x86/IOMMU: address violations of MISRA C:2012 Rule 14.4

The xen sources contain violations of MISRA C:2012 Rule 14.4 whose
headline states:
"The controlling expression of an if statement and the controlling
expression of an iteration-statement shall have essentially Boolean type".

Add comparisons to avoid using enum constants as controlling expressions
to comply with Rule 14.4.

Amend the comment in the enum definition to reflect the fact that
boolean uses of iommu_intremap are no longer allowed.

No functional change.

Signed-off-by: Maria Celeste Cesario <maria.celeste.cesario@bugseng.com>
Signed-off-by: Simone Ballarin <simone.ballarin@bugseng.com>
Signed-off-by: Nicola Vetrini <nicola.vetrini@bugseng.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

diff --git a/xen/arch/x86/hpet.c b/xen/arch/x86/hpet.c
index 0759eae055cecd8b795c2d665cc2870dec74cd7a..2f54d31889668ee6f51a4eee086905b2d5cba317 100644 (file)
--- a/xen/arch/x86/hpet.c
+++ b/xen/arch/x86/hpet.c
@@ -278,7 +278,7 @@ static int hpet_msi_write(struct hpet_event_channel *ch, struct msi_msg *msg)
 {
     ch->msi.msg = *msg;
 
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
     {
         int rc = iommu_update_ire_from_msi(&ch->msi, msg);
 
@@ -352,7 +352,7 @@ static int __init hpet_setup_msi_irq(struct hpet_event_channel *ch)
     u32 cfg = hpet_read32(HPET_Tn_CFG(ch->idx));
     irq_desc_t *desc = irq_to_desc(ch->msi.irq);
 
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
     {
         ch->msi.hpet_id = hpet_blockid;
         ret = iommu_setup_hpet_msi(&ch->msi);
@@ -371,7 +371,7 @@ static int __init hpet_setup_msi_irq(struct hpet_event_channel *ch)
         ret = __hpet_setup_msi_irq(desc);
     if ( ret < 0 )
     {
-        if ( iommu_intremap )
+        if ( iommu_intremap != iommu_intremap_off )
             iommu_update_ire_from_msi(&ch->msi, NULL);
         return ret;
     }

diff --git a/xen/arch/x86/msi.c b/xen/arch/x86/msi.c
index e721aaf5c0011398011373eb11bb26466e354da2..3009ce109f5e2750641b41abb9f4a59f937a5bb8 100644 (file)
--- a/xen/arch/x86/msi.c
+++ b/xen/arch/x86/msi.c
@@ -189,7 +189,7 @@ static int write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 {
     entry->msg = *msg;
 
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
     {
         int rc;
 
@@ -555,7 +555,7 @@ int msi_free_irq(struct msi_desc *entry)
             destroy_irq(entry[nr].irq);
 
         /* Free the unused IRTE if intr remap enabled */
-        if ( iommu_intremap )
+        if ( iommu_intremap != iommu_intremap_off )
             iommu_update_ire_from_msi(entry + nr, NULL);
     }
 

diff --git a/xen/drivers/passthrough/amd/iommu_init.c b/xen/drivers/passthrough/amd/iommu_init.c
index 358c8cbad99c3b66ac88d4a34bee3231491ed2f4..6c0dc2d5cb6996a13644fff1407d414525e47eee 100644 (file)
--- a/xen/drivers/passthrough/amd/iommu_init.c
+++ b/xen/drivers/passthrough/amd/iommu_init.c
@@ -1483,7 +1483,7 @@ int __init amd_iommu_init(bool xt)
             goto error_out;
     }
 
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
         register_keyhandler('V', &amd_iommu_dump_intremap_tables,
                             "dump IOMMU intremap tables", 0);
 
@@ -1501,7 +1501,7 @@ int __init amd_iommu_init_late(void)
 
     /* Further initialize the device table(s). */
     pci_init = true;
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
         rc = iterate_ivrs_mappings(amd_iommu_setup_device_table);
 
     for_each_amd_iommu ( iommu )

diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index c7110af7c9cde61d84fc1c69fbb7f3c8e2be54b8..e13be244c1305735fa5b0b27df2d256896e9f2aa 100644 (file)
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -2540,7 +2540,7 @@ static int __must_check init_vtd_hw(bool resume)
     /*
      * Enable interrupt remapping
      */  
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
     {
         int apic;
         for ( apic = 0; apic < nr_ioapics; apic++ )
@@ -2556,7 +2556,7 @@ static int __must_check init_vtd_hw(bool resume)
             }
         }
     }
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
     {
         for_each_drhd_unit ( drhd )
         {

diff --git a/xen/drivers/passthrough/vtd/quirks.c b/xen/drivers/passthrough/vtd/quirks.c
index 5a56565ea883cb4d5123baed557b4bb9db3f79a8..950dcd56ef8af4775206aa638e1db439f3fe3525 100644 (file)
--- a/xen/drivers/passthrough/vtd/quirks.c
+++ b/xen/drivers/passthrough/vtd/quirks.c
@@ -392,7 +392,7 @@ void __init platform_quirks_init(void)
     map_igd_reg();
 
     /* Tylersburg interrupt remap quirk */
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
         tylersburg_intremap_quirk();
 }
 

diff --git a/xen/include/xen/iommu.h b/xen/include/xen/iommu.h
index 92db6f124f13da2f330909bf3f9ee9896331dcf8..442ae5322d341041acaebccac666fd0c3534fb31 100644 (file)
--- a/xen/include/xen/iommu.h
+++ b/xen/include/xen/iommu.h
@@ -60,10 +60,6 @@ extern uint8_t iommu_quarantine;
 
 #ifdef CONFIG_X86
 extern enum __packed iommu_intremap {
-   /*
-    * In order to allow traditional boolean uses of the iommu_intremap
-    * variable, the "off" value has to come first (yielding a value of zero).
-    */
    iommu_intremap_off,
    /*
     * Interrupt remapping enabled, but only able to generate interrupts