From 18ecbfd3dd11e07ee5dbcaa8c2bbde0c5f64ade6 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Wed, 11 Sep 2024 18:38:12 +0930 Subject: [PATCH] btrfs-progs: open the devices exclusively for writes There is an internal report that, during btrfs-convert to block-group tree, by accident some systemd events triggered the mount of the target fs. This leads to double mount (one by kernel and one by the btrfs-progs), which seems to cause quite some problems. To avoid such accident, exclusively opens all devices if btrfs-progs is doing write operations. Pull-request: #888 Reported-by: pandada8 Signed-off-by: Qu Wenruo --- cmds/rescue.c | 6 +++--- common/filesystem-utils.c | 3 ++- convert/main.c | 3 ++- image/image-restore.c | 4 +++- mkfs/main.c | 3 ++- tune/main.c | 2 +- 6 files changed, 13 insertions(+), 8 deletions(-) diff --git a/cmds/rescue.c b/cmds/rescue.c index 6d7d526d..5bbd47e5 100644 --- a/cmds/rescue.c +++ b/cmds/rescue.c @@ -203,7 +203,7 @@ static int cmd_rescue_zero_log(const struct cmd_struct *cmd, } root = open_ctree(devname, 0, OPEN_CTREE_WRITES | OPEN_CTREE_PARTIAL | - OPEN_CTREE_NO_BLOCK_GROUPS); + OPEN_CTREE_NO_BLOCK_GROUPS | OPEN_CTREE_EXCLUSIVE); if (!root) { error("could not open ctree"); return 1; @@ -258,7 +258,7 @@ static int cmd_rescue_fix_device_size(const struct cmd_struct *cmd, } oca.filename = devname; - oca.flags = OPEN_CTREE_WRITES | OPEN_CTREE_PARTIAL; + oca.flags = OPEN_CTREE_WRITES | OPEN_CTREE_PARTIAL | OPEN_CTREE_EXCLUSIVE; fs_info = open_ctree_fs_info(&oca); if (!fs_info) { error("could not open btrfs"); @@ -437,7 +437,7 @@ static int cmd_rescue_clear_ino_cache(const struct cmd_struct *cmd, goto out; } oca.filename = devname; - oca.flags = OPEN_CTREE_WRITES; + oca.flags = OPEN_CTREE_WRITES | OPEN_CTREE_EXCLUSIVE; fs_info = open_ctree_fs_info(&oca); if (!fs_info) { error("could not open btrfs"); diff --git a/common/filesystem-utils.c b/common/filesystem-utils.c index 7e898a3d..05451093 100644 --- a/common/filesystem-utils.c +++ b/common/filesystem-utils.c @@ -94,7 +94,8 @@ static int set_label_unmounted(const char *dev, const char *label) /* Open the super_block at the default location * and as read-write. */ - root = open_ctree(dev, 0, OPEN_CTREE_WRITES); + root = open_ctree(dev, 0, OPEN_CTREE_WRITES | + OPEN_CTREE_EXCLUSIVE); if (!root) /* errors are printed by open_ctree() */ return -1; diff --git a/convert/main.c b/convert/main.c index aa253781..b2cfbcef 100644 --- a/convert/main.c +++ b/convert/main.c @@ -1373,7 +1373,8 @@ static int do_convert(const char *devname, u32 convert_flags, u32 nodesize, btrfs_sb_committed = true; root = open_ctree_fd(fd, devname, 0, - OPEN_CTREE_WRITES | OPEN_CTREE_TEMPORARY_SUPER); + OPEN_CTREE_WRITES | OPEN_CTREE_TEMPORARY_SUPER | + OPEN_CTREE_EXCLUSIVE); if (!root) { error("unable to open ctree for finalization"); goto fail; diff --git a/image/image-restore.c b/image/image-restore.c index bed5e78d..667b9811 100644 --- a/image/image-restore.c +++ b/image/image-restore.c @@ -1790,7 +1790,8 @@ int restore_metadump(const char *input, FILE *out, int old_restore, oca.filename = target; oca.flags = OPEN_CTREE_WRITES | OPEN_CTREE_RESTORE | - OPEN_CTREE_PARTIAL | OPEN_CTREE_SKIP_LEAF_ITEM_CHECKS; + OPEN_CTREE_PARTIAL | OPEN_CTREE_SKIP_LEAF_ITEM_CHECKS | + OPEN_CTREE_EXCLUSIVE; info = open_ctree_fs_info(&oca); if (!info) { error("open ctree failed"); @@ -1855,6 +1856,7 @@ int restore_metadump(const char *input, FILE *out, int old_restore, root = open_ctree_fd(fileno(out), target, 0, OPEN_CTREE_PARTIAL | OPEN_CTREE_WRITES | + OPEN_CTREE_EXCLUSIVE | OPEN_CTREE_NO_DEVICES | OPEN_CTREE_ALLOW_TRANSID_MISMATCH | OPEN_CTREE_SKIP_LEAF_ITEM_CHECKS); diff --git a/mkfs/main.c b/mkfs/main.c index b24b148d..3767d032 100644 --- a/mkfs/main.c +++ b/mkfs/main.c @@ -1666,7 +1666,8 @@ int BOX_MAIN(mkfs)(int argc, char **argv) } oca.filename = file; - oca.flags = OPEN_CTREE_WRITES | OPEN_CTREE_TEMPORARY_SUPER; + oca.flags = OPEN_CTREE_WRITES | OPEN_CTREE_TEMPORARY_SUPER | + OPEN_CTREE_EXCLUSIVE; fs_info = open_ctree_fs_info(&oca); if (!fs_info) { error("open ctree failed"); diff --git a/tune/main.c b/tune/main.c index b0509cf1..d246b970 100644 --- a/tune/main.c +++ b/tune/main.c @@ -185,7 +185,7 @@ int BOX_MAIN(btrfstune)(int argc, char *argv[]) { struct btrfs_root *root; struct btrfs_fs_info *fs_info; - unsigned ctree_flags = OPEN_CTREE_WRITES; + unsigned ctree_flags = OPEN_CTREE_WRITES | OPEN_CTREE_EXCLUSIVE; int seeding_flag = 0; u64 seeding_value = 0; int random_fsid = 0;