net/ism: Add new API for client registration

Add a new API that allows other drivers to concurrently access ISM devices.
To do so, we introduce a new API that allows other modules to register for
ISM device usage. Furthermore, we move the GID to struct ism, where it
belongs conceptually, and rename and relocate struct smcd_event to struct
ism_event.
This is the first part of a bigger overhaul of the interfaces between SMC
and ISM.

Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Jan Karcher <jaka@linux.ibm.com>
Signed-off-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Stefan Raspl 2023-01-23 19:17:48 +01:00 committed by David S. Miller
parent 1baedb13f1
commit 89e7d2ba61
5 changed files with 236 additions and 36 deletions

View File

@ -16,7 +16,6 @@
*/
#define ISM_DMB_WORD_OFFSET 1
#define ISM_DMB_BIT_OFFSET (ISM_DMB_WORD_OFFSET * 32)
#define ISM_NR_DMBS 1920
#define ISM_IDENT_MASK 0x00FFFF
#define ISM_REG_SBA 0x1
@ -178,7 +177,7 @@ struct ism_eq_header {
struct ism_eq {
struct ism_eq_header header;
struct smcd_event entry[15];
struct ism_event entry[15];
};
struct ism_sba {
@ -190,21 +189,6 @@ struct ism_sba {
u16 dmbe_mask[ISM_NR_DMBS];
};
struct ism_dev {
spinlock_t lock;
struct pci_dev *pdev;
struct smcd_dev *smcd;
struct ism_sba *sba;
dma_addr_t sba_dma_addr;
DECLARE_BITMAP(sba_bitmap, ISM_NR_DMBS);
struct ism_eq *ieq;
dma_addr_t ieq_dma_addr;
int ieq_idx;
};
#define ISM_CREATE_REQ(dmb, idx, sf, offset) \
((dmb) | (idx) << 24 | (sf) << 23 | (offset))

View File

@ -15,9 +15,6 @@
#include <linux/err.h>
#include <linux/ctype.h>
#include <linux/processor.h>
#include <net/smc.h>
#include <asm/debug.h>
#include "ism.h"
@ -34,6 +31,84 @@ static const struct pci_device_id ism_device_table[] = {
MODULE_DEVICE_TABLE(pci, ism_device_table);
static debug_info_t *ism_debug_info;
static const struct smcd_ops ism_ops;
#define NO_CLIENT 0xff /* must be >= MAX_CLIENTS */
static struct ism_client *clients[MAX_CLIENTS]; /* use an array rather than */
/* a list for fast mapping */
static u8 max_client;
static DEFINE_SPINLOCK(clients_lock);
struct ism_dev_list {
struct list_head list;
struct mutex mutex; /* protects ism device list */
};
static struct ism_dev_list ism_dev_list = {
.list = LIST_HEAD_INIT(ism_dev_list.list),
.mutex = __MUTEX_INITIALIZER(ism_dev_list.mutex),
};
int ism_register_client(struct ism_client *client)
{
struct ism_dev *ism;
unsigned long flags;
int i, rc = -ENOSPC;
mutex_lock(&ism_dev_list.mutex);
spin_lock_irqsave(&clients_lock, flags);
for (i = 0; i < MAX_CLIENTS; ++i) {
if (!clients[i]) {
clients[i] = client;
client->id = i;
if (i == max_client)
max_client++;
rc = 0;
break;
}
}
spin_unlock_irqrestore(&clients_lock, flags);
if (i < MAX_CLIENTS) {
/* initialize with all devices that we got so far */
list_for_each_entry(ism, &ism_dev_list.list, list) {
ism->priv[i] = NULL;
client->add(ism);
}
}
mutex_unlock(&ism_dev_list.mutex);
return rc;
}
EXPORT_SYMBOL_GPL(ism_register_client);
int ism_unregister_client(struct ism_client *client)
{
struct ism_dev *ism;
unsigned long flags;
int rc = 0;
mutex_lock(&ism_dev_list.mutex);
spin_lock_irqsave(&clients_lock, flags);
clients[client->id] = NULL;
if (client->id + 1 == max_client)
max_client--;
spin_unlock_irqrestore(&clients_lock, flags);
list_for_each_entry(ism, &ism_dev_list.list, list) {
for (int i = 0; i < ISM_NR_DMBS; ++i) {
if (ism->sba_client_arr[i] == client->id) {
pr_err("%s: attempt to unregister client '%s'"
"with registered dmb(s)\n", __func__,
client->name);
rc = -EBUSY;
goto out;
}
}
}
out:
mutex_unlock(&ism_dev_list.mutex);
return rc;
}
EXPORT_SYMBOL_GPL(ism_unregister_client);
static int ism_cmd(struct ism_dev *ism, void *cmd)
{
@ -193,7 +268,7 @@ static int ism_read_local_gid(struct ism_dev *ism)
if (ret)
goto out;
ism->smcd->local_gid = cmd.response.gid;
ism->local_gid = cmd.response.gid;
out:
return ret;
}
@ -437,7 +512,8 @@ static u16 ism_get_chid(struct smcd_dev *smcd)
static void ism_handle_event(struct ism_dev *ism)
{
struct smcd_event *entry;
struct ism_event *entry;
int i;
while ((ism->ieq_idx + 1) != READ_ONCE(ism->ieq->header.idx)) {
if (++(ism->ieq_idx) == ARRAY_SIZE(ism->ieq->entry))
@ -445,13 +521,18 @@ static void ism_handle_event(struct ism_dev *ism)
entry = &ism->ieq->entry[ism->ieq_idx];
debug_event(ism_debug_info, 2, entry, sizeof(*entry));
smcd_handle_event(ism->smcd, entry);
spin_lock(&clients_lock);
for (i = 0; i < max_client; ++i)
if (clients[i])
clients[i]->handle_event(ism, entry);
spin_unlock(&clients_lock);
}
}
static irqreturn_t ism_handle_irq(int irq, void *data)
{
struct ism_dev *ism = data;
struct ism_client *clt;
unsigned long bit, end;
unsigned long *bv;
u16 dmbemask;
@ -471,7 +552,8 @@ static irqreturn_t ism_handle_irq(int irq, void *data)
dmbemask = ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET];
ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET] = 0;
barrier();
smcd_handle_irq(ism->smcd, bit + ISM_DMB_BIT_OFFSET, dmbemask);
clt = clients[ism->sba_client_arr[bit]];
clt->handle_irq(ism, bit + ISM_DMB_BIT_OFFSET, dmbemask);
}
if (ism->sba->e) {
@ -497,10 +579,21 @@ static const struct smcd_ops ism_ops = {
.get_chid = ism_get_chid,
};
static void ism_dev_add_work_func(struct work_struct *work)
{
struct ism_client *client = container_of(work, struct ism_client,
add_work);
client->add(client->tgt_ism);
atomic_dec(&client->tgt_ism->add_dev_cnt);
wake_up(&client->tgt_ism->waitq);
}
static int ism_dev_init(struct ism_dev *ism)
{
struct pci_dev *pdev = ism->pdev;
int ret;
unsigned long flags;
int i, ret;
ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
if (ret <= 0)
@ -527,6 +620,28 @@ static int ism_dev_init(struct ism_dev *ism)
/* hardware is V2 capable */
ism_create_system_eid();
init_waitqueue_head(&ism->waitq);
atomic_set(&ism->free_clients_cnt, 0);
atomic_set(&ism->add_dev_cnt, 0);
wait_event(ism->waitq, !atomic_read(&ism->add_dev_cnt));
spin_lock_irqsave(&clients_lock, flags);
for (i = 0; i < max_client; ++i)
if (clients[i]) {
INIT_WORK(&clients[i]->add_work,
ism_dev_add_work_func);
clients[i]->tgt_ism = ism;
atomic_inc(&ism->add_dev_cnt);
schedule_work(&clients[i]->add_work);
}
spin_unlock_irqrestore(&clients_lock, flags);
wait_event(ism->waitq, !atomic_read(&ism->add_dev_cnt));
mutex_lock(&ism_dev_list.mutex);
list_add(&ism->list, &ism_dev_list.list);
mutex_unlock(&ism_dev_list.mutex);
ret = smcd_register_dev(ism->smcd);
if (ret)
goto unreg_ieq;
@ -602,9 +717,36 @@ err:
return ret;
}
static void ism_dev_remove_work_func(struct work_struct *work)
{
struct ism_client *client = container_of(work, struct ism_client,
remove_work);
client->remove(client->tgt_ism);
atomic_dec(&client->tgt_ism->free_clients_cnt);
wake_up(&client->tgt_ism->waitq);
}
/* Callers must hold ism_dev_list.mutex */
static void ism_dev_exit(struct ism_dev *ism)
{
struct pci_dev *pdev = ism->pdev;
unsigned long flags;
int i;
wait_event(ism->waitq, !atomic_read(&ism->free_clients_cnt));
spin_lock_irqsave(&clients_lock, flags);
for (i = 0; i < max_client; ++i)
if (clients[i]) {
INIT_WORK(&clients[i]->remove_work,
ism_dev_remove_work_func);
clients[i]->tgt_ism = ism;
atomic_inc(&ism->free_clients_cnt);
schedule_work(&clients[i]->remove_work);
}
spin_unlock_irqrestore(&clients_lock, flags);
wait_event(ism->waitq, !atomic_read(&ism->free_clients_cnt));
smcd_unregister_dev(ism->smcd);
if (SYSTEM_EID.serial_number[0] != '0' ||
@ -614,18 +756,22 @@ static void ism_dev_exit(struct ism_dev *ism)
unregister_sba(ism);
free_irq(pci_irq_vector(pdev, 0), ism);
pci_free_irq_vectors(pdev);
list_del_init(&ism->list);
}
static void ism_remove(struct pci_dev *pdev)
{
struct ism_dev *ism = dev_get_drvdata(&pdev->dev);
mutex_lock(&ism_dev_list.mutex);
ism_dev_exit(ism);
mutex_unlock(&ism_dev_list.mutex);
smcd_free_dev(ism->smcd);
pci_clear_master(pdev);
pci_release_mem_regions(pdev);
pci_disable_device(pdev);
device_del(&ism->dev);
dev_set_drvdata(&pdev->dev, NULL);
kfree(ism);
}
@ -645,6 +791,8 @@ static int __init ism_init(void)
if (!ism_debug_info)
return -ENODEV;
memset(clients, 0, sizeof(clients));
max_client = 0;
debug_register_view(ism_debug_info, &debug_hex_ascii_view);
ret = pci_register_driver(&ism_driver);
if (ret)
@ -655,6 +803,14 @@ static int __init ism_init(void)
static void __exit ism_exit(void)
{
struct ism_dev *ism;
mutex_lock(&ism_dev_list.mutex);
list_for_each_entry(ism, &ism_dev_list.list, list) {
ism_dev_exit(ism);
}
mutex_unlock(&ism_dev_list.mutex);
pci_unregister_driver(&ism_driver);
debug_unregister(ism_debug_info);
}

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@ -9,6 +9,8 @@
#ifndef _ISM_H
#define _ISM_H
#include <linux/workqueue.h>
struct ism_dmb {
u64 dmb_tok;
u64 rgid;
@ -20,4 +22,69 @@ struct ism_dmb {
dma_addr_t dma_addr;
};
/* Unless we gain unexpected popularity, this limit should hold for a while */
#define MAX_CLIENTS 8
#define ISM_NR_DMBS 1920
struct ism_dev {
spinlock_t lock; /* protects the ism device */
struct list_head list;
struct pci_dev *pdev;
struct smcd_dev *smcd;
struct ism_sba *sba;
dma_addr_t sba_dma_addr;
DECLARE_BITMAP(sba_bitmap, ISM_NR_DMBS);
u8 *sba_client_arr; /* entries are indices into 'clients' array */
void *priv[MAX_CLIENTS];
struct ism_eq *ieq;
dma_addr_t ieq_dma_addr;
struct device dev;
u64 local_gid;
int ieq_idx;
atomic_t free_clients_cnt;
atomic_t add_dev_cnt;
wait_queue_head_t waitq;
};
struct ism_event {
u32 type;
u32 code;
u64 tok;
u64 time;
u64 info;
};
struct ism_client {
const char *name;
void (*add)(struct ism_dev *dev);
void (*remove)(struct ism_dev *dev);
void (*handle_event)(struct ism_dev *dev, struct ism_event *event);
/* Parameter dmbemask contains a bit vector with updated DMBEs, if sent
* via ism_move_data(). Callback function must handle all active bits
* indicated by dmbemask.
*/
void (*handle_irq)(struct ism_dev *dev, unsigned int bit, u16 dmbemask);
/* Private area - don't touch! */
struct work_struct remove_work;
struct work_struct add_work;
struct ism_dev *tgt_ism;
u8 id;
};
int ism_register_client(struct ism_client *client);
int ism_unregister_client(struct ism_client *client);
static inline void *ism_get_priv(struct ism_dev *dev,
struct ism_client *client) {
return dev->priv[client->id];
}
static inline void ism_set_priv(struct ism_dev *dev, struct ism_client *client,
void *priv) {
dev->priv[client->id] = priv;
}
#endif /* _ISM_H */

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@ -15,6 +15,7 @@
#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/wait.h>
#include "linux/ism.h"
struct sock;
@ -48,14 +49,6 @@ struct smcd_dmb {
#define ISM_ERROR 0xFFFF
struct smcd_event {
u32 type;
u32 code;
u64 tok;
u64 time;
u64 info;
};
struct smcd_dev;
struct smcd_ops {
@ -100,6 +93,6 @@ struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
int smcd_register_dev(struct smcd_dev *smcd);
void smcd_unregister_dev(struct smcd_dev *smcd);
void smcd_free_dev(struct smcd_dev *smcd);
void smcd_handle_event(struct smcd_dev *dev, struct smcd_event *event);
void smcd_handle_event(struct smcd_dev *dev, struct ism_event *event);
void smcd_handle_irq(struct smcd_dev *dev, unsigned int bit, u16 dmbemask);
#endif /* _SMC_H */

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@ -296,7 +296,7 @@ int smcd_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb)
struct smc_ism_event_work {
struct work_struct work;
struct smcd_dev *smcd;
struct smcd_event event;
struct ism_event event;
};
#define ISM_EVENT_REQUEST 0x0001
@ -490,7 +490,7 @@ EXPORT_SYMBOL_GPL(smcd_free_dev);
* Context:
* - Function called in IRQ context from ISM device driver event handler.
*/
void smcd_handle_event(struct smcd_dev *smcd, struct smcd_event *event)
void smcd_handle_event(struct smcd_dev *smcd, struct ism_event *event)
{
struct smc_ism_event_work *wrk;