linux/arch/powerpc/platforms/pseries/eeh_cache.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

310 lines
8.6 KiB
C

/*
* eeh_cache.c
* PCI address cache; allows the lookup of PCI devices based on I/O address
*
* Copyright IBM Corporation 2004
* Copyright Linas Vepstas <linas@austin.ibm.com> 2004
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/list.h>
#include <linux/pci.h>
#include <linux/rbtree.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <asm/atomic.h>
#include <asm/pci-bridge.h>
#include <asm/ppc-pci.h>
/**
* The pci address cache subsystem. This subsystem places
* PCI device address resources into a red-black tree, sorted
* according to the address range, so that given only an i/o
* address, the corresponding PCI device can be **quickly**
* found. It is safe to perform an address lookup in an interrupt
* context; this ability is an important feature.
*
* Currently, the only customer of this code is the EEH subsystem;
* thus, this code has been somewhat tailored to suit EEH better.
* In particular, the cache does *not* hold the addresses of devices
* for which EEH is not enabled.
*
* (Implementation Note: The RB tree seems to be better/faster
* than any hash algo I could think of for this problem, even
* with the penalty of slow pointer chases for d-cache misses).
*/
struct pci_io_addr_range
{
struct rb_node rb_node;
unsigned long addr_lo;
unsigned long addr_hi;
struct pci_dev *pcidev;
unsigned int flags;
};
static struct pci_io_addr_cache
{
struct rb_root rb_root;
spinlock_t piar_lock;
} pci_io_addr_cache_root;
static inline struct pci_dev *__pci_get_device_by_addr(unsigned long addr)
{
struct rb_node *n = pci_io_addr_cache_root.rb_root.rb_node;
while (n) {
struct pci_io_addr_range *piar;
piar = rb_entry(n, struct pci_io_addr_range, rb_node);
if (addr < piar->addr_lo) {
n = n->rb_left;
} else {
if (addr > piar->addr_hi) {
n = n->rb_right;
} else {
pci_dev_get(piar->pcidev);
return piar->pcidev;
}
}
}
return NULL;
}
/**
* pci_get_device_by_addr - Get device, given only address
* @addr: mmio (PIO) phys address or i/o port number
*
* Given an mmio phys address, or a port number, find a pci device
* that implements this address. Be sure to pci_dev_put the device
* when finished. I/O port numbers are assumed to be offset
* from zero (that is, they do *not* have pci_io_addr added in).
* It is safe to call this function within an interrupt.
*/
struct pci_dev *pci_get_device_by_addr(unsigned long addr)
{
struct pci_dev *dev;
unsigned long flags;
spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags);
dev = __pci_get_device_by_addr(addr);
spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags);
return dev;
}
#ifdef DEBUG
/*
* Handy-dandy debug print routine, does nothing more
* than print out the contents of our addr cache.
*/
static void pci_addr_cache_print(struct pci_io_addr_cache *cache)
{
struct rb_node *n;
int cnt = 0;
n = rb_first(&cache->rb_root);
while (n) {
struct pci_io_addr_range *piar;
piar = rb_entry(n, struct pci_io_addr_range, rb_node);
printk(KERN_DEBUG "PCI: %s addr range %d [%lx-%lx]: %s\n",
(piar->flags & IORESOURCE_IO) ? "i/o" : "mem", cnt,
piar->addr_lo, piar->addr_hi, pci_name(piar->pcidev));
cnt++;
n = rb_next(n);
}
}
#endif
/* Insert address range into the rb tree. */
static struct pci_io_addr_range *
pci_addr_cache_insert(struct pci_dev *dev, unsigned long alo,
unsigned long ahi, unsigned int flags)
{
struct rb_node **p = &pci_io_addr_cache_root.rb_root.rb_node;
struct rb_node *parent = NULL;
struct pci_io_addr_range *piar;
/* Walk tree, find a place to insert into tree */
while (*p) {
parent = *p;
piar = rb_entry(parent, struct pci_io_addr_range, rb_node);
if (ahi < piar->addr_lo) {
p = &parent->rb_left;
} else if (alo > piar->addr_hi) {
p = &parent->rb_right;
} else {
if (dev != piar->pcidev ||
alo != piar->addr_lo || ahi != piar->addr_hi) {
printk(KERN_WARNING "PIAR: overlapping address range\n");
}
return piar;
}
}
piar = kmalloc(sizeof(struct pci_io_addr_range), GFP_ATOMIC);
if (!piar)
return NULL;
pci_dev_get(dev);
piar->addr_lo = alo;
piar->addr_hi = ahi;
piar->pcidev = dev;
piar->flags = flags;
#ifdef DEBUG
printk(KERN_DEBUG "PIAR: insert range=[%lx:%lx] dev=%s\n",
alo, ahi, pci_name (dev));
#endif
rb_link_node(&piar->rb_node, parent, p);
rb_insert_color(&piar->rb_node, &pci_io_addr_cache_root.rb_root);
return piar;
}
static void __pci_addr_cache_insert_device(struct pci_dev *dev)
{
struct device_node *dn;
struct pci_dn *pdn;
int i;
dn = pci_device_to_OF_node(dev);
if (!dn) {
printk(KERN_WARNING "PCI: no pci dn found for dev=%s\n", pci_name(dev));
return;
}
/* Skip any devices for which EEH is not enabled. */
pdn = PCI_DN(dn);
if (!(pdn->eeh_mode & EEH_MODE_SUPPORTED) ||
pdn->eeh_mode & EEH_MODE_NOCHECK) {
#ifdef DEBUG
printk(KERN_INFO "PCI: skip building address cache for=%s - %s\n",
pci_name(dev), pdn->node->full_name);
#endif
return;
}
/* Walk resources on this device, poke them into the tree */
for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
unsigned long start = pci_resource_start(dev,i);
unsigned long end = pci_resource_end(dev,i);
unsigned int flags = pci_resource_flags(dev,i);
/* We are interested only bus addresses, not dma or other stuff */
if (0 == (flags & (IORESOURCE_IO | IORESOURCE_MEM)))
continue;
if (start == 0 || ~start == 0 || end == 0 || ~end == 0)
continue;
pci_addr_cache_insert(dev, start, end, flags);
}
}
/**
* pci_addr_cache_insert_device - Add a device to the address cache
* @dev: PCI device whose I/O addresses we are interested in.
*
* In order to support the fast lookup of devices based on addresses,
* we maintain a cache of devices that can be quickly searched.
* This routine adds a device to that cache.
*/
void pci_addr_cache_insert_device(struct pci_dev *dev)
{
unsigned long flags;
/* Ignore PCI bridges */
if ((dev->class >> 16) == PCI_BASE_CLASS_BRIDGE)
return;
spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags);
__pci_addr_cache_insert_device(dev);
spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags);
}
static inline void __pci_addr_cache_remove_device(struct pci_dev *dev)
{
struct rb_node *n;
restart:
n = rb_first(&pci_io_addr_cache_root.rb_root);
while (n) {
struct pci_io_addr_range *piar;
piar = rb_entry(n, struct pci_io_addr_range, rb_node);
if (piar->pcidev == dev) {
rb_erase(n, &pci_io_addr_cache_root.rb_root);
pci_dev_put(piar->pcidev);
kfree(piar);
goto restart;
}
n = rb_next(n);
}
}
/**
* pci_addr_cache_remove_device - remove pci device from addr cache
* @dev: device to remove
*
* Remove a device from the addr-cache tree.
* This is potentially expensive, since it will walk
* the tree multiple times (once per resource).
* But so what; device removal doesn't need to be that fast.
*/
void pci_addr_cache_remove_device(struct pci_dev *dev)
{
unsigned long flags;
spin_lock_irqsave(&pci_io_addr_cache_root.piar_lock, flags);
__pci_addr_cache_remove_device(dev);
spin_unlock_irqrestore(&pci_io_addr_cache_root.piar_lock, flags);
}
/**
* pci_addr_cache_build - Build a cache of I/O addresses
*
* Build a cache of pci i/o addresses. This cache will be used to
* find the pci device that corresponds to a given address.
* This routine scans all pci busses to build the cache.
* Must be run late in boot process, after the pci controllers
* have been scanned for devices (after all device resources are known).
*/
void __init pci_addr_cache_build(void)
{
struct device_node *dn;
struct pci_dev *dev = NULL;
spin_lock_init(&pci_io_addr_cache_root.piar_lock);
while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
pci_addr_cache_insert_device(dev);
dn = pci_device_to_OF_node(dev);
if (!dn)
continue;
pci_dev_get(dev); /* matching put is in eeh_remove_device() */
PCI_DN(dn)->pcidev = dev;
eeh_sysfs_add_device(dev);
}
#ifdef DEBUG
/* Verify tree built up above, echo back the list of addrs. */
pci_addr_cache_print(&pci_io_addr_cache_root);
#endif
}