Merge tag 'migration-20230215-pull-request' of https://gitlab.com/juan.quintela/qemu into staging

Migration Pull request

This pull request contains:

* Add qemu_file_get_to_fd() a.k.a. make vfio happy(Avihai)
* migration/block is now DPRINTF() free zone (Philippe)
* remove res_compat and improve docs (me)

Please apply.

# -----BEGIN PGP SIGNATURE-----
#
# iQIzBAABCAAdFiEEGJn/jt6/WMzuA0uC9IfvGFhy1yMFAmPtOxgACgkQ9IfvGFhy
# 1yM+8w/+Nrm40o8B+0M1X/2O8SPaXE0Oxll5qk5AgfC+2Ef/n5661ZzOM1xQcqzv
# CN3bj3g7dKN05nGhqW5ZFrEZliJCGksx2FBKMq9H6R5YBSMo/+GHT4ugPqsujudl
# RBafIHzp4h4nTh/4aJ4Kr2Vn/bVQzGVyv5c6yUdUhKhE1QfCLu9AMC5vN1hfWxBz
# IQBvMkLNXXhWOTdkVAElVlFOM6GZzWb1UYDkBaQHjjw/dN0MdCFFj7tIaBIyU2Eb
# KyQCoYeJjjWrljsrfzfCucrW+mbVGmCe1TiCEnaAmmgzOI0NwARmUcdYdCyZ4Nhh
# flNjpqQB6H4/ekI0mus2YPMPEkHyVgBMuF8fHV3YDwxcQ25U39RLymVfAoKPNg88
# S1EcQ9h2QVqdML7bR9vTmPOZKk5vD25H7B8LQIJpT8PHVg3ZzzRaOIR8UHmmFXx/
# PSL1rGfPcCLJ3P1XlVjwBApebMHyid9c+Sohda9L9HPer0jlB+mGQUEV8J67DJiT
# xlffFgJmYu3+AJu9BoqrG0AUW6zA78jSs4Tbp78qbIVA4uzGkWI9JvROMfG9Qcc7
# vruuL0sUXHVUhzW2F+0M+b1rVhaHHQYvFo3mIqdHrd5mGicdgh1HUbaJuEJxeJnh
# oFt6SZbIx3N/pllcvMsxQa+rFI/po+FEkRwIF02SzTRWYHB0qos=
# =KpKO
# -----END PGP SIGNATURE-----
# gpg: Signature made Wed 15 Feb 2023 20:05:44 GMT
# gpg:                using RSA key 1899FF8EDEBF58CCEE034B82F487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>" [full]
# gpg:                 aka "Juan Quintela <quintela@trasno.org>" [full]
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* tag 'migration-20230215-pull-request' of https://gitlab.com/juan.quintela/qemu:
  migration: Rename res_{postcopy,precopy}_only
  migration: Remove unused res_compatible
  migration: In case of postcopy, the memory ends in res_postcopy_only
  migration/block: Convert remaining DPRINTF() debug macro to trace events
  migration/qemu-file: Add qemu_file_get_to_fd()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 34 insertions, 0 deletions

diff --git a/migration/qemu-file.c b/migration/qemu-file.c
index 2d5f74ffc2..102ab3b439 100644
--- a/migration/qemu-file.c
+++ b/migration/qemu-file.c
@@ -940,3 +940,37 @@ QIOChannel *qemu_file_get_ioc(QEMUFile *file)
 {
     return file->ioc;
 }
+
+/*
+ * Read size bytes from QEMUFile f and write them to fd.
+ */
+int qemu_file_get_to_fd(QEMUFile *f, int fd, size_t size)
+{
+    while (size) {
+        size_t pending = f->buf_size - f->buf_index;
+        ssize_t rc;
+
+        if (!pending) {
+            rc = qemu_fill_buffer(f);
+            if (rc < 0) {
+                return rc;
+            }
+            if (rc == 0) {
+                return -EIO;
+            }
+            continue;
+        }
+
+        rc = write(fd, f->buf + f->buf_index, MIN(pending, size));
+        if (rc < 0) {
+            return -errno;
+        }
+        if (rc == 0) {
+            return -EIO;
+        }
+        f->buf_index += rc;
+        size -= rc;
+    }
+
+    return 0;
+}