[xen staging] PCI: drop pci_segments_init()

[patchbot@xxxxxxx]

commit 12e872ae3e7749098b0360af1c6a3118e03d8267
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Tue Mar 11 09:54:19 2025 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Tue Mar 11 09:54:19 2025 +0100

    PCI: drop pci_segments_init()
    
    Have callers invoke pci_add_segment() directly instead: With radix tree
    initialization moved out of the function, its name isn't quite
    describing anymore what it actually does.
    
    On x86 move the logic into __start_xen() itself, to reduce the risk of
    re-introducing ordering issues like the one which was addressed by
    26fe09e34566 ("radix-tree: introduce RADIX_TREE{,_INIT}()").
    
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
    Acked-by: Julien Grall <jgrall@xxxxxxxxxx>
---
 xen/arch/arm/pci/pci.c                | 3 ++-
 xen/arch/x86/setup.c                  | 7 +++++++
 xen/arch/x86/x86_64/mmconfig-shared.c | 2 --
 xen/drivers/passthrough/pci.c         | 6 ------
 xen/include/xen/pci.h                 | 1 -
 5 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/xen/arch/arm/pci/pci.c b/xen/arch/arm/pci/pci.c
index 78b97beaef..8d9692c92e 100644
--- a/xen/arch/arm/pci/pci.c
+++ b/xen/arch/arm/pci/pci.c
@@ -88,7 +88,8 @@ static int __init pci_init(void)
     if ( !pci_passthrough_enabled )
         return 0;
 
-    pci_segments_init();
+    if ( pci_add_segment(0) )
+        panic("Could not initialize PCI segment 0\n");
 
     if ( acpi_disabled )
         return dt_pci_init();
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index 143749e5da..4a32d84911 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -1899,6 +1899,13 @@ void asmlinkage __init noreturn __start_xen(void)
      */
     setup_system_domains();
 
+    /*
+     * Ahead of any ACPI table parsing make sure we have control structures
+     * for PCI segment 0.
+     */
+    if ( pci_add_segment(0) )
+        panic("Could not initialize PCI segment 0\n");
+
     /*
      * IOMMU-related ACPI table parsing has to happen before APIC probing, for
      * check_x2apic_preenabled() to be able to observe respective findings, in
diff --git a/xen/arch/x86/x86_64/mmconfig-shared.c 
b/xen/arch/x86/x86_64/mmconfig-shared.c
index 77ba1e28f1..f1a3d42c5b 100644
--- a/xen/arch/x86/x86_64/mmconfig-shared.c
+++ b/xen/arch/x86/x86_64/mmconfig-shared.c
@@ -402,8 +402,6 @@ void __init acpi_mmcfg_init(void)
 {
     bool valid = true;
 
-    pci_segments_init();
-
     /* MMCONFIG disabled */
     if ((pci_probe & PCI_PROBE_MMCONF) == 0)
         return;
diff --git a/xen/drivers/passthrough/pci.c b/xen/drivers/passthrough/pci.c
index ab25840e20..3edcfa8a04 100644
--- a/xen/drivers/passthrough/pci.c
+++ b/xen/drivers/passthrough/pci.c
@@ -127,12 +127,6 @@ static int pci_segments_iterate(
     return rc;
 }
 
-void __init pci_segments_init(void)
-{
-    if ( !alloc_pseg(0) )
-        panic("Could not initialize PCI segment 0\n");
-}
-
 int __init pci_add_segment(u16 seg)
 {
     return alloc_pseg(seg) ? 0 : -ENOMEM;
diff --git a/xen/include/xen/pci.h b/xen/include/xen/pci.h
index 4f12bcf089..ef60196653 100644
--- a/xen/include/xen/pci.h
+++ b/xen/include/xen/pci.h
@@ -219,7 +219,6 @@ void setup_hwdom_pci_devices(struct domain *d,
                              int (*handler)(uint8_t devfn,
                                             struct pci_dev *pdev));
 int pci_release_devices(struct domain *d);
-void pci_segments_init(void);
 int pci_add_segment(u16 seg);
 const unsigned long *pci_get_ro_map(u16 seg);
 int pci_add_device(u16 seg, u8 bus, u8 devfn,
--
generated by git-patchbot for /home/xen/git/xen.git#staging