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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /fs/btrfs/tree-defrag.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fs/btrfs/tree-defrag.c')
-rw-r--r--fs/btrfs/tree-defrag.c471
1 files changed, 471 insertions, 0 deletions
diff --git a/fs/btrfs/tree-defrag.c b/fs/btrfs/tree-defrag.c
new file mode 100644
index 000000000..0520d6d32
--- /dev/null
+++ b/fs/btrfs/tree-defrag.c
@@ -0,0 +1,471 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2007 Oracle. All rights reserved.
+ */
+
+#include <linux/sched.h>
+#include "ctree.h"
+#include "disk-io.h"
+#include "print-tree.h"
+#include "transaction.h"
+#include "locking.h"
+
+static struct kmem_cache *btrfs_inode_defrag_cachep;
+
+/*
+ * When auto defrag is enabled we queue up these defrag structs to remember
+ * which inodes need defragging passes.
+ */
+struct inode_defrag {
+ struct rb_node rb_node;
+ /* Inode number */
+ u64 ino;
+ /*
+ * Transid where the defrag was added, we search for extents newer than
+ * this.
+ */
+ u64 transid;
+
+ /* Root objectid */
+ u64 root;
+
+ /*
+ * The extent size threshold for autodefrag.
+ *
+ * This value is different for compressed/non-compressed extents, thus
+ * needs to be passed from higher layer.
+ * (aka, inode_should_defrag())
+ */
+ u32 extent_thresh;
+};
+
+static int __compare_inode_defrag(struct inode_defrag *defrag1,
+ struct inode_defrag *defrag2)
+{
+ if (defrag1->root > defrag2->root)
+ return 1;
+ else if (defrag1->root < defrag2->root)
+ return -1;
+ else if (defrag1->ino > defrag2->ino)
+ return 1;
+ else if (defrag1->ino < defrag2->ino)
+ return -1;
+ else
+ return 0;
+}
+
+/*
+ * Pop a record for an inode into the defrag tree. The lock must be held
+ * already.
+ *
+ * If you're inserting a record for an older transid than an existing record,
+ * the transid already in the tree is lowered.
+ *
+ * If an existing record is found the defrag item you pass in is freed.
+ */
+static int __btrfs_add_inode_defrag(struct btrfs_inode *inode,
+ struct inode_defrag *defrag)
+{
+ struct btrfs_fs_info *fs_info = inode->root->fs_info;
+ struct inode_defrag *entry;
+ struct rb_node **p;
+ struct rb_node *parent = NULL;
+ int ret;
+
+ p = &fs_info->defrag_inodes.rb_node;
+ while (*p) {
+ parent = *p;
+ entry = rb_entry(parent, struct inode_defrag, rb_node);
+
+ ret = __compare_inode_defrag(defrag, entry);
+ if (ret < 0)
+ p = &parent->rb_left;
+ else if (ret > 0)
+ p = &parent->rb_right;
+ else {
+ /*
+ * If we're reinserting an entry for an old defrag run,
+ * make sure to lower the transid of our existing
+ * record.
+ */
+ if (defrag->transid < entry->transid)
+ entry->transid = defrag->transid;
+ entry->extent_thresh = min(defrag->extent_thresh,
+ entry->extent_thresh);
+ return -EEXIST;
+ }
+ }
+ set_bit(BTRFS_INODE_IN_DEFRAG, &inode->runtime_flags);
+ rb_link_node(&defrag->rb_node, parent, p);
+ rb_insert_color(&defrag->rb_node, &fs_info->defrag_inodes);
+ return 0;
+}
+
+static inline int __need_auto_defrag(struct btrfs_fs_info *fs_info)
+{
+ if (!btrfs_test_opt(fs_info, AUTO_DEFRAG))
+ return 0;
+
+ if (btrfs_fs_closing(fs_info))
+ return 0;
+
+ return 1;
+}
+
+/*
+ * Insert a defrag record for this inode if auto defrag is enabled.
+ */
+int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
+ struct btrfs_inode *inode, u32 extent_thresh)
+{
+ struct btrfs_root *root = inode->root;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct inode_defrag *defrag;
+ u64 transid;
+ int ret;
+
+ if (!__need_auto_defrag(fs_info))
+ return 0;
+
+ if (test_bit(BTRFS_INODE_IN_DEFRAG, &inode->runtime_flags))
+ return 0;
+
+ if (trans)
+ transid = trans->transid;
+ else
+ transid = inode->root->last_trans;
+
+ defrag = kmem_cache_zalloc(btrfs_inode_defrag_cachep, GFP_NOFS);
+ if (!defrag)
+ return -ENOMEM;
+
+ defrag->ino = btrfs_ino(inode);
+ defrag->transid = transid;
+ defrag->root = root->root_key.objectid;
+ defrag->extent_thresh = extent_thresh;
+
+ spin_lock(&fs_info->defrag_inodes_lock);
+ if (!test_bit(BTRFS_INODE_IN_DEFRAG, &inode->runtime_flags)) {
+ /*
+ * If we set IN_DEFRAG flag and evict the inode from memory,
+ * and then re-read this inode, this new inode doesn't have
+ * IN_DEFRAG flag. At the case, we may find the existed defrag.
+ */
+ ret = __btrfs_add_inode_defrag(inode, defrag);
+ if (ret)
+ kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
+ } else {
+ kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
+ }
+ spin_unlock(&fs_info->defrag_inodes_lock);
+ return 0;
+}
+
+/*
+ * Pick the defragable inode that we want, if it doesn't exist, we will get the
+ * next one.
+ */
+static struct inode_defrag *btrfs_pick_defrag_inode(
+ struct btrfs_fs_info *fs_info, u64 root, u64 ino)
+{
+ struct inode_defrag *entry = NULL;
+ struct inode_defrag tmp;
+ struct rb_node *p;
+ struct rb_node *parent = NULL;
+ int ret;
+
+ tmp.ino = ino;
+ tmp.root = root;
+
+ spin_lock(&fs_info->defrag_inodes_lock);
+ p = fs_info->defrag_inodes.rb_node;
+ while (p) {
+ parent = p;
+ entry = rb_entry(parent, struct inode_defrag, rb_node);
+
+ ret = __compare_inode_defrag(&tmp, entry);
+ if (ret < 0)
+ p = parent->rb_left;
+ else if (ret > 0)
+ p = parent->rb_right;
+ else
+ goto out;
+ }
+
+ if (parent && __compare_inode_defrag(&tmp, entry) > 0) {
+ parent = rb_next(parent);
+ if (parent)
+ entry = rb_entry(parent, struct inode_defrag, rb_node);
+ else
+ entry = NULL;
+ }
+out:
+ if (entry)
+ rb_erase(parent, &fs_info->defrag_inodes);
+ spin_unlock(&fs_info->defrag_inodes_lock);
+ return entry;
+}
+
+void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info)
+{
+ struct inode_defrag *defrag;
+ struct rb_node *node;
+
+ spin_lock(&fs_info->defrag_inodes_lock);
+ node = rb_first(&fs_info->defrag_inodes);
+ while (node) {
+ rb_erase(node, &fs_info->defrag_inodes);
+ defrag = rb_entry(node, struct inode_defrag, rb_node);
+ kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
+
+ cond_resched_lock(&fs_info->defrag_inodes_lock);
+
+ node = rb_first(&fs_info->defrag_inodes);
+ }
+ spin_unlock(&fs_info->defrag_inodes_lock);
+}
+
+#define BTRFS_DEFRAG_BATCH 1024
+
+static int __btrfs_run_defrag_inode(struct btrfs_fs_info *fs_info,
+ struct inode_defrag *defrag)
+{
+ struct btrfs_root *inode_root;
+ struct inode *inode;
+ struct btrfs_ioctl_defrag_range_args range;
+ int ret = 0;
+ u64 cur = 0;
+
+again:
+ if (test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state))
+ goto cleanup;
+ if (!__need_auto_defrag(fs_info))
+ goto cleanup;
+
+ /* Get the inode */
+ inode_root = btrfs_get_fs_root(fs_info, defrag->root, true);
+ if (IS_ERR(inode_root)) {
+ ret = PTR_ERR(inode_root);
+ goto cleanup;
+ }
+
+ inode = btrfs_iget(fs_info->sb, defrag->ino, inode_root);
+ btrfs_put_root(inode_root);
+ if (IS_ERR(inode)) {
+ ret = PTR_ERR(inode);
+ goto cleanup;
+ }
+
+ if (cur >= i_size_read(inode)) {
+ iput(inode);
+ goto cleanup;
+ }
+
+ /* Do a chunk of defrag */
+ clear_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags);
+ memset(&range, 0, sizeof(range));
+ range.len = (u64)-1;
+ range.start = cur;
+ range.extent_thresh = defrag->extent_thresh;
+
+ sb_start_write(fs_info->sb);
+ ret = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
+ BTRFS_DEFRAG_BATCH);
+ sb_end_write(fs_info->sb);
+ iput(inode);
+
+ if (ret < 0)
+ goto cleanup;
+
+ cur = max(cur + fs_info->sectorsize, range.start);
+ goto again;
+
+cleanup:
+ kmem_cache_free(btrfs_inode_defrag_cachep, defrag);
+ return ret;
+}
+
+/*
+ * Run through the list of inodes in the FS that need defragging.
+ */
+int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
+{
+ struct inode_defrag *defrag;
+ u64 first_ino = 0;
+ u64 root_objectid = 0;
+
+ atomic_inc(&fs_info->defrag_running);
+ while (1) {
+ /* Pause the auto defragger. */
+ if (test_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state))
+ break;
+
+ if (!__need_auto_defrag(fs_info))
+ break;
+
+ /* find an inode to defrag */
+ defrag = btrfs_pick_defrag_inode(fs_info, root_objectid, first_ino);
+ if (!defrag) {
+ if (root_objectid || first_ino) {
+ root_objectid = 0;
+ first_ino = 0;
+ continue;
+ } else {
+ break;
+ }
+ }
+
+ first_ino = defrag->ino + 1;
+ root_objectid = defrag->root;
+
+ __btrfs_run_defrag_inode(fs_info, defrag);
+ }
+ atomic_dec(&fs_info->defrag_running);
+
+ /*
+ * During unmount, we use the transaction_wait queue to wait for the
+ * defragger to stop.
+ */
+ wake_up(&fs_info->transaction_wait);
+ return 0;
+}
+
+/*
+ * Defrag all the leaves in a given btree.
+ * Read all the leaves and try to get key order to
+ * better reflect disk order
+ */
+
+int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ struct btrfs_path *path = NULL;
+ struct btrfs_key key;
+ int ret = 0;
+ int wret;
+ int level;
+ int next_key_ret = 0;
+ u64 last_ret = 0;
+
+ if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
+ goto out;
+
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ level = btrfs_header_level(root->node);
+
+ if (level == 0)
+ goto out;
+
+ if (root->defrag_progress.objectid == 0) {
+ struct extent_buffer *root_node;
+ u32 nritems;
+
+ root_node = btrfs_lock_root_node(root);
+ nritems = btrfs_header_nritems(root_node);
+ root->defrag_max.objectid = 0;
+ /* from above we know this is not a leaf */
+ btrfs_node_key_to_cpu(root_node, &root->defrag_max,
+ nritems - 1);
+ btrfs_tree_unlock(root_node);
+ free_extent_buffer(root_node);
+ memset(&key, 0, sizeof(key));
+ } else {
+ memcpy(&key, &root->defrag_progress, sizeof(key));
+ }
+
+ path->keep_locks = 1;
+
+ ret = btrfs_search_forward(root, &key, path, BTRFS_OLDEST_GENERATION);
+ if (ret < 0)
+ goto out;
+ if (ret > 0) {
+ ret = 0;
+ goto out;
+ }
+ btrfs_release_path(path);
+ /*
+ * We don't need a lock on a leaf. btrfs_realloc_node() will lock all
+ * leafs from path->nodes[1], so set lowest_level to 1 to avoid later
+ * a deadlock (attempting to write lock an already write locked leaf).
+ */
+ path->lowest_level = 1;
+ wret = btrfs_search_slot(trans, root, &key, path, 0, 1);
+
+ if (wret < 0) {
+ ret = wret;
+ goto out;
+ }
+ if (!path->nodes[1]) {
+ ret = 0;
+ goto out;
+ }
+ /*
+ * The node at level 1 must always be locked when our path has
+ * keep_locks set and lowest_level is 1, regardless of the value of
+ * path->slots[1].
+ */
+ BUG_ON(path->locks[1] == 0);
+ ret = btrfs_realloc_node(trans, root,
+ path->nodes[1], 0,
+ &last_ret,
+ &root->defrag_progress);
+ if (ret) {
+ WARN_ON(ret == -EAGAIN);
+ goto out;
+ }
+ /*
+ * Now that we reallocated the node we can find the next key. Note that
+ * btrfs_find_next_key() can release our path and do another search
+ * without COWing, this is because even with path->keep_locks = 1,
+ * btrfs_search_slot() / ctree.c:unlock_up() does not keeps a lock on a
+ * node when path->slots[node_level - 1] does not point to the last
+ * item or a slot beyond the last item (ctree.c:unlock_up()). Therefore
+ * we search for the next key after reallocating our node.
+ */
+ path->slots[1] = btrfs_header_nritems(path->nodes[1]);
+ next_key_ret = btrfs_find_next_key(root, path, &key, 1,
+ BTRFS_OLDEST_GENERATION);
+ if (next_key_ret == 0) {
+ memcpy(&root->defrag_progress, &key, sizeof(key));
+ ret = -EAGAIN;
+ }
+out:
+ btrfs_free_path(path);
+ if (ret == -EAGAIN) {
+ if (root->defrag_max.objectid > root->defrag_progress.objectid)
+ goto done;
+ if (root->defrag_max.type > root->defrag_progress.type)
+ goto done;
+ if (root->defrag_max.offset > root->defrag_progress.offset)
+ goto done;
+ ret = 0;
+ }
+done:
+ if (ret != -EAGAIN)
+ memset(&root->defrag_progress, 0,
+ sizeof(root->defrag_progress));
+
+ return ret;
+}
+
+void __cold btrfs_auto_defrag_exit(void)
+{
+ kmem_cache_destroy(btrfs_inode_defrag_cachep);
+}
+
+int __init btrfs_auto_defrag_init(void)
+{
+ btrfs_inode_defrag_cachep = kmem_cache_create("btrfs_inode_defrag",
+ sizeof(struct inode_defrag), 0,
+ SLAB_MEM_SPREAD,
+ NULL);
+ if (!btrfs_inode_defrag_cachep)
+ return -ENOMEM;
+
+ return 0;
+}