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minix/servers/vfs/request.c
Kees van Reeuwijk 94a81c840a Removed unused variables, added const where possible.
2010-04-07 11:25:51 +00:00

1137 lines
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/* This file contains the wrapper functions for issueing a request
* and receiving response from FS processes.
* Each function builds a request message according to the request
* parameter, calls the most low-level fs_sendrec and copies
* back the response.
* The low-level fs_sendrec handles the recovery mechanism from
* a dead driver and reissues the request.
*/
#include "fs.h"
#include <string.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <minix/vfsif.h>
#include <minix/com.h>
#include <minix/const.h>
#include <minix/endpoint.h>
#include <minix/u64.h>
#include <unistd.h>
#include <minix/vfsif.h>
#include "fproc.h"
#include "vmnt.h"
#include "vnode.h"
#include "param.h"
FORWARD _PROTOTYPE(int fs_sendrec_f, (char *file, int line, endpoint_t fs_e,
message *reqm) );
#define fs_sendrec(e, m) fs_sendrec_f(__FILE__, __LINE__, (e), (m))
/*===========================================================================*
* req_breadwrite *
*===========================================================================*/
PUBLIC int req_breadwrite(fs_e, user_e, dev, pos, num_of_bytes, user_addr,
rw_flag, new_posp, cum_iop)
endpoint_t fs_e;
endpoint_t user_e;
dev_t dev;
u64_t pos;
unsigned int num_of_bytes;
char *user_addr;
int rw_flag;
u64_t *new_posp;
unsigned int *cum_iop;
{
int r;
cp_grant_id_t grant_id;
message m;
grant_id = cpf_grant_magic(fs_e, user_e, (vir_bytes) user_addr, num_of_bytes,
(rw_flag == READING ? CPF_WRITE : CPF_READ));
if(grant_id == -1)
panic("req_breadwrite: cpf_grant_magic failed");
/* Fill in request message */
m.m_type = rw_flag == READING ? REQ_BREAD : REQ_BWRITE;
m.REQ_DEV2 = dev;
m.REQ_GRANT = grant_id;
m.REQ_SEEK_POS_LO = ex64lo(pos);
m.REQ_SEEK_POS_HI = ex64hi(pos);
m.REQ_NBYTES = num_of_bytes;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
if (r != OK) return(r);
/* Fill in response structure */
*new_posp = make64(m.RES_SEEK_POS_LO, m.RES_SEEK_POS_HI);
*cum_iop = m.RES_NBYTES;
return(OK);
}
/*===========================================================================*
* req_chmod *
*===========================================================================*/
PUBLIC int req_chmod(fs_e, inode_nr, rmode, new_modep)
int fs_e;
ino_t inode_nr;
mode_t rmode;
mode_t *new_modep;
{
message m;
int r;
/* Fill in request message */
m.m_type = REQ_CHMOD;
m.REQ_INODE_NR = inode_nr;
m.REQ_MODE = rmode;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
/* Copy back actual mode. */
*new_modep = m.RES_MODE;
return(r);
}
/*===========================================================================*
* req_chown *
*===========================================================================*/
PUBLIC int req_chown(fs_e, inode_nr, newuid, newgid, new_modep)
endpoint_t fs_e;
ino_t inode_nr;
uid_t newuid;
gid_t newgid;
mode_t *new_modep;
{
message m;
int r;
/* Fill in request message */
m.m_type = REQ_CHOWN;
m.REQ_INODE_NR = inode_nr;
m.REQ_UID = newuid;
m.REQ_GID = newgid;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
/* Return new mode to caller. */
*new_modep = m.RES_MODE;
return(r);
}
/*===========================================================================*
* req_create *
*===========================================================================*/
int req_create(fs_e, inode_nr, omode, uid, gid, path, res)
int fs_e;
ino_t inode_nr;
int omode;
uid_t uid;
gid_t gid;
char *path;
node_details_t *res;
{
int r;
cp_grant_id_t grant_id;
size_t len;
message m;
if (path[0] == '/')
panic("req_create: filename starts with '/'");
len = strlen(path) + 1;
grant_id = cpf_grant_direct(fs_e, (vir_bytes) path, len, CPF_READ);
if (grant_id == -1)
panic("req_create: cpf_grant_direct failed");
/* Fill in request message */
m.m_type = REQ_CREATE;
m.REQ_INODE_NR = inode_nr;
m.REQ_MODE = omode;
m.REQ_UID = uid;
m.REQ_GID = gid;
m.REQ_GRANT = grant_id;
m.REQ_PATH_LEN = len;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
if (r != OK) return(r);
/* Fill in response structure */
res->fs_e = m.m_source;
res->inode_nr = m.RES_INODE_NR;
res->fmode = m.RES_MODE;
res->fsize = m.RES_FILE_SIZE_LO;
res->uid = m.RES_UID;
res->gid = m.RES_GID;
res->dev = m.RES_DEV;
return(OK);
}
/*===========================================================================*
* req_flush *
*===========================================================================*/
PUBLIC int req_flush(fs_e, dev)
endpoint_t fs_e;
dev_t dev;
{
message m;
/* Fill in request message */
m.m_type = REQ_FLUSH;
m.REQ_DEV = dev;
/* Send/rec request */
return fs_sendrec(fs_e, &m);
}
/*===========================================================================*
* req_fstatfs *
*===========================================================================*/
PUBLIC int req_fstatfs(fs_e, who_e, buf)
int fs_e;
int who_e;
char *buf;
{
int r;
cp_grant_id_t grant_id;
message m;
grant_id = cpf_grant_magic(fs_e, who_e, (vir_bytes) buf, sizeof(struct statfs),
CPF_WRITE);
if(grant_id == -1)
panic("req_fstatfs: cpf_grant_magic failed");
/* Fill in request message */
m.m_type = REQ_FSTATFS;
m.REQ_GRANT = grant_id;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
return(r);
}
/*===========================================================================*
* req_ftrunc *
*===========================================================================*/
PUBLIC int req_ftrunc(fs_e, inode_nr, start, end)
endpoint_t fs_e;
ino_t inode_nr;
off_t start;
off_t end;
{
message m;
/* Fill in request message */
m.m_type = REQ_FTRUNC;
m.REQ_INODE_NR = inode_nr;
m.REQ_TRC_START_LO = start;
m.REQ_TRC_START_HI = 0; /* Not used for now, so clear it. */
m.REQ_TRC_END_LO = end;
m.REQ_TRC_END_HI = 0; /* Not used for now, so clear it. */
/* Send/rec request */
return fs_sendrec(fs_e, &m);
}
/*===========================================================================*
* req_getdents *
*===========================================================================*/
PUBLIC int req_getdents(fs_e, inode_nr, pos, buf, size, new_pos)
endpoint_t fs_e;
ino_t inode_nr;
u64_t pos;
char *buf;
size_t size;
u64_t *new_pos;
{
int r;
message m;
cp_grant_id_t grant_id;
grant_id = cpf_grant_magic(fs_e, who_e, (vir_bytes) buf, size, CPF_WRITE);
if (grant_id < 0)
panic("req_getdents: cpf_grant_magic failed: %d", grant_id);
m.m_type = REQ_GETDENTS;
m.REQ_INODE_NR = inode_nr;
m.REQ_GRANT = grant_id;
m.REQ_MEM_SIZE = size;
m.REQ_SEEK_POS_LO = ex64lo(pos);
m.REQ_SEEK_POS_HI = 0; /* Not used for now, so clear it. */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
if (r == OK) {
*new_pos = cvul64(m.RES_SEEK_POS_LO);
r = m.RES_NBYTES;
}
return(r);
}
/*===========================================================================*
* req_inhibread *
*===========================================================================*/
PUBLIC int req_inhibread(fs_e, inode_nr)
endpoint_t fs_e;
ino_t inode_nr;
{
message m;
/* Fill in request message */
m.m_type = REQ_INHIBREAD;
m.REQ_INODE_NR = inode_nr;
/* Send/rec request */
return fs_sendrec(fs_e, &m);
}
/*===========================================================================*
* req_link *
*===========================================================================*/
PUBLIC int req_link(fs_e, link_parent, lastc, linked_file)
endpoint_t fs_e;
ino_t link_parent;
char *lastc;
ino_t linked_file;
{
int r;
cp_grant_id_t grant_id;
size_t len;
message m;
len = strlen(lastc) + 1;
grant_id = cpf_grant_direct(fs_e, (vir_bytes)lastc, len, CPF_READ);
if(grant_id == -1)
panic("req_link: cpf_grant_direct failed");
/* Fill in request message */
m.m_type = REQ_LINK;
m.REQ_INODE_NR = linked_file;
m.REQ_DIR_INO = link_parent;
m.REQ_GRANT = grant_id;
m.REQ_PATH_LEN = len;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
return(r);
}
/*===========================================================================*
* req_lookup *
*===========================================================================*/
PUBLIC int req_lookup(fs_e, dir_ino, root_ino, uid, gid, flags, res)
endpoint_t fs_e;
ino_t dir_ino;
ino_t root_ino;
uid_t uid;
gid_t gid;
int flags;
lookup_res_t *res;
{
int r;
size_t len;
cp_grant_id_t grant_id, grant_id2;
message m;
vfs_ucred_t credentials;
grant_id = cpf_grant_direct(fs_e, (vir_bytes) user_fullpath,
sizeof(user_fullpath), CPF_READ | CPF_WRITE);
if(grant_id == -1)
panic("req_lookup: cpf_grant_direct failed");
len = strlen(user_fullpath) + 1;
m.m_type = REQ_LOOKUP;
m.REQ_GRANT = grant_id;
m.REQ_PATH_LEN = len;
m.REQ_PATH_SIZE = sizeof(user_fullpath);
m.REQ_DIR_INO = dir_ino;
m.REQ_ROOT_INO = root_ino;
if(fp->fp_ngroups > 0) { /* Is the process member of multiple groups? */
/* In that case the FS has to copy the uid/gid credentials */
int i;
/* Set credentials */
credentials.vu_uid = fp->fp_effuid;
credentials.vu_gid = fp->fp_effgid;
credentials.vu_ngroups = fp->fp_ngroups;
for (i = 0; i < fp->fp_ngroups; i++)
credentials.vu_sgroups[i] = fp->fp_sgroups[i];
grant_id2 = cpf_grant_direct(fs_e, (vir_bytes) &credentials,
sizeof(credentials), CPF_READ);
if(grant_id2 == -1)
panic("req_lookup: cpf_grant_direct failed");
m.REQ_GRANT2 = grant_id2;
m.REQ_UCRED_SIZE= sizeof(credentials);
flags |= PATH_GET_UCRED;
} else {
/* When there's only one gid, we can send it directly */
m.REQ_UID = uid;
m.REQ_GID = gid;
flags &= ~PATH_GET_UCRED;
}
m.REQ_FLAGS = flags;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
if(fp->fp_ngroups > 0) cpf_revoke(grant_id2);
/* Fill in response according to the return value */
res->fs_e = m.m_source;
switch (r) {
case OK:
res->inode_nr = m.RES_INODE_NR;
res->fmode = m.RES_MODE;
res->fsize = m.RES_FILE_SIZE_LO;
res->dev = m.RES_DEV;
res->uid= m.RES_UID;
res->gid= m.RES_GID;
break;
case EENTERMOUNT:
res->inode_nr = m.RES_INODE_NR;
res->char_processed = m.RES_OFFSET;
res->symloop = m.RES_SYMLOOP;
break;
case ELEAVEMOUNT:
res->char_processed = m.RES_OFFSET;
res->symloop = m.RES_SYMLOOP;
break;
case ESYMLINK:
res->char_processed = m.RES_OFFSET;
res->symloop = m.RES_SYMLOOP;
break;
default:
break;
}
return(r);
}
/*===========================================================================*
* req_mkdir *
*===========================================================================*/
PUBLIC int req_mkdir(fs_e, inode_nr, lastc, uid, gid, dmode)
endpoint_t fs_e;
ino_t inode_nr;
char *lastc;
uid_t uid;
gid_t gid;
mode_t dmode;
{
int r;
cp_grant_id_t grant_id;
size_t len;
message m;
len = strlen(lastc) + 1;
grant_id = cpf_grant_direct(fs_e, (vir_bytes)lastc, len, CPF_READ);
if(grant_id == -1)
panic("req_mkdir: cpf_grant_direct failed");
/* Fill in request message */
m.m_type = REQ_MKDIR;
m.REQ_INODE_NR = inode_nr;
m.REQ_MODE = dmode;
m.REQ_UID = uid;
m.REQ_GID = gid;
m.REQ_GRANT = grant_id;
m.REQ_PATH_LEN = len;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
return(r);
}
/*===========================================================================*
* req_mknod *
*===========================================================================*/
PUBLIC int req_mknod(fs_e, inode_nr, lastc, uid, gid, dmode, dev)
endpoint_t fs_e;
ino_t inode_nr;
char *lastc;
uid_t uid;
gid_t gid;
mode_t dmode;
dev_t dev;
{
int r;
size_t len;
cp_grant_id_t grant_id;
message m;
len = strlen(lastc) + 1;
grant_id = cpf_grant_direct(fs_e, (vir_bytes)lastc, len, CPF_READ);
if(grant_id == -1)
panic("req_mknod: cpf_grant_direct failed");
/* Fill in request message */
m.m_type = REQ_MKNOD;
m.REQ_INODE_NR = inode_nr;
m.REQ_MODE = dmode;
m.REQ_DEV = dev;
m.REQ_UID = uid;
m.REQ_GID = gid;
m.REQ_GRANT = grant_id;
m.REQ_PATH_LEN = len;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
return(r);
}
/*===========================================================================*
* req_mountpoint *
*===========================================================================*/
PUBLIC int req_mountpoint(fs_e, inode_nr)
endpoint_t fs_e;
ino_t inode_nr;
{
message m;
/* Fill in request message */
m.m_type = REQ_MOUNTPOINT;
m.REQ_INODE_NR = inode_nr;
/* Send/rec request */
return fs_sendrec(fs_e, &m);
}
/*===========================================================================*
* req_newnode *
*===========================================================================*/
PUBLIC int req_newnode(fs_e, uid, gid, dmode, dev, res)
endpoint_t fs_e;
uid_t uid;
gid_t gid;
mode_t dmode;
dev_t dev;
struct node_details *res;
{
int r;
message m;
/* Fill in request message */
m.m_type = REQ_NEWNODE;
m.REQ_MODE = dmode;
m.REQ_DEV = dev;
m.REQ_UID = uid;
m.REQ_GID = gid;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
res->fs_e = m.m_source;
res->inode_nr = m.RES_INODE_NR;
res->fmode = m.RES_MODE;
res->fsize = m.RES_FILE_SIZE_LO;
res->dev = m.RES_DEV;
res->uid = m.RES_UID;
res->gid = m.RES_GID;
return(r);
}
/*===========================================================================*
* req_newdriver *
*===========================================================================*/
PUBLIC int req_newdriver(fs_e, dev, driver_e)
endpoint_t fs_e;
Dev_t dev;
endpoint_t driver_e;
{
/* Note: this is the only request function that doesn't use the
* fs_sendrec internal routine, since we want to avoid the dead
* driver recovery mechanism here. This function is actually called
* during the recovery.
*/
message m;
int r;
/* Fill in request message */
m.m_type = REQ_NEW_DRIVER;
m.REQ_DEV = dev;
m.REQ_DRIVER_E = driver_e;
/* Issue request */
if((r = sendrec(fs_e, &m)) != OK) {
printf("%s:%d VFS req_newdriver: error sending message %d to %d\n",
__FILE__, __LINE__, r, fs_e);
util_stacktrace();
return(r);
}
return(OK);
}
/*===========================================================================*
* req_putnode *
*===========================================================================*/
PUBLIC int req_putnode(fs_e, inode_nr, count)
int fs_e;
ino_t inode_nr;
int count;
{
message m;
/* Fill in request message */
m.m_type = REQ_PUTNODE;
m.REQ_INODE_NR = inode_nr;
m.REQ_COUNT = count;
/* Send/rec request */
return fs_sendrec(fs_e, &m);
}
/*===========================================================================*
* req_rdlink *
*===========================================================================*/
PUBLIC int req_rdlink(fs_e, inode_nr, who_e, buf, len)
endpoint_t fs_e;
ino_t inode_nr;
endpoint_t who_e;
char *buf;
size_t len;
{
message m;
int r;
cp_grant_id_t grant_id;
grant_id = cpf_grant_magic(fs_e, who_e, (vir_bytes) buf, len, CPF_WRITE);
if(grant_id == -1)
panic("req_rdlink: cpf_grant_magic failed");
/* Fill in request message */
m.m_type = REQ_RDLINK;
m.REQ_INODE_NR = inode_nr;
m.REQ_GRANT = grant_id;
m.REQ_MEM_SIZE = len;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
if(r == OK) r = m.RES_NBYTES;
return(r);
}
/*===========================================================================*
* req_readsuper *
*===========================================================================*/
PUBLIC int req_readsuper(fs_e, label, dev, readonly, isroot, res_nodep)
endpoint_t fs_e;
char *label;
dev_t dev;
int readonly;
int isroot;
struct node_details *res_nodep;
{
int r;
cp_grant_id_t grant_id;
size_t len;
message m;
len = strlen(label)+1;
grant_id = cpf_grant_direct(fs_e, (vir_bytes) label, len, CPF_READ);
if (grant_id == -1)
panic("req_readsuper: cpf_grant_direct failed");
/* Fill in request message */
m.m_type = REQ_READSUPER;
m.REQ_FLAGS = 0;
if(readonly) m.REQ_FLAGS |= REQ_RDONLY;
if(isroot) m.REQ_FLAGS |= REQ_ISROOT;
m.REQ_GRANT = grant_id;
m.REQ_DEV = dev;
m.REQ_PATH_LEN = len;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
if(r == OK) {
/* Fill in response structure */
res_nodep->fs_e = m.m_source;
res_nodep->inode_nr = m.RES_INODE_NR;
res_nodep->fmode = m.RES_MODE;
res_nodep->fsize = m.RES_FILE_SIZE_LO;
res_nodep->uid = m.RES_UID;
res_nodep->gid = m.RES_GID;
}
return(r);
}
/*===========================================================================*
* req_readwrite *
*===========================================================================*/
PUBLIC int req_readwrite(fs_e, inode_nr, pos, rw_flag, user_e,
user_addr, num_of_bytes, new_posp, cum_iop)
endpoint_t fs_e;
ino_t inode_nr;
u64_t pos;
int rw_flag;
endpoint_t user_e;
char *user_addr;
unsigned int num_of_bytes;
u64_t *new_posp;
unsigned int *cum_iop;
{
int r;
cp_grant_id_t grant_id;
message m;
if (ex64hi(pos) != 0)
panic("req_readwrite: pos too large");
grant_id = cpf_grant_magic(fs_e, user_e, (vir_bytes) user_addr, num_of_bytes,
(rw_flag==READING ? CPF_WRITE:CPF_READ));
if (grant_id == -1)
panic("req_readwrite: cpf_grant_magic failed");
/* Fill in request message */
m.m_type = rw_flag == READING ? REQ_READ : REQ_WRITE;
m.REQ_INODE_NR = inode_nr;
m.REQ_GRANT = grant_id;
m.REQ_SEEK_POS_LO = ex64lo(pos);
m.REQ_SEEK_POS_HI = 0; /* Not used for now, so clear it. */
m.REQ_NBYTES = num_of_bytes;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
if (r == OK) {
/* Fill in response structure */
*new_posp = cvul64(m.RES_SEEK_POS_LO);
*cum_iop = m.RES_NBYTES;
}
return(r);
}
/*===========================================================================*
* req_rename *
*===========================================================================*/
PUBLIC int req_rename(fs_e, old_dir, old_name, new_dir, new_name)
endpoint_t fs_e;
ino_t old_dir;
char *old_name;
ino_t new_dir;
char *new_name;
{
int r;
cp_grant_id_t gid_old, gid_new;
size_t len_old, len_new;
message m;
len_old = strlen(old_name) + 1;
gid_old = cpf_grant_direct(fs_e, (vir_bytes) old_name, len_old, CPF_READ);
if(gid_old == -1)
panic("req_rename: cpf_grant_direct failed");
len_new = strlen(new_name) + 1;
gid_new = cpf_grant_direct(fs_e, (vir_bytes) new_name, len_new, CPF_READ);
if(gid_new == -1)
panic("req_rename: cpf_grant_direct failed");
/* Fill in request message */
m.m_type = REQ_RENAME;
m.REQ_REN_OLD_DIR = old_dir;
m.REQ_REN_NEW_DIR = new_dir;
m.REQ_REN_GRANT_OLD = gid_old;
m.REQ_REN_LEN_OLD = len_old;
m.REQ_REN_GRANT_NEW = gid_new;
m.REQ_REN_LEN_NEW = len_new;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(gid_old);
cpf_revoke(gid_new);
return(r);
}
/*===========================================================================*
* req_rmdir *
*===========================================================================*/
PUBLIC int req_rmdir(fs_e, inode_nr, lastc)
endpoint_t fs_e;
ino_t inode_nr;
char *lastc;
{
int r;
cp_grant_id_t grant_id;
size_t len;
message m;
len = strlen(lastc) + 1;
grant_id = cpf_grant_direct(fs_e, (vir_bytes) lastc, len, CPF_READ);
if(grant_id == -1)
panic("req_rmdir: cpf_grant_direct failed");
/* Fill in request message */
m.m_type = REQ_RMDIR;
m.REQ_INODE_NR = inode_nr;
m.REQ_GRANT = grant_id;
m.REQ_PATH_LEN = len;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
return(r);
}
/*===========================================================================*
* req_slink *
*===========================================================================*/
PUBLIC int req_slink(fs_e, inode_nr, lastc, who_e, path_addr, path_length,
uid, gid)
endpoint_t fs_e;
ino_t inode_nr;
char *lastc;
endpoint_t who_e;
char *path_addr;
unsigned short path_length;
uid_t uid;
gid_t gid;
{
int r;
size_t len;
cp_grant_id_t gid_name, gid_buf;
message m;
len = strlen(lastc) + 1;
gid_name = cpf_grant_direct(fs_e, (vir_bytes) lastc, len, CPF_READ);
if(gid_name == -1)
panic("req_slink: cpf_grant_direct failed");
gid_buf = cpf_grant_magic(fs_e, who_e, (vir_bytes) path_addr, path_length,
CPF_READ);
if(gid_buf == -1) {
cpf_revoke(gid_name);
panic("req_slink: cpf_grant_magic failed");
}
/* Fill in request message */
m.m_type = REQ_SLINK;
m.REQ_INODE_NR = inode_nr;
m.REQ_UID = uid;
m.REQ_GID = gid;
m.REQ_GRANT = gid_name;
m.REQ_PATH_LEN = len;
m.REQ_GRANT3 = gid_buf;
m.REQ_MEM_SIZE = path_length;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(gid_name);
cpf_revoke(gid_buf);
return(r);
}
/*===========================================================================*
* req_stat *
*===========================================================================*/
PUBLIC int req_stat(fs_e, inode_nr, who_e, buf, pos)
int fs_e;
ino_t inode_nr;
int who_e;
char *buf;
int pos;
{
cp_grant_id_t grant_id;
int r;
message m;
struct stat sb;
if (pos != 0)
grant_id = cpf_grant_direct(fs_e, (vir_bytes) &sb,
sizeof(struct stat), CPF_WRITE);
else
grant_id = cpf_grant_magic(fs_e, who_e, (vir_bytes) buf,
sizeof(struct stat), CPF_WRITE);
if (grant_id < 0)
panic("req_stat: cpf_grant_* failed");
/* Fill in request message */
m.m_type = REQ_STAT;
m.REQ_INODE_NR = inode_nr;
m.REQ_GRANT = grant_id;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
if (r == OK && pos != 0) {
sb.st_size -= pos;
r = sys_vircopy(SELF, D, (vir_bytes) &sb, who_e, D, (vir_bytes) buf,
sizeof(struct stat));
}
return(r);
}
/*===========================================================================*
* req_sync *
*===========================================================================*/
PUBLIC int req_sync(fs_e)
endpoint_t fs_e;
{
message m;
/* Fill in request message */
m.m_type = REQ_SYNC;
/* Send/rec request */
return fs_sendrec(fs_e, &m);
}
/*===========================================================================*
* req_unlink *
*===========================================================================*/
PUBLIC int req_unlink(fs_e, inode_nr, lastc)
endpoint_t fs_e;
ino_t inode_nr;
char *lastc;
{
cp_grant_id_t grant_id;
size_t len;
int r;
message m;
len = strlen(lastc) + 1;
grant_id = cpf_grant_direct(fs_e, (vir_bytes) lastc, len, CPF_READ);
if(grant_id == -1)
panic("req_unlink: cpf_grant_direct failed");
/* Fill in request message */
m.m_type = REQ_UNLINK;
m.REQ_INODE_NR = inode_nr;
m.REQ_GRANT = grant_id;
m.REQ_PATH_LEN = len;
/* Send/rec request */
r = fs_sendrec(fs_e, &m);
cpf_revoke(grant_id);
return(r);
}
/*===========================================================================*
* req_unmount *
*===========================================================================*/
PUBLIC int req_unmount(fs_e)
endpoint_t fs_e;
{
message m;
/* Fill in request message */
m.m_type = REQ_UNMOUNT;
/* Send/rec request */
return fs_sendrec(fs_e, &m);
}
/*===========================================================================*
* req_utime *
*===========================================================================*/
PUBLIC int req_utime(fs_e, inode_nr, actime, modtime)
endpoint_t fs_e;
ino_t inode_nr;
time_t actime;
time_t modtime;
{
message m;
/* Fill in request message */
m.m_type = REQ_UTIME;
m.REQ_INODE_NR = inode_nr;
m.REQ_ACTIME = actime;
m.REQ_MODTIME = modtime;
/* Send/rec request */
return fs_sendrec(fs_e, &m);
}
/*===========================================================================*
* fs_sendrec *
*===========================================================================*/
PRIVATE int fs_sendrec_f(char *file, int line, endpoint_t fs_e, message *reqm)
{
/* This is the low level function that sends requests to FS processes.
* It also handles driver recovery mechanism and reissuing the
* request which failed due to a dead driver.
*/
int r, old_driver_e;
message origm, m;
if(fs_e <= 0 || fs_e == NONE)
panic("talking to bogus endpoint: %d", fs_e);
/* Make a copy of the request so that we can load it back in
* case of a dead driver */
origm = *reqm;
/* In response to the request we sent, some file systems may send back their
* own VFS request, instead of a reply. VFS currently offers limited support
* for this. As long as the FS keeps sending requests, we process them and
* send back a reply. We break out of the loop as soon as the FS sends a
* reply to the original request.
*
* There is no form of locking or whatever on global data structures, so it
* is quite easy to mess things up; hence, 'limited' support. A future async
* VFS will solve this problem for good.
*/
for (;;) {
/* Do the actual send, receive */
if (OK != (r = sendrec(fs_e, reqm))) {
printf("VFS:fs_sendrec:%s:%d: error sending message. "
"FS_e: %d req_nr: %d err: %d\n", file, line, fs_e,
reqm->m_type, r);
util_stacktrace();
return(r);
}
/* If the type field is 0 (OK) or negative (E*), this is a reply. If it
* contains a positive nonzero value, this is a request.
*/
if (reqm->m_type <= 0)
break; /* Reply */
if (reqm->m_type == -EENTERMOUNT || reqm->m_type == -ELEAVEMOUNT ||
reqm->m_type == -ESYMLINK) {
reqm->m_type = -reqm->m_type;
break; /* Reply */
}
/* Request */
nested_fs_call(reqm);
}
#if 0
if(r == OK) {
/* Sendrec was okay */
break;
}
/* Dead driver */
if (r == EDEADSRCDST || r == EDSTDIED || r == ESRCDIED) {
old_driver_e = NONE;
/* Find old driver by endpoint */
for (vmp = &vmnt[0]; vmp < &vmnt[NR_MNTS]; ++vmp) {
if (vmp->m_fs_e == fs_e) { /* found FS */
#if 0
old_driver_e = vmp->m_driver_e;
#endif
dmap_unmap_by_endpt(old_driver_e); /* unmap driver */
break;
}
}
/* No FS ?? */
if (old_driver_e == NONE)
panic("VFSdead_driver: couldn't find FS: %d", fs_e);
/* Wait for a new driver. */
for (;;) {
new_driver_e = 0;
printf("VFSdead_driver: waiting for new driver\n");
r = sef_receive(RS_PROC_NR, &m);
if (r != OK) {
panic("VFSdead_driver: unable to receive from RS: %d", r);
}
if (m.m_type == DEVCTL) {
/* Map new driver */
r = fs_devctl(m.ctl_req, m.dev_nr, m.driver_nr,
m.dev_style, m.m_force);
if (m.ctl_req == DEV_MAP && r == OK) {
new_driver_e = m.driver_nr;
printf("VFSdead_driver: new driver endpoint: %d\n",
new_driver_e);
}
}
else {
panic("VFSdead_driver: got message from RS type: %d", m.m_type);
}
m.m_type = r;
if ((r = send(RS_PROC_NR, &m)) != OK) {
panic("VFSdead_driver: unable to send to RS: %d", r);
}
/* New driver is ready */
if (new_driver_e) break;
}
/* Copy back original request */
*reqm = origm;
continue;
}
printf("fs_sendrec: unhandled error %d sending to %d\n", r, fs_e);
panic("fs_sendrec: unhandled error");
}
#endif
/* Return message type */
return(reqm->m_type);
}
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