This file was using the module get/put functions in two simple inline
functions. But module_get/put were only within scope because of
the implicit presence of module.h being everywhere.
Rather than add module.h to another file in include/ -- which is
exactly the thing we are trying to avoid, simply convert these
one-line functions into a define, as per what was done for the
device_schedule_callback() in commit 523ded71de.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The implicit presence of module.h everywhere meant that this header
also was getting moduleparam.h which defines struct kernel_param.
Since it only needs to know that kernel_param is a struct, call that
out instead of adding an include of moduleparam.h -- to get rid of this:
include/net/netfilter/nf_conntrack.h:316: warning: 'struct kernel_param' declared inside parameter list
include/net/netfilter/nf_conntrack.h:316: warning: its scope is only this definition or declaration, which is probably not what you want
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The <linux/module.h> pretty much brings in the kitchen sink along
with it, so it should be avoided wherever reasonably possible in
terms of being included from other commonly used <linux/something.h>
files, as it results in a measureable increase on compile times.
The worst culprit was probably device.h since it is used everywhere.
This file also had an implicit dependency/usage of mutex.h which was
masked by module.h, and is also fixed here at the same time.
There are over a dozen other headers that simply declare the
struct instead of pulling in the whole file, so follow their lead
and simply make it a few more.
Most of the implicit dependencies on module.h being present by
these headers pulling it in have been now weeded out, so we can
finally make this change with hopefully minimal breakage.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The original implementations reference THIS_MODULE in an inline.
We could include <linux/export.h>, but it is better to avoid chaining.
Fortunately someone else already thought of this, and made a similar
inline into a #define in <linux/device.h> for device_schedule_callback(),
[see commit 523ded71de] so follow that precedent here.
Also bubble up any __must_check that were used on the prev. wrapper inline
functions up one to the real __register functions, to preserve any prev.
sanity checks that were used in those instances.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The <linux/crypto.h> (which is in turn in common headers
like tcp.h) wants to use module_name() in an inline fcn.
But having all of <linux/module.h> along for the ride is
overkill and slows down compiles by a measureable amount,
since it in turn includes lots of headers.
Since the inline is never used anywhere in the kernel[1],
we can just remove it, and then also remove the module.h
include as well.
In all the many crypto modules, there were some relying on
crypto.h including module.h -- for them we now explicitly
call out module.h for inclusion.
[1] git grep shows some staging drivers also define the same
static inline, but they also never ever use it.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Once we clean up the implicit presence of module.h (and all its
sub-includes), we'll see an implicit dependency on page.h for
the PAGE_SIZE define. So fix it in advance.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This file was getting notifier.h via device.h --> module.h but
the module.h inclusion is going away, so add notifier.h directly.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The implicit presence of module.h and all its sub-includes was
masking these implicit header usages:
include/linux/dmaengine.h:684: warning: 'struct page' declared inside parameter list
include/linux/dmaengine.h:684: warning: its scope is only this definition or declaration, which is probably not what you want
include/linux/dmaengine.h:687: warning: 'struct page' declared inside parameter list
include/linux/dmaengine.h:736:2: error: implicit declaration of function 'bitmap_zero'
With input from Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
By removing the implicit presence of module.h from this file, we
will see things like:
In file included from fs/dlm/user.c:9:
include/linux/miscdevice.h:50: error: field ‘list’ has incomplete type
include/linux/miscdevice.h:54: error: expected specifier-qualifier-list before ‘mode_t’
Call out lists.h and types.h for inclusion to fix each of the
above respectively.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This will show up on MIPS when we fix all the implicit header presences
that are because of module.h being everywhere.
In file included from kernel/trace/ftrace.c:16:
include/linux/stop_machine.h: In function 'stop_one_cpu':
include/linux/stop_machine.h:50: error: implicit declaration of function 'smp_processor_id'
include/linux/stop_machine.h: In function 'stop_cpus':
include/linux/stop_machine.h:80: error: implicit declaration of function 'raw_smp_processor_id'
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
It shows up as a build failure on MIPS, as it is used in
three of_property function stubs.
include/linux/of.h:275: error: 'ENOSYS' undeclared (first use in this function)
include/linux/of.h:282: error: 'ENOSYS' undeclared (first use in this function)
include/linux/of.h:295: error: 'ENOSYS' undeclared (first use in this function)
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
There is nothing modular in this file, and no reason to drag
in all the 357 headers that module.h brings with it, since
it just slows down compiles.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This file had an include of module.h which was probably added
in relation to this line:
#define ACPI_EXPORT_SYMBOL(symbol) EXPORT_SYMBOL(symbol);
However, we really expect symbol exporters to grab export.h
themselves, and since this is only a define, we can remove
the module.h include without aclinux.h itself causing any
compile issues.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This file has a define MODULE_ALIAS_MISCDEV which in turn will
use the MODULE_ALIAS define, but only if the former is explicitly
used by modular device driver code (and such code should be
already including module.h).
Delete the include, since module.h is such a giant thing that we
don't want it implicitly sneaking into compiles where it isn't
specifically required.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
There is nothing modular in this file, and no reason to drag
in all the extra headers that module.h brings with it, since
it just slows down compiles.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This file has modular references, but they are limited to
those which are covered by the simple "struct module;"
declaration used in dozens of other places. In fact that
declaration is already there (just outside of the context
of this commit) so simply remove the include line.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
There is nothing module specific in this header, and removing
it doesn't seem to uncover any implicit dependencies either.
Must be simply a vestige of an ancient legacy.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The <linux/module.h> pretty much brings in the kitchen sink along
with it, so it should be avoided wherever reasonably possible in
terms of being included from other commonly used <linux/something.h>
files, as it results in a measureable increase on compile times.
There doesn't appear to be any module specifics in this file.
The obvious people who were relying on the presence of
the vast amount of stuff module.h sucked in have been fixed.
If other files are implicitly relying on it, then lets see who
they are and fix them too.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This file consists of nothing other than things like:
#ifdef CONFIG_FOO
#define ....
There is no reason for it to require module.h
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
This was implicitly appearing by way of module.h -- but when
we fix that, we'll get this:
In file included from drivers/regulator/dummy.c:21:
include/linux/regulator/driver.h:197: error: field 'notifier' has incomplete type
make[3]: *** [drivers/regulator/dummy.o] Error 1
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Things like THIS_MODULE and EXPORT_SYMBOL were simply everywhere
because module.h was also everywhere. But we are fixing the latter.
So we need to call out the real users in advance.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
There are files which use module_param and MODULE_PARM_DESC
back to back. They only include moduleparam.h which makes sense,
but the implicit presence of module.h everywhere hid the fact
that MODULE_PARM_DESC wasn't in moduleparam.h at all. Relocate
the macro to moduleparam.h so that the moduleparam infrastructure
can be used independently of module.h
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
A lot of files pull in module.h when all they are really
looking for is the basic EXPORT_SYMBOL functionality. The
recent data from Ingo[1] shows that this is one of several
instances that has a significant impact on compile times,
and it should be targeted for factoring out (as done here).
Note that several commonly used header files in include/*
directly include <linux/module.h> themselves (some 34 of them!)
The most commonly used ones of these will have to be made
independent of module.h before the full benefit of this change
can be realized.
We also transition THIS_MODULE from module.h to export.h,
since there are lots of files with subsystem structs that
in turn will have a struct module *owner and only be doing:
.owner = THIS_MODULE;
and absolutely nothing else modular. So, we also want to have
the THIS_MODULE definition present in the lightweight header.
[1] https://lkml.org/lkml/2011/5/23/76
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
i2c: Functions for byte-swapped smbus_write/read_word_data
i2c-algo-pca: Return standard fault codes
i2c-algo-bit: Return standard fault codes
i2c-algo-bit: Be verbose on bus testing failure
i2c-algo-bit: Let user test buses without failing
i2c/scx200_acb: Fix section mismatch warning in scx200_pci_drv
i2c: I2C_ELEKTOR should depend on HAS_IOPORT
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (33 commits)
iommu/core: Remove global iommu_ops and register_iommu
iommu/msm: Use bus_set_iommu instead of register_iommu
iommu/omap: Use bus_set_iommu instead of register_iommu
iommu/vt-d: Use bus_set_iommu instead of register_iommu
iommu/amd: Use bus_set_iommu instead of register_iommu
iommu/core: Use bus->iommu_ops in the iommu-api
iommu/core: Convert iommu_found to iommu_present
iommu/core: Add bus_type parameter to iommu_domain_alloc
Driver core: Add iommu_ops to bus_type
iommu/core: Define iommu_ops and register_iommu only with CONFIG_IOMMU_API
iommu/amd: Fix wrong shift direction
iommu/omap: always provide iommu debug code
iommu/core: let drivers know if an iommu fault handler isn't installed
iommu/core: export iommu_set_fault_handler()
iommu/omap: Fix build error with !IOMMU_SUPPORT
iommu/omap: Migrate to the generic fault report mechanism
iommu/core: Add fault reporting mechanism
iommu/core: Use PAGE_SIZE instead of hard-coded value
iommu/core: use the existing IS_ALIGNED macro
iommu/msm: ->unmap() should return order of unmapped page
...
Fixup trivial conflicts in drivers/iommu/Makefile: "move omap iommu to
dedicated iommu folder" vs "Rename the DMAR and INTR_REMAP config
options" just happened to touch lines next to each other.
* 'kvm-updates/3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: (75 commits)
KVM: SVM: Keep intercepting task switching with NPT enabled
KVM: s390: implement sigp external call
KVM: s390: fix register setting
KVM: s390: fix return value of kvm_arch_init_vm
KVM: s390: check cpu_id prior to using it
KVM: emulate lapic tsc deadline timer for guest
x86: TSC deadline definitions
KVM: Fix simultaneous NMIs
KVM: x86 emulator: convert push %sreg/pop %sreg to direct decode
KVM: x86 emulator: switch lds/les/lss/lfs/lgs to direct decode
KVM: x86 emulator: streamline decode of segment registers
KVM: x86 emulator: simplify OpMem64 decode
KVM: x86 emulator: switch src decode to decode_operand()
KVM: x86 emulator: qualify OpReg inhibit_byte_regs hack
KVM: x86 emulator: switch OpImmUByte decode to decode_imm()
KVM: x86 emulator: free up some flag bits near src, dst
KVM: x86 emulator: switch src2 to generic decode_operand()
KVM: x86 emulator: expand decode flags to 64 bits
KVM: x86 emulator: split dst decode to a generic decode_operand()
KVM: x86 emulator: move memop, memopp into emulation context
...
* 'fbdev-next' of git://github.com/schandinat/linux-2.6: (270 commits)
video: platinumfb: Add __devexit_p at necessary place
drivers/video: fsl-diu-fb: merge diu_pool into fsl_diu_data
drivers/video: fsl-diu-fb: merge diu_hw into fsl_diu_data
drivers/video: fsl-diu-fb: only DIU modes 0 and 1 are supported
drivers/video: fsl-diu-fb: remove unused panel operating mode support
drivers/video: fsl-diu-fb: use an enum for the AOI index
drivers/video: fsl-diu-fb: add several new video modes
drivers/video: fsl-diu-fb: remove broken screen blanking support
drivers/video: fsl-diu-fb: move some definitions out of the header file
drivers/video: fsl-diu-fb: fix some ioctls
video: da8xx-fb: Increased resolution configuration of revised LCDC IP
OMAPDSS: picodlp: add missing #include <linux/module.h>
fb: fix au1100fb bitrot.
mx3fb: fix NULL pointer dereference in screen blanking.
video: irq: Remove IRQF_DISABLED
smscufx: change edid data to u8 instead of char
OMAPDSS: DISPC: zorder support for DSS overlays
OMAPDSS: DISPC: VIDEO3 pipeline support
OMAPDSS/OMAP_VOUT: Fix incorrect OMAP3-alpha compatibility setting
video/omap: fix build dependencies
...
Fix up conflicts in:
- drivers/staging/xgifb/XGI_main_26.c
Changes to XGIfb_pan_var()
- drivers/video/omap/{lcd_apollon.c,lcd_ldp.c,lcd_overo.c}
Removed (or in the case of apollon.c, merged into the generic
DSS panel in drivers/video/omap2/displays/panel-generic-dpi.c)
Reimplemented at least 17 times discounting error mangling cases
where it could be used.
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Implement sigp external call, which might be required for guests that
issue an external call instead of an emergency signal for IPI.
This fixes an issue with "KVM: unknown SIGP: 0x02" when booting
such an SMP guest.
Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* 'devicetree/merge' of git://git.secretlab.ca/git/linux-2.6:
ARM: mark empty gpio.h files empty
gpio: Fix ARM versatile-express build failure
of: include errno.h
* 'spi/next' of git://git.secretlab.ca/git/linux-2.6:
drivercore: Add helper macro for platform_driver boilerplate
spi: irq: Remove IRQF_DISABLED
OMAP: SPI: Fix the trying to free nonexistent resource error
spi/spi-ep93xx: add module.h include
spi/tegra: fix compilation error in spi-tegra.c
spi: spi-dw: fix all sparse warnings
spi/spi-pl022: Call pl022_dma_remove(pl022) only if enable_dma is true
spi/spi-pl022: calculate_effective_freq() must set rate <= requested rate
spi/spi-pl022: Don't allocate more sg than required.
spi/spi-pl022: Use GFP_ATOMIC for allocation from tasklet
spi/spi-pl022: Resolve formatting issues
* 'gpio/next' of git://git.secretlab.ca/git/linux-2.6:
h8300: Move gpio.h to gpio-internal.h
gpio: pl061: add DT binding support
gpio: fix build error in include/asm-generic/gpio.h
gpiolib: Ensure struct gpio is always defined
irq: Add EXPORT_SYMBOL_GPL to function of irq generic-chip
gpio-ml-ioh: Use NUMA_NO_NODE not GFP_KERNEL
gpio-pch: Use NUMA_NO_NODE not GFP_KERNEL
gpio: langwell: ensure alternate function is cleared
gpio-pch: Support interrupt function
gpio-pch: Save register value in suspend()
gpio-pch: modify gpio_nums and mask
gpio-pch: support ML7223 IOH n-Bus
gpio-pch: add spinlock in suspend/resume processing
gpio-pch: Delete invalid "restore" code in suspend()
gpio-ml-ioh: Fix suspend/resume issue
gpio-ml-ioh: Support interrupt function
gpio-ml-ioh: Delete unnecessary code
gpio/mxc: add chained_irq_enter/exit() to mx3_gpio_irq_handler()
gpio/nomadik: use genirq core to track enablement
gpio/nomadik: disable clocks when unused
When compiling ath6kl for beagleboard (omap2plus_defconfig plus
CONFIG_ATH6KL, CONFIG_OF disable) with current linux-next compilation
fails:
include/linux/of.h:269: error: 'ENOSYS' undeclared (first use in this function)
include/linux/of.h:276: error: 'ENOSYS' undeclared (first use in this function)
include/linux/of.h:289: error: 'ENOSYS' undeclared (first use in this function)
Fix this by including errno.h from of.h.
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
* 'for-linus' of git://ceph.newdream.net/git/ceph-client:
libceph: fix double-free of page vector
ceph: fix 32-bit ino numbers
libceph: force resend of osd requests if we skip an osdmap
ceph: use kernel DNS resolver
ceph: fix ceph_monc_init memory leak
ceph: let the set_layout ioctl set single traits
Revert "ceph: don't truncate dirty pages in invalidate work thread"
ceph: replace leading spaces with tabs
libceph: warn on msg allocation failures
libceph: don't complain on msgpool alloc failures
libceph: always preallocate mon connection
libceph: create messenger with client
ceph: document ioctls
ceph: implement (optional) max read size
ceph: rename rsize -> rasize
ceph: make readpages fully async
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (549 commits)
ALSA: hda - Fix ADC input-amp handling for Cx20549 codec
ALSA: hda - Keep EAPD turned on for old Conexant chips
ALSA: hda/realtek - Fix missing volume controls with ALC260
ASoC: wm8940: Properly set codec->dapm.bias_level
ALSA: hda - Fix pin-config for ASUS W90V
ALSA: hda - Fix surround/CLFE headphone and speaker pins order
ALSA: hda - Fix typo
ALSA: Update the sound git tree URL
ALSA: HDA: Add new revision for ALC662
ASoC: max98095: Convert codec->hw_write to snd_soc_write
ASoC: keep pointer to resource so it can be freed
ASoC: sgtl5000: Fix wrong mask in some snd_soc_update_bits calls
ASoC: wm8996: Fix wrong mask for setting WM8996_AIF_CLOCKING_2
ASoC: da7210: Add support for line out and DAC
ASoC: da7210: Add support for DAPM
ALSA: hda/realtek - Fix DAC assignments of multiple speakers
ASoC: Use SGTL5000_LINREG_VDDD_MASK instead of hardcoded mask value
ASoC: Set sgtl5000->ldo in ldo_regulator_register
ASoC: wm8996: Use SND_SOC_DAPM_AIF_OUT for AIF2 Capture
ASoC: wm8994: Use SND_SOC_DAPM_AIF_OUT for AIF3 Capture
...
* 'next-rebase' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci:
PCI: Clean-up MPS debug output
pci: Clamp pcie_set_readrq() when using "performance" settings
PCI: enable MPS "performance" setting to properly handle bridge MPS
PCI: Workaround for Intel MPS errata
PCI: Add support for PASID capability
PCI: Add implementation for PRI capability
PCI: Export ATS functions to modules
PCI: Move ATS implementation into own file
PCI / PM: Remove unnecessary error variable from acpi_dev_run_wake()
PCI hotplug: acpiphp: Prevent deadlock on PCI-to-PCI bridge remove
PCI / PM: Extend PME polling to all PCI devices
PCI quirk: mmc: Always check for lower base frequency quirk for Ricoh 1180:e823
PCI: Make pci_setup_bridge() non-static for use by arch code
x86: constify PCI raw ops structures
PCI: Add quirk for known incorrect MPSS
PCI: Add Solarflare vendor ID and SFC4000 device IDs
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: (83 commits)
mmc: fix compile error when CONFIG_BLOCK is not enabled
mmc: core: Cleanup eMMC4.5 conditionals
mmc: omap_hsmmc: if multiblock reads are broken, disable them
mmc: core: add workaround for controllers with broken multiblock reads
mmc: core: Prevent too long response times for suspend
mmc: recognise SDIO cards with SDIO_CCCR_REV 3.00
mmc: sd: Handle SD3.0 cards not supporting UHS-I bus speed mode
mmc: core: support HPI send command
mmc: core: Add cache control for eMMC4.5 device
mmc: core: Modify the timeout value for writing power class
mmc: core: new discard feature support at eMMC v4.5
mmc: core: mmc sanitize feature support for v4.5
mmc: dw_mmc: modify DATA register offset
mmc: sdhci-pci: add flag for devices that can support runtime PM
mmc: omap_hsmmc: ensure pbias configuration is always done
mmc: core: Add Power Off Notify Feature eMMC 4.5
mmc: sdhci-s3c: fix potential NULL dereference
mmc: replace printk with appropriate display macro
mmc: core: Add default timeout value for CMD6
mmc: sdhci-pci: add runtime pm support
...
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hch/vfs-queue: (21 commits)
leases: fix write-open/read-lease race
nfs: drop unnecessary locking in llseek
ext4: replace cut'n'pasted llseek code with generic_file_llseek_size
vfs: add generic_file_llseek_size
vfs: do (nearly) lockless generic_file_llseek
direct-io: merge direct_io_walker into __blockdev_direct_IO
direct-io: inline the complete submission path
direct-io: separate map_bh from dio
direct-io: use a slab cache for struct dio
direct-io: rearrange fields in dio/dio_submit to avoid holes
direct-io: fix a wrong comment
direct-io: separate fields only used in the submission path from struct dio
vfs: fix spinning prevention in prune_icache_sb
vfs: add a comment to inode_permission()
vfs: pass all mask flags check_acl and posix_acl_permission
vfs: add hex format for MAY_* flag values
vfs: indicate that the permission functions take all the MAY_* flags
compat: sync compat_stats with statfs.
vfs: add "device" tag to /proc/self/mountstats
cleanup: vfs: small comment fix for block_invalidatepage
...
Fix up trivial conflict in fs/gfs2/file.c (llseek changes)
* '3.2-without-smb2' of git://git.samba.org/sfrench/cifs-2.6: (52 commits)
Fix build break when freezer not configured
Add definition for share encryption
CIFS: Make cifs_push_locks send as many locks at once as possible
CIFS: Send as many mandatory unlock ranges at once as possible
CIFS: Implement caching mechanism for posix brlocks
CIFS: Implement caching mechanism for mandatory brlocks
CIFS: Fix DFS handling in cifs_get_file_info
CIFS: Fix error handling in cifs_readv_complete
[CIFS] Fixup trivial checkpatch warning
[CIFS] Show nostrictsync and noperm mount options in /proc/mounts
cifs, freezer: add wait_event_freezekillable and have cifs use it
cifs: allow cifs_max_pending to be readable under /sys/module/cifs/parameters
cifs: tune bdi.ra_pages in accordance with the rsize
cifs: allow for larger rsize= options and change defaults
cifs: convert cifs_readpages to use async reads
cifs: add cifs_async_readv
cifs: fix protocol definition for READ_RSP
cifs: add a callback function to receive the rest of the frame
cifs: break out 3rd receive phase into separate function
cifs: find mid earlier in receive codepath
...
Add a generic_file_llseek variant to the VFS that allows passing in
the maximum file size of the file system, instead of always
using maxbytes from the superblock.
This can be used to eliminate some cut'n'paste seek code in ext4.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The i_mutex lock use of generic _file_llseek hurts. Independent processes
accessing the same file synchronize over a single lock, even though
they have no need for synchronization at all.
Under high utilization this can cause llseek to scale very poorly on larger
systems.
This patch does some rethinking of the llseek locking model:
First the 64bit f_pos is not necessarily atomic without locks
on 32bit systems. This can already cause races with read() today.
This was discussed on linux-kernel in the past and deemed acceptable.
The patch does not change that.
Let's look at the different seek variants:
SEEK_SET: Doesn't really need any locking.
If there's a race one writer wins, the other loses.
For 32bit the non atomic update races against read()
stay the same. Without a lock they can also happen
against write() now. The read() race was deemed
acceptable in past discussions, and I think if it's
ok for read it's ok for write too.
=> Don't need a lock.
SEEK_END: This behaves like SEEK_SET plus it reads
the maximum size too. Reading the maximum size would have the
32bit atomic problem. But luckily we already have a way to read
the maximum size without locking (i_size_read), so we
can just use that instead.
Without i_mutex there is no synchronization with write() anymore,
however since the write() update is atomic on 64bit it just behaves
like another racy SEEK_SET. On non atomic 32bit it's the same
as SEEK_SET.
=> Don't need a lock, but need to use i_size_read()
SEEK_CUR: This has a read-modify-write race window
on the same file. One could argue that any application
doing unsynchronized seeks on the same file is already broken.
But for the sake of not adding a regression here I'm
using the file->f_lock to synchronize this. Using this
lock is much better than the inode mutex because it doesn't
synchronize between processes.
=> So still need a lock, but can use a f_lock.
This patch implements this new scheme in generic_file_llseek.
I dropped generic_file_llseek_unlocked and changed all callers.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
We are going to add more flags and having them in hex format
make it simpler
Acked-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
* 'drm-core-next' of git://people.freedesktop.org/~airlied/linux: (290 commits)
Revert "drm/ttm: add a way to bo_wait for either the last read or last write"
Revert "drm/radeon/kms: add a new gem_wait ioctl with read/write flags"
vmwgfx: Don't pass unused arguments to do_dirty functions
vmwgfx: Emulate depth 32 framebuffers
drm/radeon: Lower the severity of the radeon lockup messages.
drm/i915/dp: Fix eDP on PCH DP on CPT/PPT
drm/i915/dp: Introduce is_cpu_edp()
drm/i915: use correct SPD type value
drm/i915: fix ILK+ infoframe support
drm/i915: add DP test request handling
drm/i915: read full receiver capability field during DP hot plug
drm/i915/dp: Remove eDP special cases from bandwidth checks
drm/i915/dp: Fix the math in intel_dp_link_required
drm/i915/panel: Always record the backlight level again (but cleverly)
i915: Move i915_read/write out of line
drm/i915: remove transcoder PLL mashing from mode_set per specs
drm/i915: if transcoder disable fails, say which
drm/i915: set watermarks for third pipe on IVB
drm/i915: export a CPT mode set verification function
drm/i915: fix transcoder PLL select masking
...
* 'x86-rdrand-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, random: Verify RDRAND functionality and allow it to be disabled
x86, random: Architectural inlines to get random integers with RDRAND
random: Add support for architectural random hooks
Fix up trivial conflicts in drivers/char/random.c: the architectural
random hooks touched "get_random_int()" that was simplified to use MD5
and not do the keyptr thing any more (see commit 6e5714eaf7: "net:
Compute protocol sequence numbers and fragment IDs using MD5").
fs/cifs/transport.c: In function 'wait_for_response':
fs/cifs/transport.c:328: error: implicit declaration of function 'wait_event_freezekillable'
Caused by commit f06ac72e92 ("cifs, freezer: add
wait_event_freezekillable and have cifs use it"). In this config,
CONFIG_FREEZER is not set.
Reviewed-by: Shirish Pargaonkar <shirishp@us.ibm.com>
CC: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
This reverts commit dfadbbdb57.
Further upstream discussion between Marek and Thomas decided this wasn't
fully baked and needed further work, so revert it before it hits mainline.
Signed-off-by: Dave Airlie <airlied@redhat.com>
This reverts commit d3ed74027f.
Further upstream discussion between Thomas and Marek decided this needed
more work and driver specifics. So revert before it goes upstream.
Signed-off-by: Dave Airlie <airlied@redhat.com>
'DISK_NAME_LEN' is undeclared when CONFIG_BLOCK is disabled; its use was
introduced via genhd.h by the general purpose partition patch.
To fix, we just add our own MAX_MMC_PART_NAME_LEN macro instead of using
DISK_NAME_LEN.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Andrei Warkentin <andreiw@vmware.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
