Commit f0853122 authored by Committed by Eric Van HensbergenBrowse files
9p: getattr client implementation for 9P2000.L protocol.
SYNOPSIS size Tgetattr tag fid request_mask size Rgetattr tag lstat[n] DESCRIPTION The getattr transaction inquires about the file identified by fid. request_mask is a bit mask that specifies which fields of the stat structure is the client interested in. The reply will contain a machine-independent directory entry, laid out as follows: st_result_mask Bit mask that indicates which fields in the stat structure have been populated by the server qid.type the type of the file (directory, etc.), represented as a bit vector corresponding to the high 8 bits of the file's mode word. qid.vers version number for given path qid.path the file server's unique identification for the file st_mode Permission and flags st_uid User id of owner st_gid Group ID of owner st_nlink Number of hard links st_rdev Device ID (if special file) st_size Size, in bytes st_blksize Block size for file system IO st_blocks Number of file system blocks allocated st_atime_sec Time of last access, seconds st_atime_nsec Time of last access, nanoseconds st_mtime_sec Time of last modification, seconds st_mtime_nsec Time of last modification, nanoseconds st_ctime_sec Time of last status change, seconds st_ctime_nsec Time of last status change, nanoseconds st_btime_sec Time of creation (birth) of file, seconds st_btime_nsec Time of creation (birth) of file, nanoseconds st_gen Inode generation st_data_version Data version number request_mask and result_mask bit masks contain the following bits #define P9_STATS_MODE 0x00000001ULL #define P9_STATS_NLINK 0x00000002ULL #define P9_STATS_UID 0x00000004ULL #define P9_STATS_GID 0x00000008ULL #define P9_STATS_RDEV 0x00000010ULL #define P9_STATS_ATIME 0x00000020ULL #define P9_STATS_MTIME 0x00000040ULL #define P9_STATS_CTIME 0x00000080ULL #define P9_STATS_INO 0x00000100ULL #define P9_STATS_SIZE 0x00000200ULL #define P9_STATS_BLOCKS 0x00000400ULL #define P9_STATS_BTIME 0x00000800ULL #define P9_STATS_GEN 0x00001000ULL #define P9_STATS_DATA_VERSION 0x00002000ULL #define P9_STATS_BASIC 0x000007ffULL #define P9_STATS_ALL 0x00003fffULL This patch implements the client side of getattr implementation for 9P2000.L. It introduces a new structure p9_stat_dotl for getting Linux stat information along with QID. The data layout is similar to stat structure in Linux user space with the following major differences: inode (st_ino) is not part of data. Instead qid is. device (st_dev) is not part of data because this doesn't make sense on the client. All time variables are 64 bit wide on the wire. The kernel seems to use 32 bit variables for these variables. However, some of the architectures have used 64 bit variables and glibc exposes 64 bit variables to user space on some architectures. Hence to be on the safer side we have made these 64 bit in the protocol. Refer to the comments in include/asm-generic/stat.h There are some additional fields: st_btime_sec, st_btime_nsec, st_gen, st_data_version apart from the bitmask, st_result_mask. The bit mask is filled by the server to indicate which stat fields have been populated by the server. Currently there is no clean way for the server to obtain these additional fields, so it sends back just the basic fields. Signed-off-by: Sripathi Kodi <email@example.com> Signed-off-by: Eric Van Hensbegren <firstname.lastname@example.org>