xref: /linux/fs/btrfs/raid-stripe-tree.c (revision 45d8b572fac3aa8b49d53c946b3685eaf78a2824)
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 "print-tree.h"
15 
16 int btrfs_delete_raid_extent(struct btrfs_trans_handle *trans, u64 start, u64 length)
17 {
18 	struct btrfs_fs_info *fs_info = trans->fs_info;
19 	struct btrfs_root *stripe_root = fs_info->stripe_root;
20 	struct btrfs_path *path;
21 	struct btrfs_key key;
22 	struct extent_buffer *leaf;
23 	u64 found_start;
24 	u64 found_end;
25 	u64 end = start + length;
26 	int slot;
27 	int ret;
28 
29 	if (!stripe_root)
30 		return 0;
31 
32 	path = btrfs_alloc_path();
33 	if (!path)
34 		return -ENOMEM;
35 
36 	while (1) {
37 		key.objectid = start;
38 		key.type = BTRFS_RAID_STRIPE_KEY;
39 		key.offset = length;
40 
41 		ret = btrfs_search_slot(trans, stripe_root, &key, path, -1, 1);
42 		if (ret < 0)
43 			break;
44 		if (ret > 0) {
45 			ret = 0;
46 			if (path->slots[0] == 0)
47 				break;
48 			path->slots[0]--;
49 		}
50 
51 		leaf = path->nodes[0];
52 		slot = path->slots[0];
53 		btrfs_item_key_to_cpu(leaf, &key, slot);
54 		found_start = key.objectid;
55 		found_end = found_start + key.offset;
56 
57 		/* That stripe ends before we start, we're done. */
58 		if (found_end <= start)
59 			break;
60 
61 		trace_btrfs_raid_extent_delete(fs_info, start, end,
62 					       found_start, found_end);
63 
64 		ASSERT(found_start >= start && found_end <= end);
65 		ret = btrfs_del_item(trans, stripe_root, path);
66 		if (ret)
67 			break;
68 
69 		btrfs_release_path(path);
70 	}
71 
72 	btrfs_free_path(path);
73 	return ret;
74 }
75 
76 static int btrfs_insert_one_raid_extent(struct btrfs_trans_handle *trans,
77 					struct btrfs_io_context *bioc)
78 {
79 	struct btrfs_fs_info *fs_info = trans->fs_info;
80 	struct btrfs_key stripe_key;
81 	struct btrfs_root *stripe_root = fs_info->stripe_root;
82 	const int num_stripes = btrfs_bg_type_to_factor(bioc->map_type);
83 	u8 encoding = btrfs_bg_flags_to_raid_index(bioc->map_type);
84 	struct btrfs_stripe_extent *stripe_extent;
85 	const size_t item_size = struct_size(stripe_extent, strides, num_stripes);
86 	int ret;
87 
88 	stripe_extent = kzalloc(item_size, GFP_NOFS);
89 	if (!stripe_extent) {
90 		btrfs_abort_transaction(trans, -ENOMEM);
91 		btrfs_end_transaction(trans);
92 		return -ENOMEM;
93 	}
94 
95 	trace_btrfs_insert_one_raid_extent(fs_info, bioc->logical, bioc->size,
96 					   num_stripes);
97 	btrfs_set_stack_stripe_extent_encoding(stripe_extent, encoding);
98 	for (int i = 0; i < num_stripes; i++) {
99 		u64 devid = bioc->stripes[i].dev->devid;
100 		u64 physical = bioc->stripes[i].physical;
101 		u64 length = bioc->stripes[i].length;
102 		struct btrfs_raid_stride *raid_stride = &stripe_extent->strides[i];
103 
104 		if (length == 0)
105 			length = bioc->size;
106 
107 		btrfs_set_stack_raid_stride_devid(raid_stride, devid);
108 		btrfs_set_stack_raid_stride_physical(raid_stride, physical);
109 	}
110 
111 	stripe_key.objectid = bioc->logical;
112 	stripe_key.type = BTRFS_RAID_STRIPE_KEY;
113 	stripe_key.offset = bioc->size;
114 
115 	ret = btrfs_insert_item(trans, stripe_root, &stripe_key, stripe_extent,
116 				item_size);
117 	if (ret)
118 		btrfs_abort_transaction(trans, ret);
119 
120 	kfree(stripe_extent);
121 
122 	return ret;
123 }
124 
125 int btrfs_insert_raid_extent(struct btrfs_trans_handle *trans,
126 			     struct btrfs_ordered_extent *ordered_extent)
127 {
128 	struct btrfs_io_context *bioc;
129 	int ret;
130 
131 	if (!btrfs_fs_incompat(trans->fs_info, RAID_STRIPE_TREE))
132 		return 0;
133 
134 	list_for_each_entry(bioc, &ordered_extent->bioc_list, rst_ordered_entry) {
135 		ret = btrfs_insert_one_raid_extent(trans, bioc);
136 		if (ret)
137 			return ret;
138 	}
139 
140 	while (!list_empty(&ordered_extent->bioc_list)) {
141 		bioc = list_first_entry(&ordered_extent->bioc_list,
142 					typeof(*bioc), rst_ordered_entry);
143 		list_del(&bioc->rst_ordered_entry);
144 		btrfs_put_bioc(bioc);
145 	}
146 
147 	return 0;
148 }
149 
150 int btrfs_get_raid_extent_offset(struct btrfs_fs_info *fs_info,
151 				 u64 logical, u64 *length, u64 map_type,
152 				 u32 stripe_index, struct btrfs_io_stripe *stripe)
153 {
154 	struct btrfs_root *stripe_root = fs_info->stripe_root;
155 	struct btrfs_stripe_extent *stripe_extent;
156 	struct btrfs_key stripe_key;
157 	struct btrfs_key found_key;
158 	struct btrfs_path *path;
159 	struct extent_buffer *leaf;
160 	const u64 end = logical + *length;
161 	int num_stripes;
162 	u8 encoding;
163 	u64 offset;
164 	u64 found_logical;
165 	u64 found_length;
166 	u64 found_end;
167 	int slot;
168 	int ret;
169 
170 	stripe_key.objectid = logical;
171 	stripe_key.type = BTRFS_RAID_STRIPE_KEY;
172 	stripe_key.offset = 0;
173 
174 	path = btrfs_alloc_path();
175 	if (!path)
176 		return -ENOMEM;
177 
178 	if (stripe->is_scrub) {
179 		path->skip_locking = 1;
180 		path->search_commit_root = 1;
181 	}
182 
183 	ret = btrfs_search_slot(NULL, stripe_root, &stripe_key, path, 0, 0);
184 	if (ret < 0)
185 		goto free_path;
186 	if (ret) {
187 		if (path->slots[0] != 0)
188 			path->slots[0]--;
189 	}
190 
191 	while (1) {
192 		leaf = path->nodes[0];
193 		slot = path->slots[0];
194 
195 		btrfs_item_key_to_cpu(leaf, &found_key, slot);
196 		found_logical = found_key.objectid;
197 		found_length = found_key.offset;
198 		found_end = found_logical + found_length;
199 
200 		if (found_logical > end) {
201 			ret = -ENOENT;
202 			goto out;
203 		}
204 
205 		if (in_range(logical, found_logical, found_length))
206 			break;
207 
208 		ret = btrfs_next_item(stripe_root, path);
209 		if (ret)
210 			goto out;
211 	}
212 
213 	offset = logical - found_logical;
214 
215 	/*
216 	 * If we have a logically contiguous, but physically non-continuous
217 	 * range, we need to split the bio. Record the length after which we
218 	 * must split the bio.
219 	 */
220 	if (end > found_end)
221 		*length -= end - found_end;
222 
223 	num_stripes = btrfs_num_raid_stripes(btrfs_item_size(leaf, slot));
224 	stripe_extent = btrfs_item_ptr(leaf, slot, struct btrfs_stripe_extent);
225 	encoding = btrfs_stripe_extent_encoding(leaf, stripe_extent);
226 
227 	if (encoding != btrfs_bg_flags_to_raid_index(map_type)) {
228 		ret = -EUCLEAN;
229 		btrfs_handle_fs_error(fs_info, ret,
230 				      "on-disk stripe encoding %d doesn't match RAID index %d",
231 				      encoding,
232 				      btrfs_bg_flags_to_raid_index(map_type));
233 		goto out;
234 	}
235 
236 	for (int i = 0; i < num_stripes; i++) {
237 		struct btrfs_raid_stride *stride = &stripe_extent->strides[i];
238 		u64 devid = btrfs_raid_stride_devid(leaf, stride);
239 		u64 physical = btrfs_raid_stride_physical(leaf, stride);
240 
241 		if (devid != stripe->dev->devid)
242 			continue;
243 
244 		if ((map_type & BTRFS_BLOCK_GROUP_DUP) && stripe_index != i)
245 			continue;
246 
247 		stripe->physical = physical + offset;
248 
249 		trace_btrfs_get_raid_extent_offset(fs_info, logical, *length,
250 						   stripe->physical, devid);
251 
252 		ret = 0;
253 		goto free_path;
254 	}
255 
256 	/* If we're here, we haven't found the requested devid in the stripe. */
257 	ret = -ENOENT;
258 out:
259 	if (ret > 0)
260 		ret = -ENOENT;
261 	if (ret && ret != -EIO && !stripe->is_scrub) {
262 		if (IS_ENABLED(CONFIG_BTRFS_DEBUG))
263 			btrfs_print_tree(leaf, 1);
264 		btrfs_err(fs_info,
265 		"cannot find raid-stripe for logical [%llu, %llu] devid %llu, profile %s",
266 			  logical, logical + *length, stripe->dev->devid,
267 			  btrfs_bg_type_to_raid_name(map_type));
268 	}
269 free_path:
270 	btrfs_free_path(path);
271 
272 	return ret;
273 }
274