Messages in this thread Patch in this message | | | From | Jingqi Liu <> | Subject | [PATH v3 2/3] iommu/vt-d: debugfs: Create/remove debugfs file per {device, pasid} | Date | Wed, 27 Sep 2023 23:15:35 +0800 |
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Add a debugfs directory per pair of {device, pasid} if the mappings of its page table are created and destroyed by the iommu_map/unmap() interfaces. i.e. /sys/kernel/debug/iommu/intel/<device source id>/<pasid>. Create a debugfs file in the directory for users to dump the page table corresponding to {device, pasid}. e.g. /sys/kernel/debug/iommu/intel/0000:00:02.0/0/domain_translation_struct.
When attaching device without pasid, create a debugfs file with PASID#0, i.e. RID_PASID. When attaching a domain to a pasid of device, create a debugfs file with the specified pasid.
When detaching without pasid, remove the directory and file for PASID#0. When detaching with pasid, remove the debugfs directory and file of the specified pasid. Remove the entire debugfs directory of the specified device for releasing device. e.g. /sys/kernel/debug/iommu/intel/0000:00:01.0
Signed-off-by: Jingqi Liu <Jingqi.liu@intel.com> --- drivers/iommu/intel/debugfs.c | 133 ++++++++++++++++++++++++++++++++-- drivers/iommu/intel/iommu.c | 29 ++++++++ drivers/iommu/intel/iommu.h | 12 +++ 3 files changed, 169 insertions(+), 5 deletions(-)
diff --git a/drivers/iommu/intel/debugfs.c b/drivers/iommu/intel/debugfs.c index e2a3c37943a0..50dea53ba87c 100644 --- a/drivers/iommu/intel/debugfs.c +++ b/drivers/iommu/intel/debugfs.c @@ -32,6 +32,11 @@ struct iommu_regset { const char *regs; }; +struct show_domain_info { + struct device *dev; + ioasid_t pasid; +}; + #define DEBUG_BUFFER_SIZE 1024 static char debug_buf[DEBUG_BUFFER_SIZE]; @@ -111,6 +116,8 @@ static const struct iommu_regset iommu_regs_64[] = { IOMMU_REGSET_ENTRY(VCRSP), }; +static struct dentry *intel_iommu_debug; + static int iommu_regset_show(struct seq_file *m, void *unused) { struct dmar_drhd_unit *drhd; @@ -673,16 +680,12 @@ static const struct file_operations dmar_perf_latency_fops = { void __init intel_iommu_debugfs_init(void) { - struct dentry *intel_iommu_debug = debugfs_create_dir("intel", - iommu_debugfs_dir); + intel_iommu_debug = debugfs_create_dir("intel", iommu_debugfs_dir); debugfs_create_file("iommu_regset", 0444, intel_iommu_debug, NULL, &iommu_regset_fops); debugfs_create_file("dmar_translation_struct", 0444, intel_iommu_debug, NULL, &dmar_translation_struct_fops); - debugfs_create_file("domain_translation_struct", 0444, - intel_iommu_debug, NULL, - &domain_translation_struct_fops); debugfs_create_file("invalidation_queue", 0444, intel_iommu_debug, NULL, &invalidation_queue_fops); #ifdef CONFIG_IRQ_REMAP @@ -692,3 +695,123 @@ void __init intel_iommu_debugfs_init(void) debugfs_create_file("dmar_perf_latency", 0644, intel_iommu_debug, NULL, &dmar_perf_latency_fops); } + +/* Create a debugfs directory for each device. */ +void intel_iommu_debugfs_create_dev(struct device *dev) +{ + struct dentry *dev_dir; + + dev_dir = debugfs_lookup(dev_name(dev), intel_iommu_debug); + if (!dev_dir) { + dev_dir = debugfs_create_dir(dev_name(dev), intel_iommu_debug); + if (IS_ERR(dev_dir)) + pr_info("%s: Failed to create debugfs directory.\n", + dev_name(dev)); + } else + dput(dev_dir); +} + +void intel_iommu_debugfs_remove_dev(struct device *dev) +{ + struct dentry *dev_dir, *sub_dir, *dentry; + struct list_head *plist; + + dev_dir = debugfs_lookup(dev_name(dev), intel_iommu_debug); + if (!dev_dir) + return; + + list_for_each(plist, &(dev_dir->d_subdirs)) { + sub_dir = list_entry(plist, struct dentry, d_child); + if(sub_dir) { + dentry = debugfs_lookup("domain_translation_struct", + sub_dir); + if (!dentry) + continue; + + if (dentry->d_inode->i_private) + kfree(dentry->d_inode->i_private); + + dput(dentry); + } + } + + debugfs_remove_recursive(dev_dir); + dput(dev_dir); +} + +/* + * Create a debugfs directory per pair of {device, pasid}, + * then create the corresponding debugfs file in this directory + * for user to dump its page table. e.g. + * /sys/kernel/debug/iommu/intel/0000:00:01.0/0/domain_translation_struct + */ +void intel_iommu_debugfs_create_dev_pasid(struct iommu_domain *domain, + struct device *dev, u32 pasid) +{ + struct dentry *dev_dir, *pasid_dir; + struct show_domain_info *sinfo; + char dir_name[10]; + + /* + * The debugfs only dumps the page tables whose mappings are created + * and destroyed by the iommu_map/unmap() interfaces. Check the + * mapping type of the domain before creating debugfs directory. + */ + if (!domain || !(domain->type & __IOMMU_DOMAIN_PAGING)) + return; + + dev_dir = debugfs_lookup(dev_name(dev), intel_iommu_debug); + if (!dev_dir) + return; + + sprintf(dir_name, "%x", pasid); + pasid_dir = debugfs_create_dir(dir_name, dev_dir); + if (IS_ERR(pasid_dir)) + goto dput_out; + + sinfo = kzalloc(sizeof(*sinfo), GFP_KERNEL); + if (!sinfo) + goto dput_out; + + sinfo->dev = dev; + sinfo->pasid = pasid; + debugfs_create_file("domain_translation_struct", 0444, + pasid_dir, sinfo, + &domain_translation_struct_fops); +dput_out: + dput(dev_dir); +} + +/* + * Remove the debugfs directory and file corresponding to each pair of + * {device, pasid}. + */ +void intel_iommu_debugfs_remove_dev_pasid(struct device *dev, u32 pasid) +{ + struct dentry *dev_dir, *pasid_dir, *dentry; + char dir_name[10]; + + dev_dir = debugfs_lookup(dev_name(dev), intel_iommu_debug); + if (!dev_dir) + return; + + sprintf(dir_name, "%x", pasid); + pasid_dir = debugfs_lookup(dir_name, dev_dir); + if (!pasid_dir) + goto dput_dev; + + dentry = debugfs_lookup("domain_translation_struct", pasid_dir); + if (!dentry) + goto dput_pasid; + + if (dentry->d_inode->i_private) + kfree(dentry->d_inode->i_private); + + debugfs_remove_recursive(pasid_dir); + + dput(dentry); +dput_pasid: + dput(pasid_dir); +dput_dev: + dput(dev_dir); +} diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index dd8ff358867d..af9c989035a2 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -2488,6 +2488,13 @@ static int dmar_domain_attach_device(struct dmar_domain *domain, iommu_enable_pci_caps(info); + /* + * Create a debugfs directory specified by RID_PASID + * in the debugfs device directory. + */ + intel_iommu_debugfs_create_dev_pasid(&info->domain->domain, + dev, IOMMU_NO_PASID); + return 0; } @@ -3997,6 +4004,12 @@ static void device_block_translation(struct device *dev) domain_detach_iommu(info->domain, iommu); info->domain = NULL; + + /* + * Remove the debugfs directory specified by RID_PASID + * in the device debugfs directory. + */ + intel_iommu_debugfs_remove_dev_pasid(dev, IOMMU_NO_PASID); } static int md_domain_init(struct dmar_domain *domain, int guest_width) @@ -4424,6 +4437,9 @@ static struct iommu_device *intel_iommu_probe_device(struct device *dev) } } + /* Create a debugfs directory per device. */ + intel_iommu_debugfs_create_dev(dev); + return &iommu->iommu; } @@ -4436,6 +4452,7 @@ static void intel_iommu_release_device(struct device *dev) dev_iommu_priv_set(dev, NULL); kfree(info); set_dma_ops(dev, NULL); + intel_iommu_debugfs_remove_dev(dev); } static void intel_iommu_probe_finalize(struct device *dev) @@ -4729,6 +4746,12 @@ static void intel_iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid) out_tear_down: intel_pasid_tear_down_entry(iommu, dev, pasid, false); intel_drain_pasid_prq(dev, pasid); + + /* + * Remove the debugfs directory of the specified pasid + * in the device debugfs directory. + */ + intel_iommu_debugfs_remove_dev_pasid(dev, pasid); } static int intel_iommu_set_dev_pasid(struct iommu_domain *domain, @@ -4777,6 +4800,12 @@ static int intel_iommu_set_dev_pasid(struct iommu_domain *domain, list_add(&dev_pasid->link_domain, &dmar_domain->dev_pasids); spin_unlock_irqrestore(&dmar_domain->lock, flags); + /* + * Create a debugfs directory with specified pasid + * in the debugfs device directory. + */ + intel_iommu_debugfs_create_dev_pasid(domain, dev, pasid); + return 0; out_detach_iommu: domain_detach_iommu(dmar_domain, iommu); diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h index c18fb699c87a..f1c27e928886 100644 --- a/drivers/iommu/intel/iommu.h +++ b/drivers/iommu/intel/iommu.h @@ -883,8 +883,20 @@ static inline void intel_svm_remove_dev_pasid(struct device *dev, ioasid_t pasid #ifdef CONFIG_INTEL_IOMMU_DEBUGFS void intel_iommu_debugfs_init(void); +void intel_iommu_debugfs_create_dev(struct device *dev); +void intel_iommu_debugfs_create_dev_pasid(struct iommu_domain *domain, + struct device *dev, u32 pasid); +void intel_iommu_debugfs_remove_dev(struct device *dev); +void intel_iommu_debugfs_remove_dev_pasid(struct device *dev, u32 pasid); #else static inline void intel_iommu_debugfs_init(void) {} +static inline void intel_iommu_debugfs_create_dev(struct device *dev) {} +static inline +void intel_iommu_debugfs_create_dev_pasid(struct iommu_domain *domain, + struct device *dev, u32 pasid) {} +static inline void intel_iommu_debugfs_remove_dev(struct device *dev) {} +static inline +void intel_iommu_debugfs_remove_dev_pasid(struct device *dev, u32 pasid) {} #endif /* CONFIG_INTEL_IOMMU_DEBUGFS */ extern const struct attribute_group *intel_iommu_groups[]; -- 2.21.3
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