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提交 5051da6d 创建 作者: rtm's avatar rtm
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操作

inode addrs[NDIRECT] -> NADDRS

fix race in mknod / creat use last component in dirent in mknod, not path
上级 74493bf4
隐藏空白字符变更
内嵌 并排
正在显示 包含 208 行增加 和 31 行删除
Notes
浏览文件 @ 5051da6d
...@@ -120,6 +120,11 @@ test: dup() shared fd->off ...@@ -120,6 +120,11 @@ test: dup() shared fd->off
test: indirect blocks. files and directories. test: indirect blocks. files and directories.
test: sbrk test: sbrk
test: does echo foo > x truncate x? test: does echo foo > x truncate x?
test: does create/mkdir/link extract last component correctly?
does namei insist that all the intermediate directories exist?
test: creat/link/mkdir w/ / in name
test: try to create dir ents when intermediate dir doesn't exist
or is a file, not a dir
make proc[0] runnable make proc[0] runnable
cpu early tss and gdt cpu early tss and gdt
......
defs.h
浏览文件 @ 5051da6d
...@@ -119,11 +119,12 @@ void iunlock(struct inode *ip); ...@@ -119,11 +119,12 @@ void iunlock(struct inode *ip);
void idecref(struct inode *ip); void idecref(struct inode *ip);
void iincref(struct inode *ip); void iincref(struct inode *ip);
void iput(struct inode *ip); void iput(struct inode *ip);
struct inode * namei(char *path, int, uint *); struct inode * namei(char *path, int, uint *, char **, struct inode **);
void stati(struct inode *ip, struct stat *st); void stati(struct inode *ip, struct stat *st);
int readi(struct inode *ip, char *xdst, uint off, uint n); int readi(struct inode *ip, char *xdst, uint off, uint n);
int writei(struct inode *ip, char *addr, uint off, uint n); int writei(struct inode *ip, char *addr, uint off, uint n);
struct inode *mknod(char *, short, short, short); struct inode *mknod(char *, short, short, short);
struct inode * mknod1(struct inode *, char *, short, short, short);
int unlink(char *cp); int unlink(char *cp);
void iupdate (struct inode *ip); void iupdate (struct inode *ip);
int link(char *file1, char *file2); int link(char *file1, char *file2);
fs.c
浏览文件 @ 5051da6d
...@@ -241,12 +241,14 @@ bmap(struct inode *ip, uint bn) ...@@ -241,12 +241,14 @@ bmap(struct inode *ip, uint bn)
if (x == 0) if (x == 0)
panic("bmap 2"); panic("bmap 2");
} else { } else {
if(ip->addrs[INDIRECT] == 0)
panic("bmap 3");
inbp = bread(ip->dev, ip->addrs[INDIRECT]); inbp = bread(ip->dev, ip->addrs[INDIRECT]);
a = (uint *) inbp->data; a = (uint *) inbp->data;
x = a[bn - NDIRECT]; x = a[bn - NDIRECT];
brelse(inbp); brelse(inbp);
if (x == 0) if (x == 0)
panic("bmap 3"); panic("bmap 4");
} }
return x; return x;
} }
...@@ -431,11 +433,14 @@ writei(struct inode *ip, char *addr, uint off, uint n) ...@@ -431,11 +433,14 @@ writei(struct inode *ip, char *addr, uint off, uint n)
// look up a path name, in one of three modes. // look up a path name, in one of three modes.
// NAMEI_LOOKUP: return locked target inode. // NAMEI_LOOKUP: return locked target inode.
// NAMEI_CREATE: return locked parent inode. // NAMEI_CREATE: return locked parent inode.
// but return 0 if name does exist. // return 0 if name does exist.
// *ret_last points to last path component (i.e. new file name).
// *ret_ip points to the the name that did exist, if it did.
// *ret_ip and *ret_last may be zero even if return value is zero.
// NAMEI_DELETE: return locked parent inode, offset of dirent in *ret_off. // NAMEI_DELETE: return locked parent inode, offset of dirent in *ret_off.
// return 0 if name doesn't exist. // return 0 if name doesn't exist.
struct inode * struct inode *
namei(char *path, int mode, uint *ret_off) namei(char *path, int mode, uint *ret_off, char **ret_last, struct inode **ret_ip)
{ {
struct inode *dp; struct inode *dp;
struct proc *p = curproc[cpu()]; struct proc *p = curproc[cpu()];
...@@ -445,7 +450,18 @@ namei(char *path, int mode, uint *ret_off) ...@@ -445,7 +450,18 @@ namei(char *path, int mode, uint *ret_off)
struct dirent *ep; struct dirent *ep;
int i, atend; int i, atend;
unsigned ninum; unsigned ninum;
if(mode == NAMEI_DELETE && ret_off == 0)
panic("namei no ret_off");
if(mode == NAMEI_CREATE && ret_last == 0)
panic("namei no ret_last");
if(ret_off)
*ret_off = 0xffffffff;
if(ret_last)
*ret_last = 0;
if(ret_ip)
*ret_ip = 0;
if (*cp == '/') dp = iget(rootdev, 1); if (*cp == '/') dp = iget(rootdev, 1);
else { else {
dp = p->cwd; dp = p->cwd;
...@@ -460,6 +476,10 @@ namei(char *path, int mode, uint *ret_off) ...@@ -460,6 +476,10 @@ namei(char *path, int mode, uint *ret_off)
if(*cp == '\0'){ if(*cp == '\0'){
if(mode == NAMEI_LOOKUP) if(mode == NAMEI_LOOKUP)
return dp; return dp;
if(mode == NAMEI_CREATE && ret_ip){
*ret_ip = dp;
return 0;
}
iput(dp); iput(dp);
return 0; return 0;
} }
...@@ -493,8 +513,14 @@ namei(char *path, int mode, uint *ret_off) ...@@ -493,8 +513,14 @@ namei(char *path, int mode, uint *ret_off)
for(cp1 = cp; *cp1; cp1++) for(cp1 = cp; *cp1; cp1++)
if(*cp1 == '/') if(*cp1 == '/')
atend = 0; atend = 0;
if(mode == NAMEI_CREATE && atend) if(mode == NAMEI_CREATE && atend){
if(*cp == '\0'){
iput(dp);
return 0;
}
*ret_last = cp;
return dp; return dp;
}
iput(dp); iput(dp);
return 0; return 0;
...@@ -521,6 +547,9 @@ wdir(struct inode *dp, char *name, uint ino) ...@@ -521,6 +547,9 @@ wdir(struct inode *dp, char *name, uint ino)
struct dirent de; struct dirent de;
int i; int i;
if(name[0] == '\0')
panic("wdir no name");
for(off = 0; off < dp->size; off += sizeof(de)){ for(off = 0; off < dp->size; off += sizeof(de)){
if(readi(dp, (char *) &de, off, sizeof(de)) != sizeof(de)) if(readi(dp, (char *) &de, off, sizeof(de)) != sizeof(de))
panic("wdir read"); panic("wdir read");
...@@ -529,8 +558,11 @@ wdir(struct inode *dp, char *name, uint ino) ...@@ -529,8 +558,11 @@ wdir(struct inode *dp, char *name, uint ino)
} }
de.inum = ino; de.inum = ino;
for(i = 0; i < DIRSIZ && name[i]; i++) for(i = 0; i < DIRSIZ && name[i]; i++){
if(name[i] == '/')
panic("wdir /");
de.name[i] = name[i]; de.name[i] = name[i];
}
for( ; i < DIRSIZ; i++) for( ; i < DIRSIZ; i++)
de.name[i] = '\0'; de.name[i] = '\0';
...@@ -542,10 +574,23 @@ struct inode * ...@@ -542,10 +574,23 @@ struct inode *
mknod(char *cp, short type, short major, short minor) mknod(char *cp, short type, short major, short minor)
{ {
struct inode *ip, *dp; struct inode *ip, *dp;
char *last;
if ((dp = namei(cp, NAMEI_CREATE, 0)) == 0) if ((dp = namei(cp, NAMEI_CREATE, 0, &last, 0)) == 0)
return 0; return 0;
ip = mknod1(dp, last, type, major, minor);
iput(dp);
return ip;
}
struct inode *
mknod1(struct inode *dp, char *name, short type, short major, short minor)
{
struct inode *ip;
ip = ialloc(dp->dev, type); ip = ialloc(dp->dev, type);
if (ip == 0) { if (ip == 0) {
iput(dp); iput(dp);
...@@ -558,8 +603,8 @@ mknod(char *cp, short type, short major, short minor) ...@@ -558,8 +603,8 @@ mknod(char *cp, short type, short major, short minor)
iupdate (ip); // write new inode to disk iupdate (ip); // write new inode to disk
wdir(dp, cp, ip->inum); wdir(dp, name, ip->inum);
iput(dp);
return ip; return ip;
} }
...@@ -570,7 +615,8 @@ unlink(char *cp) ...@@ -570,7 +615,8 @@ unlink(char *cp)
struct dirent de; struct dirent de;
uint off, inum, dev; uint off, inum, dev;
if ((dp = namei(cp, NAMEI_DELETE, &off)) == 0) dp = namei(cp, NAMEI_DELETE, &off, 0, 0);
if(dp == 0)
return -1; return -1;
dev = dp->dev; dev = dp->dev;
...@@ -604,8 +650,9 @@ int ...@@ -604,8 +650,9 @@ int
link(char *name1, char *name2) link(char *name1, char *name2)
{ {
struct inode *ip, *dp; struct inode *ip, *dp;
char *last;
if ((ip = namei(name1, NAMEI_LOOKUP, 0)) == 0) if ((ip = namei(name1, NAMEI_LOOKUP, 0, 0, 0)) == 0)
return -1; return -1;
if(ip->type == T_DIR){ if(ip->type == T_DIR){
iput(ip); iput(ip);
...@@ -614,7 +661,7 @@ link(char *name1, char *name2) ...@@ -614,7 +661,7 @@ link(char *name1, char *name2)
iunlock(ip); iunlock(ip);
if ((dp = namei(name2, NAMEI_CREATE, 0)) == 0) { if ((dp = namei(name2, NAMEI_CREATE, 0, &last, 0)) == 0) {
idecref(ip); idecref(ip);
return -1; return -1;
} }
...@@ -628,7 +675,7 @@ link(char *name1, char *name2) ...@@ -628,7 +675,7 @@ link(char *name1, char *name2)
ip->nlink += 1; ip->nlink += 1;
iupdate (ip); iupdate (ip);
wdir(dp, name2, ip->inum); wdir(dp, last, ip->inum);
iput(dp); iput(dp);
iput(ip); iput(ip);
......
fs.h
浏览文件 @ 5051da6d
...@@ -9,7 +9,7 @@ struct superblock{ ...@@ -9,7 +9,7 @@ struct superblock{
uint ninodes; uint ninodes;
}; };
#define NADDRS NDIRECT+1 #define NADDRS (NDIRECT+1)
#define NDIRECT 12 #define NDIRECT 12
#define INDIRECT 12 #define INDIRECT 12
#define NINDIRECT (BSIZE / sizeof(uint)) #define NINDIRECT (BSIZE / sizeof(uint))
......
fstests.c
浏览文件 @ 5051da6d
...@@ -213,7 +213,7 @@ unlinkread() ...@@ -213,7 +213,7 @@ unlinkread()
exit(); exit();
} }
fd1 = open("xxx", O_CREATE | O_RDWR); fd1 = open("unlinkread", O_CREATE | O_RDWR);
write(fd1, "yyy", 3); write(fd1, "yyy", 3);
close(fd1); close(fd1);
...@@ -230,7 +230,7 @@ unlinkread() ...@@ -230,7 +230,7 @@ unlinkread()
exit(); exit();
} }
close(fd); close(fd);
unlink("xxx"); unlink("unlinkread");
puts("unlinkread ok\n"); puts("unlinkread ok\n");
} }
...@@ -319,7 +319,7 @@ concreate() ...@@ -319,7 +319,7 @@ concreate()
} else { } else {
fd = open(file, O_CREATE | O_RDWR); fd = open(file, O_CREATE | O_RDWR);
if(fd < 0){ if(fd < 0){
puts("concreate create failed\n"); printf(1, "concreate create %s failed\n", file);
exit(); exit();
} }
close(fd); close(fd);
...@@ -409,12 +409,126 @@ bigdir() ...@@ -409,12 +409,126 @@ bigdir()
puts("bigdir ok\n"); puts("bigdir ok\n");
} }
void
subdir()
{
int fd;
if(mkdir("dd") != 0){
puts("subdir mkdir dd failed\n");
exit();
}
fd = open("dd/ff", O_CREATE | O_RDWR);
if(fd < 0){
puts("create dd/ff failed\n");
exit();
}
write(fd, "ff", 2);
close(fd);
if(mkdir("/dd/dd") != 0){
puts("subdir mkdir dd/dd failed\n");
exit();
}
fd = open("dd/dd/ff", O_CREATE | O_RDWR);
if(fd < 0){
puts("create dd/dd/ff failed\n");
exit();
}
write(fd, "FF", 2);
close(fd);
if(link("dd/dd/ff", "dd/dd/ffff") != 0){
puts("link dd/dd/ff dd/dd/ffff failed\n");
exit();
}
if(unlink("dd/dd/ff") != 0){
puts("unlink dd/dd/ff failed\n");
exit();
}
fd = open("dd/dd/ffff", 0);
if(fd < 0){
puts("open dd/dd/ffff failed\n");
exit();
}
if(read(fd, buf, sizeof(buf)) != 2){
puts("read dd/dd/ffff wrong len\n");
exit();
}
close(fd);
if(open("dd/dd/ff", 0) >= 0){
puts("open dd/dd/ff succeeded!\n");
exit();
}
if(open("dd/ff/ff", O_CREATE|O_RDWR) >= 0){
puts("create dd/ff/ff succeeded!\n");
exit();
}
if(open("dd/xx/ff", O_CREATE|O_RDWR) >= 0){
puts("create dd/xx/ff succeeded!\n");
exit();
}
if(link("dd/ff/ff", "dd/dd/xx") == 0){
puts("link dd/ff/ff dd/dd/xx succeeded!\n");
exit();
}
if(link("dd/xx/ff", "dd/dd/xx") == 0){
puts("link dd/xx/ff dd/dd/xx succeeded!\n");
exit();
}
if(link("dd/ff", "dd/dd/ff") == 0){
puts("link dd/ff dd/dd/ff succeeded!\n");
exit();
}
if(mkdir("dd/ff/ff") == 0){
puts("mkdir dd/ff/ff succeeded!\n");
exit();
}
if(mkdir("dd/xx/ff") == 0){
puts("mkdir dd/xx/ff succeeded!\n");
exit();
}
if(mkdir("dd/dd/ff") == 0){
puts("mkdir dd/dd/ff succeeded!\n");
exit();
}
if(unlink("dd/xx/ff") == 0){
puts("unlink dd/xx/ff succeeded!\n");
exit();
}
if(unlink("dd/ff/ff") == 0){
puts("unlink dd/ff/ff succeeded!\n");
exit();
}
if(unlink("dd/dd/ff") != 0){
puts("unlink dd/dd/ff failed\n");
exit();
}
if(unlink("dd/ff") != 0){
puts("unlink dd/ff failed\n");
exit();
}
// unlink dd/dd
// unlink dd
puts("subdir ok\n");
}
int int
main(int argc, char *argv[]) main(int argc, char *argv[])
{ {
puts("fstests starting\n"); puts("fstests starting\n");
bigdir(); subdir();
// bigdir(); // slow
concreate(); concreate();
linktest(); linktest();
unlinkread(); unlinkread();
......
fsvar.h
浏览文件 @ 5051da6d
...@@ -10,7 +10,7 @@ struct inode { ...@@ -10,7 +10,7 @@ struct inode {
short minor; short minor;
short nlink; short nlink;
uint size; uint size;
uint addrs[NDIRECT]; uint addrs[NADDRS];
}; };
extern uint rootdev; extern uint rootdev;
......
syscall.c
浏览文件 @ 5051da6d
...@@ -219,24 +219,34 @@ int ...@@ -219,24 +219,34 @@ int
sys_open(void) sys_open(void)
{ {
struct proc *cp = curproc[cpu()]; struct proc *cp = curproc[cpu()];
struct inode *ip; struct inode *ip, *dp;
uint arg0, arg1; uint arg0, arg1;
int ufd; int ufd;
struct fd *fd; struct fd *fd;
int l; int l;
char *last;
if(fetcharg(0, &arg0) < 0 || fetcharg(1, &arg1) < 0) if(fetcharg(0, &arg0) < 0 || fetcharg(1, &arg1) < 0)
return -1; return -1;
if((l = checkstring(arg0)) < 0) if((l = checkstring(arg0)) < 0)
return -1; return -1;
if((ip = namei(cp->mem + arg0, NAMEI_LOOKUP, 0)) == 0) {
if (arg1 & O_CREATE) { if(arg1 & O_CREATE){
if (l >= DIRSIZ) dp = namei(cp->mem + arg0, NAMEI_CREATE, 0, &last, &ip);
return -1; if(dp){
ip = mknod (cp->mem + arg0, T_FILE, 0, 0); ip = mknod1(dp, last, T_FILE, 0, 0);
if (ip == 0) return -1; iput(dp);
} else return -1; if(ip == 0)
return -1;
} else if(ip == 0){
return -1;
}
} else {
ip = namei(cp->mem + arg0, NAMEI_LOOKUP, 0, 0, 0);
if(ip == 0)
return -1;
} }
if((fd = fd_alloc()) == 0){ if((fd = fd_alloc()) == 0){
iput(ip); iput(ip);
return -1; return -1;
...@@ -316,7 +326,7 @@ sys_mkdir(void) ...@@ -316,7 +326,7 @@ sys_mkdir(void)
de.inum = nip->inum; de.inum = nip->inum;
writei (nip, (char *) &de, 0, sizeof(de)); writei (nip, (char *) &de, 0, sizeof(de));
pip = namei(".", NAMEI_LOOKUP, 0); pip = namei(".", NAMEI_LOOKUP, 0, 0, 0);
de.inum = pip->inum; de.inum = pip->inum;
de.name[1] = '.'; de.name[1] = '.';
iput(pip); iput(pip);
...@@ -344,7 +354,7 @@ sys_chdir(void) ...@@ -344,7 +354,7 @@ sys_chdir(void)
if(l >= DIRSIZ) if(l >= DIRSIZ)
return -1; return -1;
if ((ip = namei(cp->mem + arg0, NAMEI_LOOKUP, 0)) == 0) if ((ip = namei(cp->mem + arg0, NAMEI_LOOKUP, 0, 0, 0)) == 0)
return -1; return -1;
if (ip == cp->cwd) { if (ip == cp->cwd) {
...@@ -475,7 +485,7 @@ sys_exec(void) ...@@ -475,7 +485,7 @@ sys_exec(void)
return -1; return -1;
if(checkstring(arg0) < 0) if(checkstring(arg0) < 0)
return -1; return -1;
ip = namei(cp->mem + arg0, NAMEI_LOOKUP, 0); ip = namei(cp->mem + arg0, NAMEI_LOOKUP, 0, 0, 0);
if(ip == 0) if(ip == 0)
return -1; return -1;
......
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