mmc_rescan() includes a pr_info which prints 4 lines each second for
hosts configured with MMC_CAP_NEEDS_POLL. This patch enables the message
only if CONFIG_MMC_DEBUG is selected. Tested on i.MX51's sdhci-esdhc.
Signed-off-by: Eric Bénard <eric@eukrea.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Hein Tibosch <hein_tibosch@yahoo.es>
Signed-off-by: Chris Ball <cjb@laptop.org>
In the latest releases of the mmc driver, the freq during initialization
is set to a fixed 400 Khz. This was reportedly too fast for several
users. As there doesn't seem to be an ideal frequency
which-works-for-all, Pierre suggested to let the driver try several
frequencies.
This patch implements that idea. It will try mmc-initialization using
several frequencies from an array 400, 300, 200 and 100.
In case SDIO is broken, it'll still try to detect SDMEM, also at different
freqs.
Signed-off-by: Hein Tibosch <hein_tibosch@yahoo.es>
Cc: Pierre Ossman <pierre@ossman.eu>
Reviewed-by: Chris Ball <cjb@laptop.org>
Tested-by: Chris Ball <cjb@laptop.org>
Cc: Ben Nizette <bn@niasdigital.com>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Adrian Hunter <adrian.hunter@nokia.com>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
When a controller requires SDHCI_QUIRK_BROKEN_CARD_DETECTION, we poll
for card insertion/removal, and that creates interrupts. There's no
need to be doing this if we have a non-removable card.
This patch requires cards to be removable before we're willing to set
MMC_CAP_NEEDS_POLL.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
[cjb: modified changelog and code indentation]
Signed-off-by: Chris Ball <cjb@laptop.org>
There are two checks that need to be made when determining whether a
card is removable. A host controller may set MMC_CAP_NONREMOVABLE if the
controller does not support removing cards (e.g. eMMC), in which case
the card is physically non-removable. Also the 'mmc_assume_removable'
module parameter can be configured at module load time, in which case
the card may be logically non-removable.
A helper function keeps the logic in one place so that code always
checks both conditions.
Because this new function is likely to be called from modules we now
need to export the mmc_assume_removable symbol.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Tested-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
The EXTRA_CFLAGS assignment in mmc/Makefile was not accomplishing
anything because this flag only has effect on sources at the same level
as the makefile (i.e., per directory). Since card/, core/, and host/
rely on MMC_DEBUG, the subdir-ccflags-y variant seems to be the
appropriate choice.
Signed-off-by: matt mooney <mfm@muteddisk.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
In a multi-controller environment it is helpful to know which controller
has problems.
Signed-off-by: Philip Rakity <prakity@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
This patch is necessary to gain the performance boost from 8-bit data
with the sdhci-stm driver.
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
MMC_CAP_MMC_HIGHSPEED allows MMC and eMMC to negotiate up to 50M
instead of the previous limit of 25M.
Signed-off-by: Zhangfei Gao <zgao6@marvell.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Acked-by: Kyungmin Park <kmpark@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
While we're at it, add symbols for SDHCI_MAX_DIV_SPEC_{200,300}.
Signed-off-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
SDHC Spec 3.0: Capabilities Register bits[15-08] are Base Clock Frequency
1.0/2.0: Capabilities Register bits[13-08] are Base Clock Frequency
Signed-off-by: Zhangfei Gao <zgao6@marvell.com>
Cc: David Vrabel <david.vrabel@csr.com>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: Michal Miroslaw <mirqus@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Zhangfei Gao <zgao6@marvell.com>
Cc: Michał Mirosław <mirqus@gmail.com>
Cc: David Vrabel <david.vrabel@csr.com>
Reviewed-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
The "6882a8c sdhci: Add better ADMA error reporting" commit added
sdhci_show_adma_error() which is built when DEBUG is defined. Since we
already have CONFIG_MMC_DEBUG used elsewhere in this driver, may as well
make consistent use of that config knob instead.
Signed-off-by: George G. Davis <gdavis@mvista.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Append .5 to KiB display when there are an odd number of sectors.
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Correctly allocate memory to meet the host controller
driver's maximum segment size and count limits.
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
As proposed by Greg K-H it is more logical to keep files for the mmc_test
driver under debugfs.
Additionally this patch brings seq_file API for show() method. It allows
to write unlimited data to the file.
Example of usage:
# mount -t debugfs none /sys/kernel/debug
# modprobe mmc_test
[ 581.395843] mmc_test mmc0:0001: Card claimed for testing.
# echo 25 > /sys/kernel/debug/mmc0/mmc0\:0001/test
[ 604.568542] mmc0: Starting tests of card mmc0:0001...
[ 604.582733] mmc0: Test case 25. Best-case read performance into scattered pages...
[ 604.923553] mmc0: Transfer of 8192 sectors (4096 KiB) took 0.124664314 seconds (33644 kB/s, 32856 KiB/s)
[ 604.933227] mmc0: Result: OK
[ 604.936248] mmc0: Tests completed.
# cat /sys/kernel/debug/mmc0/mmc0\:0001/test
Test 25: 0
1 8192 0.124664314 33644784
Signed-off-by: Andy Shevchenko <ext-andriy.shevchenko@nokia.com>
Cc: Greg KH <greg@kroah.com>
Cc: Adrian Hunter <adrian.hunter@nokia.com>
Cc: Chris Ball <cjb@laptop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Make it possible to get test results via sysfs. It helps to do tests
non-interactively. We have the file created under sysfs already and
can use it to show test results.
Prior to this patch, the "test" file under each card's sysfs node was
write-only, and results were obtained by looking at dmesg. This patch
improves programmatic access to the test results, making them available by
reading back from the same "test" file:
[root@host mmc0:e624]# echo 6 > test
[root@host mmc0:e624]# cat test
Test 6: 2
[cjb@laptop.org: changelog improvements]
Signed-off-by: Andy Shevchenko <ext-andriy.shevchenko@nokia.com>
Cc: Chris Ball <cjb@laptop.org>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
It's better to use strict_strtol() to convert user's input and strictly
check it. At least it forbids to interpret wrong input as a 0 and
prevents to run all tests.
Signed-off-by: Andy Shevchenko <ext-andriy.shevchenko@nokia.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
There are methods to check card type. Let's use them instead of direct checking
type bits.
Signed-off-by: Andy Shevchenko <ext-andriy.shevchenko@nokia.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
The host controller driver limits I/O transfers to maximum
transfer size, maximum block count, maximum segment size
and maximum segment count. The performance tests were
not obeying these limits which meant they would not work
with some drivers. This patch fixes that.
Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Get rid of init_MUTEX[_LOCKED]() and use sema_init() instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mmc@vger.kernel.org
Signed-off-by: Chris Ball <cjb@laptop.org>
Global symbols should use their subsystem name in a prefixed fashion.
Signed-off-by: Andy Shevchenko <ext-andriy.shevchenko@nokia.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Conversion from struct device to struct mmc_card is used more than in one
place. Due to this it's better to have public macro for such thing.
Signed-off-by: Andy Shevchenko <ext-andriy.shevchenko@nokia.com>
Cc: Adrian Hunter <adrian.hunter@nokia.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Fix an issue found by klockwork. Just paranoia.
Signed-off-by: JiebingLi <jiebing.li@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Add a driver for USB SD Host Controller devices. These devices are
Cypress Astoria chips with firmware compliant with issue 2 of CSR's USHC
specification.
[cjb: adapt to block layer deprecation of max_{hw,phys}_segs]
Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
We have deprecated the distinction between hardware and physical
segments in the block layer. Consolidate the two limits into one in
drivers/mmc/.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
[cjb: rebased patch against Linus]
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: <linux-mmc@vger.kernel.org>
Acked-by: Manuel Lauss <manuel.lauss@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
[cjb: rebased patch against Linus]
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ryusuke/nilfs2: (36 commits)
nilfs2: eliminate sparse warning - "context imbalance"
nilfs2: eliminate sparse warnings - "symbol not declared"
nilfs2: get rid of bdi from nilfs object
nilfs2: change license of exported header file
nilfs2: add bdev freeze/thaw support
nilfs2: accept 64-bit checkpoint numbers in cp mount option
nilfs2: remove own inode allocator and destructor for metadata files
nilfs2: get rid of back pointer to writable sb instance
nilfs2: get rid of mi_nilfs back pointer to nilfs object
nilfs2: see state of root dentry for mount check of snapshots
nilfs2: use iget for all metadata files
nilfs2: get rid of GCDAT inode
nilfs2: add routines to redirect access to buffers of DAT file
nilfs2: add routines to roll back state of DAT file
nilfs2: add routines to save and restore bmap state
nilfs2: do not allocate nilfs_mdt_info structure to gc-inodes
nilfs2: allow nilfs_clear_inode to clear metadata file inodes
nilfs2: get rid of snapshot mount flag
nilfs2: simplify life cycle management of nilfs object
nilfs2: do not allocate multiple super block instances for a device
...
* 'x86-trampoline-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86-32, mm: Add an initial page table for core bootstrapping
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
kdb,debug_core: adjust master cpu switch logic against new debug_core locking
debug_core: refactor locking for master/slave cpus
x86,kgdb: remove unnecessary call to kgdb_correct_hw_break()
debug_core: disable hw_breakpoints on all cores in kgdb_cpu_enter()
kdb,kgdb: fix sparse fixups
kdb: Fix oops in kdb_unregister
kdb,ftdump: Remove reference to internal kdb include
kdb: Allow kernel loadable modules to add kdb shell functions
debug_core: stop rcu warnings on kernel resume
debug_core: move all watch dog syncs to a single function
x86,kgdb: fix debugger hw breakpoint test regression in 2.6.35
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (141 commits)
USB: mct_u232: fix broken close
USB: gadget: amd5536udc.c: fix error path
USB: imx21-hcd - fix off by one resource size calculation
usb: gadget: fix Kconfig warning
usb: r8a66597-udc: Add processing when USB was removed.
mxc_udc: add workaround for ENGcm09152 for i.MX35
USB: ftdi_sio: add device ids for ScienceScope
USB: musb: AM35x: Workaround for fifo read issue
USB: musb: add musb support for AM35x
USB: AM35x: Add musb support
usb: Fix linker errors with CONFIG_PM=n
USB: ohci-sh - use resource_size instead of defining its own resource_len macro
USB: isp1362-hcd - use resource_size instead of defining its own resource_len macro
USB: isp116x-hcd - use resource_size instead of defining its own resource_len macro
USB: xhci: Fix compile error when CONFIG_PM=n
USB: accept some invalid ep0-maxpacket values
USB: xHCI: PCI power management implementation
USB: xHCI: bus power management implementation
USB: xHCI: port remote wakeup implementation
USB: xHCI: port power management implementation
...
Manually fix up (non-data) conflict: the SCSI merge gad renamed the
'hw_sector_size' member to 'physical_block_size', and the USB tree
brought a new use of it.
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (49 commits)
serial8250: ratelimit "too much work" error
serial: bfin_sport_uart: speed up sport RX sample rate to be 3% faster
serial: abstraction for 8250 legacy ports
serial/imx: check that the buffer is non-empty before sending it out
serial: mfd: add more baud rates support
jsm: Remove the uart port on errors
Alchemy: Add UART PM methods.
8250: allow platforms to override PM hook.
altera_uart: Don't use plain integer as NULL pointer
altera_uart: Fix missing prototype for registering an early console
altera_uart: Fixup type usage of port flags
altera_uart: Make it possible to use Altera UART and 8250 ports together
altera_uart: Add support for different address strides
altera_uart: Add support for getting mapbase and IRQ from resources
altera_uart: Add support for polling mode (IRQ-less)
serial: Factor out uart_poll_timeout() from 8250 driver
serial: mark the 8250 driver as maintained
serial: 8250: Don't delay after transmitter is ready.
tty: MAINTAINERS: add drivers/serial/jsm/ as maintained driver
vcs: invoke the vt update callback when /dev/vcs* is written to
...
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (31 commits)
driver core: Display error codes when class suspend fails
Driver core: Add section count to memory_block struct
Driver core: Add mutex for adding/removing memory blocks
Driver core: Move find_memory_block routine
hpilo: Despecificate driver from iLO generation
driver core: Convert link_mem_sections to use find_memory_block_hinted.
driver core: Introduce find_memory_block_hinted which utilizes kset_find_obj_hinted.
kobject: Introduce kset_find_obj_hinted.
driver core: fix build for CONFIG_BLOCK not enabled
driver-core: base: change to new flag variable
sysfs: only access bin file vm_ops with the active lock
sysfs: Fail bin file mmap if vma close is implemented.
FW_LOADER: fix kconfig dependency warning on HOTPLUG
uio: Statically allocate uio_class and use class .dev_attrs.
uio: Support 2^MINOR_BITS minors
uio: Cleanup irq handling.
uio: Don't clear driver data
uio: Fix lack of locking in init_uio_class
SYSFS: Allow boot time switching between deprecated and modern sysfs layout
driver core: remove CONFIG_SYSFS_DEPRECATED_V2 but keep it for block devices
...
Commit dd3932eddf ("block: remove BLKDEV_IFL_WAIT") had removed the
flag argument to blkdev_issue_flush(), but the ocfs2 merge brought in a
new one. It didn't cause a merge conflict, so the merges silently
worked out fine, but the result didn't actually compile.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: (56 commits)
[CIFS] move close processing from cifs_close to cifsFileInfo_put
cifs: convert cifs_tcp_ses_lock from a rwlock to a spinlock
cifs: cancel_delayed_work() + flush_scheduled_work() -> cancel_delayed_work_sync()
Clean up two declarations of blob_len
cifs: move cifsFileInfo_put to file.c
cifs: convert GlobalSMBSeslock from a rwlock to regular spinlock
[CIFS] Fix minor checkpatch warning and update cifs version
cifs: move cifs_new_fileinfo to file.c
cifs: eliminate pfile pointer from cifsFileInfo
cifs: cifs_write argument change and cleanup
cifs: clean up cifs_reopen_file
cifs: eliminate the inode argument from cifs_new_fileinfo
cifs: eliminate oflags option from cifs_new_fileinfo
cifs: fix flags handling in cifs_posix_open
cifs: eliminate cifs_posix_open_inode_helper
cifs: handle FindFirst failure gracefully
NTLM authentication and signing - Calculate auth response per smb session
cifs: don't use vfsmount to pin superblock for oplock breaks
cifs: keep dentry reference in cifsFileInfo instead of inode reference
cifs: on multiuser mount, set ownership to current_fsuid/current_fsgid (try #7)
...
Fix up trivial conflict in fs/cifs/cifsfs.c due to added/removed header files
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/dlm:
dlm: Fix dlm lock status block comment in dlm.h
dlm: Don't send callback to node making lock request when "try 1cb" fails
* 'for-linus' of git://oss.sgi.com/xfs/xfs: (36 commits)
xfs: semaphore cleanup
xfs: Extend project quotas to support 32bit project ids
xfs: remove xfs_buf wrappers
xfs: remove xfs_cred.h
xfs: remove xfs_globals.h
xfs: remove xfs_version.h
xfs: remove xfs_refcache.h
xfs: fix the xfs_trans_committed
xfs: remove unused t_callback field in struct xfs_trans
xfs: fix bogus m_maxagi check in xfs_iget
xfs: do not use xfs_mod_incore_sb_batch for per-cpu counters
xfs: do not use xfs_mod_incore_sb for per-cpu counters
xfs: remove XFS_MOUNT_NO_PERCPU_SB
xfs: pack xfs_buf structure more tightly
xfs: convert buffer cache hash to rbtree
xfs: serialise inode reclaim within an AG
xfs: batch inode reclaim lookup
xfs: implement batched inode lookups for AG walking
xfs: split out inode walk inode grabbing
xfs: split inode AG walking into separate code for reclaim
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu: update comments to reflect that percpu allocations are always zero-filled
percpu: Optimize __get_cpu_var()
x86, percpu: Optimize this_cpu_ptr
percpu: clear memory allocated with the km allocator
percpu: fix build breakage on s390 and cleanup build configuration tests
percpu: use percpu allocator on UP too
percpu: reduce PCPU_MIN_UNIT_SIZE to 32k
vmalloc: pcpu_get/free_vm_areas() aren't needed on UP
Fixed up trivial conflicts in include/linux/percpu.h
insert sparse annotations to fix following sparse warning.
fs/nilfs2/segment.c:2681:3: warning: context imbalance in 'nilfs_segctor_kill_thread' - unexpected unlock
nilfs_segctor_kill_thread is only called inside sc_state_lock lock.
sparse doesn't detect the context and warn "unexpected unlock".
__acquires/__releases pretend to lock/unlock the sc_state_lock for sparse.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
change nilfs_dat_commit_free and nilfs_inode_cachep static
to fix following warnings
fs/nilfs2/super.c:72:19: warning: symbol 'nilfs_inode_cachep' was not declared. Should it be static?
fs/nilfs2/dat.c:106:6: warning: symbol 'nilfs_dat_commit_free' was not declared. Should it be static?
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Nilfs now can use sb->s_bdi to get backing_dev_info, so we use it
instead of ns_bdi on the nilfs object and remove ns_bdi.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This allows other projects to carry copies of the header file related
to ABI and disk format (i.e. "nilfs2_fs.h") without it or distributors
having to worry about effects on the project's overall license terms.
It's also desired for switching the license of nilfs library to LGPL.
Jiro SEKIBA pointed out these license issues (Message-ID:
<87tylo7msw.wl%jir@sekiba.com>), and he suggested switching license of
the library and nilfs2_fs.h to GNU Lesser General Public License. We
take in his suggestion to avoid the license issues.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Jiro SEKIBA <jir@unicus.jp>
Cc: linux-nilfs <linux-nilfs@vger.kernel.org>
Nilfs hasn't supported the freeze/thaw feature because it didn't work
due to the peculiar design that multiple super block instances could
be allocated for a device. This limitation was removed by the patch
"nilfs2: do not allocate multiple super block instances for a device".
So now this adds the freeze/thaw support to nilfs.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
The current implementation doesn't mount snapshots with checkpoint
numbers larger than INT_MAX since it uses match_int() for parsing
"cp=" mount option.
This uses simple_strtoull() for the conversion to resolve the issue.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
This finally removes own inode allocator and destructor functions for
metadata files. Several routines, nilfs_mdt_new(),
nilfs_mdt_new_common(), nilfs_mdt_clear(), nilfs_mdt_destroy(), and
nilfs_alloc_inode_common() will be gone.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Nilfs object holds a back pointer to a writable super block instance
in nilfs->ns_writer, and this became eliminable since sb is now made
per device and all inodes have a valid pointer to it.
This deletes the ns_writer pointer and a reader/writer semaphore
protecting it.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>