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* dm cache: add block sizes and total cache blocks to status outputMike Snitzer2018-01-021-22/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | Improve cache_status to emit: <metadata block size> <#used metadata blocks>/<#total metadata blocks> <cache block size> <#used cache blocks>/<#total cache blocks> ... Adding the block sizes allows for easier calculation of the overall size of both the metadata and cache devices. Adding <#total cache blocks> provides useful context for how much of the cache is used. Unfortunately these additions to the status will require updates to users' scripts that monitor the cache status. But these changes help provide more comprehensive information about the cache device and will simplify tools that are being developed to manage dm-cache devices -- because they won't need to issue 3 operations to cobble together the information that we can easily provide via a single status ioctl. While updating the status documentation in cache.txt spaces were tabify'd. Requested-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Joe Maples <joe@frap129.org>
* CHROMIUM: dm: boot time specification of dm=Will Drewry2017-12-271-0/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a wrap-up of three patches pending upstream approval. I'm bundling them because they are interdependent, and it'll be easier to drop it on rebase later. 1. dm: allow a dm-fs-style device to be shared via dm-ioctl Integrates feedback from Alisdair, Mike, and Kiyoshi. Two main changes occur here: - One function is added which allows for a programmatically created mapped device to be inserted into the dm-ioctl hash table. This binds the device to a name and, optional, uuid which is needed by udev and allows for userspace management of the mapped device. - dm_table_complete() was extended to handle all of the final functional changes required for the table to be operational once called. 2. init: boot to device-mapper targets without an initr* Add a dm= kernel parameter modeled after the md= parameter from do_mounts_md. It allows for device-mapper targets to be configured at boot time for use early in the boot process (as the root device or otherwise). It also replaces /dev/XXX calls with major:minor opportunistically. The format is dm="name uuid ro,table line 1,table line 2,...". The parser expects the comma to be safe to use as a newline substitute but, otherwise, uses the normal separator of space. Some attempt has been made to make it forgiving of additional spaces (using skip_spaces()). A mapped device created during boot will be assigned a minor of 0 and may be access via /dev/dm-0. An example dm-linear root with no uuid may look like: root=/dev/dm-0 dm="lroot none ro, 0 4096 linear /dev/ubdb 0, 4096 4096 linear /dv/ubdc 0" Once udev is started, /dev/dm-0 will become /dev/mapper/lroot. Older upstream threads: http://marc.info/?l=dm-devel&m=127429492521964&w=2 http://marc.info/?l=dm-devel&m=127429499422096&w=2 http://marc.info/?l=dm-devel&m=127429493922000&w=2 Latest upstream threads: https://patchwork.kernel.org/patch/104859/ https://patchwork.kernel.org/patch/104860/ https://patchwork.kernel.org/patch/104861/ BUG: 27175947 Signed-off-by: Will Drewry <wad@chromium.org> Review URL: http://codereview.chromium.org/2020011 Change-Id: I92bd53432a11241228d2e5ac89a3b20d19b05a31
* dm verity: add ignore_zero_blocks featureSami Tolvanen2017-12-271-0/+5
| | | | | | | | | | | If ignore_zero_blocks is enabled dm-verity will return zeroes for blocks matching a zero hash without validating the content. Bug: 21893453 Change-Id: Ib9552f872bd82b1ba6a090686d2934a9551a3b48 Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> (cherry picked from commit 0b7462a60aad0c0819a138608c43998f3c46d6a8)
* dm verity: add support for forward error correctionSami Tolvanen2017-12-271-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | Add support for correcting corrupted blocks using Reed-Solomon. This code uses RS(255, N) interleaved across data and hash blocks. Each error-correcting block covers N bytes evenly distributed across the combined total data, so that each byte is a maximum distance away from the others. This makes it possible to recover from several consecutive corrupted blocks with relatively small space overhead. In addition, using verity hashes to locate erasures nearly doubles the effectiveness of error correction. Being able to detect corrupted blocks also improves performance, because only corrupted blocks need to corrected. For a 2 GiB partition, RS(255, 253) (two parity bytes for each 253-byte block) can correct up to 16 MiB of consecutive corrupted blocks if erasures can be located, and 8 MiB if they cannot, with 16 MiB space overhead. Bug: 21893453 Change-Id: Ib0372f49f45127e33bfe6b7182b0d608f56f3c7e Signed-off-by: Sami Tolvanen <samitolvanen@google.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> (cherry picked from commit a431c56bf1764448c12fd2d545b15466d552460c)
* dm verity: port upstream changes to 3.10Sami Tolvanen2017-12-271-9/+16
| | | | | | | | | | Upstream dm-verity has different optional parameters. Port back the relevant changes. Bug: 21893453 Change-Id: I5431388e041d6829ad60d2c86dd113210ba6aff7 Signed-off-by: Sami Tolvanen <samitolvanen@google.com> (cherry picked from commit 82cdd95a61c921c3c3063178c272b251573b596f)
* dm-verity: Add modes and emit uevent on corrupted blocksSami Tolvanen2017-12-271-1/+11
| | | | | | | | | | | | | | | | | | | | | | | Add a device specific mode to dm-verity for handling corrupted blocks: DM_VERITY_MODE_EIO is the default behavior, where reading a corrupted block results in -EIO. DM_VERITY_MODE_LOGGING only logs corrupted blocks, but does not block the read. DM_VERITY_MODE_RESTART calls kernel_restart when a corrupted block is discovered. Each mode sends a uevent to notify userspace of corruption and allow further recovery actions. Defaults to previous behavior, other modes can be enabled with an optional parameter added to the verity table. Change-Id: Ib72ae6ccb865594d28f3553bdcc5a40b1d7af390 Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
* first commitMeizu OpenSource2016-08-1519-0/+2017