Samsung Exfat 1.2.5 patch (from https://gerrit.omnirom.org/)

--- a/exfat.c   2013-08-16 12:38:00.000000000 +0700
+++ b/exfat.c   2013-12-22 19:35:32.000000000 +0700
@@ -595,6 +595,8 @@
            num_alloced = p_fs->fs_func->alloc_cluster(sb, num_alloc, &new_clu);
            if (num_alloced == 0)
                break;
+           else if (num_alloced < 0)
+               return FFS_MEDIAERR;

            if (last_clu == CLUSTER_32(~0)) {
                if (new_clu.flags == 0x01)
@@ -1302,7 +1304,9 @@
        new_clu.flags = fid->flags;

        num_alloced = p_fs->fs_func->alloc_cluster(sb, 1, &new_clu);
-       if (num_alloced < 1)
+       if (num_alloced < 0)
+           return FFS_MEDIAERR;
+       else if (num_alloced == 0)
            return FFS_FULL;

        if (last_clu == CLUSTER_32(~0)) {
@@ -1744,16 +1748,19 @@

    for (i = 2; i < p_fs->num_clusters; i++) {
        if (FAT_read(sb, new_clu, &read_clu) != 0)
-           return 0;
+           return -1;

        if (read_clu == CLUSTER_32(0)) {
-           FAT_write(sb, new_clu, CLUSTER_32(~0));
+           if(FAT_write(sb, new_clu, CLUSTER_32(~0)) < 0)
+               return -1;
            num_clusters++;

            if (p_chain->dir == CLUSTER_32(~0))
                p_chain->dir = new_clu;
-           else
-               FAT_write(sb, last_clu, new_clu);
+           else {
+               if(FAT_write(sb, last_clu, new_clu) < 0)
+                   return -1;
+           }

            last_clu = new_clu;

@@ -1805,18 +1812,22 @@
        }

        if (set_alloc_bitmap(sb, new_clu-2) != FFS_SUCCESS)
-           return 0;
+           return -1;

        num_clusters++;

-       if (p_chain->flags == 0x01)
-           FAT_write(sb, new_clu, CLUSTER_32(~0));
+       if (p_chain->flags == 0x01) {
+           if(FAT_write(sb, new_clu, CLUSTER_32(~0)) < 0)
+               return -1;
+       }

        if (p_chain->dir == CLUSTER_32(~0)) {
            p_chain->dir = new_clu;
        } else {
-           if (p_chain->flags == 0x01)
-               FAT_write(sb, last_clu, new_clu);
+           if (p_chain->flags == 0x01) {
+               if(FAT_write(sb, last_clu, new_clu) < 0)
+                   return -1;
+           }
        }
        last_clu = new_clu;

@@ -1879,7 +1890,8 @@
        if (FAT_read(sb, clu, &clu) == -1)
            break;

-       FAT_write(sb, prev, CLUSTER_32(0));
+       if (FAT_write(sb, prev, CLUSTER_32(0)) < 0)
+           break;
        num_clusters++;

    } while (clu != CLUSTER_32(~0));
@@ -2039,7 +2051,8 @@
        return;

    while (len > 1) {
-       FAT_write(sb, chain, chain+1);
+       if (FAT_write(sb, chain, chain+1) < 0)
+           break;
        chain++;
        len--;
    }
@@ -3507,7 +3520,8 @@
            p_fs->hint_uentry.clu.flags = 0x01;
        }
        if (clu.flags == 0x01)
-           FAT_write(sb, last_clu, clu.dir);
+           if(FAT_write(sb, last_clu, clu.dir) < 0)
+               return -1;

        if (p_fs->hint_uentry.entry == -1) {
            p_fs->hint_uentry.dir = p_dir->dir;
@@ -4546,9 +4560,11 @@
    clu.flags = (p_fs->vol_type == EXFAT) ? 0x03 : 0x01;

    ret = p_fs->fs_func->alloc_cluster(sb, 1, &clu);
-   if (ret < 1)
+   if (ret < 0)
+       return FFS_MEDIAERR;
+   else if(ret == 0)
        return FFS_FULL;
-
+
    ret = clear_cluster(sb, clu.dir);
    if (ret != FFS_SUCCESS)
        return ret;
--- b/exfat_super.c 2013-12-22 19:35:32.000000000 +0700
+++ a/exfat_super.c 2013-08-16 12:53:42.000000000 +0700
@@ -60,6 +60,9 @@
 #include <linux/exportfs.h>
 #include <linux/mount.h>
 #include <linux/vfs.h>
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,10,0)
+#include <linux/aio.h>
+#endif
 #include <linux/parser.h>
 #include <linux/uio.h>
 #include <linux/writeback.h>
@@ -1405,12 +1402,17 @@
 static struct inode *exfat_iget(struct super_block *sb, loff_t i_pos) {
    struct exfat_sb_info *sbi = EXFAT_SB(sb);
    struct exfat_inode_info *info;
-   struct hlist_node *node;
    struct hlist_head *head = sbi->inode_hashtable + exfat_hash(i_pos);
    struct inode *inode = NULL;
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3,9,0)
+   struct hlist_node *node;

    spin_lock(&sbi->inode_hash_lock);
    hlist_for_each_entry(info, node, head, i_hash_fat) {
+#else
+   spin_lock(&sbi->inode_hash_lock);
+   hlist_for_each_entry(info, head, i_hash_fat) {
+#endif
        CHECK_ERR(info->vfs_inode.i_sb != sb);

        if (i_pos != info->i_pos)
@@ -1687,7 +1679,7 @@
        info.FreeClusters = info.NumClusters - info.UsedClusters;

        if (p_fs->dev_ejected)
-           return -EIO;
+           printk("[EXFAT] statfs on device is ejected\n");
    }

    buf->f_type = sb->s_magic;
--- a/exfat_version.h   2013-08-14 14:03:26.000000000 +0700
+++ b/exfat_version.h   2013-12-22 19:35:32.000000000 +0700
@@ -1 +1 @@
-#define EXFAT_VERSION  "1.2.4"
+#define EXFAT_VERSION  "1.2.5"