The ATA driver: hard disks on the IDE controller, as block device 3 (/dev/hda and up). More...

#include <core/system.h>
#include <core/module.h>
#include <core/kargs.h>
#include <cpu/io.h>
#include <dev/dev.h>
#include <fs/vfs.h>
#include <fs/devfs.h>
#include <fs/posix.h>
#include <fs/mbr.h>
#include <aquila/errno.h>
#include <dev/pci.h>
#include <dev/blkcache.h>
#include <dev/irq.h>
#include <sys/sched.h>
#include <ata.h>

Macros
#define	BLOCK_SIZE 512UL

Functions
static void	channel_acquire (struct ata_channel *ch)
	Takes a channel for one command, waiting while another runs (a DMA request sleeps).
static void	channel_release (struct ata_channel *ch)
	Gives a channel back, and wakes up the requests waiting for it.
static ssize_t	drive_read (void _drive, uint64_t lba, size_t count, void buf)
	Reads sectors from a drive, for the block cache: the channel is held for the command only, and the buffer is the cache's.
static ssize_t	drive_write (void _drive, uint64_t lba, size_t count, void buf)
	Writes sectors to a drive, for the block cache.
static void	ata_irq (void *channel)
	Handles a channel's interrupt.
void	ata_reset (struct ata_drive *drive)
	Resets both drives on a drive's channel, and waits until they are done.
void	ata_select_drive (struct ata_drive *drive, uint32_t mode)
	Selects a drive on its channel, for an addressing mode, if it isn't selected so already, and waits for the drive to take it.
void	ata_setup (struct ata_drive *drive, uint64_t lba, size_t count)
	Writes the registers of a command on count sectors from lba: the drive, the address and the count.
static int	ata_partition (struct ata_drive drive, size_t part, uint64_t start, uint64_t *nsectors)
	Finds partition part of a drive (1 to 4; 0 is the whole disk): its first sector and how many sectors it has, from the MBR, which is read once.
static int	ata_locate (struct devid dd, int write, struct ata_drive ref, uint64_t start, uint64_t *nsectors)
	Finds the drive of a device number, and where its partition is on it.
static ssize_t	ata_read (struct devid dd, off_t offset, size_t size, void buf)
	Reads sectors of a partition, from sector offset on, through the block cache.
static ssize_t	ata_write (struct devid dd, off_t offset, size_t size, void buf)
	Writes sectors of a partition, from sector offset on, through the block cache.
static int	ata_drive_present (struct ata_drive *drive)
	Returns whether the selected drive is there.
static uint8_t	ata_detect_drive (struct ata_drive *drive)
	Detects what a drive is (ATADEV_*).
static int	ata_sync (void)
	Has every drive write what its cache holds to the disk, for sync().
static size_t	ata_getbs (struct devid *dd)
	Returns the block size: one sector, 512 bytes.
static int	ata_probe ()
	Finds the IDE controller, detects its drives, sets them up, and registers the disks as block device 3.

Variables
static struct ata_drive	drives [4]
static struct ata_channel	channels [2]
static struct ata_drive *	last_selected_drive = NULL
static uint32_t	last_selected_mode = -1
struct dev	atadev

Detailed Description

The ATA driver: hard disks on the IDE controller, as block device 3 (/dev/hda and up).

The driver finds the IDE controller on the PCI bus, detects the four drives its two channels may have, and moves their sectors by PIO (pio.c) or bus master DMA (dma.c). Minor numbers are 64 per drive: 0 is the whole disk, 1 to 4 its primary partitions, from the MBR. Reads and writes go through the block cache (blkcache.c). One command at a time runs on a channel. Only ATA hard disks are supported: not ATAPI (CD-ROMs), and not SATA's own interface.

Definition in file ata.c.

Macro Definition Documentation

◆ BLOCK_SIZE

#define BLOCK_SIZE 512UL

Definition at line 33 of file ata.c.

Referenced by ata_getbs(), and ata_partition().

Function Documentation

◆ ata_detect_drive()

uint8_t ata_detect_drive ( struct ata_drive * drive )

static

Detects what a drive is (ATADEV_*).

An ATA disk's IDENTIFY reply gives its size, its capabilities and its model.

Definition at line 328 of file ata.c.

References ATA_CMD_IDENTIFY, ATA_CMD_IDENTIFY_PACKET, ata_detect_drive(), ata_drive_present(), ATA_IDENT_CAPABILITIES, ATA_IDENT_COMMANDSETS, ATA_IDENT_DEVICETYPE, ATA_IDENT_MAX_LBA, ATA_IDENT_MAX_LBA_EXT, ATA_IDENT_MODEL, ATA_MODE_LBA28, ATA_MODE_LBA48, ATA_REG_CMD, ATA_REG_DATA, ATA_REG_LBA1, ATA_REG_LBA2, ATA_REG_STATUS, ata_reset(), ata_select_drive(), ATADEV_NOTFOUND, ATADEV_PATA, ATADEV_PATAPI, ATADEV_SATA, ATADEV_SATAPI, ATADEV_UNKNOWN, ata_drive::base, ata_drive::capabilities, ata_drive::command_sets, ata_drive::id, io_in16(), io_in8(), io_out8(), ata_drive::max_lba, memset(), ata_drive::mode, ata_drive::model, printk(), ata_drive::signature, ata_drive::slave, and ata_drive::type.

Referenced by ata_detect_drive(), and ata_probe().

◆ ata_drive_present()

int ata_drive_present ( struct ata_drive * drive )

static

Returns whether the selected drive is there.

It must be called once the channel's reset is done. A floating bus (no drive on the channel) reads 0xFF, and a missing drive next to a present one reads 0.

Definition at line 308 of file ata.c.

References ata_drive_present(), ATA_REG_LBA1, ATA_REG_LBA2, ATA_REG_STATUS, ATA_STATUS_BSY, ATA_STATUS_DRDY, ata_drive::base, and io_in8().

Referenced by ata_detect_drive(), and ata_drive_present().

◆ ata_getbs()

size_t ata_getbs ( struct devid * dd )

static

Returns the block size: one sector, 512 bytes.

Definition at line 446 of file ata.c.

References ata_getbs(), and BLOCK_SIZE.

Referenced by ata_getbs().

◆ ata_irq()

void ata_irq ( void * channel )

static

Handles a channel's interrupt.

Definition at line 82 of file ata.c.

References ata_irq(), ata_drive::channel, and dma_irq().

Referenced by ata_irq(), and ata_probe().

◆ ata_locate()

int ata_locate	(	struct devid *	dd,
		int	write,
		struct ata_drive **	ref,
		uint64_t *	start,
		uint64_t *	nsectors )

static

Finds the drive of a device number, and where its partition is on it.

Returns 0 or a negative errno (-ENXIO if there is no such drive or partition).

Definition at line 240 of file ata.c.

References ata_locate(), ata_partition(), ata_drive::channel, channel_acquire(), channel_release(), drives, devid::minor, ata_drive::read, and ata_drive::write.

Referenced by ata_locate(), ata_read(), and ata_write().

◆ ata_partition()

int ata_partition	(	struct ata_drive *	drive,
		size_t	part,
		uint64_t *	start,
		uint64_t *	nsectors )

static

Finds partition part of a drive (1 to 4; 0 is the whole disk): its first sector and how many sectors it has, from the MBR, which is read once.

Returns 0, -ENXIO if the MBR has no partition there (no signature, an empty entry, or one past the disk's end), -EIO if the MBR can't be read, or -ENOMEM.

The MBR is read into a buffer of its own: lookups on the two channels may run at once, each sleeping while its read is done.

Definition at line 192 of file ata.c.

References ata_partition(), BLOCK_SIZE, mbr::boot_signature, kfree(), kmalloc(), ata_drive::max_lba, ata_drive::poff, ata_drive::psize, mbr::ptab, ata_drive::read, mbr_part::sectors_count, mbr_part::start_lba, and mbr_part::type.

Referenced by ata_locate(), and ata_partition().

◆ ata_probe()

int ata_probe ( )

static

Finds the IDE controller, detects its drives, sets them up, and registers the disks as block device 3.

Definition at line 453 of file ata.c.

References ioaddr::addr, ata_detect_drive(), ata_irq(), ATA_PIO_PRI_PORT_BASE, ATA_PIO_PRI_PORT_CONTROL, ATA_PIO_SEC_PORT_BASE, ATA_PIO_SEC_PORT_CONTROL, ata_probe(), atadev, ATADEV_NOTFOUND, ATADEV_PATA, ATADEV_PATAPI, ATADEV_SATA, ATADEV_SATAPI, ata_channel::base, ata_drive::base, ata_channel::bm, pci_dev::bus, channels, ata_drive::ctrl, pci_dev::dev, dma_init(), drives, pci_dev::func, ata_drive::id, IOADDR_PORT, ata_channel::irq, irq_install(), kargs_get(), kdev_blkdev_register(), NULL, pci_irq(), pci_read_bar(), pci_reg16_read(), pci_reg16_write(), pci_scan_device(), pio_init(), printk(), ata_drive::slave, and ioaddr::type.

Referenced by ata_probe().

◆ ata_read()

ssize_t ata_read	(	struct devid *	dd,
		off_t	offset,
		size_t	size,
		void *	buf )

static

Reads sectors of a partition, from sector offset on, through the block cache.

Returns how many were read (none past the partition's end), or a negative errno.

Definition at line 266 of file ata.c.

References ata_locate(), ata_read(), blkcache_read(), drive_read(), ata_drive::max_lba, and MIN.

Referenced by ata_read().

◆ ata_reset()

void ata_reset ( struct ata_drive * drive )

Resets both drives on a drive's channel, and waits until they are done.

Parameters

drive a drive on the channel

Definition at line 97 of file ata.c.

References ATA_CMD_RESET, ATA_REG_HDDEVSEL, ata_reset(), ATA_STATUS_BSY, ATA_TIMEOUT, ata_drive::base, ata_drive::ctrl, io_in8(), io_out8(), last_selected_drive, last_selected_mode, and NULL.

Referenced by ata_detect_drive(), ata_reset(), and pio_init().

◆ ata_select_drive()

void ata_select_drive	(	struct ata_drive *	drive,
		uint32_t	mode )

Selects a drive on its channel, for an addressing mode, if it isn't selected so already, and waits for the drive to take it.

Parameters

drive	the drive
mode	the addressing mode (ATA_MODE_*), or 0 to detect it

Definition at line 126 of file ata.c.

References ATA_MODE_LBA28, ATA_MODE_LBA48, ATA_REG_HDDEVSEL, ata_select_drive(), ata_drive::base, io_out8(), last_selected_drive, last_selected_mode, ata_drive::mode, and ata_drive::slave.

Referenced by ata_detect_drive(), ata_select_drive(), ata_setup(), and pio_flush().

◆ ata_setup()

void ata_setup	(	struct ata_drive *	drive,
		uint64_t	lba,
		size_t	count )

Writes the registers of a command on count sectors from lba: the drive, the address and the count.

The command itself is sent after.

Parameters

drive	the drive
lba	the first sector
count	how many sectors

Definition at line 155 of file ata.c.

References ATA_MODE_LBA48, ATA_REG_ERROR, ATA_REG_HDDEVSEL, ATA_REG_LBA0, ATA_REG_LBA1, ATA_REG_LBA2, ATA_REG_SECCOUNT0, ata_select_drive(), ata_setup(), ata_drive::base, io_out8(), ata_drive::mode, and ata_drive::slave.

Referenced by ata_setup(), dma_transfer(), pio_read_sectors(), and pio_write_sectors().

◆ ata_sync()

int ata_sync ( void )

static

Has every drive write what its cache holds to the disk, for sync().

Returns 0, or -EIO if a drive failed.

Definition at line 428 of file ata.c.

References ata_sync(), ata_drive::channel, channel_acquire(), channel_release(), drives, and flush().

Referenced by ata_sync().

◆ ata_write()

ssize_t ata_write	(	struct devid *	dd,
		off_t	offset,
		size_t	size,
		void *	buf )

static

Writes sectors of a partition, from sector offset on, through the block cache.

Returns how many were written (none past the partition's end: -ENOSPC), or a negative errno.

Definition at line 287 of file ata.c.

References ata_locate(), ata_write(), blkcache_write(), drive_write(), and MIN.

Referenced by ata_write().

◆ channel_acquire()

void channel_acquire ( struct ata_channel * ch )

static

Takes a channel for one command, waiting while another runs (a DMA request sleeps).

Before there are processes, nothing else runs. A signal doesn't end the wait: a transfer is never left halfway.

Definition at line 41 of file ata.c.

References ata_channel::busy, channel_acquire(), curthread, sched_running, ata_channel::wait, and waitq_sleep_unint().

Referenced by ata_locate(), ata_sync(), channel_acquire(), drive_read(), and drive_write().

◆ channel_release()

void channel_release ( struct ata_channel * ch )

static

Gives a channel back, and wakes up the requests waiting for it.

Definition at line 50 of file ata.c.

References ata_channel::busy, channel_release(), ata_channel::wait, and waitq_wakeup_nopoll().

Referenced by ata_locate(), ata_sync(), channel_release(), drive_read(), and drive_write().

◆ drive_read()

ssize_t drive_read	(	void *	_drive,
		uint64_t	lba,
		size_t	count,
		void *	buf )

static

Reads sectors from a drive, for the block cache: the channel is held for the command only, and the buffer is the cache's.

Definition at line 58 of file ata.c.

References ata_drive::channel, channel_acquire(), channel_release(), drive_read(), and ata_drive::read.

Referenced by ata_read(), and drive_read().

◆ drive_write()

ssize_t drive_write	(	void *	_drive,
		uint64_t	lba,
		size_t	count,
		void *	buf )

static

Writes sectors to a drive, for the block cache.

Definition at line 70 of file ata.c.

References ata_drive::channel, channel_acquire(), channel_release(), drive_write(), and ata_drive::write.

Referenced by ata_write(), and drive_write().

Variable Documentation

◆ atadev

struct dev atadev

Initial value:

         = {
    .name  = "ata",
    .probe = ata_probe,
    .bread  = ata_read,
    .bwrite = ata_write,
    .getbs = ata_getbs,
    .sync  = ata_sync,
 
    .fops = {
        .open  = posix_file_open,
        .read  = posix_file_read,
        .write = posix_file_write,
    },
}

Definition at line 592 of file ata.c.

Referenced by ata_probe().

◆ channels

struct ata_channel channels[2]

static

Definition at line 36 of file ata.c.

Referenced by ata_probe().

◆ drives

struct ata_drive drives[4]

static

Definition at line 35 of file ata.c.

Referenced by ata_locate(), ata_probe(), and ata_sync().

◆ last_selected_drive

struct ata_drive* last_selected_drive = NULL

static

Definition at line 89 of file ata.c.

Referenced by ata_reset(), and ata_select_drive().

◆ last_selected_mode

uint32_t last_selected_mode = -1

static

Definition at line 90 of file ata.c.

Referenced by ata_reset(), and ata_select_drive().

Macros

Functions

Variables

Detailed Description

Macro Definition Documentation

◆ BLOCK_SIZE

Function Documentation

◆ ata_detect_drive()

◆ ata_drive_present()

◆ ata_getbs()

◆ ata_irq()

◆ ata_locate()

◆ ata_partition()

◆ ata_probe()

◆ ata_read()

◆ ata_reset()

◆ ata_select_drive()

◆ ata_setup()

◆ ata_sync()

◆ ata_write()

◆ channel_acquire()

◆ channel_release()

◆ drive_read()

◆ drive_write()

Variable Documentation

◆ atadev

◆ channels

◆ drives

◆ last_selected_drive

◆ last_selected_mode