Files
2026-10-25 19:07:58 +01:00

79 lines
2.1 KiB
C

// SPDX-License-Identifier: ISC
#include <zinnia/alloc.h>
#include <zinnia/atomic.h>
#include <zinnia/blockdev.h>
#include <stdint.h>
struct partition {
struct blockdev blk;
struct blockdev* parent;
uint64_t start;
};
static _Atomic(uint32_t) next_minor;
static errno_t partition_submit(struct blockdev* blk, struct bio* bio) {
struct partition* part = containerof(blk, struct partition, blk);
struct blockdev* parent = part->parent;
if (bio->op != BIO_FLUSH) {
if (bio->lba >= blk->lba_count) {
bio_complete(bio, bio->op == BIO_READ ? 0 : ENOSPC, 0);
return 0;
}
if (bio->op == BIO_WRITE && bio->num_lbas > blk->lba_count - bio->lba) {
bio_complete(bio, ENOSPC, 0);
return 0;
}
bio->lba += part->start;
}
return parent->ops->submit(parent, bio);
}
static errno_t partition_ioctl(
struct blockdev* blk,
struct vfs_file* file,
uintptr_t request,
uintptr_t arg,
uintptr_t* out
) {
struct blockdev* parent = containerof(blk, struct partition, blk)->parent;
if (!parent->ops->ioctl)
return ENOTTY;
return parent->ops->ioctl(parent, file, request, arg, out);
}
static void partition_destroy(struct blockdev* blk) {
struct partition* part = containerof(blk, struct partition, blk);
blockdev_unref(part->parent);
mem_free(part);
}
static const struct blockdev_ops partition_ops = {
.submit = partition_submit,
.ioctl = partition_ioctl,
.destroy = partition_destroy,
};
errno_t partition_new(struct blockdev* parent, uint64_t start_lba, uint64_t lba_count, struct blockdev** out) {
struct partition* part = mem_alloc(sizeof(struct partition), 0);
if (!part)
return ENOMEM;
blockdev_init(
&part->blk,
&partition_ops,
259,
atomic_fetch_add(&next_minor, 1, ATOMIC_RELAXED),
parent->lba_size,
lba_count
);
part->blk.limits = parent->limits;
blockdev_ref(parent);
part->parent = parent;
part->start = start_lba;
*out = &part->blk;
return 0;
}