firewire: reread config ROM when device reset the bus

When a device changes its configuration ROM, it announces this with a
bus reset.  firewire-core has to check which node initiated a bus reset
and whether any unit directories went away or were added on this node.

Tested with an IOI FWB-IDE01AB which has its link-on bit set if bus
power is available but does not respond to ROM read requests if self
power is off.  This implements
  - recognition of the units if self power is switched on after fw-core
    gave up the initial attempt to read the config ROM,
  - shutdown of the units when self power is switched off.

Also tested with a second PC running Linux/ieee1394.  When the eth1394
driver is inserted and removed on that node, fw-core now notices the
addition and removal of the IPv4 unit on the ieee1394 node.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This commit is contained in:
Stefan Richter 2008-03-24 20:54:28 +01:00
parent 1dadff71d6
commit c9755e14a0
7 changed files with 223 additions and 47 deletions

View File

@ -331,7 +331,7 @@ fw_card_bm_work(struct work_struct *work)
*/
spin_unlock_irqrestore(&card->lock, flags);
goto out;
} else if (root_device->config_rom[2] & BIB_CMC) {
} else if (root_device->cmc) {
/*
* FIXME: I suppose we should set the cmstr bit in the
* STATE_CLEAR register of this node, as described in

View File

@ -269,21 +269,28 @@ static int ioctl_get_info(struct client *client, void *buffer)
{
struct fw_cdev_get_info *get_info = buffer;
struct fw_cdev_event_bus_reset bus_reset;
unsigned long ret = 0;
client->version = get_info->version;
get_info->version = FW_CDEV_VERSION;
down_read(&fw_device_rwsem);
if (get_info->rom != 0) {
void __user *uptr = u64_to_uptr(get_info->rom);
size_t want = get_info->rom_length;
size_t have = client->device->config_rom_length * 4;
if (copy_to_user(uptr, client->device->config_rom,
min(want, have)))
return -EFAULT;
ret = copy_to_user(uptr, client->device->config_rom,
min(want, have));
}
get_info->rom_length = client->device->config_rom_length * 4;
up_read(&fw_device_rwsem);
if (ret != 0)
return -EFAULT;
client->bus_reset_closure = get_info->bus_reset_closure;
if (get_info->bus_reset != 0) {
void __user *uptr = u64_to_uptr(get_info->bus_reset);

View File

@ -25,7 +25,7 @@
#include <linux/device.h>
#include <linux/delay.h>
#include <linux/idr.h>
#include <linux/rwsem.h>
#include <linux/string.h>
#include <asm/semaphore.h>
#include <asm/system.h>
#include <linux/ctype.h>
@ -160,9 +160,9 @@ static void fw_device_release(struct device *dev)
* Take the card lock so we don't set this to NULL while a
* FW_NODE_UPDATED callback is being handled.
*/
spin_lock_irqsave(&device->card->lock, flags);
spin_lock_irqsave(&card->lock, flags);
device->node->data = NULL;
spin_unlock_irqrestore(&device->card->lock, flags);
spin_unlock_irqrestore(&card->lock, flags);
fw_node_put(device->node);
kfree(device->config_rom);
@ -195,7 +195,9 @@ show_immediate(struct device *dev, struct device_attribute *dattr, char *buf)
container_of(dattr, struct config_rom_attribute, attr);
struct fw_csr_iterator ci;
u32 *dir;
int key, value;
int key, value, ret = -ENOENT;
down_read(&fw_device_rwsem);
if (is_fw_unit(dev))
dir = fw_unit(dev)->directory;
@ -204,11 +206,15 @@ show_immediate(struct device *dev, struct device_attribute *dattr, char *buf)
fw_csr_iterator_init(&ci, dir);
while (fw_csr_iterator_next(&ci, &key, &value))
if (attr->key == key)
return snprintf(buf, buf ? PAGE_SIZE : 0,
"0x%06x\n", value);
if (attr->key == key) {
ret = snprintf(buf, buf ? PAGE_SIZE : 0,
"0x%06x\n", value);
break;
}
return -ENOENT;
up_read(&fw_device_rwsem);
return ret;
}
#define IMMEDIATE_ATTR(name, key) \
@ -221,9 +227,11 @@ show_text_leaf(struct device *dev, struct device_attribute *dattr, char *buf)
container_of(dattr, struct config_rom_attribute, attr);
struct fw_csr_iterator ci;
u32 *dir, *block = NULL, *p, *end;
int length, key, value, last_key = 0;
int length, key, value, last_key = 0, ret = -ENOENT;
char *b;
down_read(&fw_device_rwsem);
if (is_fw_unit(dev))
dir = fw_unit(dev)->directory;
else
@ -238,18 +246,20 @@ show_text_leaf(struct device *dev, struct device_attribute *dattr, char *buf)
}
if (block == NULL)
return -ENOENT;
goto out;
length = min(block[0] >> 16, 256U);
if (length < 3)
return -ENOENT;
goto out;
if (block[1] != 0 || block[2] != 0)
/* Unknown encoding. */
return -ENOENT;
goto out;
if (buf == NULL)
return length * 4;
if (buf == NULL) {
ret = length * 4;
goto out;
}
b = buf;
end = &block[length + 1];
@ -259,8 +269,11 @@ show_text_leaf(struct device *dev, struct device_attribute *dattr, char *buf)
/* Strip trailing whitespace and add newline. */
while (b--, (isspace(*b) || *b == '\0') && b > buf);
strcpy(b + 1, "\n");
ret = b + 2 - buf;
out:
up_read(&fw_device_rwsem);
return b + 2 - buf;
return ret;
}
#define TEXT_LEAF_ATTR(name, key) \
@ -337,19 +350,28 @@ static ssize_t
config_rom_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct fw_device *device = fw_device(dev);
size_t length;
memcpy(buf, device->config_rom, device->config_rom_length * 4);
down_read(&fw_device_rwsem);
length = device->config_rom_length * 4;
memcpy(buf, device->config_rom, length);
up_read(&fw_device_rwsem);
return device->config_rom_length * 4;
return length;
}
static ssize_t
guid_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct fw_device *device = fw_device(dev);
int ret;
return snprintf(buf, PAGE_SIZE, "0x%08x%08x\n",
device->config_rom[3], device->config_rom[4]);
down_read(&fw_device_rwsem);
ret = snprintf(buf, PAGE_SIZE, "0x%08x%08x\n",
device->config_rom[3], device->config_rom[4]);
up_read(&fw_device_rwsem);
return ret;
}
static struct device_attribute fw_device_attributes[] = {
@ -412,7 +434,7 @@ read_rom(struct fw_device *device, int generation, int index, u32 *data)
*/
static int read_bus_info_block(struct fw_device *device, int generation)
{
u32 *rom, *stack;
u32 *rom, *stack, *old_rom, *new_rom;
u32 sp, key;
int i, end, length, ret = -1;
@ -527,12 +549,19 @@ static int read_bus_info_block(struct fw_device *device, int generation)
length = i;
}
device->config_rom = kmalloc(length * 4, GFP_KERNEL);
if (device->config_rom == NULL)
old_rom = device->config_rom;
new_rom = kmemdup(rom, length * 4, GFP_KERNEL);
if (new_rom == NULL)
goto out;
memcpy(device->config_rom, rom, length * 4);
down_write(&fw_device_rwsem);
device->config_rom = new_rom;
device->config_rom_length = length;
up_write(&fw_device_rwsem);
kfree(old_rom);
ret = 0;
device->cmc = rom[2] & 1 << 30;
out:
kfree(rom);
@ -605,7 +634,14 @@ static int shutdown_unit(struct device *device, void *data)
return 0;
}
static DECLARE_RWSEM(idr_rwsem);
/*
* fw_device_rwsem acts as dual purpose mutex:
* - serializes accesses to fw_device_idr,
* - serializes accesses to fw_device.config_rom/.config_rom_length and
* fw_unit.directory, unless those accesses happen at safe occasions
*/
DECLARE_RWSEM(fw_device_rwsem);
static DEFINE_IDR(fw_device_idr);
int fw_cdev_major;
@ -613,11 +649,11 @@ struct fw_device *fw_device_get_by_devt(dev_t devt)
{
struct fw_device *device;
down_read(&idr_rwsem);
down_read(&fw_device_rwsem);
device = idr_find(&fw_device_idr, MINOR(devt));
if (device)
fw_device_get(device);
up_read(&idr_rwsem);
up_read(&fw_device_rwsem);
return device;
}
@ -632,9 +668,9 @@ static void fw_device_shutdown(struct work_struct *work)
device_for_each_child(&device->device, NULL, shutdown_unit);
device_unregister(&device->device);
down_write(&idr_rwsem);
down_write(&fw_device_rwsem);
idr_remove(&fw_device_idr, minor);
up_write(&idr_rwsem);
up_write(&fw_device_rwsem);
fw_device_put(device);
}
@ -687,10 +723,10 @@ static void fw_device_init(struct work_struct *work)
err = -ENOMEM;
fw_device_get(device);
down_write(&idr_rwsem);
down_write(&fw_device_rwsem);
if (idr_pre_get(&fw_device_idr, GFP_KERNEL))
err = idr_get_new(&fw_device_idr, device, &minor);
up_write(&idr_rwsem);
up_write(&fw_device_rwsem);
if (err < 0)
goto error;
@ -724,7 +760,7 @@ static void fw_device_init(struct work_struct *work)
if (atomic_cmpxchg(&device->state,
FW_DEVICE_INITIALIZING,
FW_DEVICE_RUNNING) == FW_DEVICE_SHUTDOWN) {
fw_device_shutdown(&device->work.work);
fw_device_shutdown(work);
} else {
if (device->config_rom_retries)
fw_notify("created device %s: GUID %08x%08x, S%d00, "
@ -738,6 +774,7 @@ static void fw_device_init(struct work_struct *work)
device->device.bus_id,
device->config_rom[3], device->config_rom[4],
1 << device->max_speed);
device->config_rom_retries = 0;
}
/*
@ -752,9 +789,9 @@ static void fw_device_init(struct work_struct *work)
return;
error_with_cdev:
down_write(&idr_rwsem);
down_write(&fw_device_rwsem);
idr_remove(&fw_device_idr, minor);
up_write(&idr_rwsem);
up_write(&fw_device_rwsem);
error:
fw_device_put(device); /* fw_device_idr's reference */
@ -784,6 +821,106 @@ static void fw_device_update(struct work_struct *work)
device_for_each_child(&device->device, NULL, update_unit);
}
enum {
REREAD_BIB_ERROR,
REREAD_BIB_GONE,
REREAD_BIB_UNCHANGED,
REREAD_BIB_CHANGED,
};
/* Reread and compare bus info block and header of root directory */
static int reread_bus_info_block(struct fw_device *device, int generation)
{
u32 q;
int i;
for (i = 0; i < 6; i++) {
if (read_rom(device, generation, i, &q) != RCODE_COMPLETE)
return REREAD_BIB_ERROR;
if (i == 0 && q == 0)
return REREAD_BIB_GONE;
if (i > device->config_rom_length || q != device->config_rom[i])
return REREAD_BIB_CHANGED;
}
return REREAD_BIB_UNCHANGED;
}
static void fw_device_refresh(struct work_struct *work)
{
struct fw_device *device =
container_of(work, struct fw_device, work.work);
struct fw_card *card = device->card;
int node_id = device->node_id;
switch (reread_bus_info_block(device, device->generation)) {
case REREAD_BIB_ERROR:
if (device->config_rom_retries < MAX_RETRIES / 2 &&
atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
device->config_rom_retries++;
schedule_delayed_work(&device->work, RETRY_DELAY / 2);
return;
}
goto give_up;
case REREAD_BIB_GONE:
goto gone;
case REREAD_BIB_UNCHANGED:
if (atomic_cmpxchg(&device->state,
FW_DEVICE_INITIALIZING,
FW_DEVICE_RUNNING) == FW_DEVICE_SHUTDOWN)
goto gone;
fw_device_update(work);
device->config_rom_retries = 0;
goto out;
case REREAD_BIB_CHANGED:
break;
}
/*
* Something changed. We keep things simple and don't investigate
* further. We just destroy all previous units and create new ones.
*/
device_for_each_child(&device->device, NULL, shutdown_unit);
if (read_bus_info_block(device, device->generation) < 0) {
if (device->config_rom_retries < MAX_RETRIES &&
atomic_read(&device->state) == FW_DEVICE_INITIALIZING) {
device->config_rom_retries++;
schedule_delayed_work(&device->work, RETRY_DELAY);
return;
}
goto give_up;
}
create_units(device);
if (atomic_cmpxchg(&device->state,
FW_DEVICE_INITIALIZING,
FW_DEVICE_RUNNING) == FW_DEVICE_SHUTDOWN)
goto gone;
fw_notify("refreshed device %s\n", device->device.bus_id);
device->config_rom_retries = 0;
goto out;
give_up:
fw_notify("giving up on refresh of device %s\n", device->device.bus_id);
gone:
atomic_set(&device->state, FW_DEVICE_SHUTDOWN);
fw_device_shutdown(work);
out:
if (node_id == card->root_node->node_id)
schedule_delayed_work(&card->work, 0);
}
void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
{
struct fw_device *device;
@ -793,7 +930,7 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
case FW_NODE_LINK_ON:
if (!node->link_on)
break;
create:
device = kzalloc(sizeof(*device), GFP_ATOMIC);
if (device == NULL)
break;
@ -832,6 +969,23 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
schedule_delayed_work(&device->work, INITIAL_DELAY);
break;
case FW_NODE_INITIATED_RESET:
device = node->data;
if (device == NULL)
goto create;
device->node_id = node->node_id;
smp_wmb(); /* update node_id before generation */
device->generation = card->generation;
if (atomic_cmpxchg(&device->state,
FW_DEVICE_RUNNING,
FW_DEVICE_INITIALIZING) == FW_DEVICE_RUNNING) {
PREPARE_DELAYED_WORK(&device->work, fw_device_refresh);
schedule_delayed_work(&device->work,
node == card->local_node ? 0 : INITIAL_DELAY);
}
break;
case FW_NODE_UPDATED:
if (!node->link_on || node->data == NULL)
break;

View File

@ -21,6 +21,7 @@
#include <linux/fs.h>
#include <linux/cdev.h>
#include <linux/rwsem.h>
#include <asm/atomic.h>
enum fw_device_state {
@ -46,6 +47,11 @@ struct fw_attribute_group {
* fw_device.node_id is guaranteed to be current too.
*
* The same applies to fw_device.card->node_id vs. fw_device.generation.
*
* fw_device.config_rom and fw_device.config_rom_length may be accessed during
* the lifetime of any fw_unit belonging to the fw_device, before device_del()
* was called on the last fw_unit. Alternatively, they may be accessed while
* holding fw_device_rwsem.
*/
struct fw_device {
atomic_t state;
@ -53,6 +59,7 @@ struct fw_device {
int node_id;
int generation;
unsigned max_speed;
bool cmc;
struct fw_card *card;
struct device device;
struct list_head link;
@ -92,8 +99,12 @@ int fw_device_enable_phys_dma(struct fw_device *device);
void fw_device_cdev_update(struct fw_device *device);
void fw_device_cdev_remove(struct fw_device *device);
extern struct rw_semaphore fw_device_rwsem;
extern int fw_cdev_major;
/*
* fw_unit.directory must not be accessed after device_del(&fw_unit.device).
*/
struct fw_unit {
struct device device;
u32 *directory;

View File

@ -153,6 +153,7 @@ struct sbp2_target {
struct list_head lu_list;
u64 management_agent_address;
u64 guid;
int directory_id;
int node_id;
int address_high;
@ -1114,6 +1115,7 @@ static int sbp2_probe(struct device *dev)
kref_init(&tgt->kref);
INIT_LIST_HEAD(&tgt->lu_list);
tgt->bus_id = unit->device.bus_id;
tgt->guid = (u64)device->config_rom[3] << 32 | device->config_rom[4];
if (fw_device_enable_phys_dma(device) < 0)
goto fail_shost_put;
@ -1571,16 +1573,14 @@ sbp2_sysfs_ieee1394_id_show(struct device *dev, struct device_attribute *attr,
{
struct scsi_device *sdev = to_scsi_device(dev);
struct sbp2_logical_unit *lu;
struct fw_device *device;
if (!sdev)
return 0;
lu = sdev->hostdata;
device = fw_device(lu->tgt->unit->device.parent);
return sprintf(buf, "%08x%08x:%06x:%04x\n",
device->config_rom[3], device->config_rom[4],
return sprintf(buf, "%016llx:%06x:%04x\n",
(unsigned long long)lu->tgt->guid,
lu->tgt->directory_id, lu->lun);
}

View File

@ -108,6 +108,7 @@ static struct fw_node *fw_node_create(u32 sid, int port_count, int color)
node->node_id = LOCAL_BUS | SELF_ID_PHY_ID(sid);
node->link_on = SELF_ID_LINK_ON(sid);
node->phy_speed = SELF_ID_PHY_SPEED(sid);
node->initiated_reset = SELF_ID_PHY_INITIATOR(sid);
node->port_count = port_count;
atomic_set(&node->ref_count, 1);
@ -431,6 +432,8 @@ update_tree(struct fw_card *card, struct fw_node *root)
event = FW_NODE_LINK_OFF;
else if (!node0->link_on && node1->link_on)
event = FW_NODE_LINK_ON;
else if (node1->initiated_reset && node1->link_on)
event = FW_NODE_INITIATED_RESET;
else
event = FW_NODE_UPDATED;

View File

@ -20,11 +20,12 @@
#define __fw_topology_h
enum {
FW_NODE_CREATED = 0x00,
FW_NODE_UPDATED = 0x01,
FW_NODE_DESTROYED = 0x02,
FW_NODE_LINK_ON = 0x03,
FW_NODE_LINK_OFF = 0x04,
FW_NODE_CREATED,
FW_NODE_UPDATED,
FW_NODE_DESTROYED,
FW_NODE_LINK_ON,
FW_NODE_LINK_OFF,
FW_NODE_INITIATED_RESET,
};
struct fw_node {