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* mtd: introduce mtd_block_isbad interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_is_locked interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_unlock interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_lock interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_sync interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_lock_user_prot_reg interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_write_user_prot_reg interfaceArtem Bityutskiy2012-01-091-1/+2
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_read_user_prot_reg interfaceArtem Bityutskiy2012-01-091-1/+2
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_get_user_prot_info interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_read_fact_prot_reg interfaceArtem Bityutskiy2012-01-091-1/+2
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_get_fact_prot_info interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_write_oob interfaceArtem Bityutskiy2012-01-091-3/+3
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_read_oob interfaceArtem Bityutskiy2012-01-091-2/+2
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_write interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_read interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_get_unmapped_area interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: introduce mtd_erase interfaceArtem Bityutskiy2012-01-091-1/+1
| | | | | | | | | | | | | | | | | | | This patch is part of a patch-set which changes the MTD interface from 'mtd->func()' form to 'mtd_func()' form. We need this because we want to add common code to to all drivers in the mtd core level, which is impossible with the current interface when MTD clients call driver functions like 'read()' or 'write()' directly. At this point we just introduce a new inline wrapper function, but later some of them are expected to gain more code. E.g., the input parameters check should be moved to the wrappers rather than be duplicated at many drivers. This particular patch introduced the 'mtd_erase()' interface. The following patches add all the other interfaces one by one. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: mtdchar: rename functionsArtem Bityutskiy2012-01-091-37/+39
| | | | | | | | | | | | | | | | We are going to re-work the MTD interface and change 'mtd->write()' to 'mtd_write()', 'mtd->read()' to 'mtd_read()' and so forth for all functions in the 'struct mtd_info' structure. However, mtdchar.c has its own 'mtd_read()', 'mtd_write()', etc functions which collide with our changes. This patch renames these functions to 'mtdchar_read()', 'mtdchar_write()', etc. Additionally, to make the 'mtdchar.c' file look consistent, rename similarly all the other functions starting with 'mtd_'. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* Merge git://git.infradead.org/mtd-2.6Linus Torvalds2011-11-071-42/+120
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.infradead.org/mtd-2.6: (226 commits) mtd: tests: annotate as DANGEROUS in Kconfig mtd: tests: don't use mtd0 as a default mtd: clean up usage of MTD_DOCPROBE_ADDRESS jffs2: add compr=lzo and compr=zlib options jffs2: implement mount option parsing and compression overriding mtd: nand: initialize ops.mode mtd: provide an alias for the redboot module name mtd: m25p80: don't probe device which has status of 'disabled' mtd: nand_h1900 never worked mtd: Add DiskOnChip G3 support mtd: m25p80: add EON flash EN25Q32B into spi flash id table mtd: mark block device queue as non-rotational mtd: r852: make r852_pm_ops static mtd: m25p80: add support for at25df321a spi data flash mtd: mxc_nand: preset_v1_v2: unlock all NAND flash blocks mtd: nand: switch `check_pattern()' to standard `memcmp()' mtd: nand: invalidate cache on unaligned reads mtd: nand: do not scan bad blocks with NAND_BBT_NO_OOB set mtd: nand: wait to set BBT version mtd: nand: scrub BBT on ECC errors ... Fix up trivial conflicts: - arch/arm/mach-at91/board-usb-a9260.c Merged into board-usb-a926x.c - drivers/mtd/maps/lantiq-flash.c add_mtd_partitions -> mtd_device_register vs changed to use mtd_device_parse_register.
| * mtd: utilize `mtd_is_*()' functionsBrian Norris2011-09-211-2/+2
| | | | | | | | | | Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * mtd: kill old field for `struct mtd_info_user'Brian Norris2011-09-111-2/+2
| | | | | | | | | | | | | | | | | | The ecctype and eccsize fields have been obsolete for a while. Since they don't have any users, we can kill them and leave padding in their place for now. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * mtd: add MEMWRITE ioctlBrian Norris2011-09-111-0/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Implement a new ioctl for writing both page data and OOB to flash at the same time. This ioctl is intended to be a generic interface that can replace other ioctls (MEMWRITEOOB and MEMWRITEOOB64) and cover the functionality of several other old ones, e.g., MEMWRITE can: * write autoplaced OOB instead of using ECCGETLAYOUT (deprecated) and working around the reserved areas * write raw (no ECC) OOB instead of using MTDFILEMODE to set the per-file-descriptor MTD_FILE_MODE_RAW * write raw (no ECC) data instead of using MTDFILEMODE (MTD_FILE_MODE_RAW) and using standard character device "write" This ioctl is especially useful for MLC NAND, which cannot be written twice (i.e., we cannot successfully write the page data and OOB in two separate operations). Instead, MEMWRITE can write both in a single operation. Note that this ioctl is not affected by the MTD file mode (i.e., MTD_FILE_MODE_RAW vs. MTD_FILE_MODE_NORMAL), since it receives its write mode as an input parameter. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * mtd: rename MTD_MODE_* to MTD_FILE_MODE_*Brian Norris2011-09-111-18/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These modes hold their state only for the life of their file descriptor, and they overlap functionality with the MTD_OPS_* modes. Particularly, MTD_MODE_RAW and MTD_OPS_RAW cover the same function: to provide raw (i.e., without ECC) access to the flash. In fact, although it may not be clear, MTD_MODE_RAW implied that operations should enable the MTD_OPS_RAW mode. Thus, we should be specific on what each mode means. This is a start, where MTD_FILE_MODE_* actually represents a "file mode," not necessarily a true global MTD mode. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * mtd: rename MTD_OOB_* to MTD_OPS_*Brian Norris2011-09-111-4/+6
| | | | | | | | | | | | | | | | | | | | These modes are not necessarily for OOB only. Particularly, MTD_OOB_RAW affected operations on in-band page data as well. To clarify these options and to emphasize that their effect is applied per-operation, we change the primary prefix to MTD_OPS_. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * mtd: support reading OOB without ECCBrian Norris2011-09-111-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes issues with `nanddump -n' and the MEMREADOOB[64] ioctls on hardware that performs error correction when reading only OOB data. A driver for such hardware needs to know when we're doing a RAW vs. a normal write, but mtd_do_read_oob does not pass such information to the lower layers (e.g., NAND). We should pass MTD_OOB_RAW or MTD_OOB_PLACE based on the MTD file mode. For now, most drivers can get away with just setting: chip->ecc.read_oob_raw = chip->ecc.read_oob This is done by default; but for systems that behave as described above, you must supply your own replacement function. This was tested with nandsim as well as on actual SLC NAND. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Cc: Jim Quinlan <jim2101024@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * mtd: support writing OOB without ECCBrian Norris2011-09-111-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes issues with `nandwrite -n -o' and the MEMWRITEOOB[64] ioctls on hardware that writes ECC when writing OOB. The problem arises as follows: `nandwrite -n' can write page data to flash without applying ECC, but when used with the `-o' option, ECC is applied (incorrectly), contrary to the `--noecc' option. I found that this is the case because my hardware computes and writes ECC data to flash upon either OOB write or page write. Thus, to support a proper "no ECC" write, my driver must know when we're performing a raw OOB write vs. a normal ECC OOB write. However, MTD does not pass any raw mode information to the write_oob functions. This patch addresses the problems by: 1) Passing MTD_OOB_RAW down to lower layers, instead of just defaulting to MTD_OOB_PLACE 2) Handling MTD_OOB_RAW within the NAND layer's `nand_do_write_oob' 3) Adding a new (replaceable) function pointer in struct ecc_ctrl; this function should support writing OOB without ECC data. Current hardware often can use the same OOB write function when writing either with or without ECC This was tested with nandsim as well as on actual SLC NAND. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Cc: Jim Quinlan <jim2101024@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * mtd: do not assume oobsize is power of 2Brian Norris2011-09-111-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previous generations of MTDs all used OOB sizes that were powers of 2, (e.g., 64, 128). However, newer generations of flash, especially NAND, use irregular OOB sizes that are not powers of 2 (e.g., 218, 224, 448). This means we cannot use masks like "mtd->oobsize - 1" to assume that we will get a proper bitmask for OOB operations. These masks are really only intended to hide the "page" portion of the offset, leaving any OOB offset intact, so a masking with the writesize (which *is* always a power of 2) is valid and makes more sense. This has been tested for read/write of NAND devices (nanddump/nandwrite) using nandsim and actual NAND flash. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * mtd: spelling fixesBrian Norris2011-09-111-2/+2
| | | | | | | | | | Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * mtd: replace DEBUG() with pr_debug()Brian Norris2011-09-111-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Start moving away from the MTD_DEBUG_LEVEL messages. The dynamic debugging feature is a generic kernel feature that provides more flexibility. (See Documentation/dynamic-debug-howto.txt) Also fix some punctuation, indentation, and capitalization that went along with the affected lines. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * mtd: edit NAND-related commentBrian Norris2011-09-111-2/+3
| | | | | | | | | | | | | | | | | | | | This comment was unclear regarding which NAND functions do and do not support ECC on the spare area. This update should reflect the current status of the NAND system but can be updated if changes are made in the standard functions. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <dedekind1@gmail.com>
| * mtd: nand: handle ECC errors in OOBBrian Norris2011-09-111-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While the standard NAND OOB functions do not do ECC on the spare area, it is possible for a driver to supply its own OOB ECC functions (e.g., HW ECC). nand_do_read_oob should act like nand_do_read_ops in checking the ECC stats and returning -EBADMSG or -EUCLEAN on uncorrectable errors or correctable bitflips, respectively. These error codes could be used in flash-based BBT code or in YAFFS, for example. Doing this, however, messes with the behavior of mtd_do_readoob. Now, mtd_do_readoob should check whether we had -EUCLEAN or -EBADMSG errors and discard those as "non-fatal" so that the ioctls can still succeed with (possibly uncorrected) data. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
| * mtd: spelling, capitalization, uniformityBrian Norris2011-09-111-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Therefor -> Therefore [Intern], [Internal] -> [INTERN] [REPLACABLE] -> [REPLACEABLE] syndrom, syndom -> syndrome ecc -> ECC buswith -> buswidth endianess -> endianness dont -> don't occures -> occurs independend -> independent wihin -> within erease -> erase blockes -> blocks ... Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
| * mtd: mtdchar: add missing initializer on raw writePeter Wippich2011-09-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | On writes in MODE_RAW the mtd_oob_ops struct is not sufficiently initialized which may cause nandwrite to fail. With this patch it is possible to write raw nand/oob data without additional ECC (either for testing or when some sectors need different oob layout e.g. bootloader) like nandwrite -n -r -o /dev/mtd0 <myfile> Signed-off-by: Peter Wippich <pewi@gw-instruments.de> Cc: stable@kernel.org Tested-by: Ricard Wanderlof <ricardw@axis.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* | filesystems: add missing nlink wrappersMiklos Szeredi2011-11-021-1/+1
|/ | | | | | | Replace direct i_nlink updates with the respective updater function (inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* VFS : mount lock scalability for internal mountsTim Chen2011-07-241-1/+1
| | | | | | | | | | | | | | | | | | | For a number of file systems that don't have a mount point (e.g. sockfs and pipefs), they are not marked as long term. Therefore in mntput_no_expire, all locks in vfs_mount lock are taken instead of just local cpu's lock to aggregate reference counts when we release reference to file objects. In fact, only local lock need to have been taken to update ref counts as these file systems are in no danger of going away until we are ready to unregister them. The attached patch marks file systems using kern_mount without mount point as long term. The contentions of vfs_mount lock is now eliminated. Before un-registering such file system, kern_unmount should be called to remove the long term flag and make the mount point ready to be freed. Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* mtd: kill CONFIG_MTD_PARTITIONSJamie Iles2011-05-251-5/+0
| | | | | | | | | Now that none of the drivers use CONFIG_MTD_PARTITIONS we can remove it from Kconfig and the last remaining uses. Signed-off-by: Jamie Iles <jamie@jamieiles.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* mtd: mtdchar: retry large buffer allocationsGrant Erickson2011-05-251-27/+23
| | | | | | | | | | | | | Replace direct call to kmalloc for a potentially large, contiguous buffer allocation with one to mtd_kmalloc_up_to which helps ensure the operation can succeed under low-memory, highly- fragmented situations albeit somewhat more slowly. Signed-off-by: Grant Erickson <marathon96@gmail.com> Tested-by: Ben Gardiner <bengardiner@nanometrics.ca> Tested-by: Stefano Babic <sbabic@denx.de> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* Fix common misspellingsLucas De Marchi2011-03-311-1/+1
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* Merge git://git.infradead.org/mtd-2.6Linus Torvalds2011-01-171-5/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.infradead.org/mtd-2.6: (59 commits) mtd: mtdpart: disallow reading OOB past the end of the partition mtd: pxa3xx_nand: NULL dereference in pxa3xx_nand_probe UBI: use mtd->writebufsize to set minimal I/O unit size mtd: initialize writebufsize in the MTD object of a partition mtd: onenand: add mtd->writebufsize initialization mtd: nand: add mtd->writebufsize initialization mtd: cfi: add writebufsize initialization mtd: add writebufsize field to mtd_info struct mtd: OneNAND: OMAP2/3: prevent regulator sleeping while OneNAND is in use mtd: OneNAND: add enable / disable methods to onenand_chip mtd: m25p80: Fix JEDEC ID for AT26DF321 mtd: txx9ndfmc: limit transfer bytes to 512 (ECC provides 6 bytes max) mtd: cfi_cmdset_0002: add support for Samsung K8D3x16UxC NOR chips mtd: cfi_cmdset_0002: add support for Samsung K8D6x16UxM NOR chips mtd: nand: ams-delta: drop omap_read/write, use ioremap mtd: m25p80: add debugging trace in sst_write mtd: nand: ams-delta: select for built-in by default mtd: OneNAND: lighten scary initial bad block messages mtd: OneNAND: OMAP2/3: add support for command line partitioning mtd: nand: rearrange ONFI revision checking, add ONFI 2.3 ... Fix up trivial conflict in drivers/mtd/Kconfig as per DavidW.
| * mtd: fix master device identification for mtd repartitionRoman Tereshonkov2010-12-031-4/+4
| | | | | | | | | | | | | | | | | | | | | | Function mtd_has_master renamed as mtd_is_partition to follow the function logic. The patch fixes the problem of checking the right mtd device for partition creation. To delete partition checking is not needed here so as it is done in mtd_del_partition. By master we consider the mtd device which does not belong to any partition. Signed-off-by: Roman Tereshonkov <roman.tereshonkov@nokia.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
| * mtd: mtdchar: fix information leak to userlandVasiliy Kulikov2010-12-031-1/+1
| | | | | | | | | | | | | | | | | | | | Structure mtd_info_user is copied to userland with padding byted between "type" and "flags" fields uninitialized. It leads to leaking of contents of kernel stack memory. Signed-off-by: Vasiliy Kulikov <segooon@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* | sanitize vfsmount refcounting changesAl Viro2011-01-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Instead of splitting refcount between (per-cpu) mnt_count and (SMP-only) mnt_longrefs, make all references contribute to mnt_count again and keep track of how many are longterm ones. Accounting rules for longterm count: * 1 for each fs_struct.root.mnt * 1 for each fs_struct.pwd.mnt * 1 for having non-NULL ->mnt_ns * decrement to 0 happens only under vfsmount lock exclusive That allows nice common case for mntput() - since we can't drop the final reference until after mnt_longterm has reached 0 due to the rules above, mntput() can grab vfsmount lock shared and check mnt_longterm. If it turns out to be non-zero (which is the common case), we know that this is not the final mntput() and can just blindly decrement percpu mnt_count. Otherwise we grab vfsmount lock exclusive and do usual decrement-and-check of percpu mnt_count. For fs_struct.c we have mnt_make_longterm() and mnt_make_shortterm(); namespace.c uses the latter in places where we don't already hold vfsmount lock exclusive and opencodes a few remaining spots where we need to manipulate mnt_longterm. Note that we mostly revert the code outside of fs/namespace.c back to what we used to have; in particular, normal code doesn't need to care about two kinds of references, etc. And we get to keep the optimization Nick's variant had bought us... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | pass default dentry_operations to mount_pseudo()Al Viro2011-01-131-1/+1
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | fs: scale mntget/mntputNick Piggin2011-01-071-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The problem that this patch aims to fix is vfsmount refcounting scalability. We need to take a reference on the vfsmount for every successful path lookup, which often go to the same mount point. The fundamental difficulty is that a "simple" reference count can never be made scalable, because any time a reference is dropped, we must check whether that was the last reference. To do that requires communication with all other CPUs that may have taken a reference count. We can make refcounts more scalable in a couple of ways, involving keeping distributed counters, and checking for the global-zero condition less frequently. - check the global sum once every interval (this will delay zero detection for some interval, so it's probably a showstopper for vfsmounts). - keep a local count and only taking the global sum when local reaches 0 (this is difficult for vfsmounts, because we can't hold preempt off for the life of a reference, so a counter would need to be per-thread or tied strongly to a particular CPU which requires more locking). - keep a local difference of increments and decrements, which allows us to sum the total difference and hence find the refcount when summing all CPUs. Then, keep a single integer "long" refcount for slow and long lasting references, and only take the global sum of local counters when the long refcount is 0. This last scheme is what I implemented here. Attached mounts and process root and working directory references are "long" references, and everything else is a short reference. This allows scalable vfsmount references during path walking over mounted subtrees and unattached (lazy umounted) mounts with processes still running in them. This results in one fewer atomic op in the fastpath: mntget is now just a per-CPU inc, rather than an atomic inc; and mntput just requires a spinlock and non-atomic decrement in the common case. However code is otherwise bigger and heavier, so single threaded performance is basically a wash. Signed-off-by: Nick Piggin <npiggin@kernel.dk>
* Merge git://git.infradead.org/mtd-2.6Linus Torvalds2010-10-301-5/+106
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.infradead.org/mtd-2.6: (82 commits) mtd: fix build error in m25p80.c mtd: Remove redundant mutex from mtd_blkdevs.c MTD: Fix wrong check register_blkdev return value Revert "mtd: cleanup Kconfig dependencies" mtd: cfi_cmdset_0002: make sector erase command variable mtd: cfi_cmdset_0002: add CFI detection for SST 38VF640x chips mtd: cfi_util: add support for switching SST 39VF640xB chips into QRY mode mtd: cfi_cmdset_0001: use defined value of P_ID_INTEL_PERFORMANCE instead of hardcoded one block2mtd: dubious assignment P4080/mtd: Fix the freescale lbc issue with 36bit mode P4080/eLBC: Make Freescale elbc interrupt common to elbc devices mtd: phram: use KBUILD_MODNAME mtd: OneNAND: S5PC110: Fix double call suspend & resume function mtd: nand: fix MTD_MODE_RAW writes jffs2: use kmemdup mtd: sm_ftl: cosmetic, use bool when possible mtd: r852: remove useless pci powerup/down from suspend/resume routines mtd: blktrans: fix a race vs kthread_stop mtd: blktrans: kill BKL mtd: allow to unload the mtdtrans module if its block devices aren't open ... Fix up trivial whitespace-introduced conflict in drivers/mtd/mtdchar.c
| * Merge branch 'master' of ↵David Woodhouse2010-10-301-7/+8
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git Conflicts: drivers/mtd/mtd_blkdevs.c Merge Grant's device-tree bits so that we can apply the subsequent fixes. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
| * | mtd: add BLKPG API based repartition supportRoman Tereshonkov2010-10-251-2/+58
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add support for mtd repartition based on the block device BLKPG interface: BLKPG_ADD_PARTITION - for partition creation; BLKPG_DEL_PARTITION - for partition delete The usage is based on BLKPG ioctl called with struct blkpg_ioctl_arg argument which includes the reference to struct blkpg_partition discribing the partition offset and length. Disadvantage: there is no implementation for mtd flags control. The flags are always borrowed from the master device. Signed-off-by: Roman Tereshonkov <roman.tereshonkov@nokia.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
| * | mtd: sanity check ioctl inputDan Carpenter2010-10-251-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If "ur_idx" is wrong we could go past the end of the array. The "ur_idx" comes from root so it's not a huge deal, but adding a sanity check makes the code more robust. Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
| * | mtd: edit comments on deprecation of ioctl ECCGETLAYOUTBrian Norris2010-10-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There were some improvements and additions necessary in the comments explaining of the expansion of nand_ecclayout, the introduction of nand_ecclayout_user, and the deprecation of the ioctl ECCGETLAYOUT. Also, I found a better placement for the macro MTD_MAX_ECCPOS_ENTRIES; next to the definition of MTD_MAX_OOBFREE_ENTRIES in mtd-abi.h. The macro is really only important for the ioctl code (found in drivers/mtd/mtdchar.c) but since there are small edits being made to the user-space header, I figured this is a better location. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
| * | mtd: nand: expand nand_ecc_layout, deprecate ioctl ECCGETLAYOUTBrian Norris2010-10-251-3/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | struct nand_ecclayout is too small for many new chips; OOB regions can be as large as 448 bytes and may increase more in the future. Thus, copying that struct to user-space with the ECCGETLAYOUT ioctl is not a good idea; the ioctl would have to be updated every time there's a change to the current largest size. Instead, the old nand_ecclayout is renamed to nand_ecclayout_user and a new struct nand_ecclayout is created that can accomodate larger sizes and expand without affecting the user-space. struct nand_ecclayout can still be used in board drivers without modification -- at least for now. A new function is provided to convert from the new to the old in order to allow the deprecated ioctl to continue to work with truncated data. Perhaps the ioctl, the conversion process, and the struct nand_ecclayout_user can be removed altogether in the future. Note: There are comments in nand/davinci_nand.c::nand_davinci_probe() regarding this issue; this driver (and maybe others) can be updated to account for extra space. All kernel drivers can use the expanded nand_ecclayout as a drop-in replacement and ignore its benefits. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
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