;
+	spin_unlock(&inode->lock);
+}
+
+/*
+ * Should be called while holding the inode's VFS lock in exclusive mode or in a
+ * context where no one else can access the inode concurrently (during inode
+ * creation or when loading an inode from disk).
+ */
+static inline void btrfs_set_inode_full_sync(struct btrfs_inode *inode)
+{
+	set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags);
+	/*
+	 * The inode may have been part of a reflink operation in the last
+	 * transaction that modified it, and then a fsync has reset the
+	 * last_reflink_trans to avoid subsequent fsyncs in the same
+	 * transaction to do unnecessary work. So update last_reflink_trans
+	 * to the last_trans value (we have to be pessimistic and assume a
+	 * reflink happened).
+	 *
+	 * The ->last_trans is protected by the inode's spinlock and we can
+	 * have a concurrent ordered extent completion update it. Also set
+	 * last_reflink_trans to ->last_trans only if the former is less than
+	 * the later, because we can be called in a context where
+	 * last_reflink_trans was set to the current transaction generation
+	 * while ->last_trans was not yet updated in the current transaction,
+	 * and therefore has a lower value.
+	 */
+	spin_lock(&inode->lock);
+	if (inode->last_reflink_trans < inode->last_trans)
+		inode->last_reflink_trans = inode->last_trans;
+	spin_unlock(&inode->lock);
+}
+
+static inline bool btrfs_inode_in_log(struct btrfs_inode *inode, u64 generation)
+{
+	bool ret = false;
+
+	spin_lock(&inode->lock);
+	if (inode->logged_trans == generation &&
+	    inode->last_sub_trans <= inode->last_log_commit &&
+	    inode->last_sub_trans <= inode->root->last_log_commit)
+		ret = true;
+	spin_unlock(&inode->lock);
+	return ret;
+}
+
+/*
+ * Check if the inode has flags compatible with compression
+ */
+static inline bool btrfs_inode_can_compress(const struct btrfs_inode *inode)
+{
+	if (inode->flags & BTRFS_INODE_NODATACOW ||
+	    inode->flags & BTRFS_INODE_NODATASUM)
+		return false;
+	return true;
+}
+
+/* Array of bytes with variable length, hexadecimal format 0x1234 */
+#define CSUM_FMT				"0x%*phN"
+#define CSUM_FMT_VALUE(size, bytes)		size, bytes
+
+int btrfs_check_sector_csum(struct btrfs_fs_info *fs_info, struct page *page,
+			    u32 pgoff, u8 *csum, const u8 * const csum_expected);
+bool btrfs_data_csum_ok(struct btrfs_bio *bbio, struct btrfs_device *dev,
+			u32 bio_offset, struct bio_vec *bv);
+noinline int can_nocow_extent(struct inode *inode, u64 offset, u64 *len,
+			      u64 *orig_start, u64 *orig_block_len,
+			      u64 *ram_bytes, bool nowait, bool strict);
+
+void __btrfs_del_delalloc_inode(struct btrfs_root *root, struct btrfs_inode *inode);
+struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry);
+int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index);
+int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
+		       struct btrfs_inode *dir, struct btrfs_inode *inode,
+		       const struct fscrypt_str *name);
+int btrfs_add_link(struct btrfs_trans_handle *trans,
+		   struct btrfs_inode *parent_inode, struct btrfs_inode *inode,
+		   const struct fscrypt_str *name, int add_backref, u64 index);
+int btrfs_delete_subvolume(struct btrfs_inode *dir, struct dentry *dentry);
+int btrfs_truncate_block(struct btrfs_inode *inode, loff_t from, loff_t len,
+			 int front);
+
+int btrfs_start_delalloc_snapshot(struct btrfs_root *root, bool in_reclaim_context);
+int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, long nr,
+			       bool in_reclaim_context);
+int btrfs_set_extent_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
+			      unsigned int extra_bits,
+			      struct extent_state **cached_state);
+
+struct btrfs_new_inode_args {
+	/* Input */
+	struct inode *dir;
+	struct dentry *dentry;
+	struct inode *inode;
+	bool orphan;
+	bool subvol;
+
+	/* Output from btrfs_new_inode_prepare(), input to btrfs_create_new_inode(). */
+	struct posix_acl *default_acl;
+	struct posix_acl *acl;
+	struct fscrypt_name fname;
+};
+
+int btrfs_new_inode_prepare(struct btrfs_new_inode_args *args,
+			    unsigned int *trans_num_items);
+int btrfs_create_new_inode(struct btrfs_trans_handle *trans,
+			   struct btrfs_new_inode_args *args);
+void btrfs_new_inode_args_destroy(struct btrfs_new_inode_args *args);
+struct inode *btrfs_new_subvol_inode(struct mnt_idmap *idmap,
+				     struct inode *dir);
+ void btrfs_set_delalloc_extent(struct btrfs_inode *inode, struct extent_state *state,
+			        u32 bits);
+void btrfs_clear_delalloc_extent(struct btrfs_inode *inode,
+				 struct extent_state *state, u32 bits);
+void btrfs_merge_delalloc_extent(struct btrfs_inode *inode, struct extent_state *new,
+				 struct extent_state *other);
+void btrfs_split_delalloc_extent(struct btrfs_inode *inode,
+				 struct extent_state *orig, u64 split);
+void btrfs_set_range_writeback(struct btrfs_inode *inode, u64 start, u64 end);
+vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf);
+void btrfs_evict_inode(struct inode *inode);
+struct inode *btrfs_alloc_inode(struct super_block *sb);
+void btrfs_destroy_inode(struct inode *inode);
+void btrfs_free_inode(struct inode *inode);
+int btrfs_drop_inode(struct inode *inode);
+int __init btrfs_init_cachep(void);
+void __cold btrfs_destroy_cachep(void);
+struct inode *btrfs_iget_path(struct super_block *s, u64 ino,
+			      struct btrfs_root *root, struct btrfs_path *path);
+struct inode *btrfs_iget(struct super_block *s, u64 ino, struct btrfs_root *root);
+struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
+				    struct page *page, size_t pg_offset,
+				    u64 start, u64 end);
+int btrfs_update_inode(struct btrfs_trans_handle *trans,
+		       struct btrfs_root *root, struct btrfs_inode *inode);
+int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
+				struct btrfs_root *root, struct btrfs_inode *inode);
+int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct btrfs_inode *inode);
+int btrfs_orphan_cleanup(struct btrfs_root *root);
+int btrfs_cont_expand(struct btrfs_inode *inode, loff_t oldsize, loff_t size);
+void btrfs_add_delayed_iput(struct btrfs_inode *inode);
+void btrfs_run_delayed_iputs(struct btrfs_fs_info *fs_info);
+int btrfs_wait_on_delayed_iputs(struct btrfs_fs_info *fs_info);
+int btrfs_prealloc_file_range(struct inode *inode, int mode,
+			      u64 start, u64 num_bytes, u64 min_size,
+			      loff_t actual_len, u64 *alloc_hint);
+int btrfs_prealloc_file_range_trans(struct inode *inode,
+				    struct btrfs_trans_handle *trans, int mode,
+				    u64 start, u64 num_bytes, u64 min_size,
+				    loff_t actual_len, u64 *alloc_hint);
+int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct page *locked_page,
+			     u64 start, u64 end, struct writeback_control *wbc);
+int btrfs_writepage_cow_fixup(struct page *page);
+int btrfs_encoded_io_compression_from_extent(struct btrfs_fs_info *fs_info,
+					     int compress_type);
+int btrfs_encoded_read_regular_fill_pages(struct btrfs_inode *inode,
+					  u64 file_offset, u64 disk_bytenr,
+					  u64 disk_io_size,
+					  struct page **pages);
+ssize_t btrfs_encoded_read(struct kiocb *iocb, struct iov_iter *iter,
+			   struct btrfs_ioctl_encoded_io_args *encoded);
+ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from,
+			       const struct btrfs_ioctl_encoded_io_args *encoded);
+
+ssize_t btrfs_dio_read(struct kiocb *iocb, struct iov_iter *iter,
+		       size_t done_before);
+struct iomap_dio *btrfs_dio_write(struct kiocb *iocb, struct iov_iter *iter,
+				  size_t done_before);
+
+extern const struct dentry_operations btrfs_dentry_operations;
+
+/* Inode locking type flags, by default the exclusive lock is taken. */
+enum btrfs_ilock_type {
+	ENUM_BIT(BTRFS_ILOCK_SHARED),
+	ENUM_BIT(BTRFS_ILOCK_TRY),
+	ENUM_BIT(BTRFS_ILOCK_MMAP),
+};
+
+int btrfs_inode_lock(struct btrfs_inode *inode, unsigned int ilock_flags);
+void btrfs_inode_unlock(struct btrfs_inode *inode, unsigned int ilock_flags);
+void btrfs_update_inode_bytes(struct btrfs_inode *inode, const u64 add_bytes,
+			      const u64 del_bytes);
+void btrfs_assert_inode_range_clean(struct btrfs_inode *inode, u64 start, u64 end);
+
+#endif