VFS: simplify stat for pipes

According to POSIX the st_size field of struct stat is undefined for
fifos and anonymous pipes. Thus we can do anything we want. We save a
copy by not being accurate on pipe sizes.
This commit is contained in:
Thomas Veerman 2012-04-18 13:44:33 +00:00
parent db8198d99d
commit 7b81254069
5 changed files with 25 additions and 47 deletions

View file

@ -8,7 +8,6 @@
#include <sys/time.h> #include <sys/time.h>
#endif #endif
struct stat { struct stat {
big_dev_t st_dev; /* inode's device */ big_dev_t st_dev; /* inode's device */
big_mode_t st_mode; /* inode protection mode */ big_mode_t st_mode; /* inode protection mode */
@ -40,7 +39,6 @@ struct stat {
u32_t st_spare[2]; u32_t st_spare[2];
}; };
struct minix_prev_stat { struct minix_prev_stat {
short st_dev; /* major/minor device number */ short st_dev; /* major/minor device number */
ino_t st_ino; /* i-node number */ ino_t st_ino; /* i-node number */
@ -55,20 +53,17 @@ struct minix_prev_stat {
time_t st_ctime; /* time of last file status change */ time_t st_ctime; /* time of last file status change */
}; };
#if defined(_NETBSD_SOURCE) #if defined(_NETBSD_SOURCE)
/* XXX after updating stat struct we don't want to update all the code */
#define st_atime st_atimespec.tv_sec #define st_atime st_atimespec.tv_sec
#define st_mtime st_mtimespec.tv_sec
#define st_ctime st_ctimespec.tv_sec
#define st_birthtime st_birthtimespec.tv_sec
#define st_atimensec st_atimespec.tv_nsec #define st_atimensec st_atimespec.tv_nsec
#define st_mtime st_mtimespec.tv_sec
#define st_mtimensec st_mtimespec.tv_nsec #define st_mtimensec st_mtimespec.tv_nsec
#define st_ctime st_ctimespec.tv_sec
#define st_ctimensec st_ctimespec.tv_nsec #define st_ctimensec st_ctimespec.tv_nsec
#define st_birthtime st_birthtimespec.tv_sec
#define st_birthtimensec st_birthtimespec.tv_nsec #define st_birthtimensec st_birthtimespec.tv_nsec
#endif #endif
#define S_ISUID 0004000 /* set user id on execution */ #define S_ISUID 0004000 /* set user id on execution */
#define S_ISGID 0002000 /* set group id on execution */ #define S_ISGID 0002000 /* set group id on execution */
#if defined(_NETBSD_SOURCE) #if defined(_NETBSD_SOURCE)

View file

@ -155,7 +155,7 @@ static int get_read_vp(struct exec_info *execi, char *fullpath,
return r; return r;
else else
r = req_stat(execi->vp->v_fs_e, execi->vp->v_inode_nr, r = req_stat(execi->vp->v_fs_e, execi->vp->v_inode_nr,
VFS_PROC_NR, (vir_bytes) &(execi->sb), 0, 0); VFS_PROC_NR, (vir_bytes) &(execi->sb), 0);
if (r != OK) return r; if (r != OK) return r;

View file

@ -253,7 +253,7 @@ int req_rmdir(endpoint_t fs_e, ino_t inode_nr, char *lastc);
int req_slink(endpoint_t fs_e, ino_t inode_nr, char *lastc, endpoint_t proc_e, int req_slink(endpoint_t fs_e, ino_t inode_nr, char *lastc, endpoint_t proc_e,
vir_bytes path_addr, size_t path_length, uid_t uid, gid_t gid); vir_bytes path_addr, size_t path_length, uid_t uid, gid_t gid);
int req_stat(endpoint_t fs_e, ino_t inode_nr, endpoint_t proc_e, vir_bytes buf, int req_stat(endpoint_t fs_e, ino_t inode_nr, endpoint_t proc_e, vir_bytes buf,
int pos, int stat_version); int old_stat);
int req_sync(endpoint_t fs_e); int req_sync(endpoint_t fs_e);
int req_unlink(endpoint_t fs_e, ino_t inode_nr, char *lastc); int req_unlink(endpoint_t fs_e, ino_t inode_nr, char *lastc);
int req_unmount(endpoint_t fs_e); int req_unmount(endpoint_t fs_e);

View file

@ -923,7 +923,7 @@ int req_slink(
* req_stat * * req_stat *
*===========================================================================*/ *===========================================================================*/
int req_stat(endpoint_t fs_e, ino_t inode_nr, endpoint_t proc_e, vir_bytes buf, int req_stat(endpoint_t fs_e, ino_t inode_nr, endpoint_t proc_e, vir_bytes buf,
int pos, int stat_version) int old_stat)
{ {
cp_grant_id_t grant_id; cp_grant_id_t grant_id;
int r; int r;
@ -931,12 +931,17 @@ int req_stat(endpoint_t fs_e, ino_t inode_nr, endpoint_t proc_e, vir_bytes buf,
struct stat sb; struct stat sb;
struct minix_prev_stat old_sb; /* for backward compatibility */ struct minix_prev_stat old_sb; /* for backward compatibility */
if (pos != 0 || stat_version != 0) if (old_stat == 1) {
grant_id = cpf_grant_direct(fs_e, (vir_bytes) &sb, /* We're dealing with the old stat() call. First copy stat structure
sizeof(struct stat), CPF_WRITE); * to VFS so we can convert the new struct stat to the old version.
else */
grant_id = cpf_grant_direct(fs_e, (vir_bytes) &sb, sizeof(struct stat),
CPF_WRITE);
} else {
/* Grant FS access to copy straight into user provided buffer */
grant_id = cpf_grant_magic(fs_e, proc_e, buf, sizeof(struct stat), grant_id = cpf_grant_magic(fs_e, proc_e, buf, sizeof(struct stat),
CPF_WRITE); CPF_WRITE);
}
if (grant_id < 0) if (grant_id < 0)
panic("req_stat: cpf_grant_* failed"); panic("req_stat: cpf_grant_* failed");
@ -950,29 +955,16 @@ int req_stat(endpoint_t fs_e, ino_t inode_nr, endpoint_t proc_e, vir_bytes buf,
r = fs_sendrec(fs_e, &m); r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id); cpf_revoke(grant_id);
if (r != OK || (pos == 0 && stat_version == 0)) if (r != OK || old_stat == 0)
return(r); return(r);
if (pos != 0) #if defined(_NETBSD_SOURCE)
sb.st_size -= pos;
if (stat_version == 0) {
r = sys_vircopy(SELF, D, (vir_bytes) &sb, proc_e, D, buf,
sizeof(struct stat));
return(r);
}
/* User needs old struct stat.
* Just 1 prev version at this moment */
assert(stat_version == 1);
/* XXX until that st_Xtime macroses used, we have to undefine them,
* because of minix_prev_stat
*/
#undef st_atime #undef st_atime
#undef st_ctime #undef st_ctime
#undef st_mtime #undef st_mtime
#endif
/* Copy field by field because of st_gid type mismath and /* Copy field by field because of st_gid type mismatch and
* difference in order after atime. * difference in order after atime.
*/ */
old_sb.st_dev = sb.st_dev; old_sb.st_dev = sb.st_dev;

View file

@ -181,7 +181,7 @@ int do_stat()
if (fetch_name(vname1, vname1_length, fullpath) != OK) return(err_code); if (fetch_name(vname1, vname1_length, fullpath) != OK) return(err_code);
if ((vp = eat_path(&resolve, fp)) == NULL) return(err_code); if ((vp = eat_path(&resolve, fp)) == NULL) return(err_code);
r = req_stat(vp->v_fs_e, vp->v_inode_nr, who_e, statbuf, 0, old_stat); r = req_stat(vp->v_fs_e, vp->v_inode_nr, who_e, statbuf, old_stat);
unlock_vnode(vp); unlock_vnode(vp);
unlock_vmnt(vmp); unlock_vmnt(vmp);
@ -197,7 +197,7 @@ int do_fstat()
{ {
/* Perform the fstat(fd, buf) system call. */ /* Perform the fstat(fd, buf) system call. */
register struct filp *rfilp; register struct filp *rfilp;
int r, pipe_pos = 0, old_stat = 0, rfd; int r, old_stat = 0, rfd;
vir_bytes statbuf; vir_bytes statbuf;
statbuf = (vir_bytes) job_m_in.buffer; statbuf = (vir_bytes) job_m_in.buffer;
@ -209,17 +209,8 @@ int do_fstat()
/* Is the file descriptor valid? */ /* Is the file descriptor valid? */
if ((rfilp = get_filp(rfd, VNODE_READ)) == NULL) return(err_code); if ((rfilp = get_filp(rfd, VNODE_READ)) == NULL) return(err_code);
/* If we read from a pipe, send position too */
if (S_ISFIFO(rfilp->filp_vno->v_mode)) {
if (rfilp->filp_mode & R_BIT)
if (ex64hi(rfilp->filp_pos) != 0) {
panic("do_fstat: bad position in pipe");
}
pipe_pos = ex64lo(rfilp->filp_pos);
}
r = req_stat(rfilp->filp_vno->v_fs_e, rfilp->filp_vno->v_inode_nr, r = req_stat(rfilp->filp_vno->v_fs_e, rfilp->filp_vno->v_inode_nr,
who_e, statbuf, pipe_pos, old_stat); who_e, statbuf, old_stat);
unlock_filp(rfilp); unlock_filp(rfilp);
@ -331,7 +322,7 @@ int do_lstat()
old_stat = 1; old_stat = 1;
if (fetch_name(vname1, vname1_length, fullpath) != OK) return(err_code); if (fetch_name(vname1, vname1_length, fullpath) != OK) return(err_code);
if ((vp = eat_path(&resolve, fp)) == NULL) return(err_code); if ((vp = eat_path(&resolve, fp)) == NULL) return(err_code);
r = req_stat(vp->v_fs_e, vp->v_inode_nr, who_e, statbuf, 0, old_stat); r = req_stat(vp->v_fs_e, vp->v_inode_nr, who_e, statbuf, old_stat);
unlock_vnode(vp); unlock_vnode(vp);
unlock_vmnt(vmp); unlock_vmnt(vmp);