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|
extern "C" {
pub static stdout: *mut libc::FILE;
}
use getset::{CopyGetters, Getters};
use std::path::PathBuf;
#[derive(Getters, CopyGetters)]
pub struct FileSystem {
/// External UUID of the bcachefs
#[getset(get = "pub")]
uuid: uuid::Uuid,
/// Whether filesystem is encrypted
#[getset(get_copy = "pub")]
encrypted: bool,
/// Super block
#[getset(get = "pub")]
sb: bcachefs::bch_sb_handle,
/// Member devices for this filesystem
#[getset(get = "pub")]
devices: Vec<PathBuf>,
}
/// Parse a comma-separated mount options and split out mountflags and filesystem
/// specific options.
fn parse_mount_options(options: impl AsRef<str>) -> (Option<String>, u64) {
use either::Either::*;
let (opts, flags) = options
.as_ref()
.split(",")
.map(|o| match o {
"dirsync" => Left(libc::MS_DIRSYNC),
"lazytime" => Left(1 << 25), // MS_LAZYTIME
"mand" => Left(libc::MS_MANDLOCK),
"noatime" => Left(libc::MS_NOATIME),
"nodev" => Left(libc::MS_NODEV),
"nodiratime" => Left(libc::MS_NODIRATIME),
"noexec" => Left(libc::MS_NOEXEC),
"nosuid" => Left(libc::MS_NOSUID),
"ro" => Left(libc::MS_RDONLY),
"rw" => Left(0),
"relatime" => Left(libc::MS_RELATIME),
"strictatime" => Left(libc::MS_STRICTATIME),
"sync" => Left(libc::MS_SYNCHRONOUS),
"" => Left(0),
o @ _ => Right(o),
})
.fold((Vec::new(), 0), |(mut opts, flags), next| match next {
Left(f) => (opts, flags | f),
Right(o) => {
opts.push(o);
(opts, flags)
}
});
use itertools::Itertools;
(
if opts.len() == 0 {
None
} else {
Some(opts.iter().join(","))
},
flags,
)
}
impl FileSystem {
pub(crate) fn new(sb: bcachefs::bch_sb_handle) -> Self {
Self {
uuid: sb.sb().uuid(),
encrypted: sb.sb().crypt().is_some(),
sb: sb,
devices: vec![],
}
}
pub fn mount(
&self,
target: impl AsRef<std::path::Path>,
options: impl AsRef<str>,
) -> anyhow::Result<()> {
use itertools::Itertools;
use std::ffi::c_void;
use std::os::raw::c_char;
use std::os::unix::ffi::OsStrExt;
let src = self.devices.iter().map(|d| d.display()).join(":");
let (data, mountflags) = parse_mount_options(options);
let fstype = c_str!("bcachefs");
let src = std::ffi::CString::new(src)?; // bind the CString to keep it alive
let target = std::ffi::CString::new(target.as_ref().as_os_str().as_bytes())?; // ditto
let data = data.map(|data| std::ffi::CString::new(data)).transpose()?; // ditto
let src = src.as_c_str().to_bytes_with_nul().as_ptr() as *const c_char;
let target = target.as_c_str().to_bytes_with_nul().as_ptr() as *const c_char;
let data = data.as_ref().map_or(std::ptr::null(), |data| {
data.as_c_str().to_bytes_with_nul().as_ptr() as *const c_void
});
let ret = unsafe { libc::mount(src, target, fstype, mountflags, data) };
if ret == 0 {
Ok(())
} else {
Err(crate::ErrnoError(errno::errno()).into())
}
}
}
use crate::bcachefs;
use std::collections::HashMap;
use uuid::Uuid;
pub fn probe_filesystems() -> anyhow::Result<HashMap<Uuid, FileSystem>> {
use std::os::unix::ffi::OsStrExt;
let mut udev = udev::Enumerator::new()?;
let mut fss = HashMap::new();
udev.match_subsystem("block")?;
{
// Stop libbcachefs from spamming the output
let _gag = gag::Gag::stdout().unwrap();
for dev in udev.scan_devices()? {
if let Some(p) = dev.devnode() {
let path =
std::ffi::CString::new(p.as_os_str().as_bytes()).unwrap();
let result = unsafe {
let mut opts = std::mem::MaybeUninit::zeroed();
let mut sb = std::mem::MaybeUninit::zeroed();
let ret = bcachefs::bch2_read_super(
path.as_ptr(),
opts.as_mut_ptr(),
sb.as_mut_ptr(),
);
if ret == -libc::EACCES {
Err(std::io::Error::new(
std::io::ErrorKind::PermissionDenied,
"no permission",
))
} else if ret != 0 {
Err(std::io::Error::new(
std::io::ErrorKind::Other,
"failed to read super",
))
} else {
Ok((opts.assume_init(), sb.assume_init()))
}
};
match result {
Ok((_, sb)) => match fss.get_mut(&sb.sb().uuid()) {
None => {
let mut fs = FileSystem::new(sb);
fs.devices.push(p.to_owned());
fss.insert(fs.uuid, fs);
}
Some(fs) => {
fs.devices.push(p.to_owned());
}
},
Err(e) if e.kind()
!= std::io::ErrorKind::PermissionDenied =>
{
()
}
e @ Err(_) => {
e?;
}
}
}
}
// Flush stdout so buffered output don't get printed after we remove the gag
unsafe {
libc::fflush(stdout);
}
}
Ok(fss)
}
|
