From 2036534834841641edf3a6d1e142c4798e146b7b Mon Sep 17 00:00:00 2001
From: rtm <rtm>
Date: Fri, 24 Aug 2007 14:56:17 +0000
Subject: [PATCH] add missing iput() at end of _namei()
---
bootmain.c | 2 +-
fs.c | 10 +++---
mkfs.c | 4 +--
param.h | 2 +-
proc.h | 12 +++----
runoff | 2 +-
usertests.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++++++++
7 files changed, 110 insertions(+), 17 deletions(-)
diff --git a/bootmain.c b/bootmain.c
index 1882aa8..6494c16 100644
--- a/bootmain.c
+++ b/bootmain.c
@@ -12,7 +12,7 @@
// BOOT UP STEPS
// * when the CPU boots it loads the BIOS into memory and executes it
//
-// * the BIOS intializes devices, sets of the interrupt routines, and
+// * the BIOS intializes devices, sets up the interrupt routines, and
// reads the first sector of the boot device(e.g., hard-drive)
// into memory and jumps to it.
//
diff --git a/fs.c b/fs.c
index e47b6fa..a6e1787 100644
--- a/fs.c
+++ b/fs.c
@@ -475,6 +475,7 @@ namecmp(const char *s, const char *t)
// Look for a directory entry in a directory.
// If found, set *poff to byte offset of entry.
+// Caller must have already locked dp.
struct uinode*
dirlookup(struct inode *dp, char *name, uint *poff)
{
@@ -483,7 +484,7 @@ dirlookup(struct inode *dp, char *name, uint *poff)
struct dirent *de;
if(dp->type != T_DIR)
- return 0;
+ panic("dirlookup not DIR");
for(off = 0; off < dp->size; off += BSIZE){
bp = bread(dp->dev, bmap(dp, off / BSIZE, 0));
@@ -558,7 +559,7 @@ dirlink(struct inode *dp, char *name, uint ino)
//
// Examples:
// skipelem("a/bb/c", name) = "bb/c", setting name = "a"
-// skipelem("///a/bb", name) = "b", setting name="a"
+// skipelem("///a/bb", name) = "bb", setting name="a"
// skipelem("", name) = skipelem("////", name) = 0
//
static char*
@@ -617,14 +618,15 @@ _namei(char *path, int parent, char *name)
if((ipu = dirlookup(dp, name, &off)) == 0){
iput(iunlock(dp));
- iput(ipu);
return 0;
}
iput(iunlock(dp));
dpu = ipu;
}
- if(parent)
+ if(parent){
+ iput(dpu);
return 0;
+ }
return dpu;
}
diff --git a/mkfs.c b/mkfs.c
index 462c270..b367f61 100644
--- a/mkfs.c
+++ b/mkfs.c
@@ -8,8 +8,8 @@
#include "param.h"
#include "fs.h"
-int nblocks = 1008;
-int ninodes = 100;
+int nblocks = 995;
+int ninodes = 200;
int size = 1024;
int fsfd;
diff --git a/param.h b/param.h
index 7ceecb5..343288c 100644
--- a/param.h
+++ b/param.h
@@ -6,6 +6,6 @@
#define NFILE 100 // open files per system
#define NBUF 10 // size of disk block cache
#define NREQUEST NBUF // outstanding disk requests
-#define NINODE 100 // maximum number of active i-nodes
+#define NINODE 50 // maximum number of active i-nodes
#define NDEV 10 // maximum major device number
#define ROOTDEV 1 // device number of file system root disk
diff --git a/proc.h b/proc.h
index 9750c15..137bda3 100644
--- a/proc.h
+++ b/proc.h
@@ -43,19 +43,15 @@ struct proc {
char name[16]; // Process name (debugging)
};
-// Process memory is laid out contiguously:
+// Process memory is laid out contiguously, low addresses first:
// text
// original data and bss
// fixed-size stack
// expandable heap
-// If xv6 was only for uniprocessors, this could be
-// struct proc *cp;
-// Instead we have an array curproc, one per
-// processor, and #define cp to the right element
-// in the array. In general such preprocessor
-// subterfuge is to be avoided, but cp is used
-// so often that having the shorthand is worth the ugliness.
+// Arrange that cp point to the struct proc that this
+// CPU is currently running. Such preprocessor
+// subterfuge can be confusing, but saves a lot of typing.
extern struct proc *curproc[NCPU]; // Current (running) process per CPU
#define cp (curproc[cpu()]) // Current process on this CPU
diff --git a/runoff b/runoff
index 092c8b6..3869391 100755
--- a/runoff
+++ b/runoff
@@ -18,7 +18,7 @@ files=`grep -v '^#' runoff.list | awk '{print $1}'`
n=99
for i in $files
do
- runoff1 -n $n $i >fmt/$i
+ ./runoff1 -n $n $i >fmt/$i
nn=`tail -1 fmt/$i | sed 's/ .*//; s/^0*//'`
if [ "x$nn" != x ]; then
n=$nn
diff --git a/usertests.c b/usertests.c
index 7132666..3a9cd9a 100644
--- a/usertests.c
+++ b/usertests.c
@@ -1096,6 +1096,99 @@ rmdot(void)
printf(1, "rmdot ok\n");
}
+void
+dirfile(void)
+{
+ int fd;
+
+ printf(1, "dir vs file\n");
+
+ fd = open("dirfile", O_CREATE);
+ if(fd < 0){
+ printf(1, "create dirfile failed\n");
+ exit();
+ }
+ close(fd);
+ if(chdir("dirfile") == 0){
+ printf(1, "chdir dirfile succeeded!\n");
+ exit();
+ }
+ fd = open("dirfile/xx", 0);
+ if(fd >= 0){
+ printf(1, "create dirfile/xx succeeded!\n");
+ exit();
+ }
+ fd = open("dirfile/xx", O_CREATE);
+ if(fd >= 0){
+ printf(1, "create dirfile/xx succeeded!\n");
+ exit();
+ }
+ if(mkdir("dirfile/xx") == 0){
+ printf(1, "mkdir dirfile/xx succeeded!\n");
+ exit();
+ }
+ if(unlink("dirfile/xx") == 0){
+ printf(1, "unlink dirfile/xx succeeded!\n");
+ exit();
+ }
+ if(link("README", "dirfile/xx") == 0){
+ printf(1, "link to dirfile/xx succeeded!\n");
+ exit();
+ }
+ if(unlink("dirfile") != 0){
+ printf(1, "unlink dirfile failed!\n");
+ exit();
+ }
+
+ fd = open(".", O_RDWR);
+ if(fd >= 0){
+ printf(1, "open . for writing succeeded!\n");
+ exit();
+ }
+ fd = open(".", 0);
+ if(write(fd, "x", 1) > 0){
+ printf(1, "write . succeeded!\n");
+ exit();
+ }
+ close(fd);
+
+ printf(1, "dir vs file OK\n");
+}
+
+// test that iput() is called at the end of _namei()
+void
+iref(void)
+{
+ int i, fd;
+
+ printf(1, "empty file name\n");
+
+ // the 50 is NINODE
+ for(i = 0; i < 50 + 1; i++){
+ if(mkdir("irefd") != 0){
+ printf(1, "mkdir irefd failed\n");
+ exit();
+ }
+ if(chdir("irefd") != 0){
+ printf(1, "chdir irefd failed\n");
+ exit();
+ }
+
+ mkdir("");
+ link("README", "");
+ fd = open("", O_CREATE);
+ if(fd >= 0)
+ close(fd);
+ fd = open("xx", O_CREATE);
+ if(fd >= 0)
+ close(fd);
+ unlink("xx");
+ }
+
+ chdir("/");
+ printf(1, "empty file name OK\n");
+}
+
int
main(int argc, char *argv[])
{
@@ -1128,6 +1221,8 @@ main(int argc, char *argv[])
createdelete();
twofiles();
sharedfd();
+ dirfile();
+ iref();
exectest();
--
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