Revision 7ce9d5d1f3c8736511daa413c64985a05b2feee3 authored by Eric Sandeen on 04 March 2009, 23:38:18 UTC, committed by Theodore Ts'o on 04 March 2009, 23:38:18 UTC
I was seeing fsck errors on inode bitmaps after a 4 thread dbench run on a 4 cpu machine: Inode bitmap differences: -50736 -(50752--50753) etc... I believe that this is because ext4_free_inode() uses atomic bitops, and although ext4_new_inode() *used* to also use atomic bitops for synchronization, commit 393418676a7602e1d7d3f6e560159c65c8cbd50e changed this to use the sb_bgl_lock, so that we could also synchronize against read_inode_bitmap and initialization of uninit inode tables. However, that change left ext4_free_inode using atomic bitops, which I think leaves no synchronization between setting & unsetting bits in the inode table. The below patch fixes it for me, although I wonder if we're getting at all heavy-handed with this spinlock... Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
1 parent fec6c6f
mca-device.c
/* -*- mode: c; c-basic-offset: 8 -*- */
/*
* MCA device support functions
*
* These functions support the ongoing device access API.
*
* (C) 2002 James Bottomley <James.Bottomley@HansenPartnership.com>
*
**-----------------------------------------------------------------------------
**
** 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., 675 Mass Ave, Cambridge, MA 02139, USA.
**
**-----------------------------------------------------------------------------
*/
#include <linux/module.h>
#include <linux/device.h>
#include <linux/mca.h>
#include <linux/string.h>
/**
* mca_device_read_stored_pos - read POS register from stored data
* @mca_dev: device to read from
* @reg: register to read from
*
* Fetch a POS value that was stored at boot time by the kernel
* when it scanned the MCA space. The register value is returned.
* Missing or invalid registers report 0.
*/
unsigned char mca_device_read_stored_pos(struct mca_device *mca_dev, int reg)
{
if(reg < 0 || reg >= 8)
return 0;
return mca_dev->pos[reg];
}
EXPORT_SYMBOL(mca_device_read_stored_pos);
/**
* mca_device_read_pos - read POS register from card
* @mca_dev: device to read from
* @reg: register to read from
*
* Fetch a POS value directly from the hardware to obtain the
* current value. This is much slower than
* mca_device_read_stored_pos and may not be invoked from
* interrupt context. It handles the deep magic required for
* onboard devices transparently.
*/
unsigned char mca_device_read_pos(struct mca_device *mca_dev, int reg)
{
struct mca_bus *mca_bus = to_mca_bus(mca_dev->dev.parent);
return mca_bus->f.mca_read_pos(mca_dev, reg);
return mca_dev->pos[reg];
}
EXPORT_SYMBOL(mca_device_read_pos);
/**
* mca_device_write_pos - read POS register from card
* @mca_dev: device to write pos register to
* @reg: register to write to
* @byte: byte to write to the POS registers
*
* Store a POS value directly to the hardware. You should not
* normally need to use this function and should have a very good
* knowledge of MCA bus before you do so. Doing this wrongly can
* damage the hardware.
*
* This function may not be used from interrupt context.
*
*/
void mca_device_write_pos(struct mca_device *mca_dev, int reg,
unsigned char byte)
{
struct mca_bus *mca_bus = to_mca_bus(mca_dev->dev.parent);
mca_bus->f.mca_write_pos(mca_dev, reg, byte);
}
EXPORT_SYMBOL(mca_device_write_pos);
/**
* mca_device_transform_irq - transform the ADF obtained IRQ
* @mca_device: device whose irq needs transforming
* @irq: input irq from ADF
*
* MCA Adapter Definition Files (ADF) contain irq, ioport, memory
* etc. definitions. In systems with more than one bus, these need
* to be transformed through bus mapping functions to get the real
* system global quantities.
*
* This function transforms the interrupt number and returns the
* transformed system global interrupt
*/
int mca_device_transform_irq(struct mca_device *mca_dev, int irq)
{
struct mca_bus *mca_bus = to_mca_bus(mca_dev->dev.parent);
return mca_bus->f.mca_transform_irq(mca_dev, irq);
}
EXPORT_SYMBOL(mca_device_transform_irq);
/**
* mca_device_transform_ioport - transform the ADF obtained I/O port
* @mca_device: device whose port needs transforming
* @ioport: input I/O port from ADF
*
* MCA Adapter Definition Files (ADF) contain irq, ioport, memory
* etc. definitions. In systems with more than one bus, these need
* to be transformed through bus mapping functions to get the real
* system global quantities.
*
* This function transforms the I/O port number and returns the
* transformed system global port number.
*
* This transformation can be assumed to be linear for port ranges.
*/
int mca_device_transform_ioport(struct mca_device *mca_dev, int port)
{
struct mca_bus *mca_bus = to_mca_bus(mca_dev->dev.parent);
return mca_bus->f.mca_transform_ioport(mca_dev, port);
}
EXPORT_SYMBOL(mca_device_transform_ioport);
/**
* mca_device_transform_memory - transform the ADF obtained memory
* @mca_device: device whose memory region needs transforming
* @mem: memory region start from ADF
*
* MCA Adapter Definition Files (ADF) contain irq, ioport, memory
* etc. definitions. In systems with more than one bus, these need
* to be transformed through bus mapping functions to get the real
* system global quantities.
*
* This function transforms the memory region start and returns the
* transformed system global memory region (physical).
*
* This transformation can be assumed to be linear for region ranges.
*/
void *mca_device_transform_memory(struct mca_device *mca_dev, void *mem)
{
struct mca_bus *mca_bus = to_mca_bus(mca_dev->dev.parent);
return mca_bus->f.mca_transform_memory(mca_dev, mem);
}
EXPORT_SYMBOL(mca_device_transform_memory);
/**
* mca_device_claimed - check if claimed by driver
* @mca_dev: device to check
*
* Returns 1 if the slot has been claimed by a driver
*/
int mca_device_claimed(struct mca_device *mca_dev)
{
return mca_dev->driver_loaded;
}
EXPORT_SYMBOL(mca_device_claimed);
/**
* mca_device_set_claim - set the claim value of the driver
* @mca_dev: device to set value for
* @val: claim value to set (1 claimed, 0 unclaimed)
*/
void mca_device_set_claim(struct mca_device *mca_dev, int val)
{
mca_dev->driver_loaded = val;
}
EXPORT_SYMBOL(mca_device_set_claim);
/**
* mca_device_status - get the status of the device
* @mca_device: device to get
*
* returns an enumeration of the device status:
*
* MCA_ADAPTER_NORMAL adapter is OK.
* MCA_ADAPTER_NONE no adapter at device (should never happen).
* MCA_ADAPTER_DISABLED adapter is disabled.
* MCA_ADAPTER_ERROR adapter cannot be initialised.
*/
enum MCA_AdapterStatus mca_device_status(struct mca_device *mca_dev)
{
return mca_dev->status;
}
EXPORT_SYMBOL(mca_device_status);
/**
* mca_device_set_name - set the name of the device
* @mca_device: device to set the name of
* @name: name to set
*/
void mca_device_set_name(struct mca_device *mca_dev, const char *name)
{
if(!mca_dev)
return;
strlcpy(mca_dev->name, name, sizeof(mca_dev->name));
}
EXPORT_SYMBOL(mca_device_set_name);
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