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kernel_optimize_test/arch/arm/mach-ixp4xx/common-pci.c
Kees Cook 6396bb2215 treewide: kzalloc() -> kcalloc() 
The kzalloc() function has a 2-factor argument form, kcalloc(). This
patch replaces cases of:

        kzalloc(a * b, gfp)

with:
        kcalloc(a * b, gfp)

as well as handling cases of:

        kzalloc(a * b * c, gfp)

with:

        kzalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kzalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kzalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kzalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kzalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kzalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kzalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kzalloc
+ kcalloc
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kzalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kzalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kzalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kzalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kzalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kzalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kzalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kzalloc(sizeof(THING) * C2, ...)
|
  kzalloc(sizeof(TYPE) * C2, ...)
|
  kzalloc(C1 * C2 * C3, ...)
|
  kzalloc(C1 * C2, ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kzalloc
+ kcalloc
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00

456 lines
11 KiB
C
Raw Blame History

/*
* arch/arm/mach-ixp4xx/common-pci.c
*
* IXP4XX PCI routines for all platforms
*
* Maintainer: Deepak Saxena <dsaxena@plexity.net>
*
* Copyright (C) 2002 Intel Corporation.
* Copyright (C) 2003 Greg Ungerer <gerg@snapgear.com>
* Copyright (C) 2003-2004 MontaVista Software, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/export.h>
#include <asm/dma-mapping.h>
#include <asm/cputype.h>
#include <asm/irq.h>
#include <asm/sizes.h>
#include <asm/mach/pci.h>
#include <mach/hardware.h>
/*
* IXP4xx PCI read function is dependent on whether we are
* running A0 or B0 (AppleGate) silicon.
*/
int (*ixp4xx_pci_read)(u32 addr, u32 cmd, u32* data);
/*
* Base address for PCI register region
*/
unsigned long ixp4xx_pci_reg_base = 0;
/*
* PCI cfg an I/O routines are done by programming a
* command/byte enable register, and then read/writing
* the data from a data register. We need to ensure
* these transactions are atomic or we will end up
* with corrupt data on the bus or in a driver.
*/
static DEFINE_RAW_SPINLOCK(ixp4xx_pci_lock);
/*
* Read from PCI config space
*/
static void crp_read(u32 ad_cbe, u32 *data)
{
unsigned long flags;
raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
*PCI_CRP_AD_CBE = ad_cbe;
*data = *PCI_CRP_RDATA;
raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
}
/*
* Write to PCI config space
*/
static void crp_write(u32 ad_cbe, u32 data)
{
unsigned long flags;
raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
*PCI_CRP_AD_CBE = CRP_AD_CBE_WRITE | ad_cbe;
*PCI_CRP_WDATA = data;
raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
}
static inline int check_master_abort(void)
{
/* check Master Abort bit after access */
unsigned long isr = *PCI_ISR;
if (isr & PCI_ISR_PFE) {
/* make sure the Master Abort bit is reset */
*PCI_ISR = PCI_ISR_PFE;
pr_debug("%s failed\n", __func__);
return 1;
}
return 0;
}
int ixp4xx_pci_read_errata(u32 addr, u32 cmd, u32* data)
{
unsigned long flags;
int retval = 0;
int i;
raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
*PCI_NP_AD = addr;
/*
* PCI workaround - only works if NP PCI space reads have
* no side effects!!! Read 8 times. last one will be good.
*/
for (i = 0; i < 8; i++) {
*PCI_NP_CBE = cmd;
*data = *PCI_NP_RDATA;
*data = *PCI_NP_RDATA;
}
if(check_master_abort())
retval = 1;
raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
return retval;
}
int ixp4xx_pci_read_no_errata(u32 addr, u32 cmd, u32* data)
{
unsigned long flags;
int retval = 0;
raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
*PCI_NP_AD = addr;
/* set up and execute the read */
*PCI_NP_CBE = cmd;
/* the result of the read is now in NP_RDATA */
*data = *PCI_NP_RDATA;
if(check_master_abort())
retval = 1;
raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
return retval;
}
int ixp4xx_pci_write(u32 addr, u32 cmd, u32 data)
{
unsigned long flags;
int retval = 0;
raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
*PCI_NP_AD = addr;
/* set up the write */
*PCI_NP_CBE = cmd;
/* execute the write by writing to NP_WDATA */
*PCI_NP_WDATA = data;
if(check_master_abort())
retval = 1;
raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
return retval;
}
static u32 ixp4xx_config_addr(u8 bus_num, u16 devfn, int where)
{
u32 addr;
if (!bus_num) {
/* type 0 */
addr = BIT(32-PCI_SLOT(devfn)) | ((PCI_FUNC(devfn)) << 8) |
(where & ~3);
} else {
/* type 1 */
addr = (bus_num << 16) | ((PCI_SLOT(devfn)) << 11) |
((PCI_FUNC(devfn)) << 8) | (where & ~3) | 1;
}
return addr;
}
/*
* Mask table, bits to mask for quantity of size 1, 2 or 4 bytes.
* 0 and 3 are not valid indexes...
*/
static u32 bytemask[] = {
/*0*/ 0,
/*1*/ 0xff,
/*2*/ 0xffff,
/*3*/ 0,
/*4*/ 0xffffffff,
};
static u32 local_byte_lane_enable_bits(u32 n, int size)
{
if (size == 1)
return (0xf & ~BIT(n)) << CRP_AD_CBE_BESL;
if (size == 2)
return (0xf & ~(BIT(n) | BIT(n+1))) << CRP_AD_CBE_BESL;
if (size == 4)
return 0;
return 0xffffffff;
}
static int local_read_config(int where, int size, u32 *value)
{
u32 n, data;
pr_debug("local_read_config from %d size %d\n", where, size);
n = where % 4;
crp_read(where & ~3, &data);
*value = (data >> (8*n)) & bytemask[size];
pr_debug("local_read_config read %#x\n", *value);
return PCIBIOS_SUCCESSFUL;
}
static int local_write_config(int where, int size, u32 value)
{
u32 n, byte_enables, data;
pr_debug("local_write_config %#x to %d size %d\n", value, where, size);
n = where % 4;
byte_enables = local_byte_lane_enable_bits(n, size);
if (byte_enables == 0xffffffff)
return PCIBIOS_BAD_REGISTER_NUMBER;
data = value << (8*n);
crp_write((where & ~3) | byte_enables, data);
return PCIBIOS_SUCCESSFUL;
}
static u32 byte_lane_enable_bits(u32 n, int size)
{
if (size == 1)
return (0xf & ~BIT(n)) << 4;
if (size == 2)
return (0xf & ~(BIT(n) | BIT(n+1))) << 4;
if (size == 4)
return 0;
return 0xffffffff;
}
static int ixp4xx_pci_read_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
{
u32 n, byte_enables, addr, data;
u8 bus_num = bus->number;
pr_debug("read_config from %d size %d dev %d:%d:%d\n", where, size,
bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn));
*value = 0xffffffff;
n = where % 4;
byte_enables = byte_lane_enable_bits(n, size);
if (byte_enables == 0xffffffff)
return PCIBIOS_BAD_REGISTER_NUMBER;
addr = ixp4xx_config_addr(bus_num, devfn, where);
if (ixp4xx_pci_read(addr, byte_enables | NP_CMD_CONFIGREAD, &data))
return PCIBIOS_DEVICE_NOT_FOUND;
*value = (data >> (8*n)) & bytemask[size];
pr_debug("read_config_byte read %#x\n", *value);
return PCIBIOS_SUCCESSFUL;
}
static int ixp4xx_pci_write_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value)
{
u32 n, byte_enables, addr, data;
u8 bus_num = bus->number;
pr_debug("write_config_byte %#x to %d size %d dev %d:%d:%d\n", value, where,
size, bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn));
n = where % 4;
byte_enables = byte_lane_enable_bits(n, size);
if (byte_enables == 0xffffffff)
return PCIBIOS_BAD_REGISTER_NUMBER;
addr = ixp4xx_config_addr(bus_num, devfn, where);
data = value << (8*n);
if (ixp4xx_pci_write(addr, byte_enables | NP_CMD_CONFIGWRITE, data))
return PCIBIOS_DEVICE_NOT_FOUND;
return PCIBIOS_SUCCESSFUL;
}
struct pci_ops ixp4xx_ops = {
.read = ixp4xx_pci_read_config,
.write = ixp4xx_pci_write_config,
};
/*
* PCI abort handler
*/
static int abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
{
u32 isr, status;
isr = *PCI_ISR;
local_read_config(PCI_STATUS, 2, &status);
pr_debug("PCI: abort_handler addr = %#lx, isr = %#x, "
"status = %#x\n", addr, isr, status);
/* make sure the Master Abort bit is reset */
*PCI_ISR = PCI_ISR_PFE;
status |= PCI_STATUS_REC_MASTER_ABORT;
local_write_config(PCI_STATUS, 2, status);
/*
* If it was an imprecise abort, then we need to correct the
* return address to be _after_ the instruction.
*/
if (fsr & (1 << 10))
regs->ARM_pc += 4;
return 0;
}
void __init ixp4xx_pci_preinit(void)
{
unsigned long cpuid = read_cpuid_id();
#ifdef CONFIG_IXP4XX_INDIRECT_PCI
pcibios_min_mem = 0x10000000; /* 1 GB of indirect PCI MMIO space */
#else
pcibios_min_mem = 0x48000000; /* 64 MB of PCI MMIO space */
#endif
/*
* Determine which PCI read method to use.
* Rev 0 IXP425 requires workaround.
*/
if (!(cpuid & 0xf) && cpu_is_ixp42x()) {
printk("PCI: IXP42x A0 silicon detected - "
"PCI Non-Prefetch Workaround Enabled\n");
ixp4xx_pci_read = ixp4xx_pci_read_errata;
} else
ixp4xx_pci_read = ixp4xx_pci_read_no_errata;
/* hook in our fault handler for PCI errors */
hook_fault_code(16+6, abort_handler, SIGBUS, 0,
"imprecise external abort");
pr_debug("setup PCI-AHB(inbound) and AHB-PCI(outbound) address mappings\n");
/*
* We use identity AHB->PCI address translation
* in the 0x48000000 to 0x4bffffff address space
*/
*PCI_PCIMEMBASE = 0x48494A4B;
/*
* We also use identity PCI->AHB address translation
* in 4 16MB BARs that begin at the physical memory start
*/
*PCI_AHBMEMBASE = (PHYS_OFFSET & 0xFF000000) +
((PHYS_OFFSET & 0xFF000000) >> 8) +
((PHYS_OFFSET & 0xFF000000) >> 16) +
((PHYS_OFFSET & 0xFF000000) >> 24) +
0x00010203;
if (*PCI_CSR & PCI_CSR_HOST) {
printk("PCI: IXP4xx is host\n");
pr_debug("setup BARs in controller\n");
/*
* We configure the PCI inbound memory windows to be
* 1:1 mapped to SDRAM
*/
local_write_config(PCI_BASE_ADDRESS_0, 4, PHYS_OFFSET);
local_write_config(PCI_BASE_ADDRESS_1, 4, PHYS_OFFSET + SZ_16M);
local_write_config(PCI_BASE_ADDRESS_2, 4, PHYS_OFFSET + SZ_32M);
local_write_config(PCI_BASE_ADDRESS_3, 4,
PHYS_OFFSET + SZ_32M + SZ_16M);
/*
* Enable CSR window at 64 MiB to allow PCI masters
* to continue prefetching past 64 MiB boundary.
*/
local_write_config(PCI_BASE_ADDRESS_4, 4, PHYS_OFFSET + SZ_64M);
/*
* Enable the IO window to be way up high, at 0xfffffc00
*/
local_write_config(PCI_BASE_ADDRESS_5, 4, 0xfffffc01);
local_write_config(0x40, 4, 0x000080FF); /* No TRDY time limit */
} else {
printk("PCI: IXP4xx is target - No bus scan performed\n");
}
printk("PCI: IXP4xx Using %s access for memory space\n",
#ifndef CONFIG_IXP4XX_INDIRECT_PCI
"direct"
#else
"indirect"
#endif
);
pr_debug("clear error bits in ISR\n");
*PCI_ISR = PCI_ISR_PSE | PCI_ISR_PFE | PCI_ISR_PPE | PCI_ISR_AHBE;
/*
* Set Initialize Complete in PCI Control Register: allow IXP4XX to
* respond to PCI configuration cycles. Specify that the AHB bus is
* operating in big endian mode. Set up byte lane swapping between
* little-endian PCI and the big-endian AHB bus
*/
#ifdef __ARMEB__
*PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE | PCI_CSR_PDS | PCI_CSR_ADS;
#else
*PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE;
#endif
pr_debug("DONE\n");
}
int ixp4xx_setup(int nr, struct pci_sys_data *sys)
{
struct resource *res;
if (nr >= 1)
return 0;
res = kcalloc(2, sizeof(*res), GFP_KERNEL);
if (res == NULL) {
/*
* If we're out of memory this early, something is wrong,
* so we might as well catch it here.
*/
panic("PCI: unable to allocate resources?\n");
}
local_write_config(PCI_COMMAND, 2, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
res[0].name = "PCI I/O Space";
res[0].start = 0x00000000;
res[0].end = 0x0000ffff;
res[0].flags = IORESOURCE_IO;
res[1].name = "PCI Memory Space";
res[1].start = PCIBIOS_MIN_MEM;
res[1].end = PCIBIOS_MAX_MEM;
res[1].flags = IORESOURCE_MEM;
request_resource(&ioport_resource, &res[0]);
request_resource(&iomem_resource, &res[1]);
pci_add_resource_offset(&sys->resources, &res[0], sys->io_offset);
pci_add_resource_offset(&sys->resources, &res[1], sys->mem_offset);
return 1;
}
EXPORT_SYMBOL(ixp4xx_pci_read);
EXPORT_SYMBOL(ixp4xx_pci_write);
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