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author | Baoquan He <bhe@redhat.com> | 2017-08-09 16:33:38 +0800 |
---|---|---|
committer | Joerg Roedel <jroedel@suse.de> | 2017-08-15 18:14:39 +0200 |
commit | 3ac3e5ee5ed56b07448f295902e44916eb6979fc (patch) | |
tree | 1e6c62c314a67922605b7d959708c77157e13d50 /drivers/iommu/amd_iommu_init.c | |
parent | 45a01c42933b93e59811099f97aa4179d499a42c (diff) | |
download | op-kernel-dev-3ac3e5ee5ed56b07448f295902e44916eb6979fc.zip op-kernel-dev-3ac3e5ee5ed56b07448f295902e44916eb6979fc.tar.gz |
iommu/amd: Copy old trans table from old kernel
Here several things need be done:
- If iommu is pre-enabled in a normal kernel, just disable it and print
warning.
- If any one of IOMMUs is not pre-enabled in kdump kernel, just continue
as it does in normal kernel.
- If failed to copy dev table of old kernel, continue to proceed as
it does in normal kernel.
- Only if all IOMMUs are pre-enabled and copy dev table is done well, free
the dev table allocated in early_amd_iommu_init() and make amd_iommu_dev_table
point to the copied one.
- Disable and Re-enable event/cmd buffer, install the copied DTE table
to reg, and detect and enable guest vapic.
- Flush all caches
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/amd_iommu_init.c')
-rw-r--r-- | drivers/iommu/amd_iommu_init.c | 59 |
1 files changed, 51 insertions, 8 deletions
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c index e285720..959c25d 100644 --- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -37,6 +37,7 @@ #include <asm/io_apic.h> #include <asm/irq_remapping.h> +#include <linux/crash_dump.h> #include "amd_iommu_proto.h" #include "amd_iommu_types.h" #include "irq_remapping.h" @@ -262,6 +263,8 @@ static int amd_iommu_enable_interrupts(void); static int __init iommu_go_to_state(enum iommu_init_state state); static void init_device_table_dma(void); +static bool __initdata amd_iommu_pre_enabled = true; + bool translation_pre_enabled(struct amd_iommu *iommu) { return (iommu->flags & AMD_IOMMU_FLAG_TRANS_PRE_ENABLED); @@ -857,6 +860,8 @@ static bool copy_device_table(void) u16 dom_id, dte_v; gfp_t gfp_flag; + if (!amd_iommu_pre_enabled) + return false; pr_warn("Translation is already enabled - trying to copy translation structures\n"); for_each_iommu(iommu) { @@ -1496,9 +1501,14 @@ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h) iommu->int_enabled = false; init_translation_status(iommu); - - if (translation_pre_enabled(iommu)) - pr_warn("Translation is already enabled - trying to copy translation structures\n"); + if (translation_pre_enabled(iommu) && !is_kdump_kernel()) { + iommu_disable(iommu); + clear_translation_pre_enabled(iommu); + pr_warn("Translation was enabled for IOMMU:%d but we are not in kdump mode\n", + iommu->index); + } + if (amd_iommu_pre_enabled) + amd_iommu_pre_enabled = translation_pre_enabled(iommu); ret = init_iommu_from_acpi(iommu, h); if (ret) @@ -1993,8 +2003,7 @@ static int __init init_memory_definitions(struct acpi_table_header *table) } /* - * Init the device table to not allow DMA access for devices and - * suppress all page faults + * Init the device table to not allow DMA access for devices */ static void init_device_table_dma(void) { @@ -2130,14 +2139,48 @@ static void early_enable_iommu(struct amd_iommu *iommu) /* * This function finally enables all IOMMUs found in the system after - * they have been initialized + * they have been initialized. + * + * Or if in kdump kernel and IOMMUs are all pre-enabled, try to copy + * the old content of device table entries. Not this case or copy failed, + * just continue as normal kernel does. */ static void early_enable_iommus(void) { struct amd_iommu *iommu; - for_each_iommu(iommu) - early_enable_iommu(iommu); + + if (!copy_device_table()) { + /* + * If come here because of failure in copying device table from old + * kernel with all IOMMUs enabled, print error message and try to + * free allocated old_dev_tbl_cpy. + */ + if (amd_iommu_pre_enabled) + pr_err("Failed to copy DEV table from previous kernel.\n"); + if (old_dev_tbl_cpy != NULL) + free_pages((unsigned long)old_dev_tbl_cpy, + get_order(dev_table_size)); + + for_each_iommu(iommu) { + clear_translation_pre_enabled(iommu); + early_enable_iommu(iommu); + } + } else { + pr_info("Copied DEV table from previous kernel.\n"); + free_pages((unsigned long)amd_iommu_dev_table, + get_order(dev_table_size)); + amd_iommu_dev_table = old_dev_tbl_cpy; + for_each_iommu(iommu) { + iommu_disable_command_buffer(iommu); + iommu_disable_event_buffer(iommu); + iommu_enable_command_buffer(iommu); + iommu_enable_event_buffer(iommu); + iommu_enable_ga(iommu); + iommu_set_device_table(iommu); + iommu_flush_all_caches(iommu); + } + } #ifdef CONFIG_IRQ_REMAP if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir)) |