Split I/O code to generic io* and platform specific io_async*

2023-01-18 08:29:08 +00:00
parent 3345936052
commit 76c7819882
99 changed files with 453 additions and 259 deletions
@@ -20,19 +20,21 @@ start:
        mcall   12, 1
        mcall   0, <100,200>, <100,100>, 0x34888888, , window_title
        mcall   12, 2
+
+        DEBUGF 1, "abcde\n"
+        mcall   70, fs70
+        DEBUGF 1, "files in dir: %d\n", ebx
+
        mcall   18, 19, 4, 0
 .next:
        mcall   37, 0
-        add     eax, 0x00030003
+        add     eax, 0x00020002
        mov     edx, eax
        mcall   18, 19, 4
        mcall   5, 1
 ;        mov     ecx, 0x1000000
 ;        loopnz  $
        jmp     .next
-        DEBUGF 1, "abcde\n"
-        mcall   70, fs70
-        DEBUGF 1, "files in dir: %d\n", ebx
        mcall   -1
 exit:
 ;        mcall   18, 9, 2
@@ -0,0 +1,52 @@
+/*
+    SPDX-License-Identifier: GPL-2.0-or-later
+
+    UMKa - User-Mode KolibriOS developer tools
+    io - input/output platform specific code
+
+    Copyright (C) 2023  Ivan Baravy <dunkaist@gmail.com>
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include "io.h"
+#include "io_async.h"
+
+struct umka_io *
+io_init(int *running) {
+    struct umka_io *io = malloc(sizeof(struct umka_io));
+    io->running = running;
+    io->async = io_async_init();
+    return io;
+}
+
+void
+io_close(struct umka_io *io) {
+	io_async_close(io->async);
+    free(io);
+}
+
+ssize_t
+io_read(int fd, void *buf, size_t count, struct umka_io *io) {
+    ssize_t res;
+    if (!*io->running) {
+        res = read(fd, buf, count);
+    } else {
+        res = io_async_read(fd, buf, count, io->async);
+    }
+    return res;
+}
+
+ssize_t
+io_write(int fd, const void *buf, size_t count, struct umka_io *io) {
+    ssize_t res;
+    if (!*io->running) {
+    	res = write(fd, buf, count);
+	} else {
+        res = io_async_write(fd, buf, count, io->async);
+    }
+    return res;
+}
@@ -12,19 +12,21 @@

 #include <unistd.h>

-#define IO_DONT_CHANGE_TASK 0
-#define IO_CHANGE_TASK 1
+struct umka_io {
+    const int *running;
+    void *async;    // platform specific
+};

-void *
-io_init(int change_task);
+struct umka_io *
+io_init(int *running);

 void
-io_close(void *arg);
+io_close(struct umka_io *io);

 ssize_t
-io_read(int fd, void *buf, size_t count, void *arg);
+io_read(int fd, void *buf, size_t count, struct umka_io *io);

 ssize_t
-io_write(int fd, const void *buf, size_t count, void *arg);
+io_write(int fd, const void *buf, size_t count, struct umka_io *io);

 #endif  // IO_H_INCLUDED
@@ -1,51 +0,0 @@
-/*
-    SPDX-License-Identifier: GPL-2.0-or-later
-
-    UMKa - User-Mode KolibriOS developer tools
-    io - input/output platform specific code
-
-    Copyright (C) 2023  Ivan Baravy <dunkaist@gmail.com>
-*/
-
-#include <stdlib.h>
-#include <unistd.h>
-#include "io.h"
-
-struct umka_io {
-    int change_task;
-    int uring_fd;
-};
-
-void *
-io_init(int change_task) {
-    struct umka_io *io = malloc(sizeof(struct umka_io));
-    io->change_task = change_task;
-    if (change_task) {
-        io->uring_fd = 1;
-    }
-    return io;
-}
-
-void
-io_close(void *arg) {
-    struct umka_io *io = arg;
-    free(io);
-}
-
-ssize_t
-io_read(int fd, void *buf, size_t count, void *arg) {
-    struct umka_io *io = arg;
-    (void)io;
-    ssize_t res;
-    res = read(fd, buf, count);
-    return res;
-}
-
-ssize_t
-io_write(int fd, const void *buf, size_t count, void *arg) {
-    struct umka_io *io = arg;
-    (void)io;
-    ssize_t res;
-    res = write(fd, buf, count);
-    return res;
-}
@@ -0,0 +1,212 @@
+/*
+    SPDX-License-Identifier: GPL-2.0-or-later
+
+    UMKa - User-Mode KolibriOS developer tools
+    io_async - input/output platform specific code
+
+    Copyright (C) 2023  Ivan Baravy <dunkaist@gmail.com>
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include <sys/mman.h>
+#include <sys/syscall.h>
+#include <linux/io_uring.h>
+#include "../umka.h"
+
+#define QUEUE_DEPTH 1
+
+#define read_barrier()  __asm__ __volatile__("":::"memory")
+#define write_barrier() __asm__ __volatile__("":::"memory")
+
+#define MAX(x, y) ((x) >= (y) ? (x) : (y))
+
+struct io_uring_queue {
+    int fd;
+    void *base;
+    size_t base_mmap_len;
+    struct io_uring_params p;
+    uint32_t *array;
+    struct io_uring_sqe *sqes;
+    size_t sqes_mmap_len;
+    uint32_t *sq_head, *sq_tail;
+    uint32_t sq_mask;
+    struct io_uring_cqe *cqes;
+    uint32_t *cq_head, *cq_tail;
+    uint32_t cq_mask;
+};
+
+static int
+io_uring_setup(unsigned entries, struct io_uring_params *p) {
+    return (int) syscall(__NR_io_uring_setup, entries, p);
+}
+
+static int
+io_uring_enter(int ring_fd, unsigned int to_submit, unsigned int min_complete,
+               unsigned int flags) {
+    return (int) syscall(__NR_io_uring_enter, ring_fd, to_submit, min_complete,
+                   flags, NULL, 0);
+}
+
+/*
+static void
+dump_scht(char *prefix, struct io_uring_queue *q) {
+fprintf(stderr, "# async %s: %p %p\n", prefix, (void*)q, q->base);
+    size_t head, tail, mask;
+    read_barrier();
+    mask = q->sq_mask;
+    mask = *(uint32_t*)(((uintptr_t)q->base) + q->p.sq_off.ring_mask);
+    head = *q->sq_head & mask;
+    tail = *q->sq_tail & mask;
+fprintf(stderr, "######### %s ######### sq %u:%u 0x%x\n", prefix, head, tail, mask);
+    mask = q->cq_mask;
+    mask = *(uint32_t*)(((uintptr_t)q->base) + q->p.cq_off.ring_mask);
+    head = *q->cq_head & mask;
+    tail = *q->cq_tail & mask;
+fprintf(stderr, "######### %s ######### cq %u:%u 0x%x\n", prefix, head, tail, mask);
+}
+*/
+
+int
+cq_has_data(struct io_uring_queue *q) {
+    size_t head, tail;
+    read_barrier();
+    head = *q->cq_head & q->cq_mask;
+    tail = *q->cq_tail & q->cq_mask;
+    return head != tail;
+}
+
+static void
+build_op_read(struct io_uring_sqe *sqe, int fd, void *data, size_t size,
+              off_t offset) {
+    sqe->fd = fd;
+    sqe->flags = 0;
+    sqe->opcode = IORING_OP_READ;
+    sqe->addr = (uintptr_t)data;
+    sqe->len = size;
+    sqe->off = offset;
+    sqe->user_data = 0;
+}
+
+static int
+read_from_cq(struct io_uring_queue *q) {
+    size_t head, tail;
+    struct io_uring_cqe *cqe;
+    do {
+        read_barrier();
+        head = *q->cq_head & q->cq_mask;
+        tail = *q->cq_tail & q->cq_mask;
+        if (head == tail)
+            break;
+
+        /* Get the entry */
+        cqe = q->cqes + head;
+        if (cqe->res < 0) {
+            fprintf(stderr, "Read error: %s\n", strerror(abs(cqe->res)));
+        }
+        (*q->cq_head)++;
+    } while (head == tail);
+    write_barrier();
+    return cqe->res;
+}
+
+struct io_uring_queue *
+io_async_init() {
+    struct io_uring_queue *q = calloc(1, sizeof(struct io_uring_queue));
+    q->fd = io_uring_setup(QUEUE_DEPTH, &q->p);
+    if (q->fd < 0) {
+        perror("io_uring_setup");
+        return NULL;
+    }
+
+    size_t sring_size = q->p.sq_off.array + q->p.sq_entries * sizeof(unsigned);
+    size_t cring_size = q->p.cq_off.cqes
+                      + q->p.cq_entries * sizeof(struct io_uring_cqe);
+    size_t rings_size = MAX(sring_size, cring_size);
+    q->base_mmap_len = rings_size;
+
+    if (!(q->p.features & IORING_FEAT_SINGLE_MMAP)) {
+        fprintf(stderr, "[io.uring] Your kernel doesn't support"
+                " IORING_FEAT_SINGLE_MMAP, upgrade to Linux 5.4\n");
+        return NULL;
+    }
+
+    q->base = mmap(0, rings_size, PROT_READ | PROT_WRITE, MAP_SHARED
+                   | MAP_POPULATE, q->fd, IORING_OFF_SQ_RING);
+    if (q->base == MAP_FAILED) {
+        perror("[io.uring] Can't mmap io_uring rings");
+        return NULL;
+    }
+
+    q->sqes_mmap_len = q->p.sq_entries * sizeof(struct io_uring_sqe);
+    q->sqes = mmap(0, q->sqes_mmap_len, PROT_READ | PROT_WRITE, MAP_SHARED
+                   | MAP_POPULATE, q->fd, IORING_OFF_SQES);
+    if (q->sqes == MAP_FAILED) {
+        perror("[io.uring] Can't mmap io_uring SQEs");
+        return NULL;
+    }
+
+    q->cqes = (struct io_uring_cqe*)((uintptr_t)q->base + q->p.cq_off.cqes);
+    q->array = (uint32_t*)((uintptr_t)q->base + q->p.sq_off.array);
+    q->sq_head = (uint32_t*)((uintptr_t)q->base + q->p.sq_off.head);
+    q->sq_tail = (uint32_t*)((uintptr_t)q->base + q->p.sq_off.tail);
+    q->sq_mask = *(uint32_t*)((uintptr_t)q->base + q->p.sq_off.ring_mask);
+    q->cq_head = (uint32_t*)((uintptr_t)q->base + q->p.cq_off.head);
+    q->cq_tail = (uint32_t*)((uintptr_t)q->base + q->p.cq_off.tail);
+    q->cq_mask = *(uint32_t*)((uintptr_t)q->base + q->p.cq_off.ring_mask);
+
+    return q;
+}
+
+void
+io_async_close(void *arg) {
+    struct io_uring_queue *q = arg;
+    munmap(q->base, q->base_mmap_len);
+    munmap(q->sqes, q->sqes_mmap_len);
+    close(q->fd);
+    free(q);
+}
+
+static uint32_t
+io_uring_wait_test() {
+    appdata_t *app;
+    __asm__ __volatile__ ("":"=b"(app)::);
+    struct io_uring_queue *q = app->wait_param;
+    int done = cq_has_data(q);
+    return done;
+}
+
+ssize_t
+io_async_read(int fd, void *buf, size_t count, void *arg) {
+    struct io_uring_queue *q = arg;
+    read_barrier();
+    size_t tail = *q->sq_tail & q->sq_mask;
+    struct io_uring_sqe *sqe = q->sqes + tail;
+    build_op_read(sqe, fd, buf, count, -1);
+    q->array[tail] = tail;
+    (*q->sq_tail)++;
+
+    int ret =  io_uring_enter(q->fd, 1, 0, IORING_ENTER_GETEVENTS);
+    if(ret < 0) {
+        perror("io_uring_enter");
+        return 1;
+    }
+
+    kos_wait_events(io_uring_wait_test, q);
+
+    ssize_t res = read_from_cq(q);
+
+    return res;
+}
+
+ssize_t
+io_async_write(int fd, const void *buf, size_t count, void *arg) {
+    (void)fd;
+    (void)buf;
+    (void)count;
+    (void)arg;
+    return -1;
+}
@@ -0,0 +1,27 @@
+/*
+    SPDX-License-Identifier: GPL-2.0-or-later
+
+    UMKa - User-Mode KolibriOS developer tools
+    io_async - input/output platform specific code
+
+    Copyright (C) 2023  Ivan Baravy <dunkaist@gmail.com>
+*/
+
+#ifndef IO_ASYNC_H_INCLUDED
+#define IO_ASYNC_H_INCLUDED
+
+#include <unistd.h>
+
+void *
+io_async_init();
+
+void
+io_async_close(void *arg);
+
+ssize_t
+io_async_read(int fd, void *buf, size_t count, void *arg);
+
+ssize_t
+io_async_write(int fd, const void *buf, size_t count, void *arg);
+
+#endif  // IO_ASYNC_H_INCLUDED
@@ -25,7 +25,7 @@ else
 endif

 CFLAGS=$(WARNINGS) $(NOWARNINGS) -std=c11 -g -O0 -DNDEBUG -masm=intel \
-        -D_POSIX_C_SOURCE=200809L -I$(HOST) -fno-pie
+        -D_POSIX_C_SOURCE=200809L -I$(HOST) -I. -fno-pie
 CFLAGS_32=$(CFLAGS) -m32 -D_FILE_OFFSET_BITS=64 -D__USE_TIME_BITS64
 LDFLAGS=-no-pie
 LDFLAGS_32=$(LDFLAGS) -m32
@@ -57,18 +57,18 @@ test: umka_shell

 umka_shell: umka_shell.o umka.o shell.o trace.o trace_lbr.o vdisk.o \
            vdisk/raw.o vdisk/qcow2.o vdisk/miniz/miniz.a vnet.o lodepng.o \
-            $(HOST)/pci.o $(HOST)/thread.o $(HOST)/io.o util.o optparse.o \
-            bestline.o
+            $(HOST)/pci.o $(HOST)/thread.o io.o $(HOST)/io_async.o util.o \
+            optparse.o bestline.o
 	$(CC) $(LDFLAGS_32) $^ -o $@ -T umka.ld

 umka_fuse: umka_fuse.o umka.o trace.o trace_lbr.o vdisk.o vdisk/raw.o \
           vdisk/qcow2.o vdisk/miniz/miniz.a $(HOST)/pci.o $(HOST)/thread.o \
-           $(HOST)/io.o
+           io.o $(HOST)/io_async.o
 	$(CC) $(LDFLAGS_32) $^ -o $@ `pkg-config fuse3 --libs` -T umka.ld

 umka_os: umka_os.o umka.o shell.o lodepng.o vdisk.o vdisk/raw.o vdisk/qcow2.o \
         vdisk/miniz/miniz.a vnet.o trace.o trace_lbr.o $(HOST)/pci.o \
-         $(HOST)/thread.o $(HOST)/io.o util.o bestline.o optparse.o
+         $(HOST)/thread.o io.o $(HOST)/io_async.o util.o bestline.o optparse.o
 	$(CC) $(LDFLAGS_32) $^ -o $@ -T umka.ld

 umka_gen_devices_dat: umka_gen_devices_dat.o umka.o $(HOST)/pci.o \
@@ -81,8 +81,11 @@ umka.o umka.fas: umka.asm
 shell.o: shell.c lodepng.h
 	$(CC) $(CFLAGS_32) -c $<

-$(HOST)/io.o: $(HOST)/io.c $(HOST)/io.h
-	$(CC) $(CFLAGS_32) -c $< -o $@
+io.o: io.c io.h
+	$(CC) $(CFLAGS_32) -D_DEFAULT_SOURCE -c $< -o $@
+
+$(HOST)/io_async.o: $(HOST)/io_async.c $(HOST)/io_async.h
+	$(CC) $(CFLAGS_32) -D_DEFAULT_SOURCE -c $< -o $@

 $(HOST)/thread.o: $(HOST)/thread.c
 	$(CC) $(CFLAGS_32) -c $< -o $@
@@ -323,7 +323,7 @@ get_last_dir(const char *path) {
 static void
 prompt(struct shell_ctx *ctx) {
    if (cur_dir_changed) {
-        if (ctx->umka && ctx->umka->initialized) {
+        if (ctx->umka->booted) {
            COVERAGE_ON();
            umka_sys_get_cwd(cur_dir, PATH_MAX);
            COVERAGE_OFF();
@@ -405,34 +405,19 @@ cmd_send_scancode(struct shell_ctx *ctx, int argc, char **argv) {
 }

 static void
-cmd_umka_init(struct shell_ctx *ctx, int argc, char **argv) {
+cmd_umka_boot(struct shell_ctx *ctx, int argc, char **argv) {
+    (void)ctx;
+    (void)argv;
    const char *usage = \
-        "usage: umka_init <tool>\n"
-        "  <tool>           number or string: 1=shell, 2=fuse, 3=os";
-    if (argc != 2) {
+        "usage: umka_boot";
+    if (argc != 1) {
        puts(usage);
        return;
    }
-    const char *tool_str = argv[1];
-    unsigned tool;
-    if (!strcmp(tool_str, "1") || !strcmp(tool_str, "shell")) {
-        tool = UMKA_SHELL;
-    } else if (!strcmp(tool_str, "2") || !strcmp(tool_str, "fuse")) {
-        tool = UMKA_FUSE;
-    } else if (!strcmp(tool_str, "3") || !strcmp(tool_str, "os")) {
-        tool = UMKA_OS;
-    } else {
-        printf("[!] bad tool value: '%s'\n", tool_str);
-        return;
-    }

    COVERAGE_ON();
-    ctx->umka = umka_init(tool);
+    umka_boot();
    COVERAGE_OFF();
-
-    if (!ctx->umka) {
-        printf("![shell] can't init umka\n");
-    }
 }

 static void
@@ -3706,7 +3691,7 @@ static void cmd_help(struct shell_ctx *ctx, int argc, char **argv);

 func_table_t cmd_cmds[] = {
    { "send_scancode",                  cmd_send_scancode },
-    { "umka_init",                      cmd_umka_init },
+    { "umka_boot",                      cmd_umka_boot },
    { "umka_set_boot_params",           cmd_umka_set_boot_params },
    { "acpi_call",                      cmd_acpi_call },
    { "acpi_enable",                    cmd_acpi_enable },
@@ -3912,9 +3897,10 @@ run_test(struct shell_ctx *ctx) {
 }

 struct shell_ctx *
-shell_init(int reproducible, const char *hist_file, struct umka_io *io) {
+shell_init(int reproducible, const char *hist_file, struct umka_ctx *umka,
+           struct umka_io *io) {
    struct shell_ctx *ctx = malloc(sizeof(struct shell_ctx));
-    ctx->umka = NULL;
+    ctx->umka = umka;
    ctx->io = io;
    ctx->reproducible = reproducible;
    ctx->hist_file = hist_file;
@@ -33,7 +33,7 @@ struct shell_var {
 };

 struct shell_ctx {
-    struct umka_ctx *umka;
+    const struct umka_ctx *umka;
    struct umka_io *io;
    int reproducible;
    const char *hist_file;
@@ -41,7 +41,8 @@ struct shell_ctx {
 };

 struct shell_ctx *
-shell_init(int reproducible, const char *hist_file, struct umka_io *io);
+shell_init(int reproducible, const char *hist_file, struct umka_ctx *umka,
+           struct umka_io *io);

 void
 shell_close(struct shell_ctx *shell);
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_ftype1_s05k_b2k_n8k.qcow2 hd0 -c 0
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_ftype1_s05k_b2k_n8k.qcow2 hd0 -c 0
 disk_add ../img/xfs_short_dir_i8.qcow2 hd1 -c 0

@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_ftype0_s05k_b2k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_ftype0_s05k_b2k_n8k.qcow2 hd0 -c 524288
 ls70 /hd0/1/sf_empty
 ls70 /hd0/1/sf
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 # zero length
 read70 /hd0/1/no_hole 0 0 -b
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 stat70 /hd0/1/
 stat70 /hd0/1/hole_begin
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 pwd
 cd /hd0
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 # hole begin
 # zero length
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_ftype1_s05k_b2k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_ftype1_s05k_b2k_n8k.qcow2 hd0 -c 524288
 stat70 /hd0/1/sf_empty
 stat70 /hd0/1/sf_empty/.
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_ftype0_s4k_b4k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=4096, capacity=77312 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=256 (1 MiB), length=76800 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_ftype0_s4k_b4k_n8k.qcow2 hd0 -c 524288
 ls70 /hd0/1/sf
 ls70 /hd0/1/block
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_ftype0_s05k_b2k_n8k_xattr.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_ftype0_s05k_b2k_n8k_xattr.qcow2 hd0 -c 524288
 ls70 /hd0/1/sf_empty
 ls70 /hd0/1/sf
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_ftype0_s05k_b2k_n8k_xattr.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_ftype0_s05k_b2k_n8k_xattr.qcow2 hd0 -c 524288
 stat70 /hd0/1/sf_empty
 stat70 /hd0/1/sf_empty/.
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_unicode.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_unicode.qcow2 hd0 -c 524288

 stat80 /hd0/1/dir0
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v5_ftype1_s05k_b2k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v5_ftype1_s05k_b2k_n8k.qcow2 hd0 -c 524288
 ls70 /hd0/1/sf_empty
 ls70 /hd0/1/sf
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v5_ftype1_s05k_b2k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v5_ftype1_s05k_b2k_n8k.qcow2 hd0 -c 524288
 stat70 /hd0/1/sf_empty
 stat70 /hd0/1/sf_empty/.
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v5_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v5_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 # hole begin
 # zero length
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v5_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v5_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 # zero length
 read70 /hd0/1/no_hole 0 0 -b
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> set_mouse_pos_screen 40 30
 /> #disk_add ../img/kolibri.raw rd -c 0
 /> ramdisk_init ../img/kolibri.raw
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 set_mouse_pos_screen 40 30
 #disk_add ../img/kolibri.raw rd -c 0
 ramdisk_init ../img/kolibri.raw
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_files_s05k_b4k_n8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_files_s05k_b4k_n8k.qcow2 hd0 -c 524288

 read70 /hd0/1/4GiB_plus 0x3ff4 11 -b
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/jfs.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=32768 (16 MiB), num_partitions=1
 /hd0/1: fs=???, start=2048 (1 MiB), length=28672 (14 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/jfs.qcow2 hd0 -c 524288
 disk_del hd0
 disk_add ../img/xfs_borg_bit.qcow2 hd0 -c 524288
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_v4_btrees_l2.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_v4_btrees_l2.qcow2 hd0 -c 524288

 ls80 /hd0/1/dir_btree_l2 -f 0 -c 1
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> i40 18 16
 eax = 00040000  262144  262144
 ebx = 00000010  16  16
@@ -1,2 +1,2 @@
-umka_init shell
+umka_boot
 i40 18 16
@@ -1,5 +1,5 @@
 /> umka_set_boot_params --x_res 44 --y_res 44
-/> umka_init shell
+/> umka_boot
 /> ramdisk_init ../img/kolibri.raw
 /rd: sector_size=512, capacity=2880 (1440 kiB), num_partitions=1
 /rd/1: fs=fat, start=0 (0 B), length=2880 (1440 kiB)
@@ -1,5 +1,5 @@
 umka_set_boot_params --x_res 44 --y_res 44
-umka_init shell
+umka_boot
 ramdisk_init ../img/kolibri.raw
 set_skin /sys/DEFAULT.SKN

@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/fat32_test0.raw hd0 -c 0
 /hd0: sector_size=512, capacity=131072 (64 MiB), num_partitions=1
 /hd0/1: fs=fat, start=2048 (1 MiB), length=126976 (62 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/fat32_test0.raw hd0 -c 0
 ls80 /hd0/1/
 read70 /hd0/1/A 0 16388096 -h
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/exfat_s05k_c16k_b16k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=exfat, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/exfat_s05k_c16k_b16k.qcow2 hd0 -c 524288

 ls70 /hd0/1/dir_0 -f 0 -c 0
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/exfat_s05k_c8k_b8k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=exfat, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/exfat_s05k_c8k_b8k.qcow2 hd0 -c 524288

 stat70 /hd0/1/dir_000
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> 
 /> get_keyboard_mode
 keyboard_mode: 0 - ASCII
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot

 get_keyboard_mode
 get_keyboard_lang
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> 
 /> get_mouse_pos_screen
 x y: 200 150
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot

 get_mouse_pos_screen
 get_mouse_pos_window
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> #set_mouse_pos_screen 40 30
 /> ramdisk_init ../img/kolibri.raw
 /rd: sector_size=512, capacity=2880 (1440 kiB), num_partitions=1
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 #set_mouse_pos_screen 40 30
 ramdisk_init ../img/kolibri.raw
 set_skin /sys/DEFAULT.SKN
@@ -1,3 +1,3 @@
-umka_init shell
+umka_boot
 check_for_event
 check_for_event
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> 
 /> ramdisk_init ../img/kolibri.raw
 /rd: sector_size=512, capacity=2880 (1440 kiB), num_partitions=1
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot

 ramdisk_init ../img/kolibri.raw
 set_skin /sys/DEFAULT.SKN
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_bigtime.qcow2 hd0 -c 0
 /hd0: sector_size=512, capacity=618496 (302 MiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=614400 (300 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_bigtime.qcow2 hd0 -c 0
 ls70 /hd0/1/
 ls70 /hd0/1/dira
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_nrext64.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=6291456 (3 GiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=6287360 (3070 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_nrext64.qcow2 hd0 -c 524288
 stat70 /hd0/1/dir_sf
 stat70 /hd0/1/dir_block
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_lookup_v5.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=10485760 (5 GiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=10481664 (5118 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_lookup_v5.qcow2 hd0 -c 524288
 cd /hd0/1/dir_sf
 stat70 d0000000000/d0000000000
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_lookup_v4.qcow2 hd0 -c 1048576
 /hd0: sector_size=512, capacity=6291456 (3 GiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=6287360 (3070 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_lookup_v4.qcow2 hd0 -c 1048576
 cd /hd0/1/dir_sf
 stat70 d0000000000/d0000000000
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/gpt_partitions_s05k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=2097152 (1 GiB), num_partitions=24
 /hd0/1: fs=???, start=2048 (1 MiB), length=2048 (1 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/gpt_partitions_s05k.qcow2 hd0 -c 524288
 disk_del hd0
 disk_add ../img/gpt_partitions_s4k.qcow2 hd0 -c 524288
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/ext2_s05k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=10485760 (5 GiB), num_partitions=1
 /hd0/1: fs=ext, start=2048 (1 MiB), length=10481664 (5118 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/ext2_s05k.qcow2 hd0 -c 524288
 ls70 /hd0/1/dir_a
 ls70 /hd0/1/dir_b
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/ext4_s05k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=10485760 (5 GiB), num_partitions=1
 /hd0/1: fs=???, start=2048 (1 MiB), length=10481664 (5118 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/ext4_s05k.qcow2 hd0 -c 524288
 ls70 /hd0/1/dir_a
 ls70 /hd0/1/dir_b
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/fat12_s05k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=524288 (256 MiB), num_partitions=1
 /hd0/1: fs=fat, start=2048 (1 MiB), length=520192 (254 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/fat12_s05k.qcow2 hd0 -c 524288
 ls70 /hd0/1/dir_a
 ls70 /hd0/1/dir_b
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/fat16_s05k.qcow2 hd0 -c 524288
 /hd0: sector_size=512, capacity=8388608 (4 GiB), num_partitions=1
 /hd0/1: fs=fat, start=2048 (1 MiB), length=8384481 (4292854272 B)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/fat16_s05k.qcow2 hd0 -c 524288
 ls70 /hd0/1/dir_a
 ls70 /hd0/1/dir_b
@@ -1,4 +1,4 @@
-/> umka_init shell
+/> umka_boot
 /> disk_add ../img/xfs_samehash_s05k.raw hd0 -c 0
 /hd0: sector_size=512, capacity=2097152 (1 GiB), num_partitions=1
 /hd0/1: fs=xfs, start=2048 (1 MiB), length=2093056 (1022 MiB)
@@ -1,4 +1,4 @@
-umka_init shell
+umka_boot
 disk_add ../img/xfs_samehash_s05k.raw hd0 -c 0
 ls70 /hd0/1/dir_sf
 ls70 /hd0/1/dir_block
@@ -116,6 +116,7 @@ pubsym sha3_256_oneshot, 'hash_oneshot'
 pubsym kos_time_to_epoch
 pubsym umka_init, 4
 pubsym umka_close, 4
+pubsym umka_boot

 pubsym current_process, 'kos_current_process'
 pubsym current_slot, 'kos_current_slot'
@@ -570,18 +571,15 @@ proc kos_eth_input c uses ebx esi edi ebp, buffer_ptr
 endp

 struct umka_ctx
-        tool dd ?
-        initialized dd ?
+        booted dd ?
+        running dd ?
 ends

-proc umka_init c uses ebx esi edi ebp, _tool
+proc umka_init c uses ebx esi edi ebp
        call    umka._.check_alignment
-        stdcall kos_init
-        stdcall kernel_alloc, sizeof.umka_ctx
-        mov     ecx, [_tool]
-        mov     [umka_tool], ecx
-        mov     [eax+umka_ctx.tool], ecx
-        mov     [eax+umka_ctx.initialized], 1
+        mov     eax, umka
+        mov     [eax+umka_ctx.booted], 0
+        mov     [eax+umka_ctx.running], 0
        ret
 endp

@@ -590,7 +588,8 @@ proc umka_close c, _ctx
        ret
 endp

-proc kos_init uses ebx esi edi ebp
+proc umka_boot uses ebx esi edi ebp
+        mov     [umka.booted], 1
        mov     edi, endofcode
        mov     ecx, uglobals_size
        xor     eax, eax
@@ -1035,8 +1034,8 @@ bios32_entry equ bios32_entry_pew
 tmp_page_tabs equ tmp_page_tabs_pew
 macro jmp target {
  if target eq osloop
-        cmp     [umka_tool], UMKA_SHELL
-        jnz     osloop
+        cmp     [umka.running], 1
+        jz      osloop
        ret
  else
        jmp     target
@@ -1079,7 +1078,7 @@ else
    error "Your OS is not supported"
 end if

-umka_tool dd ?
+umka umka_ctx
 fpu_owner dd ?

 uglobal
@@ -29,8 +29,8 @@ typedef void siginfo_t;
 #define STDCALL __attribute__((__stdcall__))

 struct umka_ctx {
-    uint32_t tool;
-    uint32_t initialized;
+    int booted;
+    int running;
 };

 #define UMKA_DEFAULT_DISPLAY_BPP 32
@@ -547,6 +547,9 @@ umka_init(int tool);
 void
 umka_close(struct umka_ctx *ctx);

+void
+umka_boot(void);
+
 void
 i40(void);

@@ -36,8 +36,8 @@ struct umka_fuse_ctx {
 static struct umka_fuse_ctx *
 umka_fuse_init() {
    struct umka_fuse_ctx *ctx = malloc(sizeof(struct umka_fuse_ctx));
-    ctx->umka = NULL;
-    ctx->io = io_init(IO_DONT_CHANGE_TASK);
+    ctx->umka = umka_init(UMKA_FUSE);
+    ctx->io = io_init(&ctx->umka->running);
    return ctx;
 }

@@ -52,10 +52,10 @@ hw_int_mouse(void *arg) {
 struct umka_os_ctx *
 umka_os_init() {
    struct umka_os_ctx *ctx = malloc(sizeof(struct umka_os_ctx));
-    ctx->umka = NULL;
-    ctx->io = io_init(IO_DONT_CHANGE_TASK);
+    ctx->umka = umka_init(UMKA_OS);
+    ctx->io = io_init(&ctx->umka->running);
    ctx->shell = shell_init(SHELL_LOG_NONREPRODUCIBLE, history_filename,
-                            ctx->io);
+                            ctx->umka, ctx->io);
    return ctx;
 }

@@ -315,6 +315,7 @@ main(int argc, char *argv[]) {

    setitimer(ITIMER_PROF, &timeout, NULL);

+    ctx->umka->running = 1;
    umka_osloop();   // doesn't return

    if (coverage)
@@ -1,4 +1,4 @@
-umka_init os
+umka_boot
 ramdisk_init ../img/kolibri.raw
 set_skin /sys/DEFAULT.SKN
 disk_add ../img/xfs_samehash_s05k.raw  hd0 -c 0
@@ -33,9 +33,9 @@ char history_filename[PATH_MAX];
 struct umka_shell_ctx *
 umka_shell_init(int reproducible) {
    struct umka_shell_ctx *ctx = malloc(sizeof(struct umka_shell_ctx));
-    ctx->umka = NULL;
-    ctx->io = io_init(IO_DONT_CHANGE_TASK);
-    ctx->shell = shell_init(reproducible, history_filename, ctx->io);
+    ctx->umka = umka_init(UMKA_SHELL);
+    ctx->io = io_init(&ctx->umka->running);
+    ctx->shell = shell_init(reproducible, history_filename, ctx->umka, ctx->io);
    return ctx;
 }

@@ -49,10 +49,10 @@ vdisk_init(const char *fname, int adjust_cache_size, size_t cache_size,
    struct vdisk *disk;
    if (fname_len > dot_raw_len
        && !strcmp(fname + fname_len - dot_raw_len, RAW_SUFFIX)) {
-        disk = (struct vdisk*)vdisk_init_raw(fname);
+        disk = (struct vdisk*)vdisk_init_raw(fname, io);
    } else if (fname_len > dot_qcow2_len
               && !strcmp(fname + fname_len - dot_qcow2_len, QCOW2_SUFFIX)) {
-        disk = (struct vdisk*)vdisk_init_qcow2(fname);
+        disk = (struct vdisk*)vdisk_init_qcow2(fname, io);
    } else {
        fprintf(stderr, "[vdisk] file has unknown format: %s\n", fname);
        return NULL;
@@ -14,6 +14,7 @@
 #include "../trace.h"
 #include "qcow2.h"
 #include "miniz/miniz.h"
+#include "io.h"

 struct vdisk_qcow2 {
    struct vdisk vdisk;
@@ -96,7 +97,7 @@ qcow2_read_guest_sector(struct vdisk_qcow2 *d, uint64_t sector, uint8_t *buf) {
    uint64_t l2_entry;
    uint64_t l1_entry_offset = d->l1_table_offset + l1_index*sizeof(l1_entry);
    lseek(d->fd, l1_entry_offset, SEEK_SET);
-    if (!read(d->fd, &l1_entry, sizeof(l1_entry))) {
+    if (!io_read(d->fd, &l1_entry, sizeof(l1_entry), d->vdisk.io)) {
        fprintf(stderr, "[vdisk.qcow2] can't read from image file: %s\n",
                strerror(errno));
        return;
@@ -109,7 +110,7 @@ qcow2_read_guest_sector(struct vdisk_qcow2 *d, uint64_t sector, uint8_t *buf) {
        return;
    }
    lseek(d->fd, l2_table_offset + l2_index*sizeof(l2_entry), SEEK_SET);
-    if (!read(d->fd, &l2_entry, sizeof(l2_entry))) {
+    if (!io_read(d->fd, &l2_entry, sizeof(l2_entry), d->vdisk.io)) {
        fprintf(stderr, "[vdisk.qcow2] can't read from image file: %s\n",
                strerror(errno));
        return;
@@ -124,7 +125,7 @@ qcow2_read_guest_sector(struct vdisk_qcow2 *d, uint64_t sector, uint8_t *buf) {
        }
        cluster_offset = l2_entry & L2_ENTRY_STD_OFFSET;
        lseek(d->fd, cluster_offset, SEEK_SET);
-        if (!read(d->fd, d->cluster, d->cluster_size)) {
+        if (!io_read(d->fd, d->cluster, d->cluster_size, d->vdisk.io)) {
            fprintf(stderr, "[vdisk.qcow2] can't read from image file: %s\n",
                    strerror(errno));
            return;
@@ -139,7 +140,7 @@ qcow2_read_guest_sector(struct vdisk_qcow2 *d, uint64_t sector, uint8_t *buf) {
        size_t additional_sectors = (l2_entry & d->l2_entry_cmp_sect_cnt_mask)
                                    >> d->l2_entry_cmp_x;
        size_t cmp_size = 512 - (cmp_offset & 511) + additional_sectors*512;
-        if (!read(d->fd, d->cmp_cluster, d->cluster_size)) {
+        if (!io_read(d->fd, d->cmp_cluster, d->cluster_size, d->vdisk.io)) {
            fprintf(stderr, "[vdisk.qcow2] can't read from image file: %s\n",
                    strerror(errno));
            return;
@@ -193,7 +194,7 @@ vdisk_qcow2_write(void *userdata, void *buffer, off_t startsector,
 }

 struct vdisk*
-vdisk_init_qcow2(const char *fname) {
+vdisk_init_qcow2(const char *fname, struct umka_io *io) {
    struct vdisk_qcow2 *d =
        (struct vdisk_qcow2*)calloc(1, sizeof(struct vdisk_qcow2));
    d->vdisk.diskfunc = (diskfunc_t) {.strucsize = sizeof(diskfunc_t),
@@ -201,6 +202,7 @@ vdisk_init_qcow2(const char *fname) {
                                      .read = vdisk_qcow2_read,
                                      .write = vdisk_qcow2_write,
                                     };
+    d->vdisk.io = io;
    if (!d) {
        fprintf(stderr, "[vdisk.qcow2] can't allocate memory: %s\n",
                strerror(errno));
@@ -219,7 +221,7 @@ vdisk_init_qcow2(const char *fname) {
    }

    struct qcow2_header header;
-    if (!read(d->fd, &header, sizeof(struct qcow2_header))) {
+    if (!io_read(d->fd, &header, sizeof(struct qcow2_header), d->vdisk.io)) {
        fprintf(stderr, "[vdisk.qcow2] can't read from image file: %s\n",
                strerror(errno));
        vdisk_qcow2_close(d);
@@ -11,11 +11,12 @@
 #define VDISK_QCOW2_H_INCLUDED

 #include <stdio.h>
-#include "../vdisk.h"
+#include "vdisk.h"
+#include "io.h"

 #define QCOW2_SUFFIX ".qcow2"

 struct vdisk*
-vdisk_init_qcow2(const char *fname);
+vdisk_init_qcow2(const char *fname, struct umka_io *io);

 #endif  // VDISK_QCOW2_H_INCLUDED
@@ -54,8 +54,8 @@ vdisk_raw_write(void *userdata, void *buffer, off_t startsector,
 }

 struct vdisk*
-vdisk_init_raw(const char *fname) {
-    int fd = open(fname, O_RDWR);
+vdisk_init_raw(const char *fname, struct umka_io *io) {
+    int fd = open(fname, O_RDONLY);
    if (!fd) {
        printf("[vdisk.raw]: can't open file '%s': %s\n", fname, strerror(errno));
        return NULL;
@@ -75,6 +75,7 @@ vdisk_init_raw(const char *fname) {
                                  },
                      .sect_size = sect_size,
                      .sect_cnt = (uint64_t)fsize / sect_size,
+                      .io = io,
                     },
            .fd = fd,
            };
@@ -11,11 +11,12 @@
 #define VDISK_RAW_H_INCLUDED

 #include <stdio.h>
-#include "../vdisk.h"
+#include "vdisk.h"
+#include "io.h"

 #define RAW_SUFFIX ".raw"

 struct vdisk*
-vdisk_init_raw(const char *fname);
+vdisk_init_raw(const char *fname, struct umka_io *io);

 #endif  // VDISK_RAW_H_INCLUDED
@@ -1,27 +0,0 @@
-/*
-    SPDX-License-Identifier: GPL-2.0-or-later
-
-    UMKa - User-Mode KolibriOS developer tools
-    io - input/output platform specific code
-
-    Copyright (C) 2023  Ivan Baravy <dunkaist@gmail.com>
-*/
-
-#include <unistd.h>
-#include "io.h"
-
-ssize_t
-io_read(int fd, void *buf, size_t count, int change_task) {
-    (void)change_task;
-    ssize_t res;
-    res = read(fd, buf, count);
-    return res;
-}
-
-ssize_t
-io_write(int fd, const void *buf, size_t count, int change_task) {
-    (void)change_task;
-    ssize_t res;
-    res = write(fd, buf, count);
-    return res;
-}
@@ -1,21 +0,0 @@
-/*
-    SPDX-License-Identifier: GPL-2.0-or-later
-
-    UMKa - User-Mode KolibriOS developer tools
-    io - input/output platform specific code
-
-    Copyright (C) 2023  Ivan Baravy <dunkaist@gmail.com>
-*/
-
-#ifndef IO_H_INCLUDED
-#define IO_H_INCLUDED
-
-#include <unistd.h>
-
-ssize_t
-io_read(int fd, void *buf, size_t count, int change_task);
-
-ssize_t
-io_write(int fd, const void *buf, size_t count, int change_task);
-
-#endif  // IO_H_INCLUDED