[PATCH v2] xen/serial: Don't leak memory mapping if the serial initialization has failed

[Julien Grall <julien.grall@linaro.org>]

The memory mapping is leaking when the serial driver failed to retrieve
the IRQ. We can safely move the call to ioremap after.

Also use ioremap_cache instead of ioremap_attr in some serial drivers.

Signed-off-by: Julien Grall <julien.grall@linaro.org>

---

Ian, I have dropped your ack because the patch fundamentaly changed.

    Changes in v2:
        - s/ioremap_attr/ioremap_nocache
        - Move ioremap call after retrieve the IRQ
---
 xen/drivers/char/exynos4210-uart.c |   13 +++++++------
 xen/drivers/char/omap-uart.c       |   15 ++++++++-------
 xen/drivers/char/pl011.c           |   15 +++++++--------
 3 files changed, 22 insertions(+), 21 deletions(-)

diff --git a/xen/drivers/char/exynos4210-uart.c b/xen/drivers/char/exynos4210-uart.c
index 0619575..150d49b 100644
--- a/xen/drivers/char/exynos4210-uart.c
+++ b/xen/drivers/char/exynos4210-uart.c
@@ -334,12 +334,6 @@ static int __init exynos4210_uart_init(struct dt_device_node *dev,
         return res;
     }
 
-    uart->regs = ioremap_nocache(addr, size);
-    if ( !uart->regs )
-    {
-        early_printk("exynos4210: Unable to map the UART memory\n");
-        return -ENOMEM;
-    }
     res = dt_device_get_irq(dev, 0, &uart->irq);
     if ( res )
     {
@@ -347,6 +341,13 @@ static int __init exynos4210_uart_init(struct dt_device_node *dev,
         return res;
     }
 
+    uart->regs = ioremap_nocache(addr, size);
+    if ( !uart->regs )
+    {
+        early_printk("exynos4210: Unable to map the UART memory\n");
+        return -ENOMEM;
+    }
+
     uart->vuart.base_addr = addr;
     uart->vuart.size = size;
     uart->vuart.data_off = UTXH;
diff --git a/xen/drivers/char/omap-uart.c b/xen/drivers/char/omap-uart.c
index c1580ef..b29f610 100644
--- a/xen/drivers/char/omap-uart.c
+++ b/xen/drivers/char/omap-uart.c
@@ -326,13 +326,6 @@ static int __init omap_uart_init(struct dt_device_node *dev,
         return res;
     }
 
-    uart->regs = ioremap_attr(addr, size, PAGE_HYPERVISOR_NOCACHE);
-    if ( !uart->regs )
-    {
-        early_printk("omap-uart: Unable to map the UART memory\n");
-        return -ENOMEM;
-    }
-
     res = dt_device_get_irq(dev, 0, &uart->irq);
     if ( res )
     {
@@ -340,6 +333,14 @@ static int __init omap_uart_init(struct dt_device_node *dev,
         return res;
     }
 
+    uart->regs = ioremap_nocache(addr, size);
+    if ( !uart->regs )
+    {
+        early_printk("omap-uart: Unable to map the UART memory\n");
+        return -ENOMEM;
+    }
+
+
     uart->vuart.base_addr = addr;
     uart->vuart.size = size;
     uart->vuart.data_off = UART_THR;
diff --git a/xen/drivers/char/pl011.c b/xen/drivers/char/pl011.c
index fd82511..fe99af6 100644
--- a/xen/drivers/char/pl011.c
+++ b/xen/drivers/char/pl011.c
@@ -248,14 +248,6 @@ static int __init pl011_uart_init(struct dt_device_node *dev,
         return res;
     }
 
-    uart->regs = ioremap_attr(addr, size, PAGE_HYPERVISOR_NOCACHE);
-    if ( !uart->regs )
-    {
-        early_printk("pl011: Unable to map the UART memory\n");
-
-        return -ENOMEM;
-    }
-
     res = dt_device_get_irq(dev, 0, &uart->irq);
     if ( res )
     {
@@ -263,6 +255,13 @@ static int __init pl011_uart_init(struct dt_device_node *dev,
         return res;
     }
 
+    uart->regs = ioremap_nocache(addr, size);
+    if ( !uart->regs )
+    {
+        early_printk("pl011: Unable to map the UART memory\n");
+        return -ENOMEM;
+    }
+
     uart->vuart.base_addr = addr;
     uart->vuart.size = size;
     uart->vuart.data_off = DR;
-- 
1.7.10.4