feat: add InstancePolicy.reservation field for restricting jobs to a …

…specific reservation

---
docs: elaborate the usage of Container.volumes proto field
PiperOrigin-RevId: 570165566

google/cloud/batch/v1/job.proto

@@ -268,6 +268,7 @@ message AllocationPolicy {
       // * `batch-centos`: use Batch CentOS images.
       // * `batch-cos`: use Batch Container-Optimized images.
       // * `batch-hpc-centos`: use Batch HPC CentOS images.
+      // * `batch-hpc-rocky`: use Batch HPC Rocky Linux images.
       string image = 4;
 
       // Name of a snapshot used as the data source.
@@ -377,6 +378,10 @@ message AllocationPolicy {
     // file system or a raw storage drive that is not ready for data
     // storage and accessing.
     repeated AttachedDisk disks = 6;
+
+    // Optional. If specified, VMs will consume only the specified reservation.
+    // If not specified (default), VMs will consume any applicable reservation.
+    string reservation = 7 [(google.api.field_behavior) = OPTIONAL];
   }
 
   // InstancePolicyOrTemplate lets you define the type of resources to use for

google/cloud/batch/v1/task.proto

@@ -159,6 +159,14 @@ message Runnable {
     // Volumes to mount (bind mount) from the host machine files or directories
     // into the container, formatted to match docker run's --volume option,
     // e.g. /foo:/bar, or /foo:/bar:ro
+    //
+    // If the `TaskSpec.Volumes` field is specified but this field is not, Batch
+    // will mount each volume from the host machine to the container with the
+    // same mount path by default. In this case, the default mount option for
+    // containers will be read-only (ro) for existing persistent disks and
+    // read-write (rw) for other volume types, regardless of the original mount
+    // options specified in `TaskSpec.Volumes`. If you need different mount
+    // settings, you can explicitly configure them in this field.
     repeated string volumes = 7;
 
     // Arbitrary additional options to include in the "docker run" command when