Re: [PATCH v2 1/5] iommu/amd - Add debugfs support

From: Andy Shevchenko
Date: Tue Mar 13 2018 - 13:16:55 EST


On Fri, Mar 9, 2018 at 2:50 AM, Gary R Hook <gary.hook@xxxxxxx> wrote:

> + default n

Redundant


> +#include <linux/pci.h>
> +#include <linux/iommu.h>
> +#include <linux/debugfs.h>

Keep in order?

> +#include "amd_iommu_proto.h"
> +#include "amd_iommu_types.h"

> +/* DebugFS helpers */
> +#define OBUFP (obuf + oboff)
> +#define OBUFLEN obuflen
> +#define OBUFSPC (OBUFLEN - oboff)
> +#define OSCNPRINTF(fmt, ...) \
> + scnprintf(OBUFP, OBUFSPC, fmt, ## __VA_ARGS__)

I don't see any advantages of this. Other way around, they will simple
makes things hard to read an understand in place.


> + for (i = start ; i <= end ; i++)

Missed {}

> + if ((amd_iommu_dev_table[i].data[0] ^ 0x3)
> + || amd_iommu_dev_table[i].data[1])
> + n++;
> + return n;
> +}

> +
> +static ssize_t amd_iommu_debugfs_dtecount_read(struct file *filp,
> + char __user *ubuf,
> + size_t count, loff_t *offp)
> +{
> + struct amd_iommu *iommu = filp->private_data;

> + unsigned int obuflen = 512;

Sounds like way too much.

> + if (!iommu)
> + return 0;

When this possible?

> + obuf = kmalloc(OBUFLEN, GFP_KERNEL);
> + if (!obuf)
> + return -ENOMEM;
> +
> + n = amd_iommu_count_valid_dtes(0, 0xFFFF);
> + oboff += OSCNPRINTF("%d\n", n);

> + return ret;
> +}


> @@ -89,6 +89,7 @@
> #define ACPI_DEVFLAG_ATSDIS 0x10000000
>
> #define LOOP_TIMEOUT 100000
> +
> /*
> * ACPI table definitions
> *

Doesn't belong to the patch.

> +#endif
> +
> +

Extra unneeded line.

--
With Best Regards,
Andy Shevchenko