[RFC PATCH 09/10] [RFC only] xen: iommu: remove last pcidevs_lock() calls in iommu

[Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>]

There are number of cases where pcidevs_lock() is used to protect
something that is not related to PCI devices per se.

Probably pcidev_lock in these places should be replaced with some
other lock.

This patch is not intended to be merged and is present only to discuss
this use of pcidevs_lock()

Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
---
 xen/drivers/passthrough/vtd/intremap.c | 2 --
 xen/drivers/passthrough/vtd/iommu.c    | 5 -----
 xen/drivers/passthrough/x86/iommu.c    | 5 -----
 3 files changed, 12 deletions(-)

diff --git a/xen/drivers/passthrough/vtd/intremap.c b/xen/drivers/passthrough/vtd/intremap.c
index 1512e4866b..44e3b72f91 100644
--- a/xen/drivers/passthrough/vtd/intremap.c
+++ b/xen/drivers/passthrough/vtd/intremap.c
@@ -893,8 +893,6 @@ int pi_update_irte(const struct pi_desc *pi_desc, const struct pirq *pirq,
 
     spin_unlock_irq(&desc->lock);
 
-    ASSERT(pcidevs_locked());
-
     return msi_msg_write_remap_rte(msi_desc, &msi_desc->msg);
 
  unlock_out:
diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c
index 87868188b7..9d258d154d 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -127,8 +127,6 @@ static int context_set_domain_id(struct context_entry *context,
 {
     unsigned int i;
 
-    ASSERT(pcidevs_locked());
-
     if ( domid_mapping(iommu) )
     {
         unsigned int nr_dom = cap_ndoms(iommu->cap);
@@ -1882,7 +1880,6 @@ int domain_context_unmap_one(
     int iommu_domid, rc, ret;
     bool_t flush_dev_iotlb;
 
-    ASSERT(pcidevs_locked());
     spin_lock(&iommu->lock);
 
     maddr = bus_to_context_maddr(iommu, bus);
@@ -2601,7 +2598,6 @@ static void __hwdom_init setup_hwdom_rmrr(struct domain *d)
     u16 bdf;
     int ret, i;
 
-    pcidevs_lock();
     for_each_rmrr_device ( rmrr, bdf, i )
     {
         /*
@@ -2616,7 +2612,6 @@ static void __hwdom_init setup_hwdom_rmrr(struct domain *d)
             dprintk(XENLOG_ERR VTDPREFIX,
                      "IOMMU: mapping reserved region failed\n");
     }
-    pcidevs_unlock();
 }
 
 static struct iommu_state {
diff --git a/xen/drivers/passthrough/x86/iommu.c b/xen/drivers/passthrough/x86/iommu.c
index f671b0f2bb..4e94ad15df 100644
--- a/xen/drivers/passthrough/x86/iommu.c
+++ b/xen/drivers/passthrough/x86/iommu.c
@@ -207,7 +207,6 @@ int iommu_identity_mapping(struct domain *d, p2m_access_t p2ma,
     struct identity_map *map;
     struct domain_iommu *hd = dom_iommu(d);
 
-    ASSERT(pcidevs_locked());
     ASSERT(base < end);
 
     /*
@@ -479,8 +478,6 @@ domid_t iommu_alloc_domid(unsigned long *map)
     static unsigned int start;
     unsigned int idx = find_next_zero_bit(map, UINT16_MAX - DOMID_MASK, start);
 
-    ASSERT(pcidevs_locked());
-
     if ( idx >= UINT16_MAX - DOMID_MASK )
         idx = find_first_zero_bit(map, UINT16_MAX - DOMID_MASK);
     if ( idx >= UINT16_MAX - DOMID_MASK )
@@ -495,8 +492,6 @@ domid_t iommu_alloc_domid(unsigned long *map)
 
 void iommu_free_domid(domid_t domid, unsigned long *map)
 {
-    ASSERT(pcidevs_locked());
-
     if ( domid == DOMID_INVALID )
         return;
 
-- 
2.36.1