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path: root/drivers/firewire/core-card.c
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Diffstat (limited to 'drivers/firewire/core-card.c')
-rw-r--r--drivers/firewire/core-card.c41
1 files changed, 28 insertions, 13 deletions
diff --git a/drivers/firewire/core-card.c b/drivers/firewire/core-card.c
index 7083bcc1b9c..5045156c531 100644
--- a/drivers/firewire/core-card.c
+++ b/drivers/firewire/core-card.c
@@ -57,6 +57,8 @@ static LIST_HEAD(descriptor_list);
static int descriptor_count;
static __be32 tmp_config_rom[256];
+/* ROM header, bus info block, root dir header, capabilities = 7 quadlets */
+static size_t config_rom_length = 1 + 4 + 1 + 1;
#define BIB_CRC(v) ((v) << 0)
#define BIB_CRC_LENGTH(v) ((v) << 16)
@@ -73,7 +75,7 @@ static __be32 tmp_config_rom[256];
#define BIB_CMC ((1) << 30)
#define BIB_IMC ((1) << 31)
-static size_t generate_config_rom(struct fw_card *card, __be32 *config_rom)
+static void generate_config_rom(struct fw_card *card, __be32 *config_rom)
{
struct fw_descriptor *desc;
int i, j, k, length;
@@ -130,23 +132,30 @@ static size_t generate_config_rom(struct fw_card *card, __be32 *config_rom)
for (i = 0; i < j; i += length + 1)
length = fw_compute_block_crc(config_rom + i);
- return j;
+ WARN_ON(j != config_rom_length);
}
static void update_config_roms(void)
{
struct fw_card *card;
- size_t length;
list_for_each_entry (card, &card_list, link) {
- length = generate_config_rom(card, tmp_config_rom);
- card->driver->set_config_rom(card, tmp_config_rom, length);
+ generate_config_rom(card, tmp_config_rom);
+ card->driver->set_config_rom(card, tmp_config_rom,
+ config_rom_length);
}
}
+static size_t required_space(struct fw_descriptor *desc)
+{
+ /* descriptor + entry into root dir + optional immediate entry */
+ return desc->length + 1 + (desc->immediate > 0 ? 1 : 0);
+}
+
int fw_core_add_descriptor(struct fw_descriptor *desc)
{
size_t i;
+ int ret;
/*
* Check descriptor is valid; the length of all blocks in the
@@ -162,15 +171,21 @@ int fw_core_add_descriptor(struct fw_descriptor *desc)
mutex_lock(&card_mutex);
- list_add_tail(&desc->link, &descriptor_list);
- descriptor_count++;
- if (desc->immediate > 0)
+ if (config_rom_length + required_space(desc) > 256) {
+ ret = -EBUSY;
+ } else {
+ list_add_tail(&desc->link, &descriptor_list);
+ config_rom_length += required_space(desc);
descriptor_count++;
- update_config_roms();
+ if (desc->immediate > 0)
+ descriptor_count++;
+ update_config_roms();
+ ret = 0;
+ }
mutex_unlock(&card_mutex);
- return 0;
+ return ret;
}
EXPORT_SYMBOL(fw_core_add_descriptor);
@@ -179,6 +194,7 @@ void fw_core_remove_descriptor(struct fw_descriptor *desc)
mutex_lock(&card_mutex);
list_del(&desc->link);
+ config_rom_length -= required_space(desc);
descriptor_count--;
if (desc->immediate > 0)
descriptor_count--;
@@ -428,7 +444,6 @@ EXPORT_SYMBOL(fw_card_initialize);
int fw_card_add(struct fw_card *card,
u32 max_receive, u32 link_speed, u64 guid)
{
- size_t length;
int ret;
card->max_receive = max_receive;
@@ -437,8 +452,8 @@ int fw_card_add(struct fw_card *card,
mutex_lock(&card_mutex);
- length = generate_config_rom(card, tmp_config_rom);
- ret = card->driver->enable(card, tmp_config_rom, length);
+ generate_config_rom(card, tmp_config_rom);
+ ret = card->driver->enable(card, tmp_config_rom, config_rom_length);
if (ret == 0)
list_add_tail(&card->link, &card_list);