CGroups _s64 files: add cgroups read_s64/write_s64 file methods

[linux-2.6-omap-h63xx.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index b5ef0c4772f766778dbd7ad60895eaf3aa8312eb..bd6122ccc0ba1cae8502ae9d9cae99a6f024e924 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -1299,14 +1299,13 @@ enum cgroup_filetype {
        FILE_RELEASE_AGENT,
 };
 
-static ssize_t cgroup_write_u64(struct cgroup *cgrp, struct cftype *cft,
+static ssize_t cgroup_write_X64(struct cgroup *cgrp, struct cftype *cft,
                                struct file *file,
                                const char __user *userbuf,
                                size_t nbytes, loff_t *unused_ppos)
 {
        char buffer[64];
        int retval = 0;
-       u64 val;
        char *end;
 
        if (!nbytes)
@@ -1318,12 +1317,17 @@ static ssize_t cgroup_write_u64(struct cgroup *cgrp, struct cftype *cft,
 
        buffer[nbytes] = 0;     /* nul-terminate */
        strstrip(buffer);
-       val = simple_strtoull(buffer, &end, 0);
-       if (*end)
-               return -EINVAL;
-
-       /* Pass to subsystem */
-       retval = cft->write_u64(cgrp, cft, val);
+       if (cft->write_u64) {
+               u64 val = simple_strtoull(buffer, &end, 0);
+               if (*end)
+                       return -EINVAL;
+               retval = cft->write_u64(cgrp, cft, val);
+       } else {
+               s64 val = simple_strtoll(buffer, &end, 0);
+               if (*end)
+                       return -EINVAL;
+               retval = cft->write_s64(cgrp, cft, val);
+       }
        if (!retval)
                retval = nbytes;
        return retval;
@@ -1404,8 +1408,8 @@ static ssize_t cgroup_file_write(struct file *file, const char __user *buf,
                return -ENODEV;
        if (cft->write)
                return cft->write(cgrp, cft, file, buf, nbytes, ppos);
-       if (cft->write_u64)
-               return cgroup_write_u64(cgrp, cft, file, buf, nbytes, ppos);
+       if (cft->write_u64 || cft->write_s64)
+               return cgroup_write_X64(cgrp, cft, file, buf, nbytes, ppos);
        return -EINVAL;
 }
 
@@ -1421,6 +1425,18 @@ static ssize_t cgroup_read_u64(struct cgroup *cgrp, struct cftype *cft,
        return simple_read_from_buffer(buf, nbytes, ppos, tmp, len);
 }
 
+static ssize_t cgroup_read_s64(struct cgroup *cgrp, struct cftype *cft,
+                              struct file *file,
+                              char __user *buf, size_t nbytes,
+                              loff_t *ppos)
+{
+       char tmp[64];
+       s64 val = cft->read_s64(cgrp, cft);
+       int len = sprintf(tmp, "%lld\n", (long long) val);
+
+       return simple_read_from_buffer(buf, nbytes, ppos, tmp, len);
+}
+
 static ssize_t cgroup_common_file_read(struct cgroup *cgrp,
                                          struct cftype *cft,
                                          struct file *file,
@@ -1477,6 +1493,8 @@ static ssize_t cgroup_file_read(struct file *file, char __user *buf,
                return cft->read(cgrp, cft, file, buf, nbytes, ppos);
        if (cft->read_u64)
                return cgroup_read_u64(cgrp, cft, file, buf, nbytes, ppos);
+       if (cft->read_s64)
+               return cgroup_read_s64(cgrp, cft, file, buf, nbytes, ppos);
        return -EINVAL;
 }