Use O_EXCL when opening component devices to be assembled into an array

In 2.6, this will fail if the device is already in use, so we can detect this error
more easily.

Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>

diff --git a/Assemble.c b/Assemble.c
index 4e4e12314cce1d20f8eba09d584a1bdf0ca62c2c..ace5717c310adb7dc932b21dd30bc67756025df9 100644 (file)
--- a/Assemble.c
+++ b/Assemble.c
@@ -193,7 +193,7 @@ int Assemble(char *mddev, int mdfd,
                        continue;
                }
                
-               dfd = open(devname, O_RDONLY, 0);
+               dfd = open(devname, O_RDONLY|O_EXCL, 0);
                if (dfd < 0) {
                        if (inargv || verbose)
                                fprintf(stderr, Name ": cannot open device %s: %s\n",
@@ -326,7 +326,7 @@ int Assemble(char *mddev, int mdfd,
                                super.recovery_cp = 0;
                        }
                        super.sb_csum = calc_sb_csum(&super);
-                       dfd = open(devname, O_RDWR, 0);
+                       dfd = open(devname, O_RDWR|O_EXCL, 0);
                        if (dfd < 0) 
                                fprintf(stderr, Name ": Cannot open %s for superblock update\n",
                                        devname);
@@ -435,7 +435,7 @@ int Assemble(char *mddev, int mdfd,
                        devices[chosen_drive].devname, devices[chosen_drive].raid_disk,
                        (int)(devices[chosen_drive].events),
                        (int)(devices[most_recent].events));
-               fd = open(devices[chosen_drive].devname, O_RDWR);
+               fd = open(devices[chosen_drive].devname, O_RDWR|O_EXCL);
                if (fd < 0) {
                        fprintf(stderr, Name ": Couldn't open %s for write - not updating\n",
                                devices[chosen_drive].devname);
@@ -484,7 +484,7 @@ int Assemble(char *mddev, int mdfd,
                if (!devices[j].uptodate)
                        continue;
                chosen_drive = j;
-               if ((fd=open(devices[j].devname, O_RDONLY))< 0) {
+               if ((fd=open(devices[j].devname, O_RDONLY|O_EXCL))< 0) {
                        fprintf(stderr, Name ": Cannot open %s: %s\n",
                                devices[j].devname, strerror(errno));
                        return 1;
@@ -556,7 +556,7 @@ This doesnt work yet
            || (old_linux && (change & 1))) {
                int fd;
                super.sb_csum = calc_sb_csum(&super);
-               fd = open(devices[chosen_drive].devname, O_RDWR);
+               fd = open(devices[chosen_drive].devname, O_RDWR|O_EXCL);
                if (fd < 0) {
                        fprintf(stderr, Name ": Could open %s for write - cannot Assemble array.\n",
                                devices[chosen_drive].devname);

diff --git a/ChangeLog b/ChangeLog
index 7e03a5c04645794d25a0e182eb4565c76e4f5c2d..685485830b185bb97c23e0d205450543fe0e5521 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Changes Prior to 1.10.0 release
+    -   Fix bug with --config=partitions
+    -   Open sub-devices with O_EXCL to detect if already in use
+
 Changes Prior to 1.9.0 release
     -   Fix rpm build problem (stray %)
     -   Minor manpage updates

diff --git a/Create.c b/Create.c
index 1c814f747378ceed52c723852847916172961109..66a88d2008bd03a950971048437c753207df4bb6 100644 (file)
--- a/Create.c
+++ b/Create.c
@@ -187,7 +187,7 @@ int Create(char *mddev, int mdfd,
                array.working_disks++;
                if (dnum < raiddisks)
                        array.active_disks++;
-               fd = open(dname, O_RDONLY, 0);
+               fd = open(dname, O_RDONLY|O_EXCL, 0);
                if (fd <0 ) {
                        fprintf(stderr, Name ": Cannot open %s: %s\n",
                                dname, strerror(errno));
@@ -368,7 +368,7 @@ int Create(char *mddev, int mdfd,
                        disk.minor = 0;
                        disk.state = 1; /* faulty */
                } else {
-                       fd = open(dv->devname, O_RDONLY, 0);
+                       fd = open(dv->devname, O_RDONLY|O_EXCL, 0);
                        if (fd < 0) {
                                fprintf(stderr, Name ": failed to open %s after earlier success - aborting\n",
                                        dv->devname);

diff --git a/Kill.c b/Kill.c
index a57bdf8e484e4f1cd63f7cd927962eb865556bf0..9441f73bb43f88ce4733ac7671e7c2cfc9dd94ab 100644 (file)
--- a/Kill.c
+++ b/Kill.c
@@ -44,7 +44,7 @@ int Kill(char *dev, int force)
        mdp_super_t super;
        int fd, rv = 0;
                
-       fd = open(dev, O_RDWR);
+       fd = open(dev, O_RDWR|O_EXCL);
        if (fd < 0) {
                fprintf(stderr, Name ": Couldn't open %s for write - not zeroing\n",
                        dev);

diff --git a/Manage.c b/Manage.c
index 883509549118972559daee567730d520b8591caa..b323fd3c241b514c24a3138b7f332e09c8841fd8 100644 (file)
--- a/Manage.c
+++ b/Manage.c
@@ -194,6 +194,14 @@ int Manage_subdevs(char *devname, int fd,
                        return 1;
                case 'a':
                        /* add the device - hot or cold */
+                       /* Make sure it isn' in use (in 2.6 or later) */
+                       fd = open(dv->devname, O_RDONLY|O_EXCL);
+                       if (fd < 0) {
+                               fprintf(stderr, Name ": Cannot open %s: %s\n",
+                                       dv->devname, strerror(errno));
+                               return 1;
+                       }
+                       close(fd);
                        if (ioctl(fd, HOT_ADD_DISK, (unsigned long)stb.st_rdev)==0) {
                                fprintf(stderr, Name ": hot added %s\n",
                                        dv->devname);