From f26f66d866ba1a9f3204e6fdfe2b07e67b5492ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 10 Apr 2024 21:41:32 +0200 Subject: Adding upstream version 2.8. Signed-off-by: Daniel Baumann --- Documentation/nvme-read.txt | 158 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 158 insertions(+) create mode 100644 Documentation/nvme-read.txt (limited to 'Documentation/nvme-read.txt') diff --git a/Documentation/nvme-read.txt b/Documentation/nvme-read.txt new file mode 100644 index 0000000..cecaa71 --- /dev/null +++ b/Documentation/nvme-read.txt @@ -0,0 +1,158 @@ +nvme-read(1) +============ + +NAME +---- +nvme-read - Send an NVMe Read command, provide results + +SYNOPSIS +-------- +[verse] +'nvme-read' [--start-block= | -s ] + [--block-count= | -c ] + [--data-size= | -z ] + [--metadata-size= | -y ] + [--ref-tag= | -r ] + [--data= | -d ] + [--metadata= | -M ] + [--prinfo= | -p ] + [--app-tag-mask= | -m ] + [--app-tag= | -a ] + [--limited-retry | -l] [--force-unit-access | -f] + [--dir-type= | -T ] + [--dir-spec= | -S ] [--dsm= | -D ] + [--show-command | -V] [--dry-run | -w] [--latency | -t] + [--storage-tag | -g ] + [--storage-tag-check | -C] [--force] + [--output-format= | -o ] [--verbose | -v] + +DESCRIPTION +----------- +The Read command reads the logical blocks specified by the command from +the medium and copies to the data data buffer provided. Will use stdout +by default if you don't provide a file. + +OPTIONS +------- +-s :: +--start-block=:: + Start block. + +-c:: +--block-count:: + The number of blocks to transfer. This is a zeroes based value to + align with the kernel's use of this field. (ie. 0 means transfer + 1 block). + +-z :: +--data-size=:: + Size of data, in bytes. + +-y :: +--metadata-size=:: + Size of metadata in bytes. + +-d :: +--data=:: + Data file. If none provided, contents are sent to STDOUT. + +-M :: +--metadata=:: + Metadata file, if necessary. + +-p :: +--prinfo=:: + Protection Information field definition. ++ +[] +|================= +|Bit|Description +|3|PRACT: Protection Information Action. When set to 1, PI is stripped/inserted +on read/write when the block format's metadata size is 8. When set to 0, +metadata is passes. +|2:0|PRCHK: Protection Information Check: +|2|Set to 1 enables checking the guard tag +|1|Set to 1 enables checking the application tag +|0|Set to 1 enables checking the reference tag +|================= + +-r :: +--ref-tag=:: + Optional reftag when used with protection information. + +-m :: +--app-tag-mask=:: + Optional application tag mask when used with protection information. + +-f:: +--force-unit-access:: + Set the force-unit access flag. + +-T :: +--dir-type=:: + Optional directive type. The nvme-cli only enforces the value + be in the defined range for the directive type, though the NVMe + specification (1.3a) defines only one directive, 01h, for write + stream identifiers. + +-S :: +--dir-spec=:: + Optional field for directive specifics. When used with + write streams, this value is defined to be the write stream + identifier. The nvme-cli will not validate the stream requested + is within the controller's capabilities. + +-D :: +--dsm=:: + The optional data set management attributes for this command. The argument + for this is the least significant 8 bits of the DSM field in a write + command; the most significant 16 bits of the field come from the directive + specific field, if used. This may be used to set attributes for + the LBAs being written, like access frequency, type, latency, + among other things, as well as yet to be defined types. Please + consult the NVMe specification for detailed breakdown of how to + use this field. + +-V:: +--show-cmd:: + Print out the command to be sent. + +-w:: +--dry-run:: + Do not actually send the command. If want to use --dry-run option, + --show-cmd option _must_ be set. Otherwise --dry-run option will be + _ignored_. + +-t:: +--latency:: + Print out the latency the IOCTL took (in us). + +-g :: +--storage-tag=:: + Variable Sized Expected Logical Block Storage Tag(ELBST). + +-C:: +--storage-tag-check:: + This flag enables Storage Tag field checking as part of end-to-end + data protection processing. + +--force:: + Ignore namespace is currently busy and performed the operation + even though. + +-o :: +--output-format=:: + Set the reporting format to 'normal', 'json' or 'binary'. Only one + output format can be used at a time. + +-v:: +--verbose:: + Increase the information detail in the output. + +EXAMPLES +-------- +No examples yet. + +NVME +---- +Part of the nvme-user suite -- cgit v1.2.3