llapi_pcc_attach(3)

NAME

llapi_pcc_attach, llapi_pcc_attach_fid, llapi_pcc_attach_fid_str - attach a file into PCC

SYNOPSIS

#include <lustre/lustreapi.h>

int llapi_pcc_attach(const char *path, __u32 id,
                     enum lu_pcc_type type);

int llapi_pcc_attach_fid(const char *mntpath, const struct lu_fid *fid,
                         __u32 id, enum lu_pcc_type type);

int llapi_pcc_attach_fid_str(const char *mntpath, const char *fidstr,
                             __u32 id, enum lu_pcc_type type);

DESCRIPTION

The function llapi_pcc_attach(), llapi_pcc_attach_fid() and llapi_pcc_attach_fid_str() tries to attach the file referenced by path, fid, or fidstr into PCC backend. PCC provides a group of local caches and works in two modes: RW-PCC enables a read-write cache on the local SSDs of a single client; RO-PCC provides a read-only cache on the local SSDs of multiple clients. For RW-PCC, the argument id is the archive ID of the copytool agent running on this client. By default, RO-PCC attach ID is setting same with RW-PCC attach ID for a PCC backend if it is also used as read-only caching. The attach mode is specified by type argument, which is a enum lu_pcc_type data structure, which contains the following values:

	LU_PCC_NONE
	LU_PCC_READWRITE
	LU_PCC_READONLY

LU_PCC_NONE

means that the file is not cached on PCC.

LU_PCC_READWRITE

means RW-PCC mode.

LU_PCC_READONLY

means RO-PCC mode.

RETURN VALUES

llapi_pcc_attach() return 0 on success or a negative errno value on failure.

ERRORS

-ENOMEM

Insufficient memory to complete operation.

-EFAULT

Memory region is not properly mapped.

-EINVAL

One or more invalid arguments are given.

-EOPNOTSUPP

PCC attach operation is not supported.

AVAILABILITY

llapi_pcc_attach(), llapi_pcc_attach_fid() and llapi_pcc_attach_fid_str() are part of the lustre(7) user application interface library since release 2.13.0

SEE ALSO

lustreapi(7)