[xen staging] x86/IOMMU: address violations of MISRA C:2012 Rule 14.4

[patchbot@xxxxxxx]

commit fcefb2a2471a9b9d6997c62e9be461f17c390ebf
Author:     Maria Celeste Cesario <maria.celeste.cesario@xxxxxxxxxxx>
AuthorDate: Wed May 8 20:46:21 2024 +0200
Commit:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
CommitDate: Thu May 9 18:19:49 2024 +0100

    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@xxxxxxxxxxx>
    Signed-off-by: Simone Ballarin <simone.ballarin@xxxxxxxxxxx>
    Signed-off-by: Nicola Vetrini <nicola.vetrini@xxxxxxxxxxx>
    Reviewed-by: Stefano Stabellini <sstabellini@xxxxxxxxxx>
    Acked-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
 xen/arch/x86/hpet.c                      | 6 +++---
 xen/arch/x86/msi.c                       | 4 ++--
 xen/drivers/passthrough/amd/iommu_init.c | 4 ++--
 xen/drivers/passthrough/vtd/iommu.c      | 4 ++--
 xen/drivers/passthrough/vtd/quirks.c     | 2 +-
 xen/include/xen/iommu.h                  | 4 ----
 6 files changed, 10 insertions(+), 14 deletions(-)

diff --git a/xen/arch/x86/hpet.c b/xen/arch/x86/hpet.c
index 0759eae055..2f54d31889 100644
--- 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 e721aaf5c0..3009ce109f 100644
--- 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 358c8cbad9..6c0dc2d5cb 100644
--- 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 c7110af7c9..e13be244c1 100644
--- 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 5a56565ea8..950dcd56ef 100644
--- 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 92db6f124f..442ae5322d 100644
--- 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
--
generated by git-patchbot for /home/xen/git/xen.git#staging