On Dez 30 2022, Qu Wenruo wrote: > [BUG] > Since btrfs supports single device RAID0 at mkfs time after btrfs-progs > v5.14, if we create a single device raid0 btrfs, and created a file > crossing stripe boundary: > > # mkfs.btrfs -m dup -d raid0 test.img > # mount test.img mnt > # xfs_io -f -c "pwrite 0 128K" mnt/file > # umount mnt > > Since btrfs is using 64K as stripe length, above 128K data write is > definitely going to cross at least one stripe boundary. > > Then u-boot would fail to read above 128K file: > > => host bind 0 /home/adam/test.img > => ls host 0 > < > 131072 Fri Dec 30 00:18:25 2022 file > => load host 0 0 file > BTRFS: An error occurred while reading file file > Failed to load 'file' > > [CAUSE] > Unlike tree blocks read, data extent reads doesn't consider cases in which > one data extent can cross stripe boundary. > > In read_data_extent(), we just call btrfs_map_block() once and read the > first mapped range. > > And if the first mapped range is smaller than the desired range, it > would return error. > > But since even single device btrfs can utilize RAID0 profiles, the first > mapped range can only be at most 64K for RAID0 profiles, and cause false > error. > > [FIX] > Just like read_whole_eb(), we should call btrfs_map_block() in a loop > until we read all data. > > Since we're here, also add extra error messages for the following cases: > > - btrfs_map_block() failure > We already have the error message for it. > > - Missing device > This should not happen, as we only support single device for now. > > - __btrfs_devread() failure > > With this bug fixed, btrfs driver of u-boot can properly read the above > 128K file, and have the correct content: > > => host bind 0 /home/adam/test.img > => ls host 0 > < > 131072 Fri Dec 30 00:18:25 2022 file > => load host 0 0 file > 131072 bytes read in 0 ms > => md5sum 0 0x20000 > md5 for 00000000 ... 0001ffff ==> d48858312a922db7eb86377f638dbc9f > ^^^ Above md5sum also matches. > > Reported-by: Sam Winchenbach <swichenb...@tethers.com> > Signed-off-by: Qu Wenruo <w...@suse.com>
This breaks btrfs on the HiFive Unmatched. => pci enum PCIE-0: Link up (Gen1-x8, Bus0) => nvme scan => load nvme 0:2 0x8c000000 /boot/dtb/sifive/hifive-unmatched-a00.dtb [hangs] -- Andreas Schwab, sch...@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."
