From: Felix Fietkau Date: Sat, 26 Sep 2009 18:51:05 +0000 (+0000) Subject: add jffs2 whiteout support (necessary for using it with union mounts) X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=ccebfb0bedd5f889bfe4488fc89889e114747abc;p=openwrt%2Fsvn-archive%2Farchive.git add jffs2 whiteout support (necessary for using it with union mounts) SVN-Revision: 17745 --- diff --git a/target/linux/generic-2.6/patches-2.6.31/233-jffs2_whiteout_support.patch b/target/linux/generic-2.6/patches-2.6.31/233-jffs2_whiteout_support.patch new file mode 100644 index 0000000000..72a428237b --- /dev/null +++ b/target/linux/generic-2.6/patches-2.6.31/233-jffs2_whiteout_support.patch @@ -0,0 +1,186 @@ +--- a/fs/jffs2/dir.c ++++ b/fs/jffs2/dir.c +@@ -34,6 +34,9 @@ + static int jffs2_rename (struct inode *, struct dentry *, + struct inode *, struct dentry *); + ++static int jffs2_whiteout (struct inode *, struct dentry *, struct dentry *); ++static int jffs2_fallthru (struct inode *, struct dentry *); ++ + const struct file_operations jffs2_dir_operations = + { + .read = generic_read_dir, +@@ -55,6 +58,8 @@ + .rmdir = jffs2_rmdir, + .mknod = jffs2_mknod, + .rename = jffs2_rename, ++ .fallthru = jffs2_fallthru, ++ .whiteout = jffs2_whiteout, + .permission = jffs2_permission, + .setattr = jffs2_setattr, + .setxattr = jffs2_setxattr, +@@ -98,8 +103,21 @@ + fd = fd_list; + } + } +- if (fd) +- ino = fd->ino; ++ if (fd) { ++ spin_lock(&target->d_lock); ++ switch(fd->type) { ++ case DT_WHT: ++ target->d_flags |= DCACHE_WHITEOUT; ++ break; ++ case DT_UNKNOWN: ++ target->d_flags |= DCACHE_FALLTHRU; ++ break; ++ default: ++ ino = fd->ino; ++ break; ++ } ++ spin_unlock(&target->d_lock); ++ } + mutex_unlock(&dir_f->sem); + if (ino) { + inode = jffs2_iget(dir_i->i_sb, ino); +@@ -155,7 +173,9 @@ + fd->name, fd->ino, fd->type, curofs, offset)); + continue; + } +- if (!fd->ino) { ++ if (fd->type == DT_UNKNOWN) ++ fd->ino = 100; /* XXX: arbitrary */ ++ else if (!fd->ino && (fd->type != DT_WHT)) { + D2(printk(KERN_DEBUG "Skipping deletion dirent \"%s\"\n", fd->name)); + offset++; + continue; +@@ -498,6 +518,11 @@ + return PTR_ERR(inode); + } + ++ if (dentry->d_flags & DCACHE_WHITEOUT) { ++ inode->i_flags |= S_OPAQUE; ++ ri->flags = cpu_to_je16(JFFS2_INO_FLAG_OPAQUE); ++ } ++ + inode->i_op = &jffs2_dir_inode_operations; + inode->i_fop = &jffs2_dir_operations; + +@@ -779,6 +804,82 @@ + return 0; + } + ++static int jffs2_fallthru (struct inode *dir, struct dentry *dentry) ++{ ++ struct jffs2_sb_info *c = JFFS2_SB_INFO(dir->i_sb); ++ uint32_t now; ++ int ret; ++ ++ now = get_seconds(); ++ ret = jffs2_do_link(c, JFFS2_INODE_INFO(dir), 0, DT_UNKNOWN, ++ dentry->d_name.name, dentry->d_name.len, now); ++ if (ret) ++ return ret; ++ ++ d_instantiate(dentry, NULL); ++ spin_lock(&dentry->d_lock); ++ dentry->d_flags |= DCACHE_FALLTHRU; ++ spin_unlock(&dentry->d_lock); ++ ++ return 0; ++} ++ ++static int jffs2_whiteout (struct inode *dir, struct dentry *old_dentry, ++ struct dentry *new_dentry) ++{ ++ struct jffs2_sb_info *c = JFFS2_SB_INFO(dir->i_sb); ++ struct jffs2_inode_info *victim_f = NULL; ++ uint32_t now; ++ int ret; ++ ++ /* If it's a directory, then check whether it is really empty ++ */ ++ if (new_dentry->d_inode) { ++ victim_f = JFFS2_INODE_INFO(old_dentry->d_inode); ++ if (S_ISDIR(old_dentry->d_inode->i_mode)) { ++ struct jffs2_full_dirent *fd; ++ ++ mutex_lock(&victim_f->sem); ++ for (fd = victim_f->dents; fd; fd = fd->next) { ++ if (fd->ino) { ++ mutex_unlock(&victim_f->sem); ++ return -ENOTEMPTY; ++ } ++ } ++ mutex_unlock(&victim_f->sem); ++ } ++ } ++ ++ now = get_seconds(); ++ ret = jffs2_do_link(c, JFFS2_INODE_INFO(dir), 0, DT_WHT, ++ new_dentry->d_name.name, new_dentry->d_name.len, now); ++ if (ret) ++ return ret; ++ ++ spin_lock(&new_dentry->d_lock); ++ new_dentry->d_flags &= ~DCACHE_FALLTHRU; ++ new_dentry->d_flags |= DCACHE_WHITEOUT; ++ spin_unlock(&new_dentry->d_lock); ++ d_add(new_dentry, NULL); ++ ++ if (victim_f) { ++ /* There was a victim. Kill it off nicely */ ++ drop_nlink(old_dentry->d_inode); ++ /* Don't oops if the victim was a dirent pointing to an ++ inode which didn't exist. */ ++ if (victim_f->inocache) { ++ mutex_lock(&victim_f->sem); ++ if (S_ISDIR(old_dentry->d_inode->i_mode)) ++ victim_f->inocache->pino_nlink = 0; ++ else ++ victim_f->inocache->pino_nlink--; ++ mutex_unlock(&victim_f->sem); ++ } ++ } ++ ++ return 0; ++} ++ + static int jffs2_rename (struct inode *old_dir_i, struct dentry *old_dentry, + struct inode *new_dir_i, struct dentry *new_dentry) + { +--- a/fs/jffs2/fs.c ++++ b/fs/jffs2/fs.c +@@ -301,6 +301,10 @@ + + inode->i_op = &jffs2_dir_inode_operations; + inode->i_fop = &jffs2_dir_operations; ++ ++ if (je16_to_cpu(latest_node.flags) & JFFS2_INO_FLAG_OPAQUE) ++ inode->i_flags |= S_OPAQUE; ++ + break; + } + case S_IFREG: +--- a/fs/jffs2/super.c ++++ b/fs/jffs2/super.c +@@ -172,7 +172,7 @@ + + sb->s_op = &jffs2_super_operations; + sb->s_export_op = &jffs2_export_ops; +- sb->s_flags = sb->s_flags | MS_NOATIME; ++ sb->s_flags = sb->s_flags | MS_NOATIME | MS_WHITEOUT; + sb->s_xattr = jffs2_xattr_handlers; + #ifdef CONFIG_JFFS2_FS_POSIX_ACL + sb->s_flags |= MS_POSIXACL; +--- a/include/linux/jffs2.h ++++ b/include/linux/jffs2.h +@@ -87,6 +87,8 @@ + #define JFFS2_INO_FLAG_USERCOMPR 2 /* User has requested a specific + compression type */ + ++#define JFFS2_INO_FLAG_OPAQUE 4 /* Directory is opaque (for union mounts) */ ++ + + /* These can go once we've made sure we've caught all uses without + byteswapping */