mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-06 10:57:46 +00:00
iommu: Enable debugfs exposure of IOMMU driver internals
Provide base enablement for using debugfs to expose internal data of an IOMMU driver. When called, create the /sys/kernel/debug/iommu directory. Emit a strong warning at boot time to indicate that this feature is enabled. This function is called from iommu_init, and creates the initial DebugFS directory. Drivers may then call iommu_debugfs_new_driver_dir() to instantiate a device-specific directory to expose internal data. It will return a pointer to the new dentry structure created in /sys/kernel/debug/iommu, or NULL in the event of a failure. Since the IOMMU driver can not be removed from the running system, there is no need for an "off" function. Signed-off-by: Gary R Hook <gary.hook@amd.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
parent
021c91791a
commit
bad614b242
5 changed files with 86 additions and 0 deletions
|
@ -60,6 +60,16 @@ config IOMMU_IO_PGTABLE_ARMV7S_SELFTEST
|
||||||
|
|
||||||
endmenu
|
endmenu
|
||||||
|
|
||||||
|
config IOMMU_DEBUGFS
|
||||||
|
bool "Export IOMMU internals in DebugFS"
|
||||||
|
depends on DEBUG_FS
|
||||||
|
help
|
||||||
|
Allows exposure of IOMMU device internals. This option enables
|
||||||
|
the use of debugfs by IOMMU drivers as required. Devices can,
|
||||||
|
at initialization time, cause the IOMMU code to create a top-level
|
||||||
|
debug/iommu directory, and then populate a subdirectory with
|
||||||
|
entries as required.
|
||||||
|
|
||||||
config IOMMU_IOVA
|
config IOMMU_IOVA
|
||||||
tristate
|
tristate
|
||||||
|
|
||||||
|
|
|
@ -2,6 +2,7 @@
|
||||||
obj-$(CONFIG_IOMMU_API) += iommu.o
|
obj-$(CONFIG_IOMMU_API) += iommu.o
|
||||||
obj-$(CONFIG_IOMMU_API) += iommu-traces.o
|
obj-$(CONFIG_IOMMU_API) += iommu-traces.o
|
||||||
obj-$(CONFIG_IOMMU_API) += iommu-sysfs.o
|
obj-$(CONFIG_IOMMU_API) += iommu-sysfs.o
|
||||||
|
obj-$(CONFIG_IOMMU_DEBUGFS) += iommu-debugfs.o
|
||||||
obj-$(CONFIG_IOMMU_DMA) += dma-iommu.o
|
obj-$(CONFIG_IOMMU_DMA) += dma-iommu.o
|
||||||
obj-$(CONFIG_IOMMU_IO_PGTABLE) += io-pgtable.o
|
obj-$(CONFIG_IOMMU_IO_PGTABLE) += io-pgtable.o
|
||||||
obj-$(CONFIG_IOMMU_IO_PGTABLE_ARMV7S) += io-pgtable-arm-v7s.o
|
obj-$(CONFIG_IOMMU_IO_PGTABLE_ARMV7S) += io-pgtable-arm-v7s.o
|
||||||
|
|
66
drivers/iommu/iommu-debugfs.c
Normal file
66
drivers/iommu/iommu-debugfs.c
Normal file
|
@ -0,0 +1,66 @@
|
||||||
|
// SPDX-License-Identifier: GPL-2.0
|
||||||
|
/*
|
||||||
|
* IOMMU debugfs core infrastructure
|
||||||
|
*
|
||||||
|
* Copyright (C) 2018 Advanced Micro Devices, Inc.
|
||||||
|
*
|
||||||
|
* Author: Gary R Hook <gary.hook@amd.com>
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include <linux/pci.h>
|
||||||
|
#include <linux/iommu.h>
|
||||||
|
#include <linux/debugfs.h>
|
||||||
|
|
||||||
|
struct dentry *iommu_debugfs_dir;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* iommu_debugfs_setup - create the top-level iommu directory in debugfs
|
||||||
|
*
|
||||||
|
* Provide base enablement for using debugfs to expose internal data of an
|
||||||
|
* IOMMU driver. When called, this function creates the
|
||||||
|
* /sys/kernel/debug/iommu directory.
|
||||||
|
*
|
||||||
|
* Emit a strong warning at boot time to indicate that this feature is
|
||||||
|
* enabled.
|
||||||
|
*
|
||||||
|
* This function is called from iommu_init; drivers may then call
|
||||||
|
* iommu_debugfs_new_driver_dir() to instantiate a vendor-specific
|
||||||
|
* directory to be used to expose internal data.
|
||||||
|
*/
|
||||||
|
void iommu_debugfs_setup(void)
|
||||||
|
{
|
||||||
|
if (!iommu_debugfs_dir) {
|
||||||
|
iommu_debugfs_dir = debugfs_create_dir("iommu", NULL);
|
||||||
|
pr_warn("\n");
|
||||||
|
pr_warn("*************************************************************\n");
|
||||||
|
pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
|
||||||
|
pr_warn("** **\n");
|
||||||
|
pr_warn("** IOMMU DebugFS SUPPORT HAS BEEN ENABLED IN THIS KERNEL **\n");
|
||||||
|
pr_warn("** **\n");
|
||||||
|
pr_warn("** This means that this kernel is built to expose internal **\n");
|
||||||
|
pr_warn("** IOMMU data structures, which may compromise security on **\n");
|
||||||
|
pr_warn("** your system. **\n");
|
||||||
|
pr_warn("** **\n");
|
||||||
|
pr_warn("** If you see this message and you are not debugging the **\n");
|
||||||
|
pr_warn("** kernel, report this immediately to your vendor! **\n");
|
||||||
|
pr_warn("** **\n");
|
||||||
|
pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
|
||||||
|
pr_warn("*************************************************************\n");
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* iommu_debugfs_new_driver_dir - create a vendor directory under debugfs/iommu
|
||||||
|
* @vendor: name of the vendor-specific subdirectory to create
|
||||||
|
*
|
||||||
|
* This function is called by an IOMMU driver to create the top-level debugfs
|
||||||
|
* directory for that driver.
|
||||||
|
*
|
||||||
|
* Return: upon success, a pointer to the dentry for the new directory.
|
||||||
|
* NULL in case of failure.
|
||||||
|
*/
|
||||||
|
struct dentry *iommu_debugfs_new_driver_dir(const char *vendor)
|
||||||
|
{
|
||||||
|
return debugfs_create_dir(vendor, iommu_debugfs_dir);
|
||||||
|
}
|
||||||
|
EXPORT_SYMBOL_GPL(iommu_debugfs_new_driver_dir);
|
|
@ -1748,6 +1748,8 @@ static int __init iommu_init(void)
|
||||||
NULL, kernel_kobj);
|
NULL, kernel_kobj);
|
||||||
BUG_ON(!iommu_group_kset);
|
BUG_ON(!iommu_group_kset);
|
||||||
|
|
||||||
|
iommu_debugfs_setup();
|
||||||
|
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
core_initcall(iommu_init);
|
core_initcall(iommu_init);
|
||||||
|
|
|
@ -698,4 +698,11 @@ const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode)
|
||||||
|
|
||||||
#endif /* CONFIG_IOMMU_API */
|
#endif /* CONFIG_IOMMU_API */
|
||||||
|
|
||||||
|
#ifdef CONFIG_IOMMU_DEBUGFS
|
||||||
|
extern struct dentry *iommu_debugfs_dir;
|
||||||
|
void iommu_debugfs_setup(void);
|
||||||
|
#else
|
||||||
|
static inline void iommu_debugfs_setup(void) {}
|
||||||
|
#endif
|
||||||
|
|
||||||
#endif /* __LINUX_IOMMU_H */
|
#endif /* __LINUX_IOMMU_H */
|
||||||
|
|
Loading…
Reference in a new issue