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authorLinus Torvalds <torvalds@linux-foundation.org>2009-12-08 08:12:43 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2009-12-08 08:12:43 -0800
commit79c9601c2e0dbbe69895d302de4d19f3a31fbd30 (patch)
tree78d4be2df851b2b4106adcfd736622a90cecf9e9 /arch/arm/mm/vmregion.c
parent41440ffe21f29bdb985cab76b2d0b06d83e63b19 (diff)
parent3d14b5beba35250c548d3851a2b84fce742d8311 (diff)
Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (272 commits) Fix soc_common PCMCIA configuration ARM: 5827/1: SA1100: h3100/h3600: emit messages on failed gpio_request ARM: 5826/1: SA1100: h3100/h3600: always build htc-egpio driver ARM: 5825/1: SA1100: h3600: update defconfig ARM: 5824/1: SA1100: reuse h3600 PCMCIA driver on h3100 ARM: 5823/1: SA1100: h3100/h3600: add support for gpio-keys ARM: 5822/1: SA1100: h3100/h3600: clean up #includes ARM: 5821/1: SA1100: h3100/h3600: revise copyright boilerplates ARM: 5820/1: SA1100: h3100/h3600: split h3600.c ARM: 5819/1: SA1100: h3100/h3600: merge h3600.h and h3600_gpio.h into h3xxx.h ARM: 5818/1: SA1100: h3100/h3600: drop old GPIO definitions ARM: 5817/1: SA1100: h3100/h3600: configure all unused gpios as inputs ARM: 5816/1: SA1100: h3600: remove IRQ_GPIO_* definitions ARM: 5815/1: SA1100: h3100/h3600: remove now unused assign_h3600_egpio handlers ARM: 5814/1: SA1100: h3100/h3600: convert all users of assign_h3600_egpio to gpiolib ARM: 5813/1: SA1100: h3100/h3600: add htc-egpio driver ARM: 5812/1: SA1100: h3100/h3600: separate machine-specific LCD helpers ARM: 5811/2: pcmcia: convert sa1100_h3600 driver to gpiolib ARM: 5799/1: SA1100: h3600: stop setting direction for LCD pins ARM: 5798/1: SA1100: h3600: remove unused cruft from h3600.h ...
Diffstat (limited to 'arch/arm/mm/vmregion.c')
-rw-r--r--arch/arm/mm/vmregion.c131
1 files changed, 131 insertions, 0 deletions
diff --git a/arch/arm/mm/vmregion.c b/arch/arm/mm/vmregion.c
new file mode 100644
index 000000000000..19e09bdb1b8a
--- /dev/null
+++ b/arch/arm/mm/vmregion.c
@@ -0,0 +1,131 @@
+#include <linux/spinlock.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "vmregion.h"
+
+/*
+ * VM region handling support.
+ *
+ * This should become something generic, handling VM region allocations for
+ * vmalloc and similar (ioremap, module space, etc).
+ *
+ * I envisage vmalloc()'s supporting vm_struct becoming:
+ *
+ * struct vm_struct {
+ * struct vmregion region;
+ * unsigned long flags;
+ * struct page **pages;
+ * unsigned int nr_pages;
+ * unsigned long phys_addr;
+ * };
+ *
+ * get_vm_area() would then call vmregion_alloc with an appropriate
+ * struct vmregion head (eg):
+ *
+ * struct vmregion vmalloc_head = {
+ * .vm_list = LIST_HEAD_INIT(vmalloc_head.vm_list),
+ * .vm_start = VMALLOC_START,
+ * .vm_end = VMALLOC_END,
+ * };
+ *
+ * However, vmalloc_head.vm_start is variable (typically, it is dependent on
+ * the amount of RAM found at boot time.) I would imagine that get_vm_area()
+ * would have to initialise this each time prior to calling vmregion_alloc().
+ */
+
+struct arm_vmregion *
+arm_vmregion_alloc(struct arm_vmregion_head *head, size_t size, gfp_t gfp)
+{
+ unsigned long addr = head->vm_start, end = head->vm_end - size;
+ unsigned long flags;
+ struct arm_vmregion *c, *new;
+
+ if (head->vm_end - head->vm_start < size) {
+ printk(KERN_WARNING "%s: allocation too big (requested %#x)\n",
+ __func__, size);
+ goto out;
+ }
+
+ new = kmalloc(sizeof(struct arm_vmregion), gfp);
+ if (!new)
+ goto out;
+
+ spin_lock_irqsave(&head->vm_lock, flags);
+
+ list_for_each_entry(c, &head->vm_list, vm_list) {
+ if ((addr + size) < addr)
+ goto nospc;
+ if ((addr + size) <= c->vm_start)
+ goto found;
+ addr = c->vm_end;
+ if (addr > end)
+ goto nospc;
+ }
+
+ found:
+ /*
+ * Insert this entry _before_ the one we found.
+ */
+ list_add_tail(&new->vm_list, &c->vm_list);
+ new->vm_start = addr;
+ new->vm_end = addr + size;
+ new->vm_active = 1;
+
+ spin_unlock_irqrestore(&head->vm_lock, flags);
+ return new;
+
+ nospc:
+ spin_unlock_irqrestore(&head->vm_lock, flags);
+ kfree(new);
+ out:
+ return NULL;
+}
+
+static struct arm_vmregion *__arm_vmregion_find(struct arm_vmregion_head *head, unsigned long addr)
+{
+ struct arm_vmregion *c;
+
+ list_for_each_entry(c, &head->vm_list, vm_list) {
+ if (c->vm_active && c->vm_start == addr)
+ goto out;
+ }
+ c = NULL;
+ out:
+ return c;
+}
+
+struct arm_vmregion *arm_vmregion_find(struct arm_vmregion_head *head, unsigned long addr)
+{
+ struct arm_vmregion *c;
+ unsigned long flags;
+
+ spin_lock_irqsave(&head->vm_lock, flags);
+ c = __arm_vmregion_find(head, addr);
+ spin_unlock_irqrestore(&head->vm_lock, flags);
+ return c;
+}
+
+struct arm_vmregion *arm_vmregion_find_remove(struct arm_vmregion_head *head, unsigned long addr)
+{
+ struct arm_vmregion *c;
+ unsigned long flags;
+
+ spin_lock_irqsave(&head->vm_lock, flags);
+ c = __arm_vmregion_find(head, addr);
+ if (c)
+ c->vm_active = 0;
+ spin_unlock_irqrestore(&head->vm_lock, flags);
+ return c;
+}
+
+void arm_vmregion_free(struct arm_vmregion_head *head, struct arm_vmregion *c)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&head->vm_lock, flags);
+ list_del(&c->vm_list);
+ spin_unlock_irqrestore(&head->vm_lock, flags);
+
+ kfree(c);
+}