Allow setting journal size and tag size for integrity metadata pre-allocations on create

[mulkieran]

No description provided.

[mulkieran]

Current pool create help text:

usage: stratis pool create [-h] [--clevis {nbde,tang,tpm2}]
                           [--tang-url TANG_URL]
                           [--trust-url | --thumbprint THUMBPRINT]
                           [--journal-size JOURNAL_SIZE] [--tag-size TAG_SIZE]
                           [--key-desc KEY_DESC] [--no-overprovision]
                           pool_name blockdevs [blockdevs ...]

positional arguments:
  pool_name             Name of new pool
  blockdevs             Create the pool using these block devs

options:
  -h, --help            show this help message and exit
  --key-desc KEY_DESC   Key description of key in kernel keyring to use for
                        encryption
  --no-overprovision    Do not allow the sum of the logical size of the pool's
                        filesystems to exceed the size of the pool's data
                        area.

clevis:
  Arguments controlling creation with Clevis encryption

  --clevis {nbde,tang,tpm2}
                        Specification for binding with Clevis.
  --tang-url TANG_URL   URL of Clevis tang server (--clevis=[tang|nbde] must
                        be set)
  --trust-url           Omit verification of tang server credentials (--tang-
                        url option must be set)
  --thumbprint THUMBPRINT
                        Thumbprint of tang server (--tang-url option must be
                        set)

integrity:
  Optional parameters for configuring integrity metadata pre-allocation

  --journal-size JOURNAL_SIZE
                        Size of integrity device's journal. Each block is
                        written to this journal before being written to its
                        address. The size of must be a multiple of 4 KiB.
  --tag-size TAG_SIZE   Size of tag to use to verify correctness of 4KiB
                        block, e.g, 64B. Must be a power of 2 and less than
                        128B.

We could call the two newly added options, --integrity-journal-size and --integrity-tag-size.

[mulkieran]

man pages not yet written.

[mulkieran]

New help text:

$ PYTHONPATH=./src ./bin/stratis pool create --help
usage: stratis pool create [-h] [--clevis {nbde,tang,tpm2}]
                           [--tang-url TANG_URL]
                           [--trust-url | --thumbprint THUMBPRINT]
                           [--journal-size JOURNAL_SIZE]
                           [--tag-spec {0b,32b,512b}] [--key-desc KEY_DESC]
                           [--no-overprovision]
                           pool_name blockdevs [blockdevs ...]

positional arguments:
  pool_name             Name of new pool
  blockdevs             Create the pool using these block devs

options:
  -h, --help            show this help message and exit
  --key-desc KEY_DESC   Key description of key in kernel keyring to use for
                        encryption
  --no-overprovision    Do not allow the sum of the logical size of the pool's
                        filesystems to exceed the size of the pool's data
                        area.

clevis:
  Arguments controlling creation with Clevis encryption

  --clevis {nbde,tang,tpm2}
                        Specification for binding with Clevis.
  --tang-url TANG_URL   URL of Clevis tang server (--clevis=[tang|nbde] must
                        be set)
  --trust-url           Omit verification of tang server credentials (--tang-
                        url option must be set)
  --thumbprint THUMBPRINT
                        Thumbprint of tang server (--tang-url option must be
                        set)

integrity:
  Optional parameters for configuring integrity metadata pre-allocation

  --journal-size JOURNAL_SIZE
                        Size of integrity device's journal. Each block is
                        written to this journal before being written to its
                        address. The size of the journal must be a multiple of
                        4 KiB.
  --tag-spec {0b,32b,512b}
                        Integrity tag specification defining the size of the
                        tag used to store a checksum or other value for each
                        block on a device. stratisd chooses a default
                        specification if none is given.

[mulkieran]

squashed

[drckeefe]

Some information about what the defaults might be and would the choices be in bytes or bits could help users.

[mulkieran]

Revised help text:

integrity:
  Optional parameters for configuring integrity metadata pre-allocation

  --journal-size JOURNAL_SIZE
                        Size of integrity device's journal. Each block is
                        written to this journal before being written to its
                        address. The default is 128 MiB. Specify 0B if you
                        have determined that you will never make use of
                        integrity features.
  --tag-spec {0b,32b,512b}
                        Integrity tag specification defining the size of the
                        tag used to store a checksum or other value for each
                        block on a device. All size specifications are in
                        bits. The default is 512b. Specify 0b if you have
                        determined that you will never make use of integrity
                        features.

stratis will implement these defaults. At present they coincide with the stratisd defaults.

[mulkieran]

Or...

integrity:
  Optional parameters for configuring integrity metadata pre-allocation

  --integrity {no, pre-allocate, yes}                   # yes will not be available in the CLI yet
        no if this pool will never make use of integrity features.
        pre-allocate if this pool should pre-allocate space so that
        integrity features can be turned on later. The default is
        pre-allocate.

  --journal-size JOURNAL_SIZE
                        Size of integrity device's journal. Each block is
                        written to this journal before being written to its
                        address. The default is 128 MiB.

  --tag-spec {32b,512b}
                        Integrity tag specification defining the size of the
                        tag used to store a checksum or other value for each
                        block on a device. All size specifications are in
                        bits. The default is 512b.

If --integrity is set to "no" the two other options will be rejected if set by the user. If to pre-allocate, they are still optional.

In future, we can use the same options for "yes" as we do for pre-allocate.

[mulkieran]

New look is:

integrity:
  Optional parameters for configuring integrity metadata pre-allocation

  --integrity {no,pre-allocate}
                        Integrity options for this pool. If "no" no space will
                        be allocated for integrity metadata and it will never
                        be possible to turn on integrity functionality for
                        this pool. If "pre-allocate" then space will be
                        allocated for integrity metadata and it will be
                        possible to switch on integrity functionality in
                        future. The default is "pre-allocate".
  --journal-size JOURNAL_SIZE
                        Size of integrity device's journal. Each block is
                        written to this journal before being written to its
                        address. The default is 128 MiB.
  --tag-spec {32b,512b}
                        Integrity tag specification defining the size of the
                        tag used to store a checksum or other value for each
                        block on a device. All size specifications are in
                        bits. The default is 512b.