passt/iov.h, branch podman_25959 Plug A Simple Socket Transport iov: iov tail helpers 2024-11-28T13:03:16+00:00 David Gibson david@gibson.dropbear.id.au 2024-11-27T03:54:04+00:00 f9311031713ab8f18e9c872a42a8f6a9935954ec In the vhost-user code we have a number of places where we need to locate a particular header within the guest-supplied IO vector. We need to work out which buffer the header is in, and verify that it's contiguous and aligned as we need. At the moment this is open-coded, but introduce a helper to make this more straightforward. We add a new datatype 'struct iov_tail' representing an IO vector from which we've logically consumed some number of headers. The IOV_PULL_HEADER macro consumes a new header from the vector, returning a pointer and updating the iov_tail. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> 
In the vhost-user code we have a number of places where we need to locate
a particular header within the guest-supplied IO vector.  We need to work
out which buffer the header is in, and verify that it's contiguous and
aligned as we need.  At the moment this is open-coded, but introduce a
helper to make this more straightforward.

We add a new datatype 'struct iov_tail' representing an IO vector from
which we've logically consumed some number of headers.  The IOV_PULL_HEADER
macro consumes a new header from the vector, returning a pointer and
updating the iov_tail.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
iov: remove iov_copy() 2024-06-13T13:45:40+00:00 Laurent Vivier lvivier@redhat.com 2024-06-13T12:36:54+00:00 7290335b146c61495178c73310bc6727608988cc it was needed by a draft version of vhost-user, it is not needed anymore. Signed-off-by: Laurent Vivier <lvivier@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> 
it was needed by a draft version of vhost-user, it is not needed
anymore.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
iov: Helper macro to construct iovs covering existing variables or fields 2024-05-02T14:13:31+00:00 David Gibson david@gibson.dropbear.id.au 2024-05-01T06:53:52+00:00 35598995869b0966eb97a16411d6ba5053005431 Laurent's recent changes mean we use IO vectors much more heavily in the TCP code. In many of those cases, and few others around the code base, individual iovs of these vectors are constructed to exactly cover existing variables or fields. We can make initializing such iovs shorter and clearer with a macro for the purpose. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> 
Laurent's recent changes mean we use IO vectors much more heavily in the
TCP code.  In many of those cases, and few others around the code base,
individual iovs of these vectors are constructed to exactly cover existing
variables or fields.  We can make initializing such iovs shorter and
clearer with a macro for the purpose.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
iov: Improve documentation of iov_skip_bytes() 2024-03-07T22:09:15+00:00 David Gibson david@gibson.dropbear.id.au 2024-03-01T04:06:44+00:00 137ce017896b2b64f8c45a8ddefbaed2cb71c445 As pointed out in review, the documentation comments for iov_skip_bytes() are more confusing than they should be. Reword them, including updating parameter names, to make it clearer. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> 
As pointed out in review, the documentation comments for iov_skip_bytes()
are more confusing than they should be.  Reword them, including updating
parameter names, to make it clearer.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
iov: Add helper to find skip over first n bytes of an io vector 2024-02-29T05:24:07+00:00 David Gibson david@gibson.dropbear.id.au 2024-02-28T01:52:01+00:00 64b63d9e3e1dc2e4c1f32432cf8954f6cc3f788f Several of the IOV functions in iov.c, and also tap_send_frames_passt() needs to determine which buffer element a byte offset into an IO vector lies in. Split this out into a helper function iov_skip_bytes(). Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> 
Several of the IOV functions in iov.c, and also tap_send_frames_passt()
needs to determine which buffer element a byte offset into an IO vector
lies in.  Split this out into a helper function iov_skip_bytes().

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
iov: add some functions to manage iovec 2024-02-29T05:23:49+00:00 Laurent Vivier lvivier@redhat.com 2024-02-28T01:52:00+00:00 2a6f8bcca77ae7391a8943a3791be2fbb98a918b Introduce functions to copy to/from a buffer from/to an iovec array, to compute data length in in bytes of an iovec and to copy memory from an iovec to another. iov_from_buf(), iov_to_buf(), iov_size(), iov_copy(). Signed-off-by: Laurent Vivier <lvivier@redhat.com> Message-ID: <20240217150725.661467-2-lvivier@redhat.com> [dwg: Small changes to suppress cppcheck warnings] Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> 
Introduce functions to copy to/from a buffer from/to an iovec array,
to compute data length in in bytes of an iovec and to copy memory from
an iovec to another.

iov_from_buf(), iov_to_buf(), iov_size(), iov_copy().

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-ID: <20240217150725.661467-2-lvivier@redhat.com>
[dwg: Small changes to suppress cppcheck warnings]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>