diff options
Diffstat (limited to 'fs/btrfs/misc.h')
| -rw-r--r-- | fs/btrfs/misc.h | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/fs/btrfs/misc.h b/fs/btrfs/misc.h new file mode 100644 index 000000000000..12c5a9d6564f --- /dev/null +++ b/fs/btrfs/misc.h @@ -0,0 +1,219 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef BTRFS_MISC_H +#define BTRFS_MISC_H + +#include <linux/types.h> +#include <linux/bitmap.h> +#include <linux/sched.h> +#include <linux/wait.h> +#include <linux/mm.h> +#include <linux/pagemap.h> +#include <linux/math64.h> +#include <linux/rbtree.h> +#include <linux/bio.h> + +/* + * Convenience macros to define a pointer with the __free(kfree) and + * __free(kvfree) cleanup attributes and initialized to NULL. + */ +#define AUTO_KFREE(name) *name __free(kfree) = NULL +#define AUTO_KVFREE(name) *name __free(kvfree) = NULL + +/* + * Enumerate bits using enum autoincrement. Define the @name as the n-th bit. + */ +#define ENUM_BIT(name) \ + __ ## name ## _BIT, \ + name = (1U << __ ## name ## _BIT), \ + __ ## name ## _SEQ = __ ## name ## _BIT + +static inline phys_addr_t bio_iter_phys(struct bio *bio, struct bvec_iter *iter) +{ + struct bio_vec bv = bio_iter_iovec(bio, *iter); + + return bvec_phys(&bv); +} + +/* + * Iterate bio using btrfs block size. + * + * This will handle large folio and highmem. + * + * @paddr: Physical memory address of each iteration + * @bio: The bio to iterate + * @iter: The bvec_iter (pointer) to use. + * @blocksize: The blocksize to iterate. + * + * This requires all folios in the bio to cover at least one block. + */ +#define btrfs_bio_for_each_block(paddr, bio, iter, blocksize) \ + for (; (iter)->bi_size && \ + (paddr = bio_iter_phys((bio), (iter)), 1); \ + bio_advance_iter_single((bio), (iter), (blocksize))) + +/* Initialize a bvec_iter to the size of the specified bio. */ +static inline struct bvec_iter init_bvec_iter_for_bio(struct bio *bio) +{ + struct bio_vec *bvec; + u32 bio_size = 0; + int i; + + bio_for_each_bvec_all(bvec, bio, i) + bio_size += bvec->bv_len; + + return (struct bvec_iter) { + .bi_sector = 0, + .bi_size = bio_size, + .bi_idx = 0, + .bi_bvec_done = 0, + }; +} + +#define btrfs_bio_for_each_block_all(paddr, bio, blocksize) \ + for (struct bvec_iter iter = init_bvec_iter_for_bio(bio); \ + (iter).bi_size && \ + (paddr = bio_iter_phys((bio), &(iter)), 1); \ + bio_advance_iter_single((bio), &(iter), (blocksize))) + +static inline void cond_wake_up(struct wait_queue_head *wq) +{ + /* + * This implies a full smp_mb barrier, see comments for + * waitqueue_active why. + */ + if (wq_has_sleeper(wq)) + wake_up(wq); +} + +static inline void cond_wake_up_nomb(struct wait_queue_head *wq) +{ + /* + * Special case for conditional wakeup where the barrier required for + * waitqueue_active is implied by some of the preceding code. Eg. one + * of such atomic operations (atomic_dec_and_return, ...), or a + * unlock/lock sequence, etc. + */ + if (waitqueue_active(wq)) + wake_up(wq); +} + +static inline u64 mult_perc(u64 num, u32 percent) +{ + return div_u64(num * percent, 100); +} +/* Copy of is_power_of_two that is 64bit safe */ +static inline bool is_power_of_two_u64(u64 n) +{ + return n != 0 && (n & (n - 1)) == 0; +} + +static inline bool has_single_bit_set(u64 n) +{ + return is_power_of_two_u64(n); +} + +/* + * Simple bytenr based rb_tree relate structures + * + * Any structure wants to use bytenr as single search index should have their + * structure start with these members. + */ +struct rb_simple_node { + struct rb_node rb_node; + u64 bytenr; +}; + +static inline struct rb_node *rb_simple_search(const struct rb_root *root, u64 bytenr) +{ + struct rb_node *node = root->rb_node; + struct rb_simple_node *entry; + + while (node) { + entry = rb_entry(node, struct rb_simple_node, rb_node); + + if (bytenr < entry->bytenr) + node = node->rb_left; + else if (bytenr > entry->bytenr) + node = node->rb_right; + else + return node; + } + return NULL; +} + +/* + * Search @root from an entry that starts or comes after @bytenr. + * + * @root: the root to search. + * @bytenr: bytenr to search from. + * + * Return the rb_node that start at or after @bytenr. If there is no entry at + * or after @bytner return NULL. + */ +static inline struct rb_node *rb_simple_search_first(const struct rb_root *root, + u64 bytenr) +{ + struct rb_node *node = root->rb_node, *ret = NULL; + struct rb_simple_node *entry, *ret_entry = NULL; + + while (node) { + entry = rb_entry(node, struct rb_simple_node, rb_node); + + if (bytenr < entry->bytenr) { + if (!ret || entry->bytenr < ret_entry->bytenr) { + ret = node; + ret_entry = entry; + } + + node = node->rb_left; + } else if (bytenr > entry->bytenr) { + node = node->rb_right; + } else { + return node; + } + } + + return ret; +} + +static int rb_simple_node_bytenr_cmp(struct rb_node *new, const struct rb_node *existing) +{ + struct rb_simple_node *new_entry = rb_entry(new, struct rb_simple_node, rb_node); + struct rb_simple_node *existing_entry = rb_entry(existing, struct rb_simple_node, rb_node); + + if (new_entry->bytenr < existing_entry->bytenr) + return -1; + else if (new_entry->bytenr > existing_entry->bytenr) + return 1; + + return 0; +} + +static inline struct rb_node *rb_simple_insert(struct rb_root *root, + struct rb_simple_node *simple_node) +{ + return rb_find_add(&simple_node->rb_node, root, rb_simple_node_bytenr_cmp); +} + +static inline bool bitmap_test_range_all_set(const unsigned long *addr, + unsigned long start, + unsigned long nbits) +{ + unsigned long found_zero; + + found_zero = find_next_zero_bit(addr, start + nbits, start); + return (found_zero == start + nbits); +} + +static inline bool bitmap_test_range_all_zero(const unsigned long *addr, + unsigned long start, + unsigned long nbits) +{ + unsigned long found_set; + + found_set = find_next_bit(addr, start + nbits, start); + return (found_set == start + nbits); +} + +#endif |