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Message-Id: <1455700391-11702-1-git-send-email-kuleshovmail@gmail.com>
Date: Wed, 17 Feb 2016 15:13:11 +0600
From: Alexander Kuleshov <kuleshovmail@...il.com>
To: Ingo Molnar <mingo@...hat.com>
Cc: Thomas Gleixner <tglx@...utronix.de>,
"H . Peter Anvin" <hpa@...or.com>, x86@...nel.org,
Borislav Petkov <bp@...e.de>, Joerg Roedel <jroedel@...e.de>,
Dave Young <dyoung@...hat.com>,
Andrew Morton <akpm@...ux-foundation.org>,
Jiri Kosina <jkosina@...e.cz>, Baoquan He <bhe@...hat.com>,
Mark Salter <msalter@...hat.com>, linux-kernel@...r.kernel.org,
Alexander Kuleshov <kuleshovmail@...il.com>
Subject: [PATCH v5] x86/setup: get ramdisk parameters only once
The check and definitions related to ramdisk are similar in the
early_reserve_initrd() and reserve_initrd() functions.
This patch introduces struct ramdisk which contains information
about initrd. This structure will be filled in the setup_arch()
and passed to the reserve_initrd() and relocate_initrd() functions.
This allows us to not get/check ramdisk parameters from the bootparams
every time in the early_reserve_initrd(), reserve_initrd() and
relocate_initrd() function.
Additionally we save 85 bytes:
text data bss dec hex filename
9292517 5011696 15675392 29979605 1c973d5 vmlinux
text data bss dec hex filename
9292602 5011696 15675392 29979690 1c9742a vmlinux
Signed-off-by: Alexander Kuleshov <kuleshovmail@...il.com>
---
Tested as with virtual machine as with real hardware.
Changelog:
v5:
* move check of the reserve_ramdisk to the reserve_initrd()
* align ramdisk size in setup_arch() as it maybe not page
aligned and start_addr + size() will be different with end_addr
in this case
* style fixes
v4:
* bool reserve_ramdisk moved to the struct ramdisk;
* fields of struct ramdisk are renamed to more understandable
names
* early_reserve_initrd() removed as it contains only one call
of memblock_resere. It was moved to the setup_arch
* stubs added for get_ramdisk_image() and get_ramdisk_size()
to prevent compilation error if CONFIG_BLK_DEV_INITRD=n
* initialization of ramdisk->end_addr is moved from in-place
initialization to prevent ‘ramdisk_image.size’ is used uninitialized
in this function warning.
v3: introduced ramdisk setup which is filled in th
setup_arch() and passed to the early_reserve_initrd()
and reserve_initrd().
v2: parameter of reserve_initrd() - int -> bool.
commit message updated.
arch/x86/kernel/setup.c | 103 +++++++++++++++++++++++++-----------------------
1 file changed, 53 insertions(+), 50 deletions(-)
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index d3d80e6..d89d9ea 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -169,6 +169,15 @@ static struct resource bss_resource = {
.flags = IORESOURCE_BUSY | IORESOURCE_MEM
};
+/*
+ * ramdisk setup
+ */
+struct ramdisk {
+ u64 start_addr; /* ramdisk load address */
+ u64 end_addr; /* ramdisk end address */
+ u64 size; /* ramdisk size */
+ bool reserve_ramdisk; /* do initrd provided by bootloader */
+};
#ifdef CONFIG_X86_32
/* cpu data as detected by the assembly code in head.S */
@@ -318,90 +327,73 @@ static u64 __init get_ramdisk_size(void)
return ramdisk_size;
}
-static void __init relocate_initrd(void)
+static void __init relocate_initrd(struct ramdisk *ramdisk)
{
- /* Assume only end is not page aligned */
- u64 ramdisk_image = get_ramdisk_image();
- u64 ramdisk_size = get_ramdisk_size();
- u64 area_size = PAGE_ALIGN(ramdisk_size);
-
/* We need to move the initrd down into directly mapped mem */
relocated_ramdisk = memblock_find_in_range(0, PFN_PHYS(max_pfn_mapped),
- area_size, PAGE_SIZE);
+ ramdisk->size, PAGE_SIZE);
if (!relocated_ramdisk)
panic("Cannot find place for new RAMDISK of size %lld\n",
- ramdisk_size);
+ ramdisk->size);
/* Note: this includes all the mem currently occupied by
the initrd, we rely on that fact to keep the data intact. */
- memblock_reserve(relocated_ramdisk, area_size);
+ memblock_reserve(relocated_ramdisk, ramdisk->size);
initrd_start = relocated_ramdisk + PAGE_OFFSET;
- initrd_end = initrd_start + ramdisk_size;
+ initrd_end = initrd_start + ramdisk->size;
printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
- relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
+ relocated_ramdisk, relocated_ramdisk + ramdisk->size - 1);
- copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size);
+ copy_from_early_mem((void *)initrd_start, ramdisk->start_addr, ramdisk->size);
printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
" [mem %#010llx-%#010llx]\n",
- ramdisk_image, ramdisk_image + ramdisk_size - 1,
- relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
+ ramdisk->start_addr, ramdisk->start_addr + ramdisk->size - 1,
+ relocated_ramdisk, relocated_ramdisk + ramdisk->size - 1);
}
-static void __init early_reserve_initrd(void)
-{
- /* Assume only end is not page aligned */
- u64 ramdisk_image = get_ramdisk_image();
- u64 ramdisk_size = get_ramdisk_size();
- u64 ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size);
-
- if (!boot_params.hdr.type_of_loader ||
- !ramdisk_image || !ramdisk_size)
- return; /* No initrd provided by bootloader */
-
- memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
-}
-static void __init reserve_initrd(void)
+static void __init reserve_initrd(struct ramdisk *ramdisk)
{
- /* Assume only end is not page aligned */
- u64 ramdisk_image = get_ramdisk_image();
- u64 ramdisk_size = get_ramdisk_size();
- u64 ramdisk_end = PAGE_ALIGN(ramdisk_image + ramdisk_size);
u64 mapped_size;
- if (!boot_params.hdr.type_of_loader ||
- !ramdisk_image || !ramdisk_size)
- return; /* No initrd provided by bootloader */
+ if (!ramdisk->reserve_ramdisk)
+ return;
initrd_start = 0;
mapped_size = memblock_mem_size(max_pfn_mapped);
- if (ramdisk_size >= (mapped_size>>1))
+ if (ramdisk->size >= (mapped_size>>1))
panic("initrd too large to handle, "
"disabling initrd (%lld needed, %lld available)\n",
- ramdisk_size, mapped_size>>1);
+ ramdisk->size, mapped_size>>1);
- printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
- ramdisk_end - 1);
+ printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n",
+ ramdisk->start_addr, ramdisk->end_addr - 1);
- if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
- PFN_DOWN(ramdisk_end))) {
+ if (pfn_range_is_mapped(PFN_DOWN(ramdisk->start_addr),
+ PFN_DOWN(ramdisk->end_addr))) {
/* All are mapped, easy case */
- initrd_start = ramdisk_image + PAGE_OFFSET;
- initrd_end = initrd_start + ramdisk_size;
+ initrd_start = ramdisk->start_addr + PAGE_OFFSET;
+ initrd_end = initrd_start + ramdisk->size;
return;
}
- relocate_initrd();
+ relocate_initrd(ramdisk);
- memblock_free(ramdisk_image, ramdisk_end - ramdisk_image);
+ memblock_free(ramdisk->start_addr,
+ ramdisk->end_addr - ramdisk->start_addr);
}
#else
-static void __init early_reserve_initrd(void)
+static u64 __init get_ramdisk_image(void)
{
+ return 0;
+}
+static u64 __init get_ramdisk_size(void)
+{
+ return 0;
}
-static void __init reserve_initrd(void)
+static void __init reserve_initrd(struct ramdisk *ramdisk)
{
}
#endif /* CONFIG_BLK_DEV_INITRD */
@@ -844,13 +836,24 @@ dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
*
* Note: On x86_64, fixmaps are ready for use even before this is called.
*/
-
void __init setup_arch(char **cmdline_p)
{
+ struct ramdisk ramdisk_image = {
+ .start_addr = get_ramdisk_image(),
+ .size = PAGE_ALIGN(get_ramdisk_size()),
+ .reserve_ramdisk = true
+ };
+
+ /* Assume end is not page aligned */
+ ramdisk_image.end_addr = PAGE_ALIGN(ramdisk_image.start_addr + ramdisk_image.size);
+
memblock_reserve(__pa_symbol(_text),
(unsigned long)__bss_stop - (unsigned long)_text);
- early_reserve_initrd();
+ if (!boot_params.hdr.type_of_loader || !ramdisk_image.start_addr || !ramdisk_image.size)
+ ramdisk_image.reserve_ramdisk = false; /* No initrd provided by bootloader */
+ else
+ memblock_reserve(ramdisk_image.start_addr, ramdisk_image.size);
/*
* At this point everything still needed from the boot loader
@@ -1135,7 +1138,7 @@ void __init setup_arch(char **cmdline_p)
/* Allocate bigger log buffer */
setup_log_buf(1);
- reserve_initrd();
+ reserve_initrd(&ramdisk_image);
#if defined(CONFIG_ACPI) && defined(CONFIG_BLK_DEV_INITRD)
acpi_initrd_override((void *)initrd_start, initrd_end - initrd_start);
--
2.7.0.364.g4943984
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