ntb_tool: Add memory window debug support

We allocate some memory window buffers when the link comes up, then we
provide debugfs files to read/write each side of the link.

This is useful for debugging the mapping when writing new drivers.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Allen Hubbe <Allen.Hubbe@emc.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
This commit is contained in:
Logan Gunthorpe 2016-06-03 14:50:33 -06:00 committed by Jon Mason
parent 4aae977721
commit 8b71d28506
1 changed files with 257 additions and 1 deletions

View File

@ -89,6 +89,7 @@
#include <linux/dma-mapping.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/ntb.h>
@ -105,11 +106,29 @@ MODULE_VERSION(DRIVER_VERSION);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
#define MAX_MWS 16
static unsigned long mw_size = 16;
module_param(mw_size, ulong, 0644);
MODULE_PARM_DESC(mw_size, "size order [n^2] of the memory window for testing");
static struct dentry *tool_dbgfs;
struct tool_mw {
resource_size_t size;
u8 __iomem *local;
u8 *peer;
dma_addr_t peer_dma;
};
struct tool_ctx {
struct ntb_dev *ntb;
struct dentry *dbgfs;
struct work_struct link_cleanup;
bool link_is_up;
struct delayed_work link_work;
int mw_count;
struct tool_mw mws[MAX_MWS];
};
#define SPAD_FNAME_SIZE 0x10
@ -124,6 +143,111 @@ struct tool_ctx {
.write = __write, \
}
static int tool_setup_mw(struct tool_ctx *tc, int idx)
{
int rc;
struct tool_mw *mw = &tc->mws[idx];
phys_addr_t base;
resource_size_t size, align, align_size;
if (mw->local)
return 0;
rc = ntb_mw_get_range(tc->ntb, idx, &base, &size, &align,
&align_size);
if (rc)
return rc;
mw->size = min_t(resource_size_t, 1 << mw_size, size);
mw->size = round_up(mw->size, align);
mw->size = round_up(mw->size, align_size);
mw->local = ioremap_wc(base, size);
if (mw->local == NULL)
return -EFAULT;
mw->peer = dma_alloc_coherent(&tc->ntb->pdev->dev, mw->size,
&mw->peer_dma, GFP_KERNEL);
if (mw->peer == NULL)
return -ENOMEM;
rc = ntb_mw_set_trans(tc->ntb, idx, mw->peer_dma, mw->size);
if (rc)
return rc;
return 0;
}
static void tool_free_mws(struct tool_ctx *tc)
{
int i;
for (i = 0; i < tc->mw_count; i++) {
if (tc->mws[i].peer) {
ntb_mw_clear_trans(tc->ntb, i);
dma_free_coherent(&tc->ntb->pdev->dev, tc->mws[i].size,
tc->mws[i].peer,
tc->mws[i].peer_dma);
}
tc->mws[i].peer = NULL;
tc->mws[i].peer_dma = 0;
if (tc->mws[i].local)
iounmap(tc->mws[i].local);
tc->mws[i].local = NULL;
}
tc->mw_count = 0;
}
static int tool_setup_mws(struct tool_ctx *tc)
{
int i;
int rc;
tc->mw_count = min(ntb_mw_count(tc->ntb), MAX_MWS);
for (i = 0; i < tc->mw_count; i++) {
rc = tool_setup_mw(tc, i);
if (rc)
goto err_out;
}
return 0;
err_out:
tool_free_mws(tc);
return rc;
}
static void tool_link_work(struct work_struct *work)
{
int rc;
struct tool_ctx *tc = container_of(work, struct tool_ctx,
link_work.work);
tool_free_mws(tc);
rc = tool_setup_mws(tc);
if (rc)
dev_err(&tc->ntb->dev,
"Error setting up memory windows: %d\n", rc);
tc->link_is_up = true;
}
static void tool_link_cleanup(struct work_struct *work)
{
struct tool_ctx *tc = container_of(work, struct tool_ctx,
link_cleanup);
if (!tc->link_is_up)
cancel_delayed_work_sync(&tc->link_work);
}
static void tool_link_event(void *ctx)
{
struct tool_ctx *tc = ctx;
@ -135,6 +259,11 @@ static void tool_link_event(void *ctx)
dev_dbg(&tc->ntb->dev, "link is %s speed %d width %d\n",
up ? "up" : "down", speed, width);
if (up)
schedule_delayed_work(&tc->link_work, 2*HZ);
else
schedule_work(&tc->link_cleanup);
}
static void tool_db_event(void *ctx, int vec)
@ -449,8 +578,112 @@ static TOOL_FOPS_RDWR(tool_peer_spad_fops,
tool_peer_spad_read,
tool_peer_spad_write);
static ssize_t tool_mw_read(struct file *filep, char __user *ubuf,
size_t size, loff_t *offp)
{
struct tool_mw *mw = filep->private_data;
ssize_t rc;
loff_t pos = *offp;
void *buf;
if (mw->local == NULL)
return -EIO;
if (pos < 0)
return -EINVAL;
if (pos >= mw->size || !size)
return 0;
if (size > mw->size - pos)
size = mw->size - pos;
buf = kmalloc(size, GFP_KERNEL);
if (!buf)
return -ENOMEM;
memcpy_fromio(buf, mw->local + pos, size);
rc = copy_to_user(ubuf, buf, size);
if (rc == size) {
rc = -EFAULT;
goto err_free;
}
size -= rc;
*offp = pos + size;
rc = size;
err_free:
kfree(buf);
return rc;
}
static ssize_t tool_mw_write(struct file *filep, const char __user *ubuf,
size_t size, loff_t *offp)
{
struct tool_mw *mw = filep->private_data;
ssize_t rc;
loff_t pos = *offp;
void *buf;
if (pos < 0)
return -EINVAL;
if (pos >= mw->size || !size)
return 0;
if (size > mw->size - pos)
size = mw->size - pos;
buf = kmalloc(size, GFP_KERNEL);
if (!buf)
return -ENOMEM;
rc = copy_from_user(buf, ubuf, size);
if (rc == size) {
rc = -EFAULT;
goto err_free;
}
size -= rc;
*offp = pos + size;
rc = size;
memcpy_toio(mw->local + pos, buf, size);
err_free:
kfree(buf);
return rc;
}
static TOOL_FOPS_RDWR(tool_mw_fops,
tool_mw_read,
tool_mw_write);
static ssize_t tool_peer_mw_read(struct file *filep, char __user *ubuf,
size_t size, loff_t *offp)
{
struct tool_mw *mw = filep->private_data;
return simple_read_from_buffer(ubuf, size, offp, mw->peer, mw->size);
}
static ssize_t tool_peer_mw_write(struct file *filep, const char __user *ubuf,
size_t size, loff_t *offp)
{
struct tool_mw *mw = filep->private_data;
return simple_write_to_buffer(mw->peer, mw->size, offp, ubuf, size);
}
static TOOL_FOPS_RDWR(tool_peer_mw_fops,
tool_peer_mw_read,
tool_peer_mw_write);
static void tool_setup_dbgfs(struct tool_ctx *tc)
{
int mw_count;
int i;
/* This modules is useless without dbgfs... */
if (!tool_dbgfs) {
tc->dbgfs = NULL;
@ -479,6 +712,20 @@ static void tool_setup_dbgfs(struct tool_ctx *tc)
debugfs_create_file("peer_spad", S_IRUSR | S_IWUSR, tc->dbgfs,
tc, &tool_peer_spad_fops);
mw_count = min(ntb_mw_count(tc->ntb), MAX_MWS);
for (i = 0; i < mw_count; i++) {
char buf[30];
snprintf(buf, sizeof(buf), "mw%d", i);
debugfs_create_file(buf, S_IRUSR | S_IWUSR, tc->dbgfs,
&tc->mws[i], &tool_mw_fops);
snprintf(buf, sizeof(buf), "peer_mw%d", i);
debugfs_create_file(buf, S_IRUSR | S_IWUSR, tc->dbgfs,
&tc->mws[i], &tool_peer_mw_fops);
}
}
static int tool_probe(struct ntb_client *self, struct ntb_dev *ntb)
@ -492,13 +739,15 @@ static int tool_probe(struct ntb_client *self, struct ntb_dev *ntb)
if (ntb_spad_is_unsafe(ntb))
dev_dbg(&ntb->dev, "scratchpad is unsafe\n");
tc = kmalloc(sizeof(*tc), GFP_KERNEL);
tc = kzalloc(sizeof(*tc), GFP_KERNEL);
if (!tc) {
rc = -ENOMEM;
goto err_tc;
}
tc->ntb = ntb;
INIT_DELAYED_WORK(&tc->link_work, tool_link_work);
INIT_WORK(&tc->link_cleanup, tool_link_cleanup);
tool_setup_dbgfs(tc);
@ -513,6 +762,8 @@ static int tool_probe(struct ntb_client *self, struct ntb_dev *ntb)
err_ctx:
debugfs_remove_recursive(tc->dbgfs);
cancel_delayed_work_sync(&tc->link_work);
cancel_work_sync(&tc->link_cleanup);
kfree(tc);
err_tc:
return rc;
@ -522,6 +773,11 @@ static void tool_remove(struct ntb_client *self, struct ntb_dev *ntb)
{
struct tool_ctx *tc = ntb->ctx;
cancel_delayed_work_sync(&tc->link_work);
cancel_work_sync(&tc->link_cleanup);
tool_free_mws(tc);
ntb_clear_ctx(ntb);
ntb_link_disable(ntb);