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Message-ID: <61C27A0E.9050900@huawei.com> Date: Wed, 22 Dec 2021 09:06:22 +0800 From: yebin <yebin10@...wei.com> To: Lukas Czerner <lczerner@...hat.com> CC: <tytso@....edu>, <adilger.kernel@...ger.ca>, <linux-ext4@...r.kernel.org>, <linux-kernel@...r.kernel.org>, <jack@...e.cz> Subject: Re: [PATCH -next] ext4: Fix remount with 'abort' option isn't effective On 2021/12/21 22:43, Lukas Czerner wrote: > Hi, > > nice catch. This is a bug indeed. However I am currently in a process of > changing the ctx_set/clear/test_ helpers because currently it generates > functions that are unused. > > While I am at it I can just create a custom ctx_set_mount_flags() > helper that would behave as expected so that we won't have to specify > "1 < EXT4_MF_FS_ABORTED" which is not really obvious and hence error > prone. Actually, I fixed the first version as follows: diff --git a/fs/ext4/super.c b/fs/ext4/super.c index b72d989b77fb..199920ffc7d3 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2049,8 +2049,8 @@ struct ext4_fs_context { unsigned int mask_s_mount_opt; unsigned int vals_s_mount_opt2; unsigned int mask_s_mount_opt2; - unsigned int vals_s_mount_flags; - unsigned int mask_s_mount_flags; + unsigned long vals_s_mount_flags; + unsigned long mask_s_mount_flags; unsigned int opt_flags; /* MOPT flags */ unsigned int spec; u32 s_max_batch_time; @@ -2166,7 +2166,12 @@ static inline bool ctx_test_##name(struct ext4_fs_context *ctx, int flag)\ EXT4_SET_CTX(flags); EXT4_SET_CTX(mount_opt); EXT4_SET_CTX(mount_opt2); -EXT4_SET_CTX(mount_flags); + +static inline void ctx_set_mount_flags(struct ext4_fs_context *ctx, int bit) +{ + set_bit(bit, &ctx->mask_s_mount_flags); + set_bit(bit, &ctx->vals_s_mount_flags); +} I think 'mask_s_mount_flags' is useless now. > > My plan is to send my patch set including this one tomorrow, will that > be fine with you ? > > -Lukas > > On Tue, Dec 21, 2021 at 08:32:14PM +0800, Ye Bin wrote: >> We test remount with 'abort' option as follows: >> [root@...alhost home]# mount /dev/sda test >> [root@...alhost home]# mount | grep test >> /dev/sda on /home/test type ext4 (rw,relatime) >> [root@...alhost home]# mount -o remount,abort test >> [root@...alhost home]# mount | grep test >> /dev/sda on /home/test type ext4 (rw,relatime) >> >> Obviously, remount 'abort' option isn't effective. >> After 6e47a3cc68fc commit we process abort option with 'ctx_set_mount_flags': >> static inline void ctx_set_mount_flags(struct ext4_fs_context *ctx, int flag) >> { >> ctx->mask_s_mount_flags |= flag; >> ctx->vals_s_mount_flags |= flag; >> } >> >> But we test 'abort' option with 'ext4_test_mount_flag': >> static inline int ext4_test_mount_flag(struct super_block *sb, int bit) >> { >> return test_bit(bit, &EXT4_SB(sb)->s_mount_flags); >> } >> >> To solve this issue, pass (1 << EXT4_MF_FS_ABORTED) to 'ctx_set_mount_flags'. >> >> Fixes:6e47a3cc68fc("ext4: get rid of super block and sbi from handle_mount_ops()") >> Signed-off-by: Ye Bin <yebin10@...wei.com> >> --- >> fs/ext4/super.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/fs/ext4/super.c b/fs/ext4/super.c >> index b72d989b77fb..071b7b3c5678 100644 >> --- a/fs/ext4/super.c >> +++ b/fs/ext4/super.c >> @@ -2236,7 +2236,7 @@ static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param) >> param->key); >> return 0; >> case Opt_abort: >> - ctx_set_mount_flags(ctx, EXT4_MF_FS_ABORTED); >> + ctx_set_mount_flags(ctx, 1 << EXT4_MF_FS_ABORTED); >> return 0; >> case Opt_i_version: >> ctx_set_flags(ctx, SB_I_VERSION); >> -- >> 2.31.1 >> > . >
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