@@ -92,10 +92,10 @@ CHECKER_FLAGS := -include $(check_defs) -D__CHECKER__ \
objects = ctree.o disk-io.o kernel-lib/radix-tree.o extent-tree.o print-tree.o \
root-tree.o dir-item.o file-item.o inode-item.o inode-map.o \
extent-cache.o extent_io.o volumes.o utils.o repair.o \
- qgroup.o raid56.o free-space-cache.o kernel-lib/list_sort.o props.o \
+ qgroup.o free-space-cache.o kernel-lib/list_sort.o props.o \
kernel-shared/ulist.o qgroup-verify.o backref.o string-table.o task-utils.o \
inode.o file.o find-root.o free-space-tree.o help.o send-dump.o \
- fsfeatures.o kernel-lib/tables.o
+ fsfeatures.o kernel-lib/tables.o kernel-lib/raid56.o
cmds_objects = cmds-subvolume.o cmds-filesystem.o cmds-device.o cmds-scrub.o \
cmds-inspect.o cmds-balance.o cmds-send.o cmds-receive.o \
cmds-quota.o cmds-qgroup.o cmds-replace.o cmds-check.o \
similarity index 71%
rename from raid56.c
rename to kernel-lib/raid56.c
@@ -28,6 +28,7 @@
#include "disk-io.h"
#include "volumes.h"
#include "utils.h"
+#include "kernel-lib/raid56.h"
/*
* This is the C data type to use
@@ -170,3 +171,71 @@ int raid5_gen_result(int nr_devs, size_t stripe_len, int dest, void **data)
}
return 0;
}
+
+/*
+ * Raid 6 recovery code copied from kernel lib/raid6/recov.c.
+ * With modifications:
+ * - rename from raid6_2data_recov_intx1
+ * - kfree/free modification for btrfs-progs
+ */
+int raid6_recov_data2(int nr_devs, size_t stripe_len, int dest1, int dest2,
+ void **data)
+{
+ u8 *p, *q, *dp, *dq;
+ u8 px, qx, db;
+ const u8 *pbmul; /* P multiplier table for B data */
+ const u8 *qmul; /* Q multiplier table (for both) */
+ char *zero_mem1, *zero_mem2;
+ int ret = 0;
+
+ /* Early check */
+ if (dest1 < 0 || dest1 >= nr_devs - 2 ||
+ dest2 < 0 || dest2 >= nr_devs - 2 || dest1 >= dest2)
+ return -EINVAL;
+
+ zero_mem1 = calloc(1, stripe_len);
+ zero_mem2 = calloc(1, stripe_len);
+ if (!zero_mem1 || !zero_mem2) {
+ free(zero_mem1);
+ free(zero_mem2);
+ return -ENOMEM;
+ }
+
+ p = (u8 *)data[nr_devs - 2];
+ q = (u8 *)data[nr_devs - 1];
+
+ /* Compute syndrome with zero for the missing data pages
+ Use the dead data pages as temporary storage for
+ delta p and delta q */
+ dp = (u8 *)data[dest1];
+ data[dest1] = (void *)zero_mem1;
+ data[nr_devs - 2] = dp;
+ dq = (u8 *)data[dest2];
+ data[dest2] = (void *)zero_mem2;
+ data[nr_devs - 1] = dq;
+
+ raid6_gen_syndrome(nr_devs, stripe_len, data);
+
+ /* Restore pointer table */
+ data[dest1] = dp;
+ data[dest2] = dq;
+ data[nr_devs - 2] = p;
+ data[nr_devs - 1] = q;
+
+ /* Now, pick the proper data tables */
+ pbmul = raid6_gfmul[raid6_gfexi[dest2 - dest1]];
+ qmul = raid6_gfmul[raid6_gfinv[raid6_gfexp[dest1]^raid6_gfexp[dest2]]];
+
+ /* Now do it... */
+ while ( stripe_len-- ) {
+ px = *p ^ *dp;
+ qx = qmul[*q ^ *dq];
+ *dq++ = db = pbmul[px] ^ qx; /* Reconstructed B */
+ *dp++ = db ^ px; /* Reconstructed A */
+ p++; q++;
+ }
+
+ free(zero_mem1);
+ free(zero_mem2);
+ return ret;
+}
@@ -37,4 +37,9 @@ extern const u8 raid6_vgfmul[256][32] __attribute__((aligned(256)));
extern const u8 raid6_gfexp[256] __attribute__((aligned(256)));
extern const u8 raid6_gfinv[256] __attribute__((aligned(256)));
extern const u8 raid6_gfexi[256] __attribute__((aligned(256)));
+
+
+/* Recover raid6 with 2 data corrupted */
+int raid6_recov_data2(int nr_devs, size_t stripe_len, int dest1, int dest2,
+ void **data);
#endif
Copied from kernel lib/raid6/recov.c raid6_2data_recov_intx1() function. With the following modification: - Rename to raid6_recov_data2() for shorter name - s/kfree/free/g modification Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> --- Makefile | 4 +-- raid56.c => kernel-lib/raid56.c | 69 +++++++++++++++++++++++++++++++++++++++++ kernel-lib/raid56.h | 5 +++ 3 files changed, 76 insertions(+), 2 deletions(-) rename raid56.c => kernel-lib/raid56.c (71%)