zram: cut trailing newline in algorithm name

Supplied sysfs values sometimes contain new-line symbols (echo vs.  echo
-n), which we also copy as a compression algorithm name.  it works fine
when we lookup for compression algorithm, because we use sysfs_streq()
which takes care of new line symbols.  however, it doesn't look nice when
we print compression algorithm name if zcomp_create() failed:

 zram: Cannot initialise LXZ
            compressing backend

cut trailing new-line, so the error string will look like

  zram: Cannot initialise LXZ compressing backend

we also now can replace sysfs_streq() in zcomp_available_show() with
strcmp().

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/block/zram/zcomp.c b/drivers/block/zram/zcomp.c
index f1ff39a..a1a8b8e 100644 (file)
--- a/drivers/block/zram/zcomp.c
+++ b/drivers/block/zram/zcomp.c
@@ -274,7 +274,7 @@ ssize_t zcomp_available_show(const char *comp, char *buf)
        int i = 0;
 
        while (backends[i]) {
-               if (sysfs_streq(comp, backends[i]->name))
+               if (!strcmp(comp, backends[i]->name))
                        sz += scnprintf(buf + sz, PAGE_SIZE - sz - 2,
                                        "[%s] ", backends[i]->name);
                else

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index a129d52..d94696b 100644 (file)
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -363,6 +363,8 @@ static ssize_t comp_algorithm_store(struct device *dev,
                struct device_attribute *attr, const char *buf, size_t len)
 {
        struct zram *zram = dev_to_zram(dev);
+       size_t sz;
+
        down_write(&zram->init_lock);
        if (init_done(zram)) {
                up_write(&zram->init_lock);
@@ -370,6 +372,12 @@ static ssize_t comp_algorithm_store(struct device *dev,
                return -EBUSY;
        }
        strlcpy(zram->compressor, buf, sizeof(zram->compressor));
+
+       /* ignore trailing newline */
+       sz = strlen(zram->compressor);
+       if (sz > 0 && zram->compressor[sz - 1] == '\n')
+               zram->compressor[sz - 1] = 0x00;
+
        up_write(&zram->init_lock);
        return len;
 }