[PATCH] powerpc/xive: Add some error handling code to 'xive_spapr_init()'

[Christophe JAILLET]

'xive_irq_bitmap_add()' can return -ENOMEM.
In this case, we should free the memory already allocated and return
'false' to the caller.

Also add an error path which undoes the 'tima = ioremap(...)'

Signed-off-by: Christophe JAILLET <christophe.jail...@wanadoo.fr>
---
NOT compile tested (I don't have a cross compiler and won't install one).
So if some correction or improvement are needed, feel free to propose and
commit it directly.
---
 arch/powerpc/sysdev/xive/spapr.c | 36 +++++++++++++++++++++++++-------
 1 file changed, 28 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/sysdev/xive/spapr.c b/arch/powerpc/sysdev/xive/spapr.c
index 52198131c75e..b3ae0b76c433 100644
--- a/arch/powerpc/sysdev/xive/spapr.c
+++ b/arch/powerpc/sysdev/xive/spapr.c
@@ -64,6 +64,17 @@ static int xive_irq_bitmap_add(int base, int count)
        return 0;
 }
 
+static void xive_irq_bitmap_remove_all(void)
+{
+       struct xive_irq_bitmap *xibm, *tmp;
+
+       list_for_each_entry_safe(xibm, tmp, &xive_irq_bitmaps, list) {
+               list_del(&xibm->list);
+               kfree(xibm->bitmap);
+               kfree(xibm);
+       }
+}
+
 static int __xive_irq_bitmap_alloc(struct xive_irq_bitmap *xibm)
 {
        int irq;
@@ -723,7 +734,7 @@ bool __init xive_spapr_init(void)
        u32 val;
        u32 len;
        const __be32 *reg;
-       int i;
+       int i, err;
 
        if (xive_spapr_disabled())
                return false;
@@ -748,23 +759,26 @@ bool __init xive_spapr_init(void)
        }
 
        if (!xive_get_max_prio(&max_prio))
-               return false;
+               goto err_unmap;
 
        /* Feed the IRQ number allocator with the ranges given in the DT */
        reg = of_get_property(np, "ibm,xive-lisn-ranges", &len);
        if (!reg) {
                pr_err("Failed to read 'ibm,xive-lisn-ranges' property\n");
-               return false;
+               goto err_unmap;
        }
 
        if (len % (2 * sizeof(u32)) != 0) {
                pr_err("invalid 'ibm,xive-lisn-ranges' property\n");
-               return false;
+               goto err_unmap;
        }
 
-       for (i = 0; i < len / (2 * sizeof(u32)); i++, reg += 2)
-               xive_irq_bitmap_add(be32_to_cpu(reg[0]),
-                                   be32_to_cpu(reg[1]));
+       for (i = 0; i < len / (2 * sizeof(u32)); i++, reg += 2) {
+               err = xive_irq_bitmap_add(be32_to_cpu(reg[0]),
+                                         be32_to_cpu(reg[1]));
+               if (err < 0)
+                       goto err_mem_free;
+       }
 
        /* Iterate the EQ sizes and pick one */
        of_property_for_each_u32(np, "ibm,xive-eq-sizes", prop, reg, val) {
@@ -775,8 +789,14 @@ bool __init xive_spapr_init(void)
 
        /* Initialize XIVE core with our backend */
        if (!xive_core_init(&xive_spapr_ops, tima, TM_QW1_OS, max_prio))
-               return false;
+               goto err_mem_free;
 
        pr_info("Using %dkB queues\n", 1 << (xive_queue_shift - 10));
        return true;
+
+err_mem_free:
+       xive_irq_bitmap_remove_all();
+err_unmap:
+       iounmap(tima);
+       return false;
 }
-- 
2.20.1