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authorChris Wright <chrisw@sous-sol.org>2010-04-02 18:27:53 -0700
committerJoerg Roedel <joerg.roedel@amd.com>2010-04-07 11:51:15 +0200
commit549c90dc9a6d659e792b2a42a0930c7da015ea4a (patch)
treee0d0115631aa40eb45b58fb24bdcd399d2e17e47 /arch/x86
parent75f66533bc883f761a7adcab3281fe3323efbc90 (diff)
x86/amd-iommu: warn when issuing command to uninitialized cmd buffer
To catch future potential issues we can add a warning whenever we issue a command before the command buffer is fully initialized. Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/include/asm/amd_iommu_types.h1
-rw-r--r--arch/x86/kernel/amd_iommu.c1
-rw-r--r--arch/x86/kernel/amd_iommu_init.c5
3 files changed, 5 insertions, 2 deletions
diff --git a/arch/x86/include/asm/amd_iommu_types.h b/arch/x86/include/asm/amd_iommu_types.h
index 5e46e78f3b1..86a0ff0aeac 100644
--- a/arch/x86/include/asm/amd_iommu_types.h
+++ b/arch/x86/include/asm/amd_iommu_types.h
@@ -141,6 +141,7 @@
/* constants to configure the command buffer */
#define CMD_BUFFER_SIZE 8192
+#define CMD_BUFFER_UNINITIALIZED 1
#define CMD_BUFFER_ENTRIES 512
#define MMIO_CMD_SIZE_SHIFT 56
#define MMIO_CMD_SIZE_512 (0x9ULL << MMIO_CMD_SIZE_SHIFT)
diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index b06f29e275e..71dfc0af8e5 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -392,6 +392,7 @@ static int __iommu_queue_command(struct amd_iommu *iommu, struct iommu_cmd *cmd)
u32 tail, head;
u8 *target;
+ WARN_ON(iommu->cmd_buf_size & CMD_BUFFER_UNINITIALIZED);
tail = readl(iommu->mmio_base + MMIO_CMD_TAIL_OFFSET);
target = iommu->cmd_buf + tail;
memcpy_toio(target, cmd, sizeof(*cmd));
diff --git a/arch/x86/kernel/amd_iommu_init.c b/arch/x86/kernel/amd_iommu_init.c
index 8975965f3e6..5edf41c7127 100644
--- a/arch/x86/kernel/amd_iommu_init.c
+++ b/arch/x86/kernel/amd_iommu_init.c
@@ -438,7 +438,7 @@ static u8 * __init alloc_command_buffer(struct amd_iommu *iommu)
if (cmd_buf == NULL)
return NULL;
- iommu->cmd_buf_size = CMD_BUFFER_SIZE;
+ iommu->cmd_buf_size = CMD_BUFFER_SIZE | CMD_BUFFER_UNINITIALIZED;
return cmd_buf;
}
@@ -474,12 +474,13 @@ static void iommu_enable_command_buffer(struct amd_iommu *iommu)
&entry, sizeof(entry));
amd_iommu_reset_cmd_buffer(iommu);
+ iommu->cmd_buf_size &= ~(CMD_BUFFER_UNINITIALIZED);
}
static void __init free_command_buffer(struct amd_iommu *iommu)
{
free_pages((unsigned long)iommu->cmd_buf,
- get_order(iommu->cmd_buf_size));
+ get_order(iommu->cmd_buf_size & ~(CMD_BUFFER_UNINITIALIZED)));
}
/* allocates the memory where the IOMMU will log its events to */