#include #include #include #include #define SG_MEMPOOL_NR ARRAY_SIZE(sg_pools) #define SG_MEMPOOL_SIZE 2 struct sg_pool { size_t size; char *name; struct kmem_cache *slab; mempool_t *pool; }; #define SP(x) { .size = x, "sgpool-" __stringify(x) } #if (SG_CHUNK_SIZE < 32) #error SG_CHUNK_SIZE is too small (must be 32 or greater) #endif static struct sg_pool sg_pools[] = { SP(8), SP(16), #if (SG_CHUNK_SIZE > 32) SP(32), #if (SG_CHUNK_SIZE > 64) SP(64), #if (SG_CHUNK_SIZE > 128) SP(128), #if (SG_CHUNK_SIZE > 256) #error SG_CHUNK_SIZE is too large (256 MAX) #endif #endif #endif #endif SP(SG_CHUNK_SIZE) }; #undef SP static inline unsigned int sg_pool_index(unsigned short nents) { unsigned int index; BUG_ON(nents > SG_CHUNK_SIZE); if (nents <= 8) index = 0; else index = get_count_order(nents) - 3; return index; } static void sg_pool_free(struct scatterlist *sgl, unsigned int nents) { struct sg_pool *sgp; sgp = sg_pools + sg_pool_index(nents); mempool_free(sgl, sgp->pool); } static struct scatterlist *sg_pool_alloc(unsigned int nents, gfp_t gfp_mask) { struct sg_pool *sgp; sgp = sg_pools + sg_pool_index(nents); return mempool_alloc(sgp->pool, gfp_mask); } /** * sg_free_table_chained - Free a previously mapped sg table * @table: The sg table header to use * @first_chunk: was first_chunk not NULL in sg_alloc_table_chained? * * Description: * Free an sg table previously allocated and setup with * sg_alloc_table_chained(). * **/ void sg_free_table_chained(struct sg_table *table, bool first_chunk) { if (first_chunk && table->orig_nents <= SG_CHUNK_SIZE) return; __sg_free_table(table, SG_CHUNK_SIZE, first_chunk, sg_pool_free); } EXPORT_SYMBOL_GPL(sg_free_table_chained); /** * sg_alloc_table_chained - Allocate and chain SGLs in an sg table * @table: The sg table header to use * @nents: Number of entries in sg list * @first_chunk: first SGL * * Description: * Allocate and chain SGLs in an sg table. If @nents@ is larger than * SG_CHUNK_SIZE a chained sg table will be setup. * **/ int sg_alloc_table_chained(struct sg_table *table, int nents, struct scatterlist *first_chunk) { int ret; BUG_ON(!nents); if (first_chunk) { if (nents <= SG_CHUNK_SIZE) { table->nents = table->orig_nents = nents; sg_init_table(table->sgl, nents); return 0; } } ret = __sg_alloc_table(table, nents, SG_CHUNK_SIZE, first_chunk, GFP_ATOMIC, sg_pool_alloc); if (unlikely(ret)) sg_free_table_chained(table, (bool)first_chunk); return ret; } EXPORT_SYMBOL_GPL(sg_alloc_table_chained); static __init int sg_pool_init(void) { int i; for (i = 0; i < SG_MEMPOOL_NR; i++) { struct sg_pool *sgp = sg_pools + i; int size = sgp->size * sizeof(struct scatterlist); sgp->slab = kmem_cache_create(sgp->name, size, 0, SLAB_HWCACHE_ALIGN, NULL); if (!sgp->slab) { printk(KERN_ERR "SG_POOL: can't init sg slab %s\n", sgp->name); goto cleanup_sdb; } sgp->pool = mempool_create_slab_pool(SG_MEMPOOL_SIZE, sgp->slab); if (!sgp->pool) { printk(KERN_ERR "SG_POOL: can't init sg mempool %s\n", sgp->name); goto cleanup_sdb; } } return 0; cleanup_sdb: for (i = 0; i < SG_MEMPOOL_NR; i++) { struct sg_pool *sgp = sg_pools + i; if (sgp->pool) mempool_destroy(sgp->pool); if (sgp->slab) kmem_cache_destroy(sgp->slab); } return -ENOMEM; } static __exit void sg_pool_exit(void) { int i; for (i = 0; i < SG_MEMPOOL_NR; i++) { struct sg_pool *sgp = sg_pools + i; mempool_destroy(sgp->pool); kmem_cache_destroy(sgp->slab); } } module_init(sg_pool_init); module_exit(sg_pool_exit); space:mode:
authorDavid S. Miller <davem@davemloft.net>2017-01-30 14:28:22 -0800
committerDavid S. Miller <davem@davemloft.net>2017-01-30 14:28:22 -0800
commit54791b276b4000b307339f269d3bf7db877d536f (patch)
tree1c2616bd373ce5ea28aac2a53e32f5b5834901ce /tools/build/feature/test-all.c
parent5d0e7705774dd412a465896d08d59a81a345c1e4 (diff)
parent047487241ff59374fded8c477f21453681f5995c (diff)
Merge branch 'sparc64-non-resumable-user-error-recovery'
Liam R. Howlett says: ==================== sparc64: Recover from userspace non-resumable PIO & MEM errors A non-resumable error from userspace is able to cause a kernel panic or trap loop due to the setup and handling of the queued traps once in the kernel. This patch series addresses both of these issues. The queues are fixed by simply zeroing the memory before use. PIO errors from userspace will result in a SIGBUS being sent to the user process. The MEM errors form userspace will result in a SIGKILL and also cause the offending pages to be claimed so they are no longer used in future tasks. SIGKILL is used to ensure that the process does not try to coredump and result in an attempt to read the memory again from within kernel space. Although there is a HV call to scrub the memory (mem_scrub), there is no easy way to guarantee that the real memory address(es) are not used by other tasks. Clearing the error with mem_scrub would zero the memory and cause the other processes to proceed with bad data. The handling of other non-resumable errors remain unchanged and will cause a panic. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'tools/build/feature/test-all.c')