On Wed, Sep 19, 2018 at 08:40:38PM +0200, Goffredo Baroncelli wrote: > From: Goffredo Baroncelli <kreij...@inwind.it> > > Add support for recovery for a RAID 5 btrfs profile. In addition > it is added some code as preparatory work for RAID 6 recovery code. > > Signed-off-by: Goffredo Baroncelli <kreij...@inwind.it> > --- > grub-core/fs/btrfs.c | 169 +++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 164 insertions(+), 5 deletions(-) > > diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c > index 5c1ebae77..55a7eeffc 100644 > --- a/grub-core/fs/btrfs.c > +++ b/grub-core/fs/btrfs.c > @@ -29,6 +29,7 @@ > #include <minilzo.h> > #include <grub/i18n.h> > #include <grub/btrfs.h> > +#include <grub/crypto.h> > > GRUB_MOD_LICENSE ("GPLv3+"); > > @@ -665,6 +666,148 @@ btrfs_read_from_chunk (struct grub_btrfs_data *data, > return err; > } > > +struct raid56_buffer { > + void *buf; > + int data_is_valid; > +}; > + > +static void > +rebuild_raid5 (char *dest, struct raid56_buffer *buffers, > + grub_uint64_t nstripes, grub_uint64_t csize) > +{ > + grub_uint64_t i; > + int first; > + > + i = 0; > + while (buffers[i].data_is_valid && i < nstripes) > + ++i;
for (i = 0; buffers[i].data_is_valid && i < nstripes; i++); > + if (i == nstripes) > + { > + grub_dprintf ("btrfs", "called rebuild_raid5(), but all disks are > OK\n"); > + return; > + } > + > + grub_dprintf ("btrfs", "rebuilding RAID 5 stripe #%" PRIuGRUB_UINT64_T > "\n", > + i); One line here please. > + for (i = 0, first = 1; i < nstripes; i++) > + { > + if (!buffers[i].data_is_valid) > + continue; > + > + if (first) { > + grub_memcpy(dest, buffers[i].buf, csize); > + first = 0; > + } else > + grub_crypto_xor (dest, dest, buffers[i].buf, csize); > + > + } Hmmm... I think that this function can be simpler. You can drop first while/for and "if (i == nstripes)". Then here: if (first) { grub_dprintf ("btrfs", "called rebuild_raid5(), but all disks are OK\n"); Am I right? > +} > + > +static grub_err_t > +raid56_read_retry (struct grub_btrfs_data *data, > + struct grub_btrfs_chunk_item *chunk, > + grub_uint64_t stripe_offset, > + grub_uint64_t csize, void *buf) > +{ > + struct raid56_buffer *buffers; > + grub_uint64_t nstripes = grub_le_to_cpu16 (chunk->nstripes); > + grub_uint64_t chunk_type = grub_le_to_cpu64 (chunk->type); > + grub_err_t ret = GRUB_ERR_NONE; s/GRUB_ERR_NONE/GRUB_ERR_OUT_OF_MEMORY/ and then you can drop at least two relevant assigments and some curly brackets. Of course before cleanup label you have to add ret = GRUB_ERR_NONE. > + grub_uint64_t i, failed_devices; > + > + buffers = grub_zalloc (sizeof(*buffers) * nstripes); > + if (!buffers) > + { > + ret = GRUB_ERR_OUT_OF_MEMORY; > + goto cleanup; > + } > + > + for (i = 0; i < nstripes; i++) > + { > + buffers[i].buf = grub_zalloc (csize); > + if (!buffers[i].buf) > + { > + ret = GRUB_ERR_OUT_OF_MEMORY; > + goto cleanup; > + } > + } > + > + for (failed_devices = 0, i = 0; i < nstripes; i++) > + { > + struct grub_btrfs_chunk_stripe *stripe; > + grub_disk_addr_t paddr; > + grub_device_t dev; > + grub_err_t err2; s/err2/err/? > + > + stripe = (struct grub_btrfs_chunk_stripe *) (chunk + 1); > + stripe += i; Why not stripe = ((struct grub_btrfs_chunk_stripe *) (chunk + 1)) + i;? Daniel