The following series creates a debugfs directory for AMD IOMMUs,
constructs a framework for additional entries, an online README,
and a method for dumping device table entries. Data is reported
in a default concise mode, but a verbose mode is enabled via a
filesystem entry.
This is the first of three patch series that will expose a number
of IOMMU registers.
---
Gary R Hook (5):
iommu/amd - Add debugfs support
iommu/amd - Add a 'verbose' switch for IOMMU debugfs
iommu/amd - Add a README variable for the IOMMU debugfs
iommu/amd - Expose the active IOMMU device table entries
iommu/amd - Add a debugfs entry to specify a IOMMU device table entry
drivers/iommu/Kconfig | 9 +
drivers/iommu/Makefile | 2
drivers/iommu/amd_iommu_debugfs.c | 428 +++++++++++++++++++++++++++++++++++++
drivers/iommu/amd_iommu_init.c | 7 -
drivers/iommu/amd_iommu_proto.h | 6 +
drivers/iommu/amd_iommu_types.h | 3
6 files changed, 452 insertions(+), 3 deletions(-)
create mode 100644 drivers/iommu/amd_iommu_debugfs.c
--
Create the basic debugfs functions. Expose a count of IOMMU device
table entries that appear to be in use.
Signed-off-by: Gary R Hook <[email protected]>
---
drivers/iommu/Kconfig | 9 +++
drivers/iommu/Makefile | 2 -
drivers/iommu/amd_iommu_debugfs.c | 112 +++++++++++++++++++++++++++++++++++++
drivers/iommu/amd_iommu_init.c | 7 ++
drivers/iommu/amd_iommu_proto.h | 6 ++
drivers/iommu/amd_iommu_types.h | 3 +
6 files changed, 136 insertions(+), 3 deletions(-)
create mode 100644 drivers/iommu/amd_iommu_debugfs.c
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index f3a21343e636..7753989b6be7 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -135,6 +135,15 @@ config AMD_IOMMU_V2
hardware. Select this option if you want to use devices that support
the PCI PRI and PASID interface.
+config AMD_IOMMU_DEBUG
+ bool "Expose AMD IOMMU internals in DebugFS"
+ depends on AMD_IOMMU && DEBUG_FS
+ default n
+ help
+ With this option you can enable access to AMD IOMMU registers and
+ data structures through debugfs. Select this to see information
+ about the internal state of the device.
+
# Intel IOMMU support
config DMAR_TABLE
bool
diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index 1fb695854809..d9e9ed5f6cfc 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -9,7 +9,7 @@ obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE) += io-pgtable-arm.o
obj-$(CONFIG_IOMMU_IOVA) += iova.o
obj-$(CONFIG_OF_IOMMU) += of_iommu.o
obj-$(CONFIG_MSM_IOMMU) += msm_iommu.o
-obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o
+obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o amd_iommu_debugfs.o
obj-$(CONFIG_AMD_IOMMU_V2) += amd_iommu_v2.o
obj-$(CONFIG_ARM_SMMU) += arm-smmu.o
obj-$(CONFIG_ARM_SMMU_V3) += arm-smmu-v3.o
diff --git a/drivers/iommu/amd_iommu_debugfs.c b/drivers/iommu/amd_iommu_debugfs.c
new file mode 100644
index 000000000000..18f70934961d
--- /dev/null
+++ b/drivers/iommu/amd_iommu_debugfs.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD IOMMU driver
+ *
+ * Copyright (C) 2018 Advanced Micro Devices, Inc.
+ *
+ * Author: Gary R Hook <[email protected]>
+ */
+
+#ifdef CONFIG_DEBUG_FS
+
+#include <linux/pci.h>
+#include <linux/iommu.h>
+#include <linux/debugfs.h>
+#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__)
+
+static struct dentry *iommu_debugfs_dir;
+static DEFINE_RWLOCK(iommu_debugfs_lock);
+
+#define MAX_NAME_LEN 20
+
+static unsigned int amd_iommu_count_valid_dtes(int start, int end)
+{
+ unsigned int n = 0;
+ int i;
+
+ /* Scan the DTE table from entry 'start' through entry 'end' for
+ * active entries
+ */
+ for (i = start ; i <= end ; i++)
+ 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;
+ unsigned int oboff = 0;
+ unsigned int n;
+ ssize_t ret;
+ char *obuf;
+
+ if (!iommu)
+ return 0;
+
+ obuf = kmalloc(OBUFLEN, GFP_KERNEL);
+ if (!obuf)
+ return -ENOMEM;
+
+ n = amd_iommu_count_valid_dtes(0, 0xFFFF);
+ oboff += OSCNPRINTF("%d\n", n);
+
+ ret = simple_read_from_buffer(ubuf, count, offp, obuf, oboff);
+ kfree(obuf);
+
+ return ret;
+}
+
+static const struct file_operations amd_iommu_debugfs_dtecount_ops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = amd_iommu_debugfs_dtecount_read,
+ .write = NULL,
+};
+
+void amd_iommu_debugfs_setup(struct amd_iommu *iommu)
+{
+ char name[MAX_NAME_LEN + 1];
+ struct dentry *d_dte;
+ unsigned long flags;
+
+ if (!debugfs_initialized())
+ return;
+
+ write_lock_irqsave(&iommu_debugfs_lock, flags);
+ if (!iommu_debugfs_dir)
+ iommu_debugfs_dir = debugfs_create_dir("amd-iommu", NULL);
+ write_unlock_irqrestore(&iommu_debugfs_lock, flags);
+ if (!iommu_debugfs_dir)
+ goto err;
+
+ snprintf(name, MAX_NAME_LEN, "iommu%02d", iommu->index);
+ iommu->debugfs_instance = debugfs_create_dir(name, iommu_debugfs_dir);
+ if (!iommu->debugfs_instance)
+ goto err;
+
+ d_dte = debugfs_create_file("count", 0400,
+ iommu->debugfs_instance, iommu,
+ &amd_iommu_debugfs_dtecount_ops);
+ if (!d_dte)
+ goto err;
+
+ return;
+
+err:
+ debugfs_remove_recursive(iommu->debugfs_instance);
+}
+
+#endif
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 6fe2d0346073..43856c7f4ea1 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -89,6 +89,7 @@
#define ACPI_DEVFLAG_ATSDIS 0x10000000
#define LOOP_TIMEOUT 100000
+
/*
* ACPI table definitions
*
@@ -2720,6 +2721,7 @@ int __init amd_iommu_enable_faulting(void)
*/
static int __init amd_iommu_init(void)
{
+ struct amd_iommu *iommu;
int ret;
ret = iommu_go_to_state(IOMMU_INITIALIZED);
@@ -2729,14 +2731,15 @@ static int __init amd_iommu_init(void)
disable_iommus();
free_iommu_resources();
} else {
- struct amd_iommu *iommu;
-
uninit_device_table_dma();
for_each_iommu(iommu)
iommu_flush_all_caches(iommu);
}
}
+ for_each_iommu(iommu)
+ amd_iommu_debugfs_setup(iommu);
+
return ret;
}
diff --git a/drivers/iommu/amd_iommu_proto.h b/drivers/iommu/amd_iommu_proto.h
index 640c286a0ab9..f2a978dbcff7 100644
--- a/drivers/iommu/amd_iommu_proto.h
+++ b/drivers/iommu/amd_iommu_proto.h
@@ -33,6 +33,12 @@ extern void amd_iommu_uninit_devices(void);
extern void amd_iommu_init_notifier(void);
extern int amd_iommu_init_api(void);
+#ifdef CONFIG_DEBUG_FS
+extern void amd_iommu_debugfs_setup(struct amd_iommu *iommu);
+#else
+static inline void amd_iommu_debugfs_setup(struct amd_iommu *iommu) {}
+#endif
+
/* Needed for interrupt remapping */
extern int amd_iommu_prepare(void);
extern int amd_iommu_enable(void);
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index 6a877ebd058b..43c008dc7ade 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -593,6 +593,9 @@ struct amd_iommu {
u32 flags;
volatile u64 __aligned(8) cmd_sem;
+
+ /* DebugFS Info */
+ struct dentry *debugfs_instance;
};
static inline struct amd_iommu *dev_to_amd_iommu(struct device *dev)
Enable more descriptive debugfs output via a 'verbose' variable.
Signed-off-by: Gary R Hook <[email protected]>
---
drivers/iommu/amd_iommu_debugfs.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/amd_iommu_debugfs.c b/drivers/iommu/amd_iommu_debugfs.c
index 18f70934961d..c449f3a7452c 100644
--- a/drivers/iommu/amd_iommu_debugfs.c
+++ b/drivers/iommu/amd_iommu_debugfs.c
@@ -27,6 +27,8 @@ static DEFINE_RWLOCK(iommu_debugfs_lock);
#define MAX_NAME_LEN 20
+static unsigned int amd_iommu_verbose;
+
static unsigned int amd_iommu_count_valid_dtes(int start, int end)
{
unsigned int n = 0;
@@ -61,7 +63,10 @@ static ssize_t amd_iommu_debugfs_dtecount_read(struct file *filp,
return -ENOMEM;
n = amd_iommu_count_valid_dtes(0, 0xFFFF);
- oboff += OSCNPRINTF("%d\n", n);
+ if (amd_iommu_verbose)
+ oboff += OSCNPRINTF("# DTEs: %d\n", n);
+ else
+ oboff += OSCNPRINTF("%d\n", n);
ret = simple_read_from_buffer(ubuf, count, offp, obuf, oboff);
kfree(obuf);
@@ -79,6 +84,7 @@ static const struct file_operations amd_iommu_debugfs_dtecount_ops = {
void amd_iommu_debugfs_setup(struct amd_iommu *iommu)
{
char name[MAX_NAME_LEN + 1];
+ struct dentry *d_verbose;
struct dentry *d_dte;
unsigned long flags;
@@ -97,6 +103,12 @@ void amd_iommu_debugfs_setup(struct amd_iommu *iommu)
if (!iommu->debugfs_instance)
goto err;
+ d_verbose = debugfs_create_u32("verbose", 0600,
+ iommu->debugfs_instance,
+ &amd_iommu_verbose);
+ if (!d_verbose)
+ goto err;
+
d_dte = debugfs_create_file("count", 0400,
iommu->debugfs_instance, iommu,
&amd_iommu_debugfs_dtecount_ops);
Provide help text via a filesystem entry
Signed-off-by: Gary R Hook <[email protected]>
---
drivers/iommu/amd_iommu_debugfs.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)
diff --git a/drivers/iommu/amd_iommu_debugfs.c b/drivers/iommu/amd_iommu_debugfs.c
index c449f3a7452c..5066d3976912 100644
--- a/drivers/iommu/amd_iommu_debugfs.c
+++ b/drivers/iommu/amd_iommu_debugfs.c
@@ -81,6 +81,31 @@ static const struct file_operations amd_iommu_debugfs_dtecount_ops = {
.write = NULL,
};
+static char readmetext[] =
+"count Count of active devices\n"
+"verbose Provide additional descriptive text\n"
+"\n";
+
+static ssize_t amd_iommu_debugfs_readme_read(struct file *filp,
+ char __user *ubuf,
+ size_t count, loff_t *offp)
+{
+ ssize_t ret;
+
+ ret = simple_read_from_buffer(ubuf, count, offp,
+ readmetext, strlen(readmetext));
+
+ return ret;
+}
+
+
+static const struct file_operations amd_iommu_debugfs_readme_ops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = amd_iommu_debugfs_readme_read,
+ .write = NULL,
+};
+
void amd_iommu_debugfs_setup(struct amd_iommu *iommu)
{
char name[MAX_NAME_LEN + 1];
@@ -115,6 +140,12 @@ void amd_iommu_debugfs_setup(struct amd_iommu *iommu)
if (!d_dte)
goto err;
+ d_dte = debugfs_create_file("README", 0400,
+ iommu->debugfs_instance, iommu,
+ &amd_iommu_debugfs_readme_ops);
+ if (!d_dte)
+ goto err;
+
return;
err:
Add a debugfs entry to dump the active device table entries from
the IOMMU's table. 'Active' is determined by non-default values
in the first and second long words of the DTE. Aside from IOMMU
devices, this output should list every device reported by lspci.
Use arrays to store DTE bit field definitions for debugfs printing
in verbose mode
Signed-off-by: Gary R Hook <[email protected]>
---
drivers/iommu/amd_iommu_debugfs.c | 182 +++++++++++++++++++++++++++++++++++++
1 file changed, 182 insertions(+)
diff --git a/drivers/iommu/amd_iommu_debugfs.c b/drivers/iommu/amd_iommu_debugfs.c
index 5066d3976912..87840ae9889d 100644
--- a/drivers/iommu/amd_iommu_debugfs.c
+++ b/drivers/iommu/amd_iommu_debugfs.c
@@ -22,6 +22,16 @@
#define OSCNPRINTF(fmt, ...) \
scnprintf(OBUFP, OBUFSPC, fmt, ## __VA_ARGS__)
+#define MAX_PCI_ID 0xFFFF
+
+#define PRINTDTE(i) OSCNPRINTF("%02x:%02x:%x - " \
+ "%016llx %016llx %016llx %016llx\n", \
+ PCI_BUS_NUM(i), PCI_SLOT(i), PCI_FUNC(i), \
+ amd_iommu_dev_table[i].data[0], \
+ amd_iommu_dev_table[i].data[1], \
+ amd_iommu_dev_table[i].data[2], \
+ amd_iommu_dev_table[i].data[3])
+
static struct dentry *iommu_debugfs_dir;
static DEFINE_RWLOCK(iommu_debugfs_lock);
@@ -81,9 +91,174 @@ static const struct file_operations amd_iommu_debugfs_dtecount_ops = {
.write = NULL,
};
+struct bits {
+ uint bit;
+ uint len;
+ char *lbl;
+ char *note;
+};
+
+static struct bits dte_lft[] = {
+ { 0, 1, "V:", "[0]" },
+ { 1, 1, "TV:", "[1]" },
+ { 7, 2, "Host Access Dirty:", "[8:7]" },
+ { 9, 3, "Paging Mode:", "[11:9]" },
+ { 52, 1, "PPR:", "[52]" },
+ { 53, 1, "GPRP:", "[53]" },
+ { 54, 1, "GIoV:", "[54]" },
+ { 55, 1, "GV:", "[55]" },
+ { 56, 2, "GLX:", "[57:56]" },
+ { 61, 1, "IR:", "[61]" },
+ { 62, 1, "IW:", "[62]" },
+ { 96, 1, "I:", "[96]" },
+ { 97, 1, "SE:", "[97]" },
+ { 98, 1, "SA:", "[98]" },
+ { 99, 2, "IOCtl:", "[100:99]" },
+};
+static uint lftlen = sizeof(dte_lft) / sizeof(struct bits);
+
+static struct bits dte_rght[] = {
+ { 101, 1, "Cache:", "[101]" },
+ { 102, 1, "SD:", "[102]" },
+ { 103, 1, "EX :", "[103]" },
+ { 104, 2, "SysMgt:", "[105:104]" },
+ { 128, 1, "IV:", "[128]" },
+ { 129, 4, "IntTabLen:", "[132:129]" },
+ { 133, 1, "IG:", "[133]" },
+ { 184, 1, "InitPass:", "[184]" },
+ { 185, 1, "EIntPass:", "[185]" },
+ { 186, 1, "NMIPass:", "[186]" },
+ { 188, 2, "IntClt:", "[189:188]" },
+ { 190, 1, "Lint0Pass:", "[190]" },
+ { 191, 1, "Lint1Pass:", "[191]" },
+ { 246, 1, "AttrV:", "[246]" },
+ { 247, 1, "Mode0FC:", "[247]" },
+};
+static uint rghtlen = sizeof(dte_rght) / sizeof(struct bits);
+
+#define DTE_BIT(ds, p, n) ((ds[p/64] >> (p%64)) & ((1ULL<<n) - 1))
+
+static void amd_iommu_print_dte_verbose(int devidx, char **buf,
+ unsigned int *buflen,
+ unsigned int *offset)
+{
+ u64 *dte = amd_iommu_dev_table[devidx].data;
+ u64 part1, part2, part3;
+ unsigned int obuflen = *buflen;
+ unsigned int oboff = *offset;
+ struct bits *lft, *rght;
+ char *obuf = *buf;
+ uint max;
+ int j;
+
+ max = lftlen > rghtlen ? lftlen : rghtlen;
+
+ for (j = 0; j < max ; j++) {
+ lft = &dte_lft[j];
+ if (j < lftlen)
+ oboff += OSCNPRINTF("%-19s%3llx %*s", lft->lbl,
+ DTE_BIT(dte, lft->bit, lft->len),
+ (j < rghtlen) ? -16 : 1,
+ lft->note);
+ else
+ oboff += OSCNPRINTF("%38s", "");
+
+ rght = &dte_rght[j];
+ if (j < rghtlen)
+ oboff += OSCNPRINTF(" %-19s%3llx %s\n", rght->lbl,
+ DTE_BIT(dte, rght->bit, rght->len),
+ rght->note);
+ else
+ oboff += OSCNPRINTF("\n");
+ }
+
+ oboff += OSCNPRINTF("%-28s: %4llx %s\n", "Domain ID",
+ DTE_BIT(dte, 64, 16), "[79:64]");
+ oboff += OSCNPRINTF("%-28s: %4llx %s\n", "Snoop Attribute",
+ DTE_BIT(dte, 248, 8), "[255:248]");
+ oboff += OSCNPRINTF("%-28s: %12llx %s\n", "Page Table Root Pointer",
+ DTE_BIT(dte, 12, 40) << 12, "[51:12]");
+ oboff += OSCNPRINTF("%-28s: %12llx %s\n",
+ "Interrupt Table Root Pointer",
+ DTE_BIT(dte, 134, 46) << 6, "[179:134]");
+
+ part1 = DTE_BIT(dte, 107, 21) << 19;
+ part2 = DTE_BIT(dte, 80, 16) << 3;
+ part3 = DTE_BIT(dte, 58, 3);
+ oboff += OSCNPRINTF("%-28s: %12llx %s\n\n",
+ "Guest CR3 Table Root Pointer",
+ (part1 | part2 | part3) << 12,
+ "[127:107][95:80][60:58]");
+
+ *buflen = obuflen;
+ *offset = oboff;
+ *buf = obuf;
+}
+
+static ssize_t amd_iommu_debugfs_dte_read(struct file *filp,
+ char __user *ubuf,
+ size_t count, loff_t *offp)
+{
+ struct amd_iommu *iommu = filp->private_data;
+ unsigned int obuflen;
+ unsigned int oboff = 0;
+ unsigned int istart, iend;
+ ssize_t ret;
+ u32 i, n;
+ char *obuf;
+
+ if (!iommu)
+ return 0;
+
+ /* Count the number of valid entries in the device table */
+ istart = 0;
+ iend = MAX_PCI_ID;
+ n = amd_iommu_count_valid_dtes(istart, iend);
+ if (amd_iommu_verbose)
+ obuflen = n * 2048;
+ else
+ obuflen = n * 80;
+
+ obuf = kmalloc(OBUFLEN, GFP_KERNEL);
+ if (!obuf)
+ return -ENOMEM;
+
+ for (i = istart ; i <= iend ; i++)
+ if ((amd_iommu_dev_table[i].data[0] ^ 0x3)
+ || amd_iommu_dev_table[i].data[1]) {
+ if (amd_iommu_verbose) {
+ oboff += OSCNPRINTF("Device %02x:%02x.%x\n",
+ PCI_BUS_NUM(i),
+ PCI_SLOT(i),
+ PCI_FUNC(i));
+ amd_iommu_print_dte_verbose(i, &obuf,
+ &obuflen, &oboff);
+ } else {
+ oboff += PRINTDTE(i);
+ }
+ }
+
+ ret = simple_read_from_buffer(ubuf, count, offp, obuf, oboff);
+ kfree(obuf);
+
+ return ret;
+}
+
+static const struct file_operations amd_iommu_debugfs_dte_ops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = amd_iommu_debugfs_dte_read,
+ .write = NULL,
+};
+
static char readmetext[] =
+"devicetable Print active entries in the device table\n"
"count Count of active devices\n"
"verbose Provide additional descriptive text\n"
+"\n"
+" Dumping the Device Table\n"
+"The device table is scanned for entries that appear to be active. The\n"
+"default range is from 0 to 0xFFFF, and only active entries will be reported\n"
"\n";
static ssize_t amd_iommu_debugfs_readme_read(struct file *filp,
@@ -134,6 +309,13 @@ void amd_iommu_debugfs_setup(struct amd_iommu *iommu)
if (!d_verbose)
goto err;
+ /* Device Table Entries */
+ d_dte = debugfs_create_file("devicetable", 0400,
+ iommu->debugfs_instance, iommu,
+ &amd_iommu_debugfs_dte_ops);
+ if (!d_dte)
+ goto err;
+
d_dte = debugfs_create_file("count", 0400,
iommu->debugfs_instance, iommu,
&amd_iommu_debugfs_dtecount_ops);
Initially (at boot) the device table values dumped are all of the
active devices. Add a devid debugfs file to allow the user to select a
single device table entry to dump (active or not). Let any devid value
greater than the maximum allowable PCI ID (0xFFFF) restore the
behavior to that effective at boot.
Signed-off-by: Gary R Hook <[email protected]>
---
drivers/iommu/amd_iommu_debugfs.c | 127 ++++++++++++++++++++++++++++++++-----
1 file changed, 109 insertions(+), 18 deletions(-)
diff --git a/drivers/iommu/amd_iommu_debugfs.c b/drivers/iommu/amd_iommu_debugfs.c
index 87840ae9889d..efb666873daa 100644
--- a/drivers/iommu/amd_iommu_debugfs.c
+++ b/drivers/iommu/amd_iommu_debugfs.c
@@ -38,6 +38,7 @@ static DEFINE_RWLOCK(iommu_debugfs_lock);
#define MAX_NAME_LEN 20
static unsigned int amd_iommu_verbose;
+static unsigned int amd_iommu_devid = ~0;
static unsigned int amd_iommu_count_valid_dtes(int start, int end)
{
@@ -91,6 +92,72 @@ static const struct file_operations amd_iommu_debugfs_dtecount_ops = {
.write = NULL,
};
+static ssize_t amd_iommu_debugfs_devid_read(struct file *filp,
+ char __user *ubuf,
+ size_t count, loff_t *offp)
+{
+ struct amd_iommu *iommu = filp->private_data;
+ unsigned int obuflen = 512;
+ unsigned int oboff = 0;
+ ssize_t ret;
+ char *obuf;
+
+ if (!iommu)
+ return 0;
+
+ obuf = kmalloc(OBUFLEN, GFP_KERNEL);
+ if (!obuf)
+ return -ENOMEM;
+
+ if (amd_iommu_verbose)
+ oboff += OSCNPRINTF("%02x:%02x.%x 0x%04x %u\n",
+ PCI_BUS_NUM(amd_iommu_devid),
+ PCI_SLOT(amd_iommu_devid),
+ PCI_FUNC(amd_iommu_devid),
+ amd_iommu_devid, amd_iommu_devid);
+ else
+ oboff += OSCNPRINTF("%u\n", amd_iommu_devid);
+
+ ret = simple_read_from_buffer(ubuf, count, offp, obuf, oboff);
+ kfree(obuf);
+
+ return ret;
+}
+
+static ssize_t amd_iommu_debugfs_devid_write(struct file *filp,
+ const char __user *ubuf,
+ size_t count, loff_t *offp)
+{
+ unsigned int pci_id, pci_slot, pci_func;
+ unsigned int obuflen = 80;
+ ssize_t ret;
+ char *obuf;
+ int n;
+
+ obuf = kmalloc(OBUFLEN, GFP_KERNEL);
+ if (!obuf)
+ return -ENOMEM;
+
+ ret = simple_write_to_buffer(obuf, OBUFLEN, offp, ubuf, count);
+
+ if (strnchr(obuf, OBUFLEN, ':')) {
+ n = sscanf(obuf, "%x:%x.%x", &pci_id, &pci_slot, &pci_func);
+ if (n == 3)
+ amd_iommu_devid = PCI_DEVID(pci_id, PCI_DEVFN(pci_slot, pci_func));
+ } else
+ n = kstrtouint(obuf, 0, &amd_iommu_devid);
+ kfree(obuf);
+
+ return ret;
+}
+
+static const struct file_operations amd_iommu_debugfs_devid_ops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = amd_iommu_debugfs_devid_read,
+ .write = amd_iommu_debugfs_devid_write,
+};
+
struct bits {
uint bit;
uint len;
@@ -211,9 +278,13 @@ static ssize_t amd_iommu_debugfs_dte_read(struct file *filp,
return 0;
/* Count the number of valid entries in the device table */
- istart = 0;
- iend = MAX_PCI_ID;
- n = amd_iommu_count_valid_dtes(istart, iend);
+ if (amd_iommu_devid > MAX_PCI_ID) {
+ istart = 0;
+ iend = MAX_PCI_ID;
+ n = amd_iommu_count_valid_dtes(istart, iend);
+ } else {
+ n = 1;
+ }
if (amd_iommu_verbose)
obuflen = n * 2048;
else
@@ -223,20 +294,29 @@ static ssize_t amd_iommu_debugfs_dte_read(struct file *filp,
if (!obuf)
return -ENOMEM;
- for (i = istart ; i <= iend ; i++)
- if ((amd_iommu_dev_table[i].data[0] ^ 0x3)
- || amd_iommu_dev_table[i].data[1]) {
- if (amd_iommu_verbose) {
- oboff += OSCNPRINTF("Device %02x:%02x.%x\n",
- PCI_BUS_NUM(i),
- PCI_SLOT(i),
- PCI_FUNC(i));
- amd_iommu_print_dte_verbose(i, &obuf,
- &obuflen, &oboff);
- } else {
- oboff += PRINTDTE(i);
+ if (amd_iommu_devid > MAX_PCI_ID) {
+ for (i = istart ; i <= iend ; i++)
+ if ((amd_iommu_dev_table[i].data[0] ^ 0x3)
+ || amd_iommu_dev_table[i].data[1]) {
+ if (amd_iommu_verbose) {
+ oboff += OSCNPRINTF("Device %02x:%02x.%x\n",
+ PCI_BUS_NUM(i),
+ PCI_SLOT(i),
+ PCI_FUNC(i));
+ amd_iommu_print_dte_verbose(i, &obuf,
+ &obuflen,
+ &oboff);
+ } else {
+ oboff += PRINTDTE(i);
+ }
}
- }
+ } else {
+ i = amd_iommu_devid;
+ if (amd_iommu_verbose)
+ amd_iommu_print_dte_verbose(i, &obuf, &obuflen, &oboff);
+ else
+ oboff += PRINTDTE(i);
+ }
ret = simple_read_from_buffer(ubuf, count, offp, obuf, oboff);
kfree(obuf);
@@ -253,12 +333,17 @@ static const struct file_operations amd_iommu_debugfs_dte_ops = {
static char readmetext[] =
"devicetable Print active entries in the device table\n"
+"devid Controls which device IDs are printed\n"
"count Count of active devices\n"
"verbose Provide additional descriptive text\n"
"\n"
" Dumping the Device Table\n"
-"The device table is scanned for entries that appear to be active. The\n"
-"default range is from 0 to 0xFFFF, and only active entries will be reported\n"
+"The device table is scanned for entries that appear to be active.\n"
+"The default (initial) range is from 0 to 0xFFFF, represented by a devid\n"
+"value greater than 0xFFFF, and only active entries will be reported.\n"
+"If devid is set to a specific value, only that device entry will be\n"
+"displayed (active or not). devid may be specified as ##:##:#, a decimal\n"
+"value, or a hex value.\n"
"\n";
static ssize_t amd_iommu_debugfs_readme_read(struct file *filp,
@@ -322,6 +407,12 @@ void amd_iommu_debugfs_setup(struct amd_iommu *iommu)
if (!d_dte)
goto err;
+ d_dte = debugfs_create_file("devid", 0400,
+ iommu->debugfs_instance, iommu,
+ &amd_iommu_debugfs_devid_ops);
+ if (!d_dte)
+ goto err;
+
d_dte = debugfs_create_file("README", 0400,
iommu->debugfs_instance, iommu,
&amd_iommu_debugfs_readme_ops);
On Fri, Jan 26, 2018 at 05:52:15PM -0600, Gary R Hook wrote:
> Create the basic debugfs functions. Expose a count of IOMMU device
> table entries that appear to be in use.
>
> Signed-off-by: Gary R Hook <[email protected]>
> ---
> drivers/iommu/Kconfig | 9 +++
> drivers/iommu/Makefile | 2 -
> drivers/iommu/amd_iommu_debugfs.c | 112 +++++++++++++++++++++++++++++++++++++
> drivers/iommu/amd_iommu_init.c | 7 ++
> drivers/iommu/amd_iommu_proto.h | 6 ++
> drivers/iommu/amd_iommu_types.h | 3 +
> 6 files changed, 136 insertions(+), 3 deletions(-)
> create mode 100644 drivers/iommu/amd_iommu_debugfs.c
>
> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> index f3a21343e636..7753989b6be7 100644
> --- a/drivers/iommu/Kconfig
> +++ b/drivers/iommu/Kconfig
> @@ -135,6 +135,15 @@ config AMD_IOMMU_V2
> hardware. Select this option if you want to use devices that support
> the PCI PRI and PASID interface.
>
> +config AMD_IOMMU_DEBUG
> + bool "Expose AMD IOMMU internals in DebugFS"
> + depends on AMD_IOMMU && DEBUG_FS
> + default n
> + help
> + With this option you can enable access to AMD IOMMU registers and
> + data structures through debugfs. Select this to see information
> + about the internal state of the device.
> +
> # Intel IOMMU support
> config DMAR_TABLE
> bool
> diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
> index 1fb695854809..d9e9ed5f6cfc 100644
> --- a/drivers/iommu/Makefile
> +++ b/drivers/iommu/Makefile
> @@ -9,7 +9,7 @@ obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE) += io-pgtable-arm.o
> obj-$(CONFIG_IOMMU_IOVA) += iova.o
> obj-$(CONFIG_OF_IOMMU) += of_iommu.o
> obj-$(CONFIG_MSM_IOMMU) += msm_iommu.o
> -obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o
> +obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o amd_iommu_debugfs.o
That looks like it needs to be:
obj-$(CONFIG_AMD_IOMMU_DEBUG) += amd_iommu_debugfs.o
--
Regards/Gruss,
Boris.
Good mailing practices for 400: avoid top-posting and trim the reply.
On 01/26/2018 06:00 PM, Borislav Petkov wrote:
> On Fri, Jan 26, 2018 at 05:52:15PM -0600, Gary R Hook wrote:
>> --- a/drivers/iommu/Kconfig
>> +++ b/drivers/iommu/Kconfig
>> @@ -135,6 +135,15 @@ config AMD_IOMMU_V2
>> hardware. Select this option if you want to use devices that support
>> the PCI PRI and PASID interface.
>>
>> +config AMD_IOMMU_DEBUG
>> + bool "Expose AMD IOMMU internals in DebugFS"
>> + depends on AMD_IOMMU && DEBUG_FS
>> + default n
>> + help
>> + With this option you can enable access to AMD IOMMU registers and
>> + data structures through debugfs. Select this to see information
>> + about the internal state of the device.
>> +
>> # Intel IOMMU support
>> config DMAR_TABLE
>> bool
>> diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
>> index 1fb695854809..d9e9ed5f6cfc 100644
>> --- a/drivers/iommu/Makefile
>> +++ b/drivers/iommu/Makefile
>> @@ -9,7 +9,7 @@ obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE) += io-pgtable-arm.o
>> obj-$(CONFIG_IOMMU_IOVA) += iova.o
>> obj-$(CONFIG_OF_IOMMU) += of_iommu.o
>> obj-$(CONFIG_MSM_IOMMU) += msm_iommu.o
>> -obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o
>> +obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o amd_iommu_debugfs.o
>
> That looks like it needs to be:
>
> obj-$(CONFIG_AMD_IOMMU_DEBUG) += amd_iommu_debugfs.o
Of course. Thanks, Boris. I'll get that in v2.