summaryrefslogtreecommitdiffstats
path: root/drivers/staging/zram
Commit message (Collapse)AuthorAgeFilesLines
* Merge 3.8-rc5 into staging-nextGreg Kroah-Hartman2013-01-261-12/+22
|\ | | | | | | | | | | This resolves a merge issue with a iio driver, and the zram code. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * staging: zram: fix invalid memory references during disk writeNitin Gupta2013-01-141-15/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixes a bug introduced by commit c8f2f0db1 ("zram: Fix handling of incompressible pages") which caused invalid memory references during disk write. Invalid references could occur in two cases: - Incoming data expands on compression: In this case, reference was made to kunmap()'ed bio page. - Partial (non PAGE_SIZE) write with incompressible data: In this case, reference was made to a kfree()'ed buffer. Fixes bug 50081: https://bugzilla.kernel.org/show_bug.cgi?id=50081 Signed-off-by: Nitin Gupta <ngupta@vflare.org> Cc: stable <stable@vger.kernel.org> Reported-by: Mihail Kasadjikov <hamer.mk@gmail.com> Reported-by: Tomas M <tomas@slax.org> Reviewed-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | staging: zram: drop zram_stat_dec/inc functionsDavidlohr Bueso2013-01-161-18/+8Star
| | | | | | | | | | | | | | | | It seems like an overkill to have adding and subtracting 1 functions from the 32bit counters. Just do it directly. Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | staging: zram: show correct disksizeDavidlohr Bueso2013-01-161-2/+1Star
| | | | | | | | | | | | | | | | The ->disksize variable stores values in units of bytes, print the correct size in Kb Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | staging: zram: simplify num_devices paramaterDavidlohr Bueso2013-01-161-7/+3Star
| | | | | | | | | | | | | | | | Simplify dealing with num_devices when initializing zram. Also cleanup some of the output messages. Signed-off-by: Davidlohr Bueso <davidlohr.bueso@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | staging: Add angle bracket before and after the URLMasanari Iida2013-01-071-1/+1
|/ | | | | | | Add missing angle bracket before and after the URL. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* staging: zram: handle mem suffixes in disk size zram_sysfs parameterSergey Senozhatsky2012-10-311-4/+4
| | | | | | | | | | | | Use memparse() to allow mem suffixes in disksize sysfs number. Examples: echo 256K > /sys/block/zram0/disksize echo 512M > /sys/block/zram0/disksize echo 1G > /sys/block/zram0/disksize Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* staging: zram: factor-out zram_decompress_page() functionSergey Senozhatsky2012-10-311-65/+48Star
| | | | | | | | | | zram_bvec_read() shared decompress functionality with zram_read_before_write() function. Factor-out and make commonly used zram_decompress_page() function, which also simplified error handling in zram_bvec_read(). Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge 3.7-rc3 into staging-nextGreg Kroah-Hartman2012-10-291-2/+10
|\ | | | | | | | | | | | | | | | | This resolves the conflict with: drivers/staging/comedi/drivers/amplc_dio200.c and syncs up the changes that happened in the staging directory for 3.7-rc3. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * staging: zram: Fix handling of incompressible pagesNitin Gupta2012-10-221-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change 130f315a (staging: zram: remove special handle of uncompressed page) introduced a bug in the handling of incompressible pages which resulted in memory allocation failure for such pages. When a page expands on compression, say from 4K to 4K+30, we were trying to do zsmalloc(pool, 4K+30). However, the maximum size which zsmalloc can allocate is PAGE_SIZE (for obvious reasons), so such allocation requests always return failure (0). For a page that has compressed size larger than the original size (this may happen with already compressed or random data), there is no point storing the compressed version as that would take more space and would also require time for decompression when needed again. So, the fix is to store any page, whose compressed size exceeds a threshold (max_zpage_size), as-it-is i.e. without compression. Memory required for storing this uncompressed page can then be requested from zsmalloc which supports PAGE_SIZE sized allocations. Lastly, the fix checks that we do not attempt to "decompress" the page which we stored in the uncompressed form -- we just memcpy() out such pages. Signed-off-by: Nitin Gupta <ngupta@vflare.org> Reported-by: viechweg@gmail.com Reported-by: paerley@gmail.com Reported-by: wu.tommy@gmail.com Acked-by: Minchan Kim <minchan@kernel.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | staging: zram: correct obsolete comment on max_zpage_sizeMinchan Kim2012-10-221-2/+2
|/ | | | | | | | Zram doesn't use xv_malloc any more so it doesn't have limitation about zobj_header. Signed-off-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* staging: zsmalloc: add mapping modesSeth Jennings2012-07-091-3/+4
| | | | | | | | | | This patch improves mapping performance in zsmalloc by getting usage information from the user in the form of a "mapping mode" and using it to avoid unnecessary copying for objects that span pages. Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* staging: zram/zcache: swtich Kconfig dependency from X86 to ZSMALLOCSeth Jennings2012-06-251-4/+1Star
| | | | | | | | | | This patch switches zcache and zram dependency to ZSMALLOC rather than X86. There is no net change since ZSMALLOC depends on X86, however, this prevent further changes to these files as zsmalloc dependencies change. Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* staging: zram: conventions, __aligned() attributeSam Hansen2012-06-111-1/+1
| | | | | | | Using the __aligned() attribute in favor of __attribute__((aligned(size))) Signed-off-by: Sam Hansen <solid.se7en@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* staging: zram: conventions pr_warning -> pr_warn()Sam Hansen2012-06-111-4/+4
| | | | | | | | Porting zram to use the pr_warn() function instead of the deprecated pr_warning(). Signed-off-by: Sam Hansen <solid.se7en@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* staging: zram: remove special handle of uncompressed pageMinchan Kim2012-06-113-112/+15Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xvmalloc can't handle PAGE_SIZE page so that zram have to handle it specially but zsmalloc can do it so let's remove unnecessary special handling code. Quote from Nitin "I think page vs handle distinction was added since xvmalloc could not handle full page allocation. Now that zsmalloc allows full page allocation, we can just use it for both cases. This would also allow removing the ZRAM_UNCOMPRESSED flag. The only downside will be slightly slower code path for full page allocation but this event is anyways supposed to be rare, so should be fine." 1. This patch reduces code very much. drivers/staging/zram/zram_drv.c | 104 +++++-------------------------------- drivers/staging/zram/zram_drv.h | 17 +----- drivers/staging/zram/zram_sysfs.c | 6 +-- 3 files changed, 15 insertions(+), 112 deletions(-) 2. change pages_expand with bad_compress so it can count bad compression(above 75%) ratio. 3. remove zobj_header which is for back-reference for defragmentation because firstly, it's not used at the moment and zsmalloc can't handle bigger size than PAGE_SIZE so zram can't do it any more without redesign. Cc: Seth Jennings <sjenning@linux.vnet.ibm.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* staging: zram: fix random data readMinchan Kim2012-06-111-7/+8
| | | | | | | | | | | | fd1a30de makes a bug that it uses (struct page *) as zsmalloc's handle although it's a uncompressed page so that it can access random page, return random data or even crashed by get_first_page in zs_map_object. Cc: Seth Jennings <sjenning@linux.vnet.ibm.com> Cc: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* staging: zsmalloc: zsmalloc: use unsigned long instead of void *Minchan Kim2012-06-112-9/+9
| | | | | | | | | | | | | | | | | | | | | | | | We should use unsigned long as handle instead of void * to avoid any confusion. Without this, users may just treat zs_malloc return value as a pointer and try to deference it. This patch passed compile test(zram, zcache and ramster) and zram is tested on qemu. changelog * from v2 - remove hval pointed out by Nitin - based on next-20120607 * from v1 - change zcache's zv_create return value - baesd on next-20120604 Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Minchan Kim <minchan@kernel.org> Acked-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge branch 'kmap_atomic' of git://github.com/congwang/linuxLinus Torvalds2012-03-211-16/+16
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kmap_atomic cleanup from Cong Wang. It's been in -next for a long time, and it gets rid of the (no longer used) second argument to k[un]map_atomic(). Fix up a few trivial conflicts in various drivers, and do an "evil merge" to catch some new uses that have come in since Cong's tree. * 'kmap_atomic' of git://github.com/congwang/linux: (59 commits) feature-removal-schedule.txt: schedule the deprecated form of kmap_atomic() for removal highmem: kill all __kmap_atomic() [swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename] drbd: remove the second argument of k[un]map_atomic() zcache: remove the second argument of k[un]map_atomic() gma500: remove the second argument of k[un]map_atomic() dm: remove the second argument of k[un]map_atomic() tomoyo: remove the second argument of k[un]map_atomic() sunrpc: remove the second argument of k[un]map_atomic() rds: remove the second argument of k[un]map_atomic() net: remove the second argument of k[un]map_atomic() mm: remove the second argument of k[un]map_atomic() lib: remove the second argument of k[un]map_atomic() power: remove the second argument of k[un]map_atomic() kdb: remove the second argument of k[un]map_atomic() udf: remove the second argument of k[un]map_atomic() ubifs: remove the second argument of k[un]map_atomic() squashfs: remove the second argument of k[un]map_atomic() reiserfs: remove the second argument of k[un]map_atomic() ocfs2: remove the second argument of k[un]map_atomic() ntfs: remove the second argument of k[un]map_atomic() ...
| * zram: remove the second argument of k[un]map_atomic()Cong Wang2012-03-202-42/+41Star
| | | | | | | | | | Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Cong Wang <amwang@redhat.com>
* | staging: zram: Rename module parameterNitin Gupta2012-02-143-13/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | zram accepts number of devices to be created as a module parameter. This was renamed from num_devices to zram_num_devices (without updating the documentation!) since num_devices was declared as a non-static global variable, polluting the global namespace. Now, we declare it as a static variable and revert back the name change. The documentation (zram.txt) already mentions num_devices as the module parameter name. Signed-off-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | staging: fix powerpc linux-next break on zsmallocSeth Jennings2012-02-131-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | linux/vmalloc.h added to zsmalloc-main.c to resolve implicit declaration errors. X86 dependency added to zsmalloc and dependent drivers zcache and zram. This X86 only requirement is not ideal. Working to find portable functions for __flush_tlb_one and set_pte. Signed-off-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | staging: zram: remove xvmallocNitin Gupta2012-02-093-635/+0Star
| | | | | | | | | | | | | | | | Removes the xvmalloc allocator code from the zram driver Signed-off-by: Nitin Gupta <ngupta@vflare.org> Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | staging: zram: replace xvmalloc with zsmallocNitin Gupta2012-02-095-62/+46Star
|/ | | | | | | | | Replaces xvmalloc with zsmalloc as the compressed page allocator for zram Signed-off-by: Nitin Gupta <ngupta@vflare.org> Acked-by: Seth Jennings <sjenning@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Staging: zram: Add a missing GFP_KERNEL specifier in zram_init_device()Jerome Marchand2011-12-081-1/+2
| | | | | | | | | | The allocation of zram->compress_buffer is misssing a GFP_* specifier. This is equivalent to GFP_NOWAIT but it is more likely a omission. Since the allocation just above it uses GFP_KERNEL, there is no reason to use GFP_NOWAIT here. Therefore, add GFP_KERNEL. Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Staging: zram/zram_sysfs.c: Fixed call of obsolete function strict_strtoXSergey Datsevich2011-12-081-3/+3
| | | | | | | | | As reported by checkpatch.pl strict_strtoX is obsolet and should be replaced by kstrtoX. Signed-off-by: Sergey Datsevich <srgdts@gmail.com> Signed-off-by: Bjoern Meier <bjoernmeier@hotmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Merge branch 'for-3.2/core' of git://git.kernel.dk/linux-blockLinus Torvalds2011-11-051-3/+2Star
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-3.2/core' of git://git.kernel.dk/linux-block: (29 commits) block: don't call blk_drain_queue() if elevator is not up blk-throttle: use queue_is_locked() instead of lockdep_is_held() blk-throttle: Take blkcg->lock while traversing blkcg->policy_list blk-throttle: Free up policy node associated with deleted rule block: warn if tag is greater than real_max_depth. block: make gendisk hold a reference to its queue blk-flush: move the queue kick into blk-flush: fix invalid BUG_ON in blk_insert_flush block: Remove the control of complete cpu from bio. block: fix a typo in the blk-cgroup.h file block: initialize the bounce pool if high memory may be added later block: fix request_queue lifetime handling by making blk_queue_cleanup() properly shutdown block: drop @tsk from attempt_plug_merge() and explain sync rules block: make get_request[_wait]() fail if queue is dead block: reorganize throtl_get_tg() and blk_throtl_bio() block: reorganize queue draining block: drop unnecessary blk_get/put_queue() in scsi_cmd_ioctl() and blk_get_tg() block: pass around REQ_* flags instead of broken down booleans during request alloc/free block: move blk_throtl prototypes to block/blk.h block: fix genhd refcounting in blkio_policy_parse_and_set() ... Fix up trivial conflicts due to "mddev_t" -> "struct mddev" conversion and making the request functions be of type "void" instead of "int" in - drivers/md/{faulty.c,linear.c,md.c,md.h,multipath.c,raid0.c,raid1.c,raid10.c,raid5.c} - drivers/staging/zram/zram_drv.c
| * block: remove support for bio remapping from ->make_requestChristoph Hellwig2011-09-121-5/+3Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is very little benefit in allowing to let a ->make_request instance update the bios device and sector and loop around it in __generic_make_request when we can archive the same through calling generic_make_request from the driver and letting the loop in generic_make_request handle it. Note that various drivers got the return value from ->make_request and returned non-zero values for errors. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
* | zram: Fix sparse warningsNitin Gupta2011-09-102-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | Fixes sparse warning: zram_drv.c:666:6: warning: symbol 'zram_slot_free_notify' was not declared. Should it be static? Also, max_zpage_size is now size_t just to be consistent with data-type of other variables maintaining sizes of various kinds. Signed-off-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | staging: zram: prevent accessing an unallocated table when init fails earlyJerome Marchand2011-09-071-5/+6
| | | | | | | | | | | | | | | | | | | | When the allocation of zram->table fails, we set zram->disksize to zero to prevent accessing the unallocated table entries during cleanup. However, we currently don't take this precaution when the initialization fails earlier. Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | staging: zram: fix zram lockingJerome Marchand2011-09-073-26/+44
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently init_lock only prevents concurrent execution of zram_init_device() and zram_reset_device() but not zram_make_request() nor sysfs store functions. This patch changes init_lock into a rw_semaphore. A write lock is taken by init, reset and store functions, a read lock is taken by zram_make_request(). Also, avoids to release the lock before calling __zram_reset_device() for cleaning after a failed init, thus preventing any concurrent task to see an inconsistent state of zram. Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | staging: zram: make global var "num_devices" use unique nameNoah Watkins2011-08-233-13/+13
| | | | | | | | | | | | | | | | The global variable "num_devices" is too general to be global. This patch switches the name to be "zram_num_devices". Signed-off-by: Noah Watkins <noahwatkins@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | staging: zram: make global var "devices" use unique nameNoah Watkins2011-08-233-10/+10
|/ | | | | | | | The global variable "devices" is too general to be global. This patch switches the name to be "zram_devices". Signed-off-by: Noah Watkins <noahwatkins@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Staging: zram: Fix kunmapping orderJerome Marchand2011-07-181-2/+2
| | | | | | | | | | | This patch fixes the unmapping order of KM_USER0/1 in handle_uncompressed_page() and zram_read() so that kmap()/kunmap() calls are correctly nested. Reported-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Reviewed-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Staging: zram: Replace mutex lock by a R/W semaphoreJerome Marchand2011-07-052-14/+15
| | | | | | | | | | | | | | | | | | | | | Currently, nothing protects zram table from concurrent access. For instance, ZRAM_UNCOMPRESSED bit can be cleared by zram_free_page() called from a concurrent write between the time ZRAM_UNCOMPRESSED has been set and the time it is tested to unmap KM_USER0 in zram_bvec_write(). This ultimately leads to kernel panic. Also, a read request can occurs when the page has been freed by a running write request and before it has been updated, leading to zero filled block being incorrectly read and "Read before write" error message. This patch replace the current mutex by a rw_semaphore. It extends the protection to zram table (currently, only compression buffers are protected) and read requests (currently, only write requests are protected). Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Staging: zram: allow partial page operationsJerome Marchand2011-07-052-38/+169
| | | | | | | | | | | | | | | | Commit 7b19b8d45b216ff3186f066b31937bdbde066f08 (zram: Prevent overflow in logical block size) introduced ZRAM_LOGICAL_BLOCK_SIZE constant to prevent overflow of logical block size on 64k page kernel. However, the current implementation of zram only allow operation on block of the same size as a page. That makes theorically legit 4k requests fail on 64k page kernel. This patch makes zram allow operation on partial pages. Basically, it means we still do operations on full pages internally, but only copy the relevent segments from/to the user memory. Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Staging: zram: Refactor zram_read/write() functionsJerome Marchand2011-07-051-160/+155Star
| | | | | | | | | | This patch refactor the code of zram_read/write() functions. It does not removes a lot of duplicate code alone, but is mostly a helper for the third patch of this series (Staging: zram: allow partial page operations). Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Staging: zram: Remove useless offset calculation in handle_uncompressed_page()Jerome Marchand2011-07-051-2/+1Star
| | | | | | | | The offset of uncompressed page is always zero: handle_uncompressed_page() doesn't have to care about it. Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* staging: Allow sharing xvmalloc for zram and zcacheNitin Gupta2011-02-233-1/+15
| | | | | | | | | | | | | | | Both zram and zcache use xvmalloc allocator. If xvmalloc is compiled separately for both of them, we will get linker error if they are both selected as "built-in". We can also get linker error regarding missing xvmalloc symbols if zram is not built. So, we now compile xvmalloc separately and export its symbols which are then used by both of zram and zcache. Signed-off-by: Nitin Gupta <ngupta@vflare.org> Acked-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Staging: zram: initialize device on first readJerome Marchand2011-02-181-12/+7Star
| | | | | | | | | | | | | | Currently the device is initialized when first write is done to the device. Any read attempt before the first write would fail, including "hidden" read the user may not know about (as for example if he tries to write a partial block). This patch initializes the device on first request, whether read or write. Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Cc: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Merge 2.6.38-rc5 into staging-nextGreg Kroah-Hartman2011-02-181-0/+4
|\ | | | | | | | | | | | | | | | | | | | | This is to resolve a merge conflict with: drivers/staging/zram/zram_drv.c as pointed out by Stephen Rothwell Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Robert Jennings <rcj@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| * staging: zram: fix data corruption issueNitin Gupta2011-02-091-0/+4
| | | | | | | | | | | | | | | | | | | | In zram_read() and zram_write() we were not incrementing the index number and thus were reading/writing values from/to incorrect sectors on zram disk, resulting in data corruption. Signed-off-by: Nitin Gupta <ngupta@vflare.org> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | zram/xvmalloc: combine duplicate block delete codeRobert Jennings2011-02-041-42/+31Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch eliminates duplicate code. The remove_block_head function is a special case of remove_block which can be contained in remove_block without confusion. The portion of code in remove_block_head which was noted as "DEBUG ONLY" is now mandatory. Doing this provides consistent management of the double linked list of blocks under a freelist and makes this consolidation of delete block code safe. The first and last blocks will have NULL pointers in their previous and next page pointers respectively. Additionally, any time a block is removed from a free list the next and previous pointers will be set to NULL to avoid misuse outside xvmalloc. Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Acked-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | zram: Return zero'd pages on new readsRobert Jennings2011-02-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently zram will do nothing to the page in the bvec when that page has not been previously written. This allows random data to leak to user space. That can be seen by doing the following: ## Load the module and create a 256Mb zram device called /dev/zram0 # modprobe zram # echo $((256*1024*1024)) > /sys/class/block/zram0/disksize ## Initialize the device by writing zero to the first block # dd if=/dev/zero of=/dev/zram0 bs=512 count=1 ## Read ~256Mb of memory into a file and hope for something interesting # dd if=/dev/zram0 of=file This patch will treat an unwritten page as a zero-filled page. If a page is read before a write has occurred the data returned is all 0's. Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | zram/xvmalloc: Close 32byte hole on 64bit CPUsRobert Jennings2011-02-041-5/+2Star
| | | | | | | | | | | | | | | | | | By swapping the total_pages statistic with the lock we close a hole in the structure for 64-bit CPUs. Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | zram/xvmalloc: create CONFIG_ZRAM_DEBUG for debug codeRobert Jennings2011-02-043-0/+16
| | | | | | | | | | | | | | | | | | Add a debug config flag to enable debug printk output and future debug code. Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | zram/xvmalloc: free bit block insertion optimizationRobert Jennings2011-02-041-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This change is in a conditional block which is entered only when there is an existing data block on the freelist where the insert has taken place. The new block is pushed onto the freelist stack and this conditional block is updating links in the prior stack head to point to the new stack head. After this conditional block the first-/second-level indices are updated to indicate that there is a free block at this location. This patch adds an immediate return from the conditional block to avoid setting bits again to indicate a free block on this freelist. The bits would already be set because there was an existing free block on this freelist. Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | zram: Prevent overflow in logical block sizeRobert Jennings2011-02-042-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | On a 64K page kernel, the value PAGE_SIZE passed to blk_queue_logical_block_size would overflow the logical block size argument (resulting in setting it to 0). This patch sets the logical block size to 4096, using a new ZRAM_LOGICAL_BLOCK_SIZE constant. Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | zram/vmalloc: Correct tunings to enable use with 64K pagesRobert Jennings2011-02-041-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xvmalloc will not currently function with 64K pages. Newly allocated pages will be inserted at an offset beyond the end of the first-level index. This tuning is needed to properly size the allocator for 64K pages. The default 3 byte shift results in a second level list size which can not be indexed using the 64 bits of the flbitmap in the xv_pool structure. The shift must increase to 4 bytes between second level list entries to fit the size of the first level bitmap. Here are a few statistics for structure sizes on 32- and 64-bit CPUs with 4KB and 64KB page sizes. bits_per_long 32 64 64 page_size 4,096 4,096 65,535 xv_align 4 8 8 fl_delta 3 3 4 num_free_lists 508 508 4,094 xv_pool size 4,144b 8,216b 66,040b per object overhead 32 64 64 zram struct 0.5GB disk 512KB 1024KB 64KB This patch maintains the current tunings for 4K pages, adds an optimal sizing for 64K pages and adds a safe tuning for any other page sizes. Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com> Reviewed-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* | Staging: zram: simplify zram_make_requestNitin Gupta2011-01-251-11/+8Star
| | | | | | | | | | | | | | | | | | | | zram_read() and zram_write() always return zero, so make them return void to simplify the code. Signed-off-by: Nitin Gupta <ngupta@vflare.org> Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-22 02:08:16 +0200