tape: sgutils2.rs - add do_out_command()

Make it possible to run commands that writes data.
This commit is contained in:
Dietmar Maurer 2021-01-16 15:15:54 +01:00
parent a9ffa010c8
commit 0c5b9e7820

View File

@ -16,6 +16,12 @@ impl Drop for SgPtBase {
}
}
pub const SCSI_PT_RESULT_GOOD:c_int = 0;
pub const SCSI_PT_RESULT_STATUS:c_int = 1;
pub const SCSI_PT_RESULT_SENSE:c_int = 2;
pub const SCSI_PT_RESULT_TRANSPORT_ERR:c_int = 3;
pub const SCSI_PT_RESULT_OS_ERR:c_int = 4;
#[link(name = "sgutils2")]
extern {
@ -39,6 +45,12 @@ extern {
dxfer_ilen: c_int,
);
pub fn set_scsi_pt_data_out(
objp: *mut SgPtBase,
dxferp: *const u8,
dxfer_olen: c_int,
);
pub fn set_scsi_pt_cdb(
objp: *mut SgPtBase,
cdb: *const u8,
@ -63,6 +75,8 @@ extern {
pub fn get_scsi_pt_sense_len(objp: *const SgPtBase) -> c_int;
pub fn get_scsi_pt_status_response(objp: *const SgPtBase) -> c_int;
pub fn get_scsi_pt_result_category(objp: *const SgPtBase) -> c_int;
}
/// Creates a Box<SgPtBase>
@ -87,6 +101,19 @@ pub struct SgRaw<'a, F> {
sense_buffer: [u8; 32],
}
// alloc page aligned buffer
pub fn alloc_page_aligned_buffer(buffer_size: usize) -> Result<Box<[u8]> , Error> {
let page_size = unsafe { libc::sysconf(libc::_SC_PAGESIZE) } as usize;
let layout = std::alloc::Layout::from_size_align(buffer_size, page_size)?;
let dinp = unsafe { std::alloc::alloc_zeroed(layout) };
if dinp.is_null() {
bail!("alloc SCSI output buffer failed");
}
let buffer_slice = unsafe { std::slice::from_raw_parts_mut(dinp, buffer_size)};
Ok(unsafe { Box::from_raw(buffer_slice) })
}
impl <'a, F: AsRawFd> SgRaw<'a, F> {
/// Create a new instance to run commands
@ -94,15 +121,13 @@ impl <'a, F: AsRawFd> SgRaw<'a, F> {
/// The file must be a handle to a SCSI device.
pub fn new(file: &'a mut F, buffer_size: usize) -> Result<Self, Error> {
let page_size = unsafe { libc::sysconf(libc::_SC_PAGESIZE) } as usize;
let layout = std::alloc::Layout::from_size_align(buffer_size, page_size)?;
let dinp = unsafe { std::alloc::alloc(layout) };
if dinp.is_null() {
bail!("alloc SCSI output buffer failed");
}
let buffer;
let buffer = unsafe { std::slice::from_raw_parts_mut(dinp, buffer_size)};
let buffer = unsafe { Box::from_raw(buffer) };
if buffer_size > 0 {
buffer = alloc_page_aligned_buffer(buffer_size)?;
} else {
buffer = Box::new([]);
}
let sense_buffer = [0u8; 32];
@ -114,13 +139,15 @@ impl <'a, F: AsRawFd> SgRaw<'a, F> {
let mut ptvp = boxed_scsi_pt_obj()?;
unsafe {
set_scsi_pt_data_in(
&mut *ptvp,
self.buffer.as_ptr(),
self.buffer.len() as c_int,
)
};
if self.buffer.len() > 0 {
unsafe {
set_scsi_pt_data_in(
&mut *ptvp,
self.buffer.as_ptr(),
self.buffer.len() as c_int,
)
};
}
unsafe {
set_scsi_pt_sense(
@ -140,6 +167,10 @@ impl <'a, F: AsRawFd> SgRaw<'a, F> {
bail!("no valid SCSI command");
}
if self.buffer.len() < 16 {
bail!("output buffer too small");
}
let mut ptvp = self.create_boxed_scsi_pt_obj()?;
unsafe {
@ -176,4 +207,55 @@ impl <'a, F: AsRawFd> SgRaw<'a, F> {
Ok(&self.buffer[..data_len])
}
/// Run dataout command
///
/// Note: use alloc_page_aligned_buffer to alloc data transfer buffer
pub fn do_out_command(&mut self, cmd: &[u8], data: &[u8]) -> Result<(), Error> {
if !unsafe { sg_is_scsi_cdb(cmd.as_ptr(), cmd.len() as c_int) } {
bail!("no valid SCSI command");
}
let page_size = unsafe { libc::sysconf(libc::_SC_PAGESIZE) } as usize;
if ((data.as_ptr() as usize) & (page_size -1)) != 0 {
bail!("wrong transfer buffer alignment");
}
let mut ptvp = self.create_boxed_scsi_pt_obj()?;
unsafe {
set_scsi_pt_data_out(
&mut *ptvp,
data.as_ptr(),
data.len() as c_int,
);
set_scsi_pt_cdb(
&mut *ptvp,
cmd.as_ptr(),
cmd.len() as c_int,
);
};
let res = unsafe { do_scsi_pt(&mut *ptvp, self.file.as_raw_fd(), 0, 0) };
if res < 0 {
let err = nix::Error::last();
bail!("do_scsi_pt failed - {}", err);
}
if res != 0 {
bail!("do_scsi_pt failed {}", res);
}
// todo: what about sense data?
let _sense_len = unsafe { get_scsi_pt_sense_len(&mut *ptvp) };
let status = unsafe { get_scsi_pt_status_response(&mut *ptvp) };
if status != 0 {
// toto: improve error reporting
bail!("unknown scsi error - status response {}", status);
}
Ok(())
}
}