From: Jan Kara Subject: [PATCH 13/19] tune2fs: Add support for changing number of reserved inodes Date: Fri, 7 Aug 2015 12:51:23 +0200 Message-ID: <1438944689-24562-14-git-send-email-jack@suse.com> References: <1438944689-24562-1-git-send-email-jack@suse.com> Cc: Ted Tso , "Darrick J. Wong" , Jan Kara To: linux-ext4@vger.kernel.org Return-path: Received: from mx2.suse.de ([195.135.220.15]:39169 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752410AbbHGKvr (ORCPT ); Fri, 7 Aug 2015 06:51:47 -0400 In-Reply-To: <1438944689-24562-1-git-send-email-jack@suse.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Signed-off-by: Jan Kara --- misc/tune2fs.8.in | 5 +++ misc/tune2fs.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 107 insertions(+) diff --git a/misc/tune2fs.8.in b/misc/tune2fs.8.in index 4373fc49b255..922705329112 100644 --- a/misc/tune2fs.8.in +++ b/misc/tune2fs.8.in @@ -236,6 +236,11 @@ program. This superblock setting is only honored in 2.6.35+ kernels; and not at all by the ext2 and ext3 file system drivers. .TP +.BI reserved_inodes= number_of_reserved_inodes +Set the number of inodes reserved for system files. This number must be +at least 10. Currently 10 is enough but future features may require additional +reserved inodes. Reserving more inodes requires full file system scan so it +can take a long time. .B test_fs Set a flag in the filesystem superblock indicating that it may be mounted using experimental kernel code, such as the ext4dev filesystem. diff --git a/misc/tune2fs.c b/misc/tune2fs.c index d6bfad3374d1..d6e75fe00814 100644 --- a/misc/tune2fs.c +++ b/misc/tune2fs.c @@ -92,6 +92,7 @@ static char *features_cmd; static char *mntopts_cmd; static int stride, stripe_width; static int stride_set, stripe_width_set; +static unsigned long new_first_ino; static char *extended_cmd; static unsigned long new_inode_size; static char *ext_mount_opts; @@ -2298,6 +2299,34 @@ static int parse_extended_opts(ext2_filsys fs, const char *opts) continue; } ext_mount_opts = strdup(arg); + } else if (!strcmp(token, "reserved_inodes")) { + if (!arg) { + r_usage++; + continue; + } + new_first_ino = strtoul(arg, &p, 0); + if (*p) { + fprintf(stderr, + _("Invalid number of reserved inodes " + "%s\n"), + arg); + r_usage++; + continue; + } + /* Ino 0 is invalid so bump by 1... */ + new_first_ino++; + if (new_first_ino < EXT2_GOOD_OLD_FIRST_INO) { + fprintf(stderr, + _("Too few reserved inodes " + "%s (must be at least %u)\n"), + arg, EXT2_GOOD_OLD_FIRST_INO - 1); + r_usage++; + continue; + } + /* + * Here should go further feature tests to disallow + * admin to free used system inode + */ } else r_usage++; } @@ -2312,6 +2341,7 @@ static int parse_extended_opts(ext2_filsys fs, const char *opts) "\tmount_opts=\n" "\tstride=\n" "\tstripe_width=\n" + "\treserved_inodes=\n" "\ttest_fs\n" "\t^test_fs\n")); free(buf); @@ -2986,6 +3016,75 @@ fs_update_journal_user(struct ext2_super_block *sb, __u8 old_uuid[UUID_SIZE]) return 0; } +/* Zero range of inodes and mark them as free / used */ +static errcode_t zero_inodes_range(ext2_filsys fs, ext2_ino_t start, + ext2_ino_t end, int inuse) +{ + char *inode; + int length = EXT2_INODE_SIZE(fs->super); + ext2_ino_t ino; + errcode_t retval; + + retval = ext2fs_get_memzero(length, &inode); + if (retval) + return retval; + + for (ino = start; ino <= end; ino++) { + ext2fs_inode_alloc_stats(fs, ino, inuse); + retval = ext2fs_write_inode_full(fs, ino, + (struct ext2_inode *)inode, + length); + if (retval) + break; + } + ext2fs_free_mem(inode); + + return retval; +} + +static errcode_t update_reserved_inodes(ext2_filsys fs) +{ + errcode_t retval = 0; + ext2fs_inode_bitmap imap; + ext2_ino_t ino, first_ino = fs->super->s_first_ino; + + if (new_first_ino == first_ino) + return 0; + + /* Group descriptors will need writing as well */ + fs->flags &= ~EXT2_FLAG_SUPER_ONLY; + + /* Freeing reserved inodes is easy */ + if (new_first_ino < first_ino) { + retval = zero_inodes_range(fs, new_first_ino, first_ino - 1, + -1); + if (retval) + return retval; + goto out; + } + + retval = ext2fs_allocate_inode_bitmap(fs, "inodes to move", &imap); + if (retval) + return retval; + + for (ino = fs->super->s_first_ino; ino < new_first_ino; ino++) + ext2fs_mark_inode_bitmap2(imap, ino); + + retval = ext2fs_move_inodes(fs, imap); + ext2fs_free_inode_bitmap(imap); + if (retval) + return retval; + + retval = zero_inodes_range(fs, first_ino, new_first_ino - 1, +1); + if (retval) + return retval; +out: + fs->super->s_first_ino = new_first_ino; + ext2fs_mark_super_dirty(fs); + + return 0; +} + int main(int argc, char **argv) { errcode_t retval; @@ -3404,6 +3503,9 @@ retry_open: if (feature_64bit) convert_64bit(&fs, feature_64bit); + if (new_first_ino) + update_reserved_inodes(fs); + if (rewrite_checksums) rewrite_metadata_checksums(fs); -- 2.1.4