xref: /linux/fs/btrfs/raid-stripe-tree.c (revision bf52ca5912c07664276c7b94db820fa2d638b681)
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 		start += key.offset;
70 		length -= key.offset;
71 		if (length == 0)
72 			break;
73 
74 		btrfs_release_path(path);
75 	}
76 
77 	btrfs_free_path(path);
78 	return ret;
79 }
80 
81 static int update_raid_extent_item(struct btrfs_trans_handle *trans,
82 				   struct btrfs_key *key,
83 				   struct btrfs_stripe_extent *stripe_extent,
84 				   const size_t item_size)
85 {
86 	struct btrfs_path *path;
87 	struct extent_buffer *leaf;
88 	int ret;
89 	int slot;
90 
91 	path = btrfs_alloc_path();
92 	if (!path)
93 		return -ENOMEM;
94 
95 	ret = btrfs_search_slot(trans, trans->fs_info->stripe_root, key, path,
96 				0, 1);
97 	if (ret)
98 		return (ret == 1 ? ret : -EINVAL);
99 
100 	leaf = path->nodes[0];
101 	slot = path->slots[0];
102 
103 	write_extent_buffer(leaf, stripe_extent, btrfs_item_ptr_offset(leaf, slot),
104 			    item_size);
105 	btrfs_mark_buffer_dirty(trans, leaf);
106 	btrfs_free_path(path);
107 
108 	return ret;
109 }
110 
111 static int btrfs_insert_one_raid_extent(struct btrfs_trans_handle *trans,
112 					struct btrfs_io_context *bioc)
113 {
114 	struct btrfs_fs_info *fs_info = trans->fs_info;
115 	struct btrfs_key stripe_key;
116 	struct btrfs_root *stripe_root = fs_info->stripe_root;
117 	const int num_stripes = btrfs_bg_type_to_factor(bioc->map_type);
118 	struct btrfs_stripe_extent *stripe_extent;
119 	const size_t item_size = struct_size(stripe_extent, strides, num_stripes);
120 	int ret;
121 
122 	stripe_extent = kzalloc(item_size, GFP_NOFS);
123 	if (!stripe_extent) {
124 		btrfs_abort_transaction(trans, -ENOMEM);
125 		btrfs_end_transaction(trans);
126 		return -ENOMEM;
127 	}
128 
129 	trace_btrfs_insert_one_raid_extent(fs_info, bioc->logical, bioc->size,
130 					   num_stripes);
131 	for (int i = 0; i < num_stripes; i++) {
132 		u64 devid = bioc->stripes[i].dev->devid;
133 		u64 physical = bioc->stripes[i].physical;
134 		u64 length = bioc->stripes[i].length;
135 		struct btrfs_raid_stride *raid_stride = &stripe_extent->strides[i];
136 
137 		if (length == 0)
138 			length = bioc->size;
139 
140 		btrfs_set_stack_raid_stride_devid(raid_stride, devid);
141 		btrfs_set_stack_raid_stride_physical(raid_stride, physical);
142 	}
143 
144 	stripe_key.objectid = bioc->logical;
145 	stripe_key.type = BTRFS_RAID_STRIPE_KEY;
146 	stripe_key.offset = bioc->size;
147 
148 	ret = btrfs_insert_item(trans, stripe_root, &stripe_key, stripe_extent,
149 				item_size);
150 	if (ret == -EEXIST)
151 		ret = update_raid_extent_item(trans, &stripe_key, stripe_extent,
152 					      item_size);
153 	if (ret)
154 		btrfs_abort_transaction(trans, ret);
155 
156 	kfree(stripe_extent);
157 
158 	return ret;
159 }
160 
161 int btrfs_insert_raid_extent(struct btrfs_trans_handle *trans,
162 			     struct btrfs_ordered_extent *ordered_extent)
163 {
164 	struct btrfs_io_context *bioc;
165 	int ret;
166 
167 	if (!btrfs_fs_incompat(trans->fs_info, RAID_STRIPE_TREE))
168 		return 0;
169 
170 	list_for_each_entry(bioc, &ordered_extent->bioc_list, rst_ordered_entry) {
171 		ret = btrfs_insert_one_raid_extent(trans, bioc);
172 		if (ret)
173 			return ret;
174 	}
175 
176 	while (!list_empty(&ordered_extent->bioc_list)) {
177 		bioc = list_first_entry(&ordered_extent->bioc_list,
178 					typeof(*bioc), rst_ordered_entry);
179 		list_del(&bioc->rst_ordered_entry);
180 		btrfs_put_bioc(bioc);
181 	}
182 
183 	return 0;
184 }
185 
186 int btrfs_get_raid_extent_offset(struct btrfs_fs_info *fs_info,
187 				 u64 logical, u64 *length, u64 map_type,
188 				 u32 stripe_index, struct btrfs_io_stripe *stripe)
189 {
190 	struct btrfs_root *stripe_root = fs_info->stripe_root;
191 	struct btrfs_stripe_extent *stripe_extent;
192 	struct btrfs_key stripe_key;
193 	struct btrfs_key found_key;
194 	struct btrfs_path *path;
195 	struct extent_buffer *leaf;
196 	const u64 end = logical + *length;
197 	int num_stripes;
198 	u64 offset;
199 	u64 found_logical;
200 	u64 found_length;
201 	u64 found_end;
202 	int slot;
203 	int ret;
204 
205 	stripe_key.objectid = logical;
206 	stripe_key.type = BTRFS_RAID_STRIPE_KEY;
207 	stripe_key.offset = 0;
208 
209 	path = btrfs_alloc_path();
210 	if (!path)
211 		return -ENOMEM;
212 
213 	if (stripe->rst_search_commit_root) {
214 		path->skip_locking = 1;
215 		path->search_commit_root = 1;
216 	}
217 
218 	ret = btrfs_search_slot(NULL, stripe_root, &stripe_key, path, 0, 0);
219 	if (ret < 0)
220 		goto free_path;
221 	if (ret) {
222 		if (path->slots[0] != 0)
223 			path->slots[0]--;
224 	}
225 
226 	while (1) {
227 		leaf = path->nodes[0];
228 		slot = path->slots[0];
229 
230 		btrfs_item_key_to_cpu(leaf, &found_key, slot);
231 		found_logical = found_key.objectid;
232 		found_length = found_key.offset;
233 		found_end = found_logical + found_length;
234 
235 		if (found_logical > end) {
236 			ret = -ENOENT;
237 			goto out;
238 		}
239 
240 		if (in_range(logical, found_logical, found_length))
241 			break;
242 
243 		ret = btrfs_next_item(stripe_root, path);
244 		if (ret)
245 			goto out;
246 	}
247 
248 	offset = logical - found_logical;
249 
250 	/*
251 	 * If we have a logically contiguous, but physically non-continuous
252 	 * range, we need to split the bio. Record the length after which we
253 	 * must split the bio.
254 	 */
255 	if (end > found_end)
256 		*length -= end - found_end;
257 
258 	num_stripes = btrfs_num_raid_stripes(btrfs_item_size(leaf, slot));
259 	stripe_extent = btrfs_item_ptr(leaf, slot, struct btrfs_stripe_extent);
260 
261 	for (int i = 0; i < num_stripes; i++) {
262 		struct btrfs_raid_stride *stride = &stripe_extent->strides[i];
263 		u64 devid = btrfs_raid_stride_devid(leaf, stride);
264 		u64 physical = btrfs_raid_stride_physical(leaf, stride);
265 
266 		if (devid != stripe->dev->devid)
267 			continue;
268 
269 		if ((map_type & BTRFS_BLOCK_GROUP_DUP) && stripe_index != i)
270 			continue;
271 
272 		stripe->physical = physical + offset;
273 
274 		trace_btrfs_get_raid_extent_offset(fs_info, logical, *length,
275 						   stripe->physical, devid);
276 
277 		ret = 0;
278 		goto free_path;
279 	}
280 
281 	/* If we're here, we haven't found the requested devid in the stripe. */
282 	ret = -ENOENT;
283 out:
284 	if (ret > 0)
285 		ret = -ENOENT;
286 	if (ret && ret != -EIO && !stripe->rst_search_commit_root) {
287 		btrfs_debug(fs_info,
288 		"cannot find raid-stripe for logical [%llu, %llu] devid %llu, profile %s",
289 			  logical, logical + *length, stripe->dev->devid,
290 			  btrfs_bg_type_to_raid_name(map_type));
291 	}
292 free_path:
293 	btrfs_free_path(path);
294 
295 	return ret;
296 }
297