13 #include <linux/bio.h>
14 #include <linux/blkdev.h>
15 #include <linux/completion.h>
17 #include <linux/kthread.h>
19 #include "tools-util.h"
21 static io_context_t aio_ctx;
23 void generic_make_request(struct bio *bio)
26 struct bvec_iter iter;
31 if (bio->bi_opf & REQ_PREFLUSH) {
32 ret = fdatasync(bio->bi_bdev->bd_fd);
34 fprintf(stderr, "fsync error: %m\n");
42 bio_for_each_segment(bv, bio, iter)
45 iov = alloca(sizeof(*iov) * i);
48 bio_for_each_segment(bv, bio, iter)
49 iov[i++] = (struct iovec) {
50 .iov_base = page_address(bv.bv_page) + bv.bv_offset,
56 .aio_fildes = bio->bi_opf & REQ_FUA
57 ? bio->bi_bdev->bd_sync_fd
58 : bio->bi_bdev->bd_fd,
61 switch (bio_op(bio)) {
63 iocb.aio_lio_opcode = IO_CMD_PREADV;
66 iocb.u.v.offset = bio->bi_iter.bi_sector << 9;
68 if (io_submit(aio_ctx, 1, &iocbp) != 1)
69 die("io_submit err: %m");
72 iocb.aio_lio_opcode = IO_CMD_PWRITEV;
75 iocb.u.v.offset = bio->bi_iter.bi_sector << 9;
77 if (io_submit(aio_ctx, 1, &iocbp) != 1)
78 die("io_submit err: %m");
85 static void submit_bio_wait_endio(struct bio *bio)
87 complete(bio->bi_private);
90 int submit_bio_wait(struct bio *bio)
92 struct completion done;
94 init_completion(&done);
95 bio->bi_private = &done;
96 bio->bi_end_io = submit_bio_wait_endio;
97 bio->bi_opf |= REQ_SYNC;
99 wait_for_completion(&done);
101 return bio->bi_error;
104 int blkdev_issue_discard(struct block_device *bdev,
105 sector_t sector, sector_t nr_sects,
106 gfp_t gfp_mask, unsigned long flags)
111 unsigned bdev_logical_block_size(struct block_device *bdev)
117 ret = fstat(bdev->bd_fd, &statbuf);
120 if (!S_ISBLK(statbuf.st_mode))
121 return statbuf.st_blksize >> 9;
123 ret = ioctl(bdev->bd_fd, BLKPBSZGET, &blksize);
129 sector_t get_capacity(struct gendisk *disk)
131 struct block_device *bdev =
132 container_of(disk, struct block_device, __bd_disk);
137 ret = fstat(bdev->bd_fd, &statbuf);
140 if (!S_ISBLK(statbuf.st_mode))
141 return statbuf.st_size >> 9;
143 ret = ioctl(bdev->bd_fd, BLKGETSIZE64, &bytes);
149 void blkdev_put(struct block_device *bdev, fmode_t mode)
151 fdatasync(bdev->bd_fd);
152 close(bdev->bd_sync_fd);
157 struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
160 struct block_device *bdev;
161 int fd, sync_fd, flags = O_DIRECT;
163 if ((mode & (FMODE_READ|FMODE_WRITE)) == (FMODE_READ|FMODE_WRITE))
165 else if (mode & FMODE_READ)
167 else if (mode & FMODE_WRITE)
171 /* using O_EXCL doesn't work with opening twice for an O_SYNC fd: */
172 if (mode & FMODE_EXCL)
176 fd = open(path, flags);
178 return ERR_PTR(-errno);
180 sync_fd = open(path, flags|O_SYNC);
184 return ERR_PTR(-errno);
187 bdev = malloc(sizeof(*bdev));
188 memset(bdev, 0, sizeof(*bdev));
190 strncpy(bdev->name, path, sizeof(bdev->name));
191 bdev->name[sizeof(bdev->name) - 1] = '\0';
194 bdev->bd_sync_fd = sync_fd;
195 bdev->bd_holder = holder;
196 bdev->bd_disk = &bdev->__bd_disk;
197 bdev->bd_bdi = &bdev->__bd_bdi;
198 bdev->queue.backing_dev_info = bdev->bd_bdi;
203 void bdput(struct block_device *bdev)
208 struct block_device *lookup_bdev(const char *path)
210 return ERR_PTR(-EINVAL);
213 static int aio_completion_thread(void *arg)
215 struct io_event events[8], *ev;
219 ret = io_getevents(aio_ctx, 1, ARRAY_SIZE(events),
222 if (ret < 0 && errno == EINTR)
225 die("io_getevents() error: %m");
227 for (ev = events; ev < events + ret; ev++) {
228 struct bio *bio = (struct bio *) ev->data;
231 bio->bi_error = ev->res;
232 else if (ev->res != bio->bi_iter.bi_size)
233 bio->bi_error = -EIO;
242 __attribute__((constructor(102)))
243 static void blkdev_init(void)
245 struct task_struct *p;
247 if (io_setup(256, &aio_ctx))
248 die("io_setup() error: %m");
250 p = kthread_run(aio_completion_thread, NULL, "aio_completion");