[PATCH 16/18 v2] ibmveth: enable driver for CMO
Robert Jennings
rcj at linux.vnet.ibm.com
Thu Jun 26 06:19:18 EST 2008
Enable ibmveth for Cooperative Memory Overcommitment (CMO). For this driver
it means calculating a desired amount of IO memory based on the current MTU
and updating this value with the bus when MTU changes occur. Because DMA
mappings can fail, we have added a bounce buffer for temporary cases where
the driver can not map IO memory for the buffer pool.
The following changes are made to enable the driver for CMO:
* DMA mapping errors will not result in error messages if entitlement has
been exceeded and resources were not available.
* DMA mapping errors are handled gracefully, ibmveth_replenish_buffer_pool()
is corrected to check the return from dma_map_single and fail gracefully.
* The driver will have a get_io_entitlement function defined to function
in a CMO environment.
* When the MTU is changed, the driver will update the device IO entitlement
Signed-off-by: Robert Jennings <rcj at linux.vnet.ibm.com>
Signed-off-by: Brian King <brking at linux.vnet.ibm.com>
Signed-off-by: Santiago Leon <santil at us.ibm.com>
---
drivers/net/ibmveth.c | 169 ++++++++++++++++++++++++++++++++++++++++----------
drivers/net/ibmveth.h | 5 +
2 files changed, 140 insertions(+), 34 deletions(-)
Index: b/drivers/net/ibmveth.c
===================================================================
--- a/drivers/net/ibmveth.c
+++ b/drivers/net/ibmveth.c
@@ -33,6 +33,7 @@
*/
#include <linux/module.h>
+#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/ioport.h>
@@ -52,7 +53,9 @@
#include <asm/hvcall.h>
#include <asm/atomic.h>
#include <asm/vio.h>
+#include <asm/iommu.h>
#include <asm/uaccess.h>
+#include <asm/firmware.h>
#include <linux/seq_file.h>
#include "ibmveth.h"
@@ -94,8 +97,10 @@ static void ibmveth_proc_register_adapte
static void ibmveth_proc_unregister_adapter(struct ibmveth_adapter *adapter);
static irqreturn_t ibmveth_interrupt(int irq, void *dev_instance);
static void ibmveth_rxq_harvest_buffer(struct ibmveth_adapter *adapter);
+static unsigned long ibmveth_get_io_entitlement(struct vio_dev *vdev);
static struct kobj_type ktype_veth_pool;
+
#ifdef CONFIG_PROC_FS
#define IBMVETH_PROC_DIR "ibmveth"
static struct proc_dir_entry *ibmveth_proc_dir;
@@ -226,16 +231,16 @@ static void ibmveth_replenish_buffer_poo
u32 i;
u32 count = pool->size - atomic_read(&pool->available);
u32 buffers_added = 0;
+ struct sk_buff *skb;
+ unsigned int free_index, index;
+ u64 correlator;
+ unsigned long lpar_rc;
+ dma_addr_t dma_addr;
mb();
for(i = 0; i < count; ++i) {
- struct sk_buff *skb;
- unsigned int free_index, index;
- u64 correlator;
union ibmveth_buf_desc desc;
- unsigned long lpar_rc;
- dma_addr_t dma_addr;
skb = alloc_skb(pool->buff_size, GFP_ATOMIC);
@@ -255,6 +260,9 @@ static void ibmveth_replenish_buffer_poo
dma_addr = dma_map_single(&adapter->vdev->dev, skb->data,
pool->buff_size, DMA_FROM_DEVICE);
+ if (dma_mapping_error(dma_addr))
+ goto failure;
+
pool->free_map[free_index] = IBM_VETH_INVALID_MAP;
pool->dma_addr[index] = dma_addr;
pool->skbuff[index] = skb;
@@ -267,20 +275,9 @@ static void ibmveth_replenish_buffer_poo
lpar_rc = h_add_logical_lan_buffer(adapter->vdev->unit_address, desc.desc);
- if(lpar_rc != H_SUCCESS) {
- pool->free_map[free_index] = index;
- pool->skbuff[index] = NULL;
- if (pool->consumer_index == 0)
- pool->consumer_index = pool->size - 1;
- else
- pool->consumer_index--;
- dma_unmap_single(&adapter->vdev->dev,
- pool->dma_addr[index], pool->buff_size,
- DMA_FROM_DEVICE);
- dev_kfree_skb_any(skb);
- adapter->replenish_add_buff_failure++;
- break;
- } else {
+ if (lpar_rc != H_SUCCESS)
+ goto failure;
+ else {
buffers_added++;
adapter->replenish_add_buff_success++;
}
@@ -288,6 +285,24 @@ static void ibmveth_replenish_buffer_poo
mb();
atomic_add(buffers_added, &(pool->available));
+ return;
+
+failure:
+ pool->free_map[free_index] = index;
+ pool->skbuff[index] = NULL;
+ if (pool->consumer_index == 0)
+ pool->consumer_index = pool->size - 1;
+ else
+ pool->consumer_index--;
+ if (!dma_mapping_error(dma_addr))
+ dma_unmap_single(&adapter->vdev->dev,
+ pool->dma_addr[index], pool->buff_size,
+ DMA_FROM_DEVICE);
+ dev_kfree_skb_any(skb);
+ adapter->replenish_add_buff_failure++;
+
+ mb();
+ atomic_add(buffers_added, &(pool->available));
}
/* replenish routine */
@@ -297,7 +312,7 @@ static void ibmveth_replenish_task(struc
adapter->replenish_task_cycles++;
- for(i = 0; i < IbmVethNumBufferPools; i++)
+ for (i = (IbmVethNumBufferPools - 1); i >= 0; i--)
if(adapter->rx_buff_pool[i].active)
ibmveth_replenish_buffer_pool(adapter,
&adapter->rx_buff_pool[i]);
@@ -472,6 +487,18 @@ static void ibmveth_cleanup(struct ibmve
if (adapter->rx_buff_pool[i].active)
ibmveth_free_buffer_pool(adapter,
&adapter->rx_buff_pool[i]);
+
+ if (adapter->bounce_buffer != NULL) {
+ if (!dma_mapping_error(adapter->bounce_buffer_dma)) {
+ dma_unmap_single(&adapter->vdev->dev,
+ adapter->bounce_buffer_dma,
+ adapter->netdev->mtu + IBMVETH_BUFF_OH,
+ DMA_BIDIRECTIONAL);
+ adapter->bounce_buffer_dma = DMA_ERROR_CODE;
+ }
+ kfree(adapter->bounce_buffer);
+ adapter->bounce_buffer = NULL;
+ }
}
static int ibmveth_register_logical_lan(struct ibmveth_adapter *adapter,
@@ -607,6 +634,24 @@ static int ibmveth_open(struct net_devic
return rc;
}
+ adapter->bounce_buffer =
+ kmalloc(netdev->mtu + IBMVETH_BUFF_OH, GFP_KERNEL);
+ if (!adapter->bounce_buffer) {
+ ibmveth_error_printk("unable to allocate bounce buffer\n");
+ ibmveth_cleanup(adapter);
+ napi_disable(&adapter->napi);
+ return -ENOMEM;
+ }
+ adapter->bounce_buffer_dma =
+ dma_map_single(&adapter->vdev->dev, adapter->bounce_buffer,
+ netdev->mtu + IBMVETH_BUFF_OH, DMA_BIDIRECTIONAL);
+ if (dma_mapping_error(adapter->bounce_buffer_dma)) {
+ ibmveth_error_printk("unable to map bounce buffer\n");
+ ibmveth_cleanup(adapter);
+ napi_disable(&adapter->napi);
+ return -ENOMEM;
+ }
+
ibmveth_debug_printk("initial replenish cycle\n");
ibmveth_interrupt(netdev->irq, netdev);
@@ -853,10 +898,12 @@ static int ibmveth_start_xmit(struct sk_
unsigned int tx_packets = 0;
unsigned int tx_send_failed = 0;
unsigned int tx_map_failed = 0;
+ int used_bounce = 0;
+ unsigned long data_dma_addr;
desc.fields.flags_len = IBMVETH_BUF_VALID | skb->len;
- desc.fields.address = dma_map_single(&adapter->vdev->dev, skb->data,
- skb->len, DMA_TO_DEVICE);
+ data_dma_addr = dma_map_single(&adapter->vdev->dev, skb->data,
+ skb->len, DMA_TO_DEVICE);
if (skb->ip_summed == CHECKSUM_PARTIAL &&
ip_hdr(skb)->protocol != IPPROTO_TCP && skb_checksum_help(skb)) {
@@ -875,12 +922,16 @@ static int ibmveth_start_xmit(struct sk_
buf[1] = 0;
}
- if (dma_mapping_error(desc.fields.address)) {
- ibmveth_error_printk("tx: unable to map xmit buffer\n");
+ if (dma_mapping_error(data_dma_addr)) {
+ if (!firmware_has_feature(FW_FEATURE_CMO))
+ ibmveth_error_printk("tx: unable to map xmit buffer\n");
+ skb_copy_from_linear_data(skb, adapter->bounce_buffer,
+ skb->len);
+ desc.fields.address = adapter->bounce_buffer_dma;
tx_map_failed++;
- tx_dropped++;
- goto out;
- }
+ used_bounce = 1;
+ } else
+ desc.fields.address = data_dma_addr;
/* send the frame. Arbitrarily set retrycount to 1024 */
correlator = 0;
@@ -904,8 +955,9 @@ static int ibmveth_start_xmit(struct sk_
netdev->trans_start = jiffies;
}
- dma_unmap_single(&adapter->vdev->dev, desc.fields.address,
- skb->len, DMA_TO_DEVICE);
+ if (!used_bounce)
+ dma_unmap_single(&adapter->vdev->dev, data_dma_addr,
+ skb->len, DMA_TO_DEVICE);
out: spin_lock_irqsave(&adapter->stats_lock, flags);
netdev->stats.tx_dropped += tx_dropped;
@@ -1053,8 +1105,9 @@ static void ibmveth_set_multicast_list(s
static int ibmveth_change_mtu(struct net_device *dev, int new_mtu)
{
struct ibmveth_adapter *adapter = dev->priv;
+ struct vio_dev *viodev = adapter->vdev;
int new_mtu_oh = new_mtu + IBMVETH_BUFF_OH;
- int i, rc;
+ int i;
if (new_mtu < IBMVETH_MAX_MTU)
return -EINVAL;
@@ -1085,10 +1138,15 @@ static int ibmveth_change_mtu(struct net
ibmveth_close(adapter->netdev);
adapter->pool_config = 0;
dev->mtu = new_mtu;
- if ((rc = ibmveth_open(adapter->netdev)))
- return rc;
- } else
- dev->mtu = new_mtu;
+ vio_cmo_set_dev_desired(viodev,
+ ibmveth_get_io_entitlement
+ (viodev));
+ return ibmveth_open(adapter->netdev);
+ }
+ dev->mtu = new_mtu;
+ vio_cmo_set_dev_desired(viodev,
+ ibmveth_get_io_entitlement
+ (viodev));
return 0;
}
}
@@ -1103,6 +1161,46 @@ static void ibmveth_poll_controller(stru
}
#endif
+/**
+ * ibmveth_get_io_entitlement - Calculate IO entitlement needed by the driver
+ *
+ * @vdev: struct vio_dev for the device whose entitlement is to be returned
+ *
+ * Return value:
+ * Number of bytes of IO data the driver will need to perform well.
+ */
+static unsigned long ibmveth_get_io_entitlement(struct vio_dev *vdev)
+{
+ struct net_device *netdev = dev_get_drvdata(&vdev->dev);
+ struct ibmveth_adapter *adapter;
+ unsigned long ret;
+ int i;
+ int rxqentries = 1;
+
+ /* netdev inits at probe time along with the structures we need below*/
+ if (netdev == NULL)
+ return IOMMU_PAGE_ALIGN(IBMVETH_IO_ENTITLEMENT_DEFAULT);
+
+ adapter = netdev_priv(netdev);
+
+ ret = IBMVETH_BUFF_LIST_SIZE + IBMVETH_FILT_LIST_SIZE;
+ ret += IOMMU_PAGE_ALIGN(netdev->mtu);
+
+ for (i = 0; i < IbmVethNumBufferPools; i++) {
+ /* add the size of the active receive buffers */
+ if (adapter->rx_buff_pool[i].active)
+ ret +=
+ adapter->rx_buff_pool[i].size *
+ IOMMU_PAGE_ALIGN(adapter->rx_buff_pool[i].
+ buff_size);
+ rxqentries += adapter->rx_buff_pool[i].size;
+ }
+ /* add the size of the receive queue entries */
+ ret += IOMMU_PAGE_ALIGN(rxqentries * sizeof(struct ibmveth_rx_q_entry));
+
+ return ret;
+}
+
static int __devinit ibmveth_probe(struct vio_dev *dev, const struct vio_device_id *id)
{
int rc, i;
@@ -1247,6 +1345,8 @@ static int __devexit ibmveth_remove(stru
ibmveth_proc_unregister_adapter(adapter);
free_netdev(netdev);
+ dev_set_drvdata(&dev->dev, NULL);
+
return 0;
}
@@ -1491,6 +1591,7 @@ static struct vio_driver ibmveth_driver
.id_table = ibmveth_device_table,
.probe = ibmveth_probe,
.remove = ibmveth_remove,
+ .get_io_entitlement = ibmveth_get_io_entitlement,
.driver = {
.name = ibmveth_driver_name,
.owner = THIS_MODULE,
Index: b/drivers/net/ibmveth.h
===================================================================
--- a/drivers/net/ibmveth.h
+++ b/drivers/net/ibmveth.h
@@ -93,9 +93,12 @@ static inline long h_illan_attributes(un
plpar_hcall_norets(H_CHANGE_LOGICAL_LAN_MAC, ua, mac)
#define IbmVethNumBufferPools 5
+#define IBMVETH_IO_ENTITLEMENT_DEFAULT 4243456 /* MTU of 1500 needs 4.2Mb */
#define IBMVETH_BUFF_OH 22 /* Overhead: 14 ethernet header + 8 opaque handle */
#define IBMVETH_MAX_MTU 68
#define IBMVETH_MAX_POOL_COUNT 4096
+#define IBMVETH_BUFF_LIST_SIZE 4096
+#define IBMVETH_FILT_LIST_SIZE 4096
#define IBMVETH_MAX_BUF_SIZE (1024 * 128)
static int pool_size[] = { 512, 1024 * 2, 1024 * 16, 1024 * 32, 1024 * 64 };
@@ -143,6 +146,8 @@ struct ibmveth_adapter {
struct ibmveth_rx_q rx_queue;
int pool_config;
int rx_csum;
+ void *bounce_buffer;
+ dma_addr_t bounce_buffer_dma;
/* adapter specific stats */
u64 replenish_task_cycles;
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