use std::cmp::max;
use std::cmp::min;
use std::fs::File;
use std::fs::OpenOptions;
use std::os::fd::AsRawFd;
use anyhow::Context;
use base::add_fd_flags;
use base::flock;
use base::open_file_or_duplicate;
use base::unix::iov_max;
use base::FlockOperation;
use cros_async::Executor;
use disk::DiskFile;
use crate::virtio::block::DiskOption;
use crate::virtio::BlockAsync;
pub fn get_seg_max(queue_size: u16) -> u32 {
let seg_max = min(max(iov_max(), 1), u32::max_value() as usize) as u32;
min(seg_max, u32::from(queue_size) - 2)
}
impl DiskOption {
pub fn open(&self) -> anyhow::Result<Box<dyn DiskFile>> {
let mut options = OpenOptions::new();
options.read(true).write(!self.read_only);
let raw_image: File = open_file_or_duplicate(&self.path, &options)
.with_context(|| format!("failed to load disk image {}", self.path.display()))?;
let lock_op = if self.read_only {
FlockOperation::LockShared
} else {
FlockOperation::LockExclusive
};
flock(&raw_image, lock_op, true)
.with_context(|| format!("failed to lock disk image {}", self.path.display()))?;
if self.direct {
add_fd_flags(raw_image.as_raw_fd(), libc::O_DIRECT)
.with_context(|| format!("failed to set O_DIRECT to {}", &self.path.display()))?;
}
disk::create_disk_file(raw_image, self.sparse, disk::MAX_NESTING_DEPTH, &self.path)
.context("create_disk_file failed")
}
}
impl BlockAsync {
pub fn create_executor(&self) -> Executor {
Executor::with_executor_kind(self.executor_kind).expect("Failed to create an executor")
}
}