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2013-11-07block: vhdx - add log write supportJeff Cody
This adds support for writing to the VHDX log. For spec details, see VHDX Specification Format v1.00: https://www.microsoft.com/en-us/download/details.aspx?id=34750 There are a few limitations to this log support: 1.) There is no caching yet 2.) The log is flushed after each entry The primary write interface, vhdx_log_write_and_flush(), performs a log write followed by an immediate flush of the log. As each log entry sector is a minimum of 4KB, partial sector writes are filled in with data from the disk write destination. If the current file log GUID is 0, a new GUID is generated and updated in the header. Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-07block: vhdx - add region overlap detection for image filesJeff Cody
Regions in the image file cannot overlap - the log, region tables, and metdata must all be unique and non-overlapping. This adds region checking by means of a QLIST; there can be a variable number of regions and metadata (there may be metadata or region tables that we do not recognize / know about, but are not required). This adds the capability to register a region for later checking, and to check against registered regions for any overlap. Also, if neither the BAT or Metadata region tables are found, return error. Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-07block: vhdx - log parsing, replay, and flush supportJeff Cody
This adds support for VHDX v0 logs, as specified in Microsoft's VHDX Specification Format v1.00: https://www.microsoft.com/en-us/download/details.aspx?id=34750 The following support is added: * Log parsing, and validation - validate that an existing log is correct. * Log search - search through an existing log, to find any valid sequence of entries. * Log replay and flush - replay an existing log, and flush/clear the log when complete. The VHDX log is a circular buffer, with elements (sectors) of 4KB. A log entry is a variably-length number of sectors, that is comprised of a header and 'descriptors', that describe each sector. A log may contain multiple entries, know as a log sequence. In a log sequence, each log entry immediately follows the previous entry, with an incrementing sequence number. There can only ever be one active and valid sequence in the log. Each log entry must match the file log GUID in order to be valid (along with other criteria). Once we have flushed all valid log entries, we marked the file log GUID to be zero, which indicates a buffer with no valid entries. Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-07block: vhdx - update log guid in header, and first write trackerJeff Cody
Allow tracking of first file write in the VHDX image, as well as the ability to update the GUID in the header. This is in preparation for log support. Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-07block: vhdx - break endian translation functions outJeff Cody
This moves the endian translation functions out from the vhdx.c source, into a separate source file. In addition to the previously defined endian functions, new endian translation functions for log support are added as well. Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-07block: vhdx - log support struct and definesJeff Cody
This adds some magic number defines, and internal structure definitions for VHDX log replay support. The struct VHDXLogEntries does not reflect an on-disk data structure, and thus does not need to be packed. Some minor code style fixes are applied as well. Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-07block: vhdx code movement - VHDXMetadataEntries and BDRVVHDXState to header.Jeff Cody
In preparation for VHDX log support, move these structures to the header. Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-07block: vhdx - add header update capability.Jeff Cody
This adds the ability to update the headers in a VHDX image, including generating a new MS-compatible GUID. As VHDX depends on uuid.h, VHDX is now a configurable build option. If VHDX support is enabled, that will also enable uuid as well. The default is to have VHDX enabled. To enable/disable VHDX: --enable-vhdx, --disable-vhdx Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-07block: vhdx - minor comments and typo correction.Jeff Cody
Just a couple of minor comments to help note where allocated buffers are freed, and a typo fix. Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-27misc: Fix new typos in comments and stringsStefan Weil
All these typos were found by codespell. sould -> should emperical -> empirical intialization -> initialization successfuly -> successfully gaurantee -> guarantee Fix also another error (before before) in the same context. Signed-off-by: Stefan Weil <sw@weilnetz.de> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-05-03block: initial VHDX driver support framework - supports open and probeJeff Cody
This is the initial block driver framework for VHDX image support (i.e. Hyper-V image file formats), that supports opening VHDX files, and parsing the headers. This commit does not yet enable: - reading - writing - updating the header - differencing files (images with parents) - log replay / dirty logs (only clean images) This is based on Microsoft's VHDX specification: "VHDX Format Specification v0.95", published 4/12/2012 https://www.microsoft.com/en-us/download/details.aspx?id=29681 Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-05-03block: vhdx header for the QEMU support of VHDX imagesJeff Cody
This is based on Microsoft's VHDX specification: "VHDX Format Specification v0.95", published 4/12/2012 https://www.microsoft.com/en-us/download/details.aspx?id=29681 These structures define the various header, metadata, and other block structures defined in the VHDX specification. Signed-off-by: Jeff Cody <jcody@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>