diff options
Diffstat (limited to 'drivers/staging/ramzswap/ramzswap_drv.c')
-rw-r--r-- | drivers/staging/ramzswap/ramzswap_drv.c | 144 |
1 files changed, 86 insertions, 58 deletions
diff --git a/drivers/staging/ramzswap/ramzswap_drv.c b/drivers/staging/ramzswap/ramzswap_drv.c index 989fac5..5e422e2 100644 --- a/drivers/staging/ramzswap/ramzswap_drv.c +++ b/drivers/staging/ramzswap/ramzswap_drv.c @@ -1,7 +1,7 @@ /* * Compressed RAM based swap device * - * Copyright (C) 2008, 2009 Nitin Gupta + * Copyright (C) 2008, 2009, 2010 Nitin Gupta * * This code is released using a dual license strategy: BSD/GPL * You can choose the licence that better fits your requirements. @@ -24,12 +24,10 @@ #include <linux/genhd.h> #include <linux/highmem.h> #include <linux/lzo.h> -#include <linux/mutex.h> #include <linux/string.h> #include <linux/swap.h> #include <linux/swapops.h> #include <linux/vmalloc.h> -#include <linux/version.h> #include "ramzswap_drv.h" @@ -222,7 +220,7 @@ out: return ret; } -void ramzswap_ioctl_get_stats(struct ramzswap *rzs, +static void ramzswap_ioctl_get_stats(struct ramzswap *rzs, struct ramzswap_ioctl_stats *s) { strncpy(s->backing_swap_name, rzs->backing_swap_name, @@ -240,7 +238,8 @@ void ramzswap_ioctl_get_stats(struct ramzswap *rzs, mem_used = xv_get_total_size_bytes(rzs->mem_pool) + (rs->pages_expand << PAGE_SHIFT); - succ_writes = rs->num_writes - rs->failed_writes; + succ_writes = rzs_stat64_read(rzs, &rs->num_writes) - + rzs_stat64_read(rzs, &rs->failed_writes); if (succ_writes && rs->pages_stored) { good_compress_perc = rs->good_compress * 100 @@ -249,11 +248,12 @@ void ramzswap_ioctl_get_stats(struct ramzswap *rzs, / rs->pages_stored; } - s->num_reads = rs->num_reads; - s->num_writes = rs->num_writes; - s->failed_reads = rs->failed_reads; - s->failed_writes = rs->failed_writes; - s->invalid_io = rs->invalid_io; + s->num_reads = rzs_stat64_read(rzs, &rs->num_reads); + s->num_writes = rzs_stat64_read(rzs, &rs->num_writes); + s->failed_reads = rzs_stat64_read(rzs, &rs->failed_reads); + s->failed_writes = rzs_stat64_read(rzs, &rs->failed_writes); + s->invalid_io = rzs_stat64_read(rzs, &rs->invalid_io); + s->notify_free = rzs_stat64_read(rzs, &rs->notify_free); s->pages_zero = rs->pages_zero; s->good_compress_pct = good_compress_perc; @@ -265,8 +265,8 @@ void ramzswap_ioctl_get_stats(struct ramzswap *rzs, s->compr_data_size = rs->compr_size; s->mem_used_total = mem_used; - s->bdev_num_reads = rs->bdev_num_reads; - s->bdev_num_writes = rs->bdev_num_writes; + s->bdev_num_reads = rzs_stat64_read(rzs, &rs->bdev_num_reads); + s->bdev_num_writes = rzs_stat64_read(rzs, &rs->bdev_num_writes); } #endif /* CONFIG_RAMZSWAP_STATS */ } @@ -502,6 +502,14 @@ static int setup_backing_swap(struct ramzswap *rzs) goto bad_param; } disksize = i_size_read(inode); + /* + * Can happen if user gives an extended partition as + * backing swap or simply a bad disk. + */ + if (!disksize) { + pr_err("Error reading backing swap size.\n"); + goto bad_param; + } } else if (S_ISREG(inode->i_mode)) { bdev = inode->i_sb->s_bdev; if (IS_SWAPFILE(inode)) { @@ -519,7 +527,6 @@ static int setup_backing_swap(struct ramzswap *rzs) rzs->swap_file = swap_file; rzs->backing_swap = bdev; rzs->disksize = disksize; - BUG_ON(!rzs->disksize); return 0; @@ -537,7 +544,7 @@ out: * Map logical page number 'pagenum' to physical page number * on backing swap device. For block device, this is a nop. */ -u32 map_backing_swap_page(struct ramzswap *rzs, u32 pagenum) +static u32 map_backing_swap_page(struct ramzswap *rzs, u32 pagenum) { u32 skip_pages, entries_per_page; size_t delta, se_offset, skipped; @@ -593,9 +600,13 @@ static void ramzswap_free_page(struct ramzswap *rzs, size_t index) u32 offset = rzs->table[index].offset; if (unlikely(!page)) { + /* + * No memory is allocated for zero filled pages. + * Simply clear zero page flag. + */ if (rzs_test_flag(rzs, index, RZS_ZERO)) { rzs_clear_flag(rzs, index, RZS_ZERO); - stat_dec(rzs->stats.pages_zero); + rzs_stat_dec(&rzs->stats.pages_zero); } return; } @@ -604,7 +615,7 @@ static void ramzswap_free_page(struct ramzswap *rzs, size_t index) clen = PAGE_SIZE; __free_page(page); rzs_clear_flag(rzs, index, RZS_UNCOMPRESSED); - stat_dec(rzs->stats.pages_expand); + rzs_stat_dec(&rzs->stats.pages_expand); goto out; } @@ -614,11 +625,11 @@ static void ramzswap_free_page(struct ramzswap *rzs, size_t index) xv_free(rzs->mem_pool, page, offset); if (clen <= PAGE_SIZE / 2) - stat_dec(rzs->stats.good_compress); + rzs_stat_dec(&rzs->stats.good_compress); out: rzs->stats.compr_size -= clen; - stat_dec(rzs->stats.pages_stored); + rzs_stat_dec(&rzs->stats.pages_stored); rzs->table[index].page = NULL; rzs->table[index].offset = 0; @@ -664,7 +675,6 @@ static int handle_uncompressed_page(struct ramzswap *rzs, struct bio *bio) return 0; } - /* * Called when request page is not present in ramzswap. * Its either in backing swap device (if present) or @@ -680,8 +690,8 @@ static int handle_ramzswap_fault(struct ramzswap *rzs, struct bio *bio) */ if (rzs->backing_swap) { u32 pagenum; - stat_dec(rzs->stats.num_reads); - stat_inc(rzs->stats.bdev_num_reads); + rzs_stat64_dec(rzs, &rzs->stats.num_reads); + rzs_stat64_inc(rzs, &rzs->stats.bdev_num_reads); bio->bi_bdev = rzs->backing_swap; /* @@ -719,7 +729,7 @@ static int ramzswap_read(struct ramzswap *rzs, struct bio *bio) struct zobj_header *zheader; unsigned char *user_mem, *cmem; - stat_inc(rzs->stats.num_reads); + rzs_stat64_inc(rzs, &rzs->stats.num_reads); page = bio->bi_io_vec[0].bv_page; index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT; @@ -731,7 +741,7 @@ static int ramzswap_read(struct ramzswap *rzs, struct bio *bio) if (!rzs->table[index].page) return handle_ramzswap_fault(rzs, bio); - /* Page is stored uncompressed since its incompressible */ + /* Page is stored uncompressed since it's incompressible */ if (unlikely(rzs_test_flag(rzs, index, RZS_UNCOMPRESSED))) return handle_uncompressed_page(rzs, bio); @@ -753,7 +763,7 @@ static int ramzswap_read(struct ramzswap *rzs, struct bio *bio) if (unlikely(ret != LZO_E_OK)) { pr_err("Decompression failed! err=%d, page=%u\n", ret, index); - stat_inc(rzs->stats.failed_reads); + rzs_stat64_inc(rzs, &rzs->stats.failed_reads); goto out; } @@ -777,7 +787,7 @@ static int ramzswap_write(struct ramzswap *rzs, struct bio *bio) struct page *page, *page_store; unsigned char *user_mem, *cmem, *src; - stat_inc(rzs->stats.num_writes); + rzs_stat64_inc(rzs, &rzs->stats.num_writes); page = bio->bi_io_vec[0].bv_page; index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT; @@ -789,25 +799,16 @@ static int ramzswap_write(struct ramzswap *rzs, struct bio *bio) * is no longer referenced by any process. So, its now safe * to free the memory that was allocated for this page. */ - if (rzs->table[index].page) + if (rzs->table[index].page || rzs_test_flag(rzs, index, RZS_ZERO)) ramzswap_free_page(rzs, index); - /* - * No memory ia allocated for zero filled pages. - * Simply clear zero page flag. - */ - if (rzs_test_flag(rzs, index, RZS_ZERO)) { - stat_dec(rzs->stats.pages_zero); - rzs_clear_flag(rzs, index, RZS_ZERO); - } - mutex_lock(&rzs->lock); user_mem = kmap_atomic(page, KM_USER0); if (page_zero_filled(user_mem)) { kunmap_atomic(user_mem, KM_USER0); mutex_unlock(&rzs->lock); - stat_inc(rzs->stats.pages_zero); + rzs_stat_inc(&rzs->stats.pages_zero); rzs_set_flag(rzs, index, RZS_ZERO); set_bit(BIO_UPTODATE, &bio->bi_flags); @@ -831,7 +832,7 @@ static int ramzswap_write(struct ramzswap *rzs, struct bio *bio) if (unlikely(ret != LZO_E_OK)) { mutex_unlock(&rzs->lock); pr_err("Compression failed! err=%d\n", ret); - stat_inc(rzs->stats.failed_writes); + rzs_stat64_inc(rzs, &rzs->stats.failed_writes); goto out; } @@ -854,13 +855,13 @@ static int ramzswap_write(struct ramzswap *rzs, struct bio *bio) mutex_unlock(&rzs->lock); pr_info("Error allocating memory for incompressible " "page: %u\n", index); - stat_inc(rzs->stats.failed_writes); + rzs_stat64_inc(rzs, &rzs->stats.failed_writes); goto out; } offset = 0; rzs_set_flag(rzs, index, RZS_UNCOMPRESSED); - stat_inc(rzs->stats.pages_expand); + rzs_stat_inc(&rzs->stats.pages_expand); rzs->table[index].page = page_store; src = kmap_atomic(page, KM_USER0); goto memstore; @@ -872,7 +873,7 @@ static int ramzswap_write(struct ramzswap *rzs, struct bio *bio) mutex_unlock(&rzs->lock); pr_info("Error allocating memory for compressed " "page: %u, size=%zu\n", index, clen); - stat_inc(rzs->stats.failed_writes); + rzs_stat64_inc(rzs, &rzs->stats.failed_writes); if (rzs->backing_swap) fwd_write_request = 1; goto out; @@ -901,9 +902,9 @@ memstore: /* Update stats */ rzs->stats.compr_size += clen; - stat_inc(rzs->stats.pages_stored); + rzs_stat_inc(&rzs->stats.pages_stored); if (clen <= PAGE_SIZE / 2) - stat_inc(rzs->stats.good_compress); + rzs_stat_inc(&rzs->stats.good_compress); mutex_unlock(&rzs->lock); @@ -913,7 +914,7 @@ memstore: out: if (fwd_write_request) { - stat_inc(rzs->stats.bdev_num_writes); + rzs_stat64_inc(rzs, &rzs->stats.bdev_num_writes); bio->bi_bdev = rzs->backing_swap; #if 0 /* @@ -941,7 +942,6 @@ out: return 0; } - /* * Check if request is within bounds and page aligned. */ @@ -975,7 +975,7 @@ static int ramzswap_make_request(struct request_queue *queue, struct bio *bio) } if (!valid_swap_request(rzs, bio)) { - stat_inc(rzs->stats.invalid_io); + rzs_stat64_inc(rzs, &rzs->stats.invalid_io); bio_io_error(bio); return 0; } @@ -1000,6 +1000,9 @@ static void reset_device(struct ramzswap *rzs) unsigned entries_per_page; unsigned long num_table_pages, entry = 0; + /* Do not accept any new I/O request */ + rzs->init_done = 0; + if (rzs->backing_swap && !rzs->num_extents) is_backing_blkdev = 1; @@ -1066,6 +1069,7 @@ static void reset_device(struct ramzswap *rzs) bd_release(rzs->backing_swap); filp_close(rzs->swap_file, NULL); rzs->backing_swap = NULL; + memset(rzs->backing_swap_name, 0, MAX_SWAP_NAME_LEN); } /* Reset stats */ @@ -1073,9 +1077,6 @@ static void reset_device(struct ramzswap *rzs) rzs->disksize = 0; rzs->memlimit = 0; - - /* Back to uninitialized state */ - rzs->init_done = 0; } static int ramzswap_ioctl_init_device(struct ramzswap *rzs) @@ -1276,6 +1277,11 @@ static int ramzswap_ioctl(struct block_device *bdev, fmode_t mode, ret = -EBUSY; goto out; } + + /* Make sure all pending I/O is finished */ + if (bdev) + fsync_bdev(bdev); + ret = ramzswap_ioctl_reset_device(rzs); break; @@ -1293,16 +1299,20 @@ static struct block_device_operations ramzswap_devops = { .owner = THIS_MODULE, }; -static void create_device(struct ramzswap *rzs, int device_id) +static int create_device(struct ramzswap *rzs, int device_id) { + int ret = 0; + mutex_init(&rzs->lock); + spin_lock_init(&rzs->stat64_lock); INIT_LIST_HEAD(&rzs->backing_swap_extent_list); rzs->queue = blk_alloc_queue(GFP_KERNEL); if (!rzs->queue) { pr_err("Error allocating disk queue for device %d\n", device_id); - return; + ret = -ENOMEM; + goto out; } blk_queue_make_request(rzs->queue, ramzswap_make_request); @@ -1314,7 +1324,8 @@ static void create_device(struct ramzswap *rzs, int device_id) blk_cleanup_queue(rzs->queue); pr_warning("Error allocating disk structure for device %d\n", device_id); - return; + ret = -ENOMEM; + goto out; } rzs->disk->major = ramzswap_major; @@ -1329,9 +1340,16 @@ static void create_device(struct ramzswap *rzs, int device_id) * or set equal to backing swap device (if provided) */ set_capacity(rzs->disk, 0); + + blk_queue_physical_block_size(rzs->disk->queue, PAGE_SIZE); + blk_queue_logical_block_size(rzs->disk->queue, PAGE_SIZE); + add_disk(rzs->disk); rzs->init_done = 0; + +out: + return ret; } static void destroy_device(struct ramzswap *rzs) @@ -1347,18 +1365,20 @@ static void destroy_device(struct ramzswap *rzs) static int __init ramzswap_init(void) { - int i, ret; + int ret, dev_id; if (num_devices > max_num_devices) { pr_warning("Invalid value for num_devices: %u\n", num_devices); - return -EINVAL; + ret = -EINVAL; + goto out; } ramzswap_major = register_blkdev(0, "ramzswap"); if (ramzswap_major <= 0) { pr_warning("Unable to get major number\n"); - return -EBUSY; + ret = -EBUSY; + goto out; } if (!num_devices) { @@ -1371,15 +1391,23 @@ static int __init ramzswap_init(void) devices = kzalloc(num_devices * sizeof(struct ramzswap), GFP_KERNEL); if (!devices) { ret = -ENOMEM; - goto out; + goto unregister; } - for (i = 0; i < num_devices; i++) - create_device(&devices[i], i); + for (dev_id = 0; dev_id < num_devices; dev_id++) { + ret = create_device(&devices[dev_id], dev_id); + if (ret) + goto free_devices; + } return 0; -out: + +free_devices: + while (dev_id) + destroy_device(&devices[--dev_id]); +unregister: unregister_blkdev(ramzswap_major, "ramzswap"); +out: return ret; } |