[PATCH v2 0/1] expand-on-first-boot: Check size before resizing

[PATCH v2 0/1] expand-on-first-boot: Check size before resizing

[Tobias Schmidl]

Diff to v1:
- Reduced console output

Tobias Schmidl (1):
  expand-on-first-boot: Check size before resizing

 .../files/expand-last-partition.sh               | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

-- 
2.36.1

[PATCH v2 1/1] expand-on-first-boot: Check size before resizing

[Tobias Schmidl]

If the disk is too small, resizing might have detrimental effects.
Because of aligning issues, it could happen the the final partition is
_smaller_ than desired, which might lead to an unusable last partition.

Signed-off-by: Tobias Schmidl <tobiasschmidl@siemens.com>
---
 .../files/expand-last-partition.sh               | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh b/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
index c0edde7..0aa1063 100755
--- a/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
+++ b/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
@@ -22,6 +22,22 @@ if [ "${ROOT_DEV}" = "${BOOT_DEV}" ]; then
 	exit 1
 fi
 
+# this value is in blocks. Normally a block has 512 bytes.
+BUFFER_SIZE=32768
+BOOT_DEV_NAME=${BOOT_DEV##*/}
+DISK_SIZE="$(cat /sys/class/block/"${BOOT_DEV_NAME}"/size)"
+ALL_PARTS_SIZE=0
+for PARTITION in /sys/class/block/"${BOOT_DEV_NAME}"[1-9]*; do
+	PART_SIZE=$(cat "${PARTITION}"/size)
+	ALL_PARTS_SIZE=$((ALL_PARTS_SIZE + PART_SIZE))
+done
+
+MINIMAL_SIZE=$((ALL_PARTS_SIZE + BUFFER_SIZE))
+if [ "$DISK_SIZE" -lt "$MINIMAL_SIZE" ]; then
+	echo "Disk is practically already full, doing nothing." >&2
+	exit 0
+fi
+
 LAST_PART="$(sfdisk -d "${BOOT_DEV}" 2>/dev/null | tail -1 | cut -d ' ' -f 1)"
 
 # Transform the partition table as follows:
-- 
2.36.1

Re: [PATCH v2 1/1] expand-on-first-boot: Check size before resizing

[Henning Schild]

LGTM, i also like the idea of asking whether it is worth growing instead
of asking the more complicated question whether we would potentially
shrink trying to grow.

Henning

Am Mon, 11 Jul 2022 10:16:02 +0200
schrieb Tobias Schmidl <tobiasschmidl@siemens.com>:

> If the disk is too small, resizing might have detrimental effects.
> Because of aligning issues, it could happen the the final partition is
> _smaller_ than desired, which might lead to an unusable last
> partition.
> 
> Signed-off-by: Tobias Schmidl <tobiasschmidl@siemens.com>
> ---
>  .../files/expand-last-partition.sh               | 16
> ++++++++++++++++ 1 file changed, 16 insertions(+)
> 
> diff --git
> a/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> b/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> index c0edde7..0aa1063 100755 ---
> a/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> +++
> b/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> @@ -22,6 +22,22 @@ if [ "${ROOT_DEV}" = "${BOOT_DEV}" ]; then exit 1
> fi +# this value is in blocks. Normally a block has 512 bytes.
> +BUFFER_SIZE=32768
> +BOOT_DEV_NAME=${BOOT_DEV##*/}
> +DISK_SIZE="$(cat /sys/class/block/"${BOOT_DEV_NAME}"/size)"
> +ALL_PARTS_SIZE=0
> +for PARTITION in /sys/class/block/"${BOOT_DEV_NAME}"[1-9]*; do
> +	PART_SIZE=$(cat "${PARTITION}"/size)
> +	ALL_PARTS_SIZE=$((ALL_PARTS_SIZE + PART_SIZE))
> +done
> +
> +MINIMAL_SIZE=$((ALL_PARTS_SIZE + BUFFER_SIZE))
> +if [ "$DISK_SIZE" -lt "$MINIMAL_SIZE" ]; then
> +	echo "Disk is practically already full, doing nothing." >&2
> +	exit 0
> +fi
> +
>  LAST_PART="$(sfdisk -d "${BOOT_DEV}" 2>/dev/null | tail -1 | cut -d
> ' ' -f 1)" 
>  # Transform the partition table as follows:

Re: [PATCH v2 1/1] expand-on-first-boot: Check size before resizing

[Uladzimir Bely]

[-- Attachment #1: Type: text/plain, Size: 1878 bytes --]

In the email from Monday, 11 July 2022 11:16:02 +03 user Tobias Schmidl wrote:
> If the disk is too small, resizing might have detrimental effects.
> Because of aligning issues, it could happen the the final partition is
> _smaller_ than desired, which might lead to an unusable last partition.
> 
> Signed-off-by: Tobias Schmidl <tobiasschmidl@siemens.com>
> ---
>  .../files/expand-last-partition.sh               | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git
> a/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> b/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> index c0edde7..0aa1063 100755
> ---
> a/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> +++
> b/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> @@ -22,6 +22,22 @@ if [ "${ROOT_DEV}" = "${BOOT_DEV}" ]; then
>  	exit 1
>  fi
> 
> +# this value is in blocks. Normally a block has 512 bytes.
> +BUFFER_SIZE=32768
> +BOOT_DEV_NAME=${BOOT_DEV##*/}
> +DISK_SIZE="$(cat /sys/class/block/"${BOOT_DEV_NAME}"/size)"
> +ALL_PARTS_SIZE=0
> +for PARTITION in /sys/class/block/"${BOOT_DEV_NAME}"[1-9]*; do

It seems to be working only for something like 'sda' => 'sda1'.

For RPi I have  
root@isar:~# ls /sys/class/block/ | grep mmc 
mmcblk0 
mmcblk0p1 
mmcblk0p2
So, "p" suffix is required.

Some other devices (like nvme) also need some prefix.

> +	PART_SIZE=$(cat "${PARTITION}"/size)
> +	ALL_PARTS_SIZE=$((ALL_PARTS_SIZE + PART_SIZE))
> +done
> +
> +MINIMAL_SIZE=$((ALL_PARTS_SIZE + BUFFER_SIZE))
> +if [ "$DISK_SIZE" -lt "$MINIMAL_SIZE" ]; then
> +	echo "Disk is practically already full, doing nothing." >&2
> +	exit 0
> +fi
> +
>  LAST_PART="$(sfdisk -d "${BOOT_DEV}" 2>/dev/null | tail -1 | cut -d ' ' -f
> 1)"
> 
>  # Transform the partition table as follows:


-- 
Uladzimir Bely


[-- Attachment #2: Type: text/html, Size: 6249 bytes --]

Re: [PATCH v2 1/1] expand-on-first-boot: Check size before resizing

[Uladzimir Bely]

In the email from Monday, 11 July 2022 11:16:02 +03 user Tobias Schmidl wrote:
> If the disk is too small, resizing might have detrimental effects.
> Because of aligning issues, it could happen the the final partition is
> _smaller_ than desired, which might lead to an unusable last partition.
> 
> Signed-off-by: Tobias Schmidl <tobiasschmidl@siemens.com>
> ---
>  .../files/expand-last-partition.sh               | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git
> a/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> b/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> index c0edde7..0aa1063 100755
> ---
> a/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> +++
> b/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
> @@ -22,6 +22,22 @@ if [ "${ROOT_DEV}" = "${BOOT_DEV}" ]; then
>  	exit 1
>  fi
> 
> +# this value is in blocks. Normally a block has 512 bytes.
> +BUFFER_SIZE=32768
> +BOOT_DEV_NAME=${BOOT_DEV##*/}
> +DISK_SIZE="$(cat /sys/class/block/"${BOOT_DEV_NAME}"/size)"
> +ALL_PARTS_SIZE=0
> +for PARTITION in /sys/class/block/"${BOOT_DEV_NAME}"[1-9]*; do

While whole device directory in 'sys/class/block' includes all partitions as 
subfolders, I would change it to

+for PARTITION in /sys/class/block/"${BOOT_DEV_NAME}"/"${BOOT_DEV_NAME}"*; do

It should cover all cases like 'sda/sdaX', 'mmcblk0/mmcblk0pX', 'nvme0/
nvme0pX' and similar.

> +	PART_SIZE=$(cat "${PARTITION}"/size)
> +	ALL_PARTS_SIZE=$((ALL_PARTS_SIZE + PART_SIZE))
> +done
> +
> +MINIMAL_SIZE=$((ALL_PARTS_SIZE + BUFFER_SIZE))
> +if [ "$DISK_SIZE" -lt "$MINIMAL_SIZE" ]; then
> +	echo "Disk is practically already full, doing nothing." >&2
> +	exit 0
> +fi
> +
>  LAST_PART="$(sfdisk -d "${BOOT_DEV}" 2>/dev/null | tail -1 | cut -d ' ' -f
> 1)"
> 
>  # Transform the partition table as follows:


-- 
Uladzimir Bely

Re: [PATCH v2 1/1] expand-on-first-boot: Check size before resizing

[Schmidl, Tobias]

Hi Uladzimir,

Am Mittwoch, dem 13.07.2022 um 11:00 +0300 schrieb Uladzimir Bely:
> 
> While whole device directory in 'sys/class/block' includes all
> partitions as 
> subfolders, I would change it to
> 
> +for PARTITION in
> /sys/class/block/"${BOOT_DEV_NAME}"/"${BOOT_DEV_NAME}"*; do
> 
> It should cover all cases like 'sda/sdaX', 'mmcblk0/mmcblk0pX', 'nvme0/
> nvme0pX' and similar.
> 
> 

thanks for the suggestion, will post the corrected past right after
testing.

Kinds regards,


Tobias

Re: [PATCH v2 0/1] expand-on-first-boot: Check size before resizing

[Schmidl, Tobias]

Hi all,

Am Montag, dem 11.07.2022 um 10:16 +0200 schrieb Tobias Schmidl:
> Diff to v1:
> - Reduced console output
> 
> Tobias Schmidl (1):
>   expand-on-first-boot: Check size before resizing
> 
>  .../files/expand-last-partition.sh               | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 

What is the status of this patch? Are there any impediments?

Kind regards,

Tobias

Re: [PATCH v2 0/1] expand-on-first-boot: Check size before resizing

[Anton Mikanovich]

20.07.2022 15:38, Schmidl, Tobias wrote:
> Hi all,
>
> Am Montag, dem 11.07.2022 um 10:16 +0200 schrieb Tobias Schmidl:
>> Diff to v1:
>> - Reduced console output
>>
>> Tobias Schmidl (1):
>>    expand-on-first-boot: Check size before resizing
>>
>>   .../files/expand-last-partition.sh               | 16 ++++++++++++++++
>>   1 file changed, 16 insertions(+)
>>
> What is the status of this patch? Are there any impediments?
>
> Kind regards,
>
> Tobias
>
Hello Tobias,
This one is superseded. V3 planned to be merged to next tomorrow.