Re: [PATCH v3] btrfs-progs: fix btrfs resize failed.

[Qu Wenruo <quwenruo.btrfs@gmx.com>]

On 2022/7/26 09:38, li zhang wrote:
> Sorry, I'm a little confused, does the SOB line mean the "--" line?

SOB = Signed-of-by line.

The correct example for that tag for btrfs-progs can be found here:

https://lore.kernel.org/linux-btrfs/20220114005123.19426-4-wqu@suse.com/

Thanks,
Qu

>
> Thanks,
> Li
>
> Qu Wenruo <quwenruo.btrfs@gmx.com> 于2022年7月25日周一 08:34写道：
>>
>>
>>
>> On 2022/7/24 20:43, Li Zhang wrote:
>>> related issuse:
>>> https://github.com/kdave/btrfs-progs/issues/470
>>
>> Something I forgot to mention is related to the changelog part.
>>
>> This can be replaced by the following tag before SOB line:
>>
>> Issue: 470
>>
>>>
>>> V1 link:
>>> https://www.spinics.net/lists/linux-btrfs/msg126661.html
>>>
>>> V2 link:
>>> https://www.spinics.net/lists/linux-btrfs/msg126853.html
>>
>> Changelog for single patch can be put after all the tags, and with a
>> line of "---", so at apply time git will discard the extra info.
>>
>> One example can be found here:
>>
>> https://lore.kernel.org/linux-btrfs/20220617151133.GO20633@twin.jikos.cz/T/
>>
>>>
>>> [BUG]
>>> 1. If there is no devid=1, when the user uses the btrfs file system tool,
>>> the following error will be reported,
>>>
>>> $ sudo btrfs filesystem show /mnt/1
>>> Label: none  uuid: 64dc0f68-9afa-4465-9ea1-2bbebfdb6cec
>>>       Total devices 2 FS bytes used 704.00KiB
>>>       devid    2 size 15.00GiB used 1.16GiB path /dev/loop2
>>>       devid    3 size 15.00GiB used 1.16GiB path /dev/loop3
>>> $ sudo btrfs filesystem resize -1G /mnt/1
>>> ERROR: cannot find devid: 1
>>> ERROR: unable to resize '/mnt/1': No such device
>>>
>>> 2. Function check_resize_args, if get_fs_info is successful,
>>> check_resize_args always returns 0, Even if the parameter
>>> passed to kernel space is longer than the size allowed to
>>> be passed to kernel space (BTRFS_VOL_NAME_MAX).
>>>
>>> [CAUSE]
>>> 1. If the user does not specify the devid id explicitly,
>>> btrfs will use the default devid 1, so it will report an error when dev 1 is missing.
>>>
>>> 2. The last line of the function check_resize_args is return 0.
>>>
>>> [FIX]
>>> 1. If the file system contains multiple devices, output an error message to the user.
>>> If the filesystem has only one device, resize should automatically add the unique devid.
>>>
>>> 2. The function check_resize_args should not return 0 on the last line,
>>> it should return ret representing the return value.
>>>
>>> 3. Update the "btrfs-filesystem" man page
>>>
>>> [RESULT]
>>>
>>> $ sudo btrfs filesystem resize --help
>>> usage: btrfs filesystem resize [options] [devid:][+/-]<newsize>[kKmMgGtTpPeE]|[devid:]max <path>
>>>
>>>       Resize a filesystem
>>>
>>>       If the filesystem contains only one device, devid can be ignored.
>>>       If 'max' is passed, the filesystem will occupy all available space
>>>       on the device 'devid'.
>>>       [kK] means KiB, which denotes 1KiB = 1024B, 1MiB = 1024KiB, etc.
>>>
>>>       --enqueue         wait if there's another exclusive operation running,
>>>                         otherwise continue
>>
>> Although help string is updated, the manpage is still not updated.
>>
>> Thanks,
>> Qu
>>
>>>
>>> $ sudo btrfs filesystem show /mnt/1/
>>> Label: none  uuid: 2025e6ae-0b6d-40b4-8685-3e7e9fc9b2c2
>>>           Total devices 2 FS bytes used 144.00KiB
>>>           devid    2 size 15.00GiB used 1.16GiB path /dev/loop2
>>>           devid    3 size 15.00GiB used 1.16GiB path /dev/loop3
>>>
>>> $ sudo btrfs filesystem resize -1G /mnt/1
>>> ERROR: The file system has multiple devices, please specify devid exactly.
>>> ERROR: The device information list is as follows.
>>>           devid    2 size 15.00GiB used 1.16GiB path /dev/loop2
>>>           devid    3 size 15.00GiB used 1.16GiB path /dev/loop3
>>>
>>> $ sudo btrfs device delete 2 /mnt/1/
>>>
>>> $ sudo btrfs filesystem show /mnt/1/
>>> Label: none  uuid: 2025e6ae-0b6d-40b4-8685-3e7e9fc9b2c2
>>>           Total devices 1 FS bytes used 144.00KiB
>>>           devid    3 size 15.00GiB used 1.28GiB path /dev/loop3
>>>
>>> $ sudo btrfs filesystem resize -1G /mnt/1
>>> Resize device id 3 (/dev/loop3) from 15.00GiB to 14.00GiB
>>>
>>> $ sudo btrfs filesystem show /mnt/1/
>>> Label: none  uuid: cc6e1beb-255b-431f-baf5-02e8056fd0b6
>>>        Total devices 1 FS bytes used 144.00KiB
>>>        devid    3 size 14.00GiB used 1.28GiB path /dev/loop3
>>>
>>> Signed-off-by: Li Zhang <zhanglikernel@gmail.com>
>>> ---
>>>    cmds/filesystem.c | 47 ++++++++++++++++++++++++++++++++++++++++-------
>>>    1 file changed, 40 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/cmds/filesystem.c b/cmds/filesystem.c
>>> index 7cd08fc..e641fcb 100644
>>> --- a/cmds/filesystem.c
>>> +++ b/cmds/filesystem.c
>>> @@ -1078,6 +1078,7 @@ static DEFINE_SIMPLE_COMMAND(filesystem_defrag, "defragment");
>>>    static const char * const cmd_filesystem_resize_usage[] = {
>>>        "btrfs filesystem resize [options] [devid:][+/-]<newsize>[kKmMgGtTpPeE]|[devid:]max <path>",
>>>        "Resize a filesystem",
>>> +     "If the filesystem contains only one device, devid can be ignored.",
>>>        "If 'max' is passed, the filesystem will occupy all available space",
>>>        "on the device 'devid'.",
>>>        "[kK] means KiB, which denotes 1KiB = 1024B, 1MiB = 1024KiB, etc.",
>>> @@ -1087,7 +1088,8 @@ static const char * const cmd_filesystem_resize_usage[] = {
>>>        NULL
>>>    };
>>>
>>> -static int check_resize_args(const char *amount, const char *path) {
>>> +static int check_resize_args(char * const amount, const char *path)
>>> +{
>>>        struct btrfs_ioctl_fs_info_args fi_args;
>>>        struct btrfs_ioctl_dev_info_args *di_args = NULL;
>>>        int ret, i, dev_idx = -1;
>>> @@ -1112,11 +1114,14 @@ static int check_resize_args(const char *amount, const char *path) {
>>>        }
>>>
>>>        ret = snprintf(amount_dup, BTRFS_VOL_NAME_MAX, "%s", amount);
>>> +check:
>>>        if (strlen(amount) != ret) {
>>>                error("newsize argument is too long");
>>>                ret = 1;
>>>                goto out;
>>>        }
>>> +     if (strcmp(amount, amount_dup) != 0)
>>> +             strcpy(amount, amount_dup);
>>>
>>>        sizestr = amount_dup;
>>>        devstr = strchr(sizestr, ':');
>>> @@ -1133,6 +1138,24 @@ static int check_resize_args(const char *amount, const char *path) {
>>>                        ret = 1;
>>>                        goto out;
>>>                }
>>> +     } else if (fi_args.num_devices != 1) {
>>> +             error("The file system has multiple devices, please specify devid exactly.");
>>> +             error("The device information list is as follows.");
>>> +             for (i = 0; i < fi_args.num_devices; i++) {
>>> +                     fprintf(stderr, "\tdevid %4llu size %s used %s path %s\n",
>>> +                             di_args[i].devid,
>>> +                             pretty_size_mode(di_args[i].total_bytes, UNITS_DEFAULT),
>>> +                             pretty_size_mode(di_args[i].bytes_used, UNITS_DEFAULT),
>>> +                             di_args[i].path);
>>> +             }
>>> +             ret = 1;
>>> +             goto out;
>>> +     } else {
>>> +             memset(amount_dup, 0, BTRFS_VOL_NAME_MAX);
>>> +             ret = snprintf(amount_dup, BTRFS_VOL_NAME_MAX, "%llu:", di_args[0].devid);
>>> +             ret = snprintf(amount_dup + strlen(amount_dup),
>>> +                     BTRFS_VOL_NAME_MAX - strlen(amount_dup), "%s", amount);
>>> +             goto check;
>>>        }
>>>
>>>        dev_idx = -1;
>>> @@ -1200,10 +1223,11 @@ static int check_resize_args(const char *amount, const char *path) {
>>>                di_args[dev_idx].path,
>>>                pretty_size_mode(di_args[dev_idx].total_bytes, UNITS_DEFAULT),
>>>                res_str);
>>> +     ret = 0;
>>>
>>>    out:
>>>        free(di_args);
>>> -     return 0;
>>> +     return ret;
>>>    }
>>>
>>>    static int cmd_filesystem_resize(const struct cmd_struct *cmd,
>>> @@ -1213,7 +1237,7 @@ static int cmd_filesystem_resize(const struct cmd_struct *cmd,
>>>        int     fd, res, len, e;
>>>        char    *amount, *path;
>>>        DIR     *dirstream = NULL;
>>> -     int ret;
>>> +     int ret = 0;
>>>        bool enqueue = false;
>>>        bool cancel = false;
>>>
>>> @@ -1277,10 +1301,17 @@ static int cmd_filesystem_resize(const struct cmd_struct *cmd,
>>>                }
>>>        }
>>>
>>> +     amount = (char *)malloc(BTRFS_VOL_NAME_MAX);
>>> +     if (!amount)
>>> +             return -ENOMEM;
>>> +
>>> +     strcpy(amount, argv[optind]);
>>> +
>>>        ret = check_resize_args(amount, path);
>>>        if (ret != 0) {
>>>                close_file_or_dir(fd, dirstream);
>>> -             return 1;
>>> +             ret = 1;
>>> +             goto free_amount;
>>>        }
>>>
>>>        memset(&args, 0, sizeof(args));
>>> @@ -1298,7 +1329,7 @@ static int cmd_filesystem_resize(const struct cmd_struct *cmd,
>>>                        error("unable to resize '%s': %m", path);
>>>                        break;
>>>                }
>>> -             return 1;
>>> +             ret = 1;
>>>        } else if (res > 0) {
>>>                const char *err_str = btrfs_err_str(res);
>>>
>>> @@ -1308,9 +1339,11 @@ static int cmd_filesystem_resize(const struct cmd_struct *cmd,
>>>                        error("resizing of '%s' failed: unknown error %d",
>>>                                path, res);
>>>                }
>>> -             return 1;
>>> +             ret = 1;
>>>        }
>>> -     return 0;
>>> +free_amount:
>>> +     free(amount);
>>> +     return ret;
>>>    }
>>>    static DEFINE_SIMPLE_COMMAND(filesystem_resize, "resize");
>>>