xref: /linux/fs/btrfs/raid-stripe-tree.c (revision d7b4e3287ca3a7baf66efd9158498e551a9550da)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2023 Western Digital Corporation or its affiliates.
4  */
5 
6 #include <linux/btrfs_tree.h>
7 #include "ctree.h"
8 #include "fs.h"
9 #include "accessors.h"
10 #include "transaction.h"
11 #include "disk-io.h"
12 #include "raid-stripe-tree.h"
13 #include "volumes.h"
14 #include "misc.h"
15 #include "print-tree.h"
16 
17 int btrfs_delete_raid_extent(struct btrfs_trans_handle *trans, u64 start, u64 length)
18 {
19 	struct btrfs_fs_info *fs_info = trans->fs_info;
20 	struct btrfs_root *stripe_root = fs_info->stripe_root;
21 	struct btrfs_path *path;
22 	struct btrfs_key key;
23 	struct extent_buffer *leaf;
24 	u64 found_start;
25 	u64 found_end;
26 	u64 end = start + length;
27 	int slot;
28 	int ret;
29 
30 	if (!stripe_root)
31 		return 0;
32 
33 	path = btrfs_alloc_path();
34 	if (!path)
35 		return -ENOMEM;
36 
37 	while (1) {
38 		key.objectid = start;
39 		key.type = BTRFS_RAID_STRIPE_KEY;
40 		key.offset = length;
41 
42 		ret = btrfs_search_slot(trans, stripe_root, &key, path, -1, 1);
43 		if (ret < 0)
44 			break;
45 		if (ret > 0) {
46 			ret = 0;
47 			if (path->slots[0] == 0)
48 				break;
49 			path->slots[0]--;
50 		}
51 
52 		leaf = path->nodes[0];
53 		slot = path->slots[0];
54 		btrfs_item_key_to_cpu(leaf, &key, slot);
55 		found_start = key.objectid;
56 		found_end = found_start + key.offset;
57 
58 		/* That stripe ends before we start, we're done. */
59 		if (found_end <= start)
60 			break;
61 
62 		trace_btrfs_raid_extent_delete(fs_info, start, end,
63 					       found_start, found_end);
64 
65 		ASSERT(found_start >= start && found_end <= end);
66 		ret = btrfs_del_item(trans, stripe_root, path);
67 		if (ret)
68 			break;
69 
70 		btrfs_release_path(path);
71 	}
72 
73 	btrfs_free_path(path);
74 	return ret;
75 }
76 
77 static int btrfs_insert_one_raid_extent(struct btrfs_trans_handle *trans,
78 					struct btrfs_io_context *bioc)
79 {
80 	struct btrfs_fs_info *fs_info = trans->fs_info;
81 	struct btrfs_key stripe_key;
82 	struct btrfs_root *stripe_root = fs_info->stripe_root;
83 	const int num_stripes = btrfs_bg_type_to_factor(bioc->map_type);
84 	u8 encoding = btrfs_bg_flags_to_raid_index(bioc->map_type);
85 	struct btrfs_stripe_extent *stripe_extent;
86 	const size_t item_size = struct_size(stripe_extent, strides, num_stripes);
87 	int ret;
88 
89 	stripe_extent = kzalloc(item_size, GFP_NOFS);
90 	if (!stripe_extent) {
91 		btrfs_abort_transaction(trans, -ENOMEM);
92 		btrfs_end_transaction(trans);
93 		return -ENOMEM;
94 	}
95 
96 	trace_btrfs_insert_one_raid_extent(fs_info, bioc->logical, bioc->size,
97 					   num_stripes);
98 	btrfs_set_stack_stripe_extent_encoding(stripe_extent, encoding);
99 	for (int i = 0; i < num_stripes; i++) {
100 		u64 devid = bioc->stripes[i].dev->devid;
101 		u64 physical = bioc->stripes[i].physical;
102 		u64 length = bioc->stripes[i].length;
103 		struct btrfs_raid_stride *raid_stride = &stripe_extent->strides[i];
104 
105 		if (length == 0)
106 			length = bioc->size;
107 
108 		btrfs_set_stack_raid_stride_devid(raid_stride, devid);
109 		btrfs_set_stack_raid_stride_physical(raid_stride, physical);
110 	}
111 
112 	stripe_key.objectid = bioc->logical;
113 	stripe_key.type = BTRFS_RAID_STRIPE_KEY;
114 	stripe_key.offset = bioc->size;
115 
116 	ret = btrfs_insert_item(trans, stripe_root, &stripe_key, stripe_extent,
117 				item_size);
118 	if (ret)
119 		btrfs_abort_transaction(trans, ret);
120 
121 	kfree(stripe_extent);
122 
123 	return ret;
124 }
125 
126 int btrfs_insert_raid_extent(struct btrfs_trans_handle *trans,
127 			     struct btrfs_ordered_extent *ordered_extent)
128 {
129 	struct btrfs_io_context *bioc;
130 	int ret;
131 
132 	if (!btrfs_fs_incompat(trans->fs_info, RAID_STRIPE_TREE))
133 		return 0;
134 
135 	list_for_each_entry(bioc, &ordered_extent->bioc_list, rst_ordered_entry) {
136 		ret = btrfs_insert_one_raid_extent(trans, bioc);
137 		if (ret)
138 			return ret;
139 	}
140 
141 	while (!list_empty(&ordered_extent->bioc_list)) {
142 		bioc = list_first_entry(&ordered_extent->bioc_list,
143 					typeof(*bioc), rst_ordered_entry);
144 		list_del(&bioc->rst_ordered_entry);
145 		btrfs_put_bioc(bioc);
146 	}
147 
148 	return 0;
149 }
150 
151 int btrfs_get_raid_extent_offset(struct btrfs_fs_info *fs_info,
152 				 u64 logical, u64 *length, u64 map_type,
153 				 u32 stripe_index, struct btrfs_io_stripe *stripe)
154 {
155 	struct btrfs_root *stripe_root = fs_info->stripe_root;
156 	struct btrfs_stripe_extent *stripe_extent;
157 	struct btrfs_key stripe_key;
158 	struct btrfs_key found_key;
159 	struct btrfs_path *path;
160 	struct extent_buffer *leaf;
161 	const u64 end = logical + *length;
162 	int num_stripes;
163 	u8 encoding;
164 	u64 offset;
165 	u64 found_logical;
166 	u64 found_length;
167 	u64 found_end;
168 	int slot;
169 	int ret;
170 
171 	stripe_key.objectid = logical;
172 	stripe_key.type = BTRFS_RAID_STRIPE_KEY;
173 	stripe_key.offset = 0;
174 
175 	path = btrfs_alloc_path();
176 	if (!path)
177 		return -ENOMEM;
178 
179 	if (stripe->is_scrub) {
180 		path->skip_locking = 1;
181 		path->search_commit_root = 1;
182 	}
183 
184 	ret = btrfs_search_slot(NULL, stripe_root, &stripe_key, path, 0, 0);
185 	if (ret < 0)
186 		goto free_path;
187 	if (ret) {
188 		if (path->slots[0] != 0)
189 			path->slots[0]--;
190 	}
191 
192 	while (1) {
193 		leaf = path->nodes[0];
194 		slot = path->slots[0];
195 
196 		btrfs_item_key_to_cpu(leaf, &found_key, slot);
197 		found_logical = found_key.objectid;
198 		found_length = found_key.offset;
199 		found_end = found_logical + found_length;
200 
201 		if (found_logical > end) {
202 			ret = -ENOENT;
203 			goto out;
204 		}
205 
206 		if (in_range(logical, found_logical, found_length))
207 			break;
208 
209 		ret = btrfs_next_item(stripe_root, path);
210 		if (ret)
211 			goto out;
212 	}
213 
214 	offset = logical - found_logical;
215 
216 	/*
217 	 * If we have a logically contiguous, but physically non-continuous
218 	 * range, we need to split the bio. Record the length after which we
219 	 * must split the bio.
220 	 */
221 	if (end > found_end)
222 		*length -= end - found_end;
223 
224 	num_stripes = btrfs_num_raid_stripes(btrfs_item_size(leaf, slot));
225 	stripe_extent = btrfs_item_ptr(leaf, slot, struct btrfs_stripe_extent);
226 	encoding = btrfs_stripe_extent_encoding(leaf, stripe_extent);
227 
228 	if (encoding != btrfs_bg_flags_to_raid_index(map_type)) {
229 		ret = -EUCLEAN;
230 		btrfs_handle_fs_error(fs_info, ret,
231 				      "on-disk stripe encoding %d doesn't match RAID index %d",
232 				      encoding,
233 				      btrfs_bg_flags_to_raid_index(map_type));
234 		goto out;
235 	}
236 
237 	for (int i = 0; i < num_stripes; i++) {
238 		struct btrfs_raid_stride *stride = &stripe_extent->strides[i];
239 		u64 devid = btrfs_raid_stride_devid(leaf, stride);
240 		u64 physical = btrfs_raid_stride_physical(leaf, stride);
241 
242 		if (devid != stripe->dev->devid)
243 			continue;
244 
245 		if ((map_type & BTRFS_BLOCK_GROUP_DUP) && stripe_index != i)
246 			continue;
247 
248 		stripe->physical = physical + offset;
249 
250 		trace_btrfs_get_raid_extent_offset(fs_info, logical, *length,
251 						   stripe->physical, devid);
252 
253 		ret = 0;
254 		goto free_path;
255 	}
256 
257 	/* If we're here, we haven't found the requested devid in the stripe. */
258 	ret = -ENOENT;
259 out:
260 	if (ret > 0)
261 		ret = -ENOENT;
262 	if (ret && ret != -EIO && !stripe->is_scrub) {
263 		if (IS_ENABLED(CONFIG_BTRFS_DEBUG))
264 			btrfs_print_tree(leaf, 1);
265 		btrfs_err(fs_info,
266 		"cannot find raid-stripe for logical [%llu, %llu] devid %llu, profile %s",
267 			  logical, logical + *length, stripe->dev->devid,
268 			  btrfs_bg_type_to_raid_name(map_type));
269 	}
270 free_path:
271 	btrfs_free_path(path);
272 
273 	return ret;
274 }
275