/* * RAID-6 data recovery in dual failure mode based on the XC instruction. * * Copyright IBM Corp. 2016 * Author(s): Martin Schwidefsky */ #include #include static inline void xor_block(u8 *p1, u8 *p2) { typedef struct { u8 _[256]; } addrtype; asm volatile( " xc 0(256,%[p1]),0(%[p2])\n" : "+m" (*(addrtype *) p1) : "m" (*(addrtype *) p2), [p1] "a" (p1), [p2] "a" (p2) : "cc"); } /* Recover two failed data blocks. */ static void raid6_2data_recov_s390xc(int disks, size_t bytes, int faila, int failb, void **ptrs) { u8 *p, *q, *dp, *dq; const u8 *pbmul; /* P multiplier table for B data */ const u8 *qmul; /* Q multiplier table (for both) */ int i; p = (u8 *)ptrs[disks-2]; q = (u8 *)ptrs[disks-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 *)ptrs[faila]; ptrs[faila] = (void *)raid6_empty_zero_page; ptrs[disks-2] = dp; dq = (u8 *)ptrs[failb]; ptrs[failb] = (void *)raid6_empty_zero_page; ptrs[disks-1] = dq; raid6_call.gen_syndrome(disks, bytes, ptrs); /* Restore pointer table */ ptrs[faila] = dp; ptrs[failb] = dq; ptrs[disks-2] = p; ptrs[disks-1] = q; /* Now, pick the proper data tables */ pbmul = raid6_gfmul[raid6_gfexi[failb-faila]]; qmul = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]]; /* Now do it... */ while (bytes) { xor_block(dp, p); xor_block(dq, q); for (i = 0; i < 256; i++) dq[i] = pbmul[dp[i]] ^ qmul[dq[i]]; xor_block(dp, dq); p += 256; q += 256; dp += 256; dq += 256; bytes -= 256; } } /* Recover failure of one data block plus the P block */ static void raid6_datap_recov_s390xc(int disks, size_t bytes, int faila, void **ptrs) { u8 *p, *q, *dq; const u8 *qmul; /* Q multiplier table */ int i; p = (u8 *)ptrs[disks-2]; q = (u8 *)ptrs[disks-1]; /* Compute syndrome with zero for the missing data page Use the dead data page as temporary storage for delta q */ dq = (u8 *)ptrs[faila]; ptrs[faila] = (void *)raid6_empty_zero_page; ptrs[disks-1] = dq; raid6_call.gen_syndrome(disks, bytes, ptrs); /* Restore pointer table */ ptrs[faila] = dq; ptrs[disks-1] = q; /* Now, pick the proper data tables */ qmul = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]]]; /* Now do it... */ while (bytes) { xor_block(dq, q); for (i = 0; i < 256; i++) dq[i] = qmul[dq[i]]; xor_block(p, dq); p += 256; q += 256; dq += 256; bytes -= 256; } } const struct raid6_recov_calls raid6_recov_s390xc = { .data2 = raid6_2data_recov_s390xc, .datap = raid6_datap_recov_s390xc, .valid = NULL, .name = "s390xc", .priority = 1, }; 'txt' type='search' size='10' name='q' value=''/>
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authorChristoph Hellwig <hch@lst.de>2017-01-30 13:15:41 +0100
committerBjorn Helgaas <bhelgaas@google.com>2017-02-02 10:35:46 -0600
commitdfef358bd1beb4e7b5c94eca944be9cd23dfc752 (patch)
treeb9a2afb38a4c2ac8ad31f49ec0d71fe9e5b1994c /net/bridge/br.c
parent030305d69fc6963c16003f50d7e8d74b02d0a143 (diff)
PCI/MSI: Don't apply affinity if there aren't enough vectors left
Bart reported a problem wіth an out of bounds access in the low-level IRQ affinity code, which we root caused to the qla2xxx driver assigning all its MSI-X vectors to the pre and post vectors, and not having any left for the actually spread IRQs. Fix this issue by not asking for affinity assignment when there are no vectors to assign left. Fixes: 402723ad5c62 ("PCI/MSI: Provide pci_alloc_irq_vectors_affinity()") Link: https://lkml.kernel.org/r/1485359225.3093.3.camel@sandisk.com Reported-by: Bart Van Assche <bart.vanassche@sandisk.com> Tested-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'net/bridge/br.c')