Staging: zram: Rename ramzswap to zram in code
authorNitin Gupta <ngupta@vflare.org>
Tue, 1 Jun 2010 08:01:25 +0000 (13:31 +0530)
committerGreg Kroah-Hartman <gregkh@suse.de>
Fri, 18 Jun 2010 19:49:48 +0000 (12:49 -0700)
Automated renames in code:
 - rzs* -> zram*
 - RZS* -> ZRAM*
 - ramzswap* -> zram*

Manual changes:
 - Edited comments/messages mentioning "swap"

Signed-off-by: Nitin Gupta <ngupta@vflare.org>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/staging/zram/zram_drv.c
drivers/staging/zram/zram_drv.h
drivers/staging/zram/zram_ioctl.h

index e9b064c21484453c0e40f1835d7fa1f2ed3433ce..3f778434dc9bbe5239918eb91c4fe92f53c96655 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Compressed RAM based swap device
+ * Compressed RAM block device
  *
  * Copyright (C) 2008, 2009, 2010  Nitin Gupta
  *
@@ -12,7 +12,7 @@
  * Project home: http://compcache.googlecode.com
  */
 
-#define KMSG_COMPONENT "ramzswap"
+#define KMSG_COMPONENT "zram"
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/lzo.h>
 #include <linux/string.h>
-#include <linux/swap.h>
-#include <linux/swapops.h>
 #include <linux/vmalloc.h>
 
 #include "zram_drv.h"
 
 /* Globals */
-static int ramzswap_major;
-static struct ramzswap *devices;
+static int zram_major;
+static struct zram *devices;
 
 /* Module params (documentation at end) */
 static unsigned int num_devices;
 
-static int rzs_test_flag(struct ramzswap *rzs, u32 index,
-                       enum rzs_pageflags flag)
+static int zram_test_flag(struct zram *zram, u32 index,
+                       enum zram_pageflags flag)
 {
-       return rzs->table[index].flags & BIT(flag);
+       return zram->table[index].flags & BIT(flag);
 }
 
-static void rzs_set_flag(struct ramzswap *rzs, u32 index,
-                       enum rzs_pageflags flag)
+static void zram_set_flag(struct zram *zram, u32 index,
+                       enum zram_pageflags flag)
 {
-       rzs->table[index].flags |= BIT(flag);
+       zram->table[index].flags |= BIT(flag);
 }
 
-static void rzs_clear_flag(struct ramzswap *rzs, u32 index,
-                       enum rzs_pageflags flag)
+static void zram_clear_flag(struct zram *zram, u32 index,
+                       enum zram_pageflags flag)
 {
-       rzs->table[index].flags &= ~BIT(flag);
+       zram->table[index].flags &= ~BIT(flag);
 }
 
 static int page_zero_filled(void *ptr)
@@ -72,50 +70,50 @@ static int page_zero_filled(void *ptr)
        return 1;
 }
 
-static void ramzswap_set_disksize(struct ramzswap *rzs, size_t totalram_bytes)
+static void zram_set_disksize(struct zram *zram, size_t totalram_bytes)
 {
-       if (!rzs->disksize) {
+       if (!zram->disksize) {
                pr_info(
                "disk size not provided. You can use disksize_kb module "
                "param to specify size.\nUsing default: (%u%% of RAM).\n",
                default_disksize_perc_ram
                );
-               rzs->disksize = default_disksize_perc_ram *
+               zram->disksize = default_disksize_perc_ram *
                                        (totalram_bytes / 100);
        }
 
-       if (rzs->disksize > 2 * (totalram_bytes)) {
+       if (zram->disksize > 2 * (totalram_bytes)) {
                pr_info(
-               "There is little point creating a ramzswap of greater than "
+               "There is little point creating a zram of greater than "
                "twice the size of memory since we expect a 2:1 compression "
-               "ratio. Note that ramzswap uses about 0.1%% of the size of "
-               "the swap device when not in use so a huge ramzswap is "
+               "ratio. Note that zram uses about 0.1%% of the size of "
+               "the disk when not in use so a huge zram is "
                "wasteful.\n"
                "\tMemory Size: %zu kB\n"
                "\tSize you selected: %zu kB\n"
                "Continuing anyway ...\n",
-               totalram_bytes >> 10, rzs->disksize
+               totalram_bytes >> 10, zram->disksize
                );
        }
 
-       rzs->disksize &= PAGE_MASK;
+       zram->disksize &= PAGE_MASK;
 }
 
-static void ramzswap_ioctl_get_stats(struct ramzswap *rzs,
-                       struct ramzswap_ioctl_stats *s)
+static void zram_ioctl_get_stats(struct zram *zram,
+                       struct zram_ioctl_stats *s)
 {
-       s->disksize = rzs->disksize;
+       s->disksize = zram->disksize;
 
-#if defined(CONFIG_RAMZSWAP_STATS)
+#if defined(CONFIG_ZRAM_STATS)
        {
-       struct ramzswap_stats *rs = &rzs->stats;
+       struct zram_stats *rs = &zram->stats;
        size_t succ_writes, mem_used;
        unsigned int good_compress_perc = 0, no_compress_perc = 0;
 
-       mem_used = xv_get_total_size_bytes(rzs->mem_pool)
+       mem_used = xv_get_total_size_bytes(zram->mem_pool)
                        + (rs->pages_expand << PAGE_SHIFT);
-       succ_writes = rzs_stat64_read(rzs, &rs->num_writes) -
-                       rzs_stat64_read(rzs, &rs->failed_writes);
+       succ_writes = zram_stat64_read(zram, &rs->num_writes) -
+                       zram_stat64_read(zram, &rs->failed_writes);
 
        if (succ_writes && rs->pages_stored) {
                good_compress_perc = rs->good_compress * 100
@@ -124,12 +122,12 @@ static void ramzswap_ioctl_get_stats(struct ramzswap *rzs,
                                        / rs->pages_stored;
        }
 
-       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->num_reads = zram_stat64_read(zram, &rs->num_reads);
+       s->num_writes = zram_stat64_read(zram, &rs->num_writes);
+       s->failed_reads = zram_stat64_read(zram, &rs->failed_reads);
+       s->failed_writes = zram_stat64_read(zram, &rs->failed_writes);
+       s->invalid_io = zram_stat64_read(zram, &rs->invalid_io);
+       s->notify_free = zram_stat64_read(zram, &rs->notify_free);
        s->pages_zero = rs->pages_zero;
 
        s->good_compress_pct = good_compress_perc;
@@ -141,34 +139,34 @@ static void ramzswap_ioctl_get_stats(struct ramzswap *rzs,
        s->compr_data_size = rs->compr_size;
        s->mem_used_total = mem_used;
        }
-#endif /* CONFIG_RAMZSWAP_STATS */
+#endif /* CONFIG_ZRAM_STATS */
 }
 
-static void ramzswap_free_page(struct ramzswap *rzs, size_t index)
+static void zram_free_page(struct zram *zram, size_t index)
 {
        u32 clen;
        void *obj;
 
-       struct page *page = rzs->table[index].page;
-       u32 offset = rzs->table[index].offset;
+       struct page *page = zram->table[index].page;
+       u32 offset = zram->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);
-                       rzs_stat_dec(&rzs->stats.pages_zero);
+               if (zram_test_flag(zram, index, ZRAM_ZERO)) {
+                       zram_clear_flag(zram, index, ZRAM_ZERO);
+                       zram_stat_dec(&zram->stats.pages_zero);
                }
                return;
        }
 
-       if (unlikely(rzs_test_flag(rzs, index, RZS_UNCOMPRESSED))) {
+       if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) {
                clen = PAGE_SIZE;
                __free_page(page);
-               rzs_clear_flag(rzs, index, RZS_UNCOMPRESSED);
-               rzs_stat_dec(&rzs->stats.pages_expand);
+               zram_clear_flag(zram, index, ZRAM_UNCOMPRESSED);
+               zram_stat_dec(&zram->stats.pages_expand);
                goto out;
        }
 
@@ -176,16 +174,16 @@ static void ramzswap_free_page(struct ramzswap *rzs, size_t index)
        clen = xv_get_object_size(obj) - sizeof(struct zobj_header);
        kunmap_atomic(obj, KM_USER0);
 
-       xv_free(rzs->mem_pool, page, offset);
+       xv_free(zram->mem_pool, page, offset);
        if (clen <= PAGE_SIZE / 2)
-               rzs_stat_dec(&rzs->stats.good_compress);
+               zram_stat_dec(&zram->stats.good_compress);
 
 out:
-       rzs->stats.compr_size -= clen;
-       rzs_stat_dec(&rzs->stats.pages_stored);
+       zram->stats.compr_size -= clen;
+       zram_stat_dec(&zram->stats.pages_stored);
 
-       rzs->table[index].page = NULL;
-       rzs->table[index].offset = 0;
+       zram->table[index].page = NULL;
+       zram->table[index].offset = 0;
 }
 
 static void handle_zero_page(struct page *page)
@@ -199,14 +197,14 @@ static void handle_zero_page(struct page *page)
        flush_dcache_page(page);
 }
 
-static void handle_uncompressed_page(struct ramzswap *rzs,
+static void handle_uncompressed_page(struct zram *zram,
                                struct page *page, u32 index)
 {
        unsigned char *user_mem, *cmem;
 
        user_mem = kmap_atomic(page, KM_USER0);
-       cmem = kmap_atomic(rzs->table[index].page, KM_USER1) +
-                       rzs->table[index].offset;
+       cmem = kmap_atomic(zram->table[index].page, KM_USER1) +
+                       zram->table[index].offset;
 
        memcpy(user_mem, cmem, PAGE_SIZE);
        kunmap_atomic(user_mem, KM_USER0);
@@ -215,14 +213,14 @@ static void handle_uncompressed_page(struct ramzswap *rzs,
        flush_dcache_page(page);
 }
 
-static int ramzswap_read(struct ramzswap *rzs, struct bio *bio)
+static int zram_read(struct zram *zram, struct bio *bio)
 {
 
        int i;
        u32 index;
        struct bio_vec *bvec;
 
-       rzs_stat64_inc(rzs, &rzs->stats.num_reads);
+       zram_stat64_inc(zram, &zram->stats.num_reads);
 
        index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT;
        bio_for_each_segment(bvec, bio, i) {
@@ -234,13 +232,13 @@ static int ramzswap_read(struct ramzswap *rzs, struct bio *bio)
 
                page = bvec->bv_page;
 
-               if (rzs_test_flag(rzs, index, RZS_ZERO)) {
+               if (zram_test_flag(zram, index, ZRAM_ZERO)) {
                        handle_zero_page(page);
                        continue;
                }
 
                /* Requested page is not present in compressed area */
-               if (unlikely(!rzs->table[index].page)) {
+               if (unlikely(!zram->table[index].page)) {
                        pr_debug("Read before write: sector=%lu, size=%u",
                                (ulong)(bio->bi_sector), bio->bi_size);
                        /* Do nothing */
@@ -248,16 +246,16 @@ static int ramzswap_read(struct ramzswap *rzs, struct bio *bio)
                }
 
                /* Page is stored uncompressed since it's incompressible */
-               if (unlikely(rzs_test_flag(rzs, index, RZS_UNCOMPRESSED))) {
-                       handle_uncompressed_page(rzs, page, index);
+               if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED))) {
+                       handle_uncompressed_page(zram, page, index);
                        continue;
                }
 
                user_mem = kmap_atomic(page, KM_USER0);
                clen = PAGE_SIZE;
 
-               cmem = kmap_atomic(rzs->table[index].page, KM_USER1) +
-                               rzs->table[index].offset;
+               cmem = kmap_atomic(zram->table[index].page, KM_USER1) +
+                               zram->table[index].offset;
 
                ret = lzo1x_decompress_safe(
                        cmem + sizeof(*zheader),
@@ -271,7 +269,7 @@ 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);
-                       rzs_stat64_inc(rzs, &rzs->stats.failed_reads);
+                       zram_stat64_inc(zram, &zram->stats.failed_reads);
                        goto out;
                }
 
@@ -288,13 +286,13 @@ out:
        return 0;
 }
 
-static int ramzswap_write(struct ramzswap *rzs, struct bio *bio)
+static int zram_write(struct zram *zram, struct bio *bio)
 {
        int i;
        u32 index;
        struct bio_vec *bvec;
 
-       rzs_stat64_inc(rzs, &rzs->stats.num_writes);
+       zram_stat64_inc(zram, &zram->stats.num_writes);
 
        index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT;
 
@@ -307,82 +305,83 @@ static int ramzswap_write(struct ramzswap *rzs, struct bio *bio)
                unsigned char *user_mem, *cmem, *src;
 
                page = bvec->bv_page;
-               src = rzs->compress_buffer;
+               src = zram->compress_buffer;
 
                /*
                 * System overwrites unused sectors. Free memory associated
                 * with this sector now.
                 */
-               if (rzs->table[index].page ||
-                               rzs_test_flag(rzs, index, RZS_ZERO))
-                       ramzswap_free_page(rzs, index);
+               if (zram->table[index].page ||
+                               zram_test_flag(zram, index, ZRAM_ZERO))
+                       zram_free_page(zram, index);
 
-               mutex_lock(&rzs->lock);
+               mutex_lock(&zram->lock);
 
                user_mem = kmap_atomic(page, KM_USER0);
                if (page_zero_filled(user_mem)) {
                        kunmap_atomic(user_mem, KM_USER0);
-                       mutex_unlock(&rzs->lock);
-                       rzs_stat_inc(&rzs->stats.pages_zero);
-                       rzs_set_flag(rzs, index, RZS_ZERO);
+                       mutex_unlock(&zram->lock);
+                       zram_stat_inc(&zram->stats.pages_zero);
+                       zram_set_flag(zram, index, ZRAM_ZERO);
                        continue;
                }
 
                ret = lzo1x_1_compress(user_mem, PAGE_SIZE, src, &clen,
-                                       rzs->compress_workmem);
+                                       zram->compress_workmem);
 
                kunmap_atomic(user_mem, KM_USER0);
 
                if (unlikely(ret != LZO_E_OK)) {
-                       mutex_unlock(&rzs->lock);
+                       mutex_unlock(&zram->lock);
                        pr_err("Compression failed! err=%d\n", ret);
-                       rzs_stat64_inc(rzs, &rzs->stats.failed_writes);
+                       zram_stat64_inc(zram, &zram->stats.failed_writes);
                        goto out;
                }
 
                /*
                 * Page is incompressible. Store it as-is (uncompressed)
-                * since we do not want to return too many swap write
+                * since we do not want to return too many disk write
                 * errors which has side effect of hanging the system.
                 */
                if (unlikely(clen > max_zpage_size)) {
                        clen = PAGE_SIZE;
                        page_store = alloc_page(GFP_NOIO | __GFP_HIGHMEM);
                        if (unlikely(!page_store)) {
-                               mutex_unlock(&rzs->lock);
+                               mutex_unlock(&zram->lock);
                                pr_info("Error allocating memory for "
                                        "incompressible page: %u\n", index);
-                               rzs_stat64_inc(rzs, &rzs->stats.failed_writes);
+                               zram_stat64_inc(zram,
+                                       &zram->stats.failed_writes);
                                goto out;
                        }
 
                        offset = 0;
-                       rzs_set_flag(rzs, index, RZS_UNCOMPRESSED);
-                       rzs_stat_inc(&rzs->stats.pages_expand);
-                       rzs->table[index].page = page_store;
+                       zram_set_flag(zram, index, ZRAM_UNCOMPRESSED);
+                       zram_stat_inc(&zram->stats.pages_expand);
+                       zram->table[index].page = page_store;
                        src = kmap_atomic(page, KM_USER0);
                        goto memstore;
                }
 
-               if (xv_malloc(rzs->mem_pool, clen + sizeof(*zheader),
-                               &rzs->table[index].page, &offset,
+               if (xv_malloc(zram->mem_pool, clen + sizeof(*zheader),
+                               &zram->table[index].page, &offset,
                                GFP_NOIO | __GFP_HIGHMEM)) {
-                       mutex_unlock(&rzs->lock);
+                       mutex_unlock(&zram->lock);
                        pr_info("Error allocating memory for compressed "
                                "page: %u, size=%zu\n", index, clen);
-                       rzs_stat64_inc(rzs, &rzs->stats.failed_writes);
+                       zram_stat64_inc(zram, &zram->stats.failed_writes);
                        goto out;
                }
 
 memstore:
-               rzs->table[index].offset = offset;
+               zram->table[index].offset = offset;
 
-               cmem = kmap_atomic(rzs->table[index].page, KM_USER1) +
-                               rzs->table[index].offset;
+               cmem = kmap_atomic(zram->table[index].page, KM_USER1) +
+                               zram->table[index].offset;
 
 #if 0
                /* Back-reference needed for memory defragmentation */
-               if (!rzs_test_flag(rzs, index, RZS_UNCOMPRESSED)) {
+               if (!zram_test_flag(zram, index, ZRAM_UNCOMPRESSED)) {
                        zheader = (struct zobj_header *)cmem;
                        zheader->table_idx = index;
                        cmem += sizeof(*zheader);
@@ -392,16 +391,16 @@ memstore:
                memcpy(cmem, src, clen);
 
                kunmap_atomic(cmem, KM_USER1);
-               if (unlikely(rzs_test_flag(rzs, index, RZS_UNCOMPRESSED)))
+               if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED)))
                        kunmap_atomic(src, KM_USER0);
 
                /* Update stats */
-               rzs->stats.compr_size += clen;
-               rzs_stat_inc(&rzs->stats.pages_stored);
+               zram->stats.compr_size += clen;
+               zram_stat_inc(&zram->stats.pages_stored);
                if (clen <= PAGE_SIZE / 2)
-                       rzs_stat_inc(&rzs->stats.good_compress);
+                       zram_stat_inc(&zram->stats.good_compress);
 
-               mutex_unlock(&rzs->lock);
+               mutex_unlock(&zram->lock);
                index++;
        }
 
@@ -417,10 +416,10 @@ out:
 /*
  * Check if request is within bounds and page aligned.
  */
-static inline int valid_io_request(struct ramzswap *rzs, struct bio *bio)
+static inline int valid_io_request(struct zram *zram, struct bio *bio)
 {
        if (unlikely(
-               (bio->bi_sector >= (rzs->disksize >> SECTOR_SHIFT)) ||
+               (bio->bi_sector >= (zram->disksize >> SECTOR_SHIFT)) ||
                (bio->bi_sector & (SECTORS_PER_PAGE - 1)) ||
                (bio->bi_size & (PAGE_SIZE - 1)))) {
 
@@ -432,160 +431,160 @@ static inline int valid_io_request(struct ramzswap *rzs, struct bio *bio)
 }
 
 /*
- * Handler function for all ramzswap I/O requests.
+ * Handler function for all zram I/O requests.
  */
-static int ramzswap_make_request(struct request_queue *queue, struct bio *bio)
+static int zram_make_request(struct request_queue *queue, struct bio *bio)
 {
        int ret = 0;
-       struct ramzswap *rzs = queue->queuedata;
+       struct zram *zram = queue->queuedata;
 
-       if (unlikely(!rzs->init_done)) {
+       if (unlikely(!zram->init_done)) {
                bio_io_error(bio);
                return 0;
        }
 
-       if (!valid_io_request(rzs, bio)) {
-               rzs_stat64_inc(rzs, &rzs->stats.invalid_io);
+       if (!valid_io_request(zram, bio)) {
+               zram_stat64_inc(zram, &zram->stats.invalid_io);
                bio_io_error(bio);
                return 0;
        }
 
        switch (bio_data_dir(bio)) {
        case READ:
-               ret = ramzswap_read(rzs, bio);
+               ret = zram_read(zram, bio);
                break;
 
        case WRITE:
-               ret = ramzswap_write(rzs, bio);
+               ret = zram_write(zram, bio);
                break;
        }
 
        return ret;
 }
 
-static void reset_device(struct ramzswap *rzs)
+static void reset_device(struct zram *zram)
 {
        size_t index;
 
        /* Do not accept any new I/O request */
-       rzs->init_done = 0;
+       zram->init_done = 0;
 
        /* Free various per-device buffers */
-       kfree(rzs->compress_workmem);
-       free_pages((unsigned long)rzs->compress_buffer, 1);
+       kfree(zram->compress_workmem);
+       free_pages((unsigned long)zram->compress_buffer, 1);
 
-       rzs->compress_workmem = NULL;
-       rzs->compress_buffer = NULL;
+       zram->compress_workmem = NULL;
+       zram->compress_buffer = NULL;
 
-       /* Free all pages that are still in this ramzswap device */
-       for (index = 0; index < rzs->disksize >> PAGE_SHIFT; index++) {
+       /* Free all pages that are still in this zram device */
+       for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) {
                struct page *page;
                u16 offset;
 
-               page = rzs->table[index].page;
-               offset = rzs->table[index].offset;
+               page = zram->table[index].page;
+               offset = zram->table[index].offset;
 
                if (!page)
                        continue;
 
-               if (unlikely(rzs_test_flag(rzs, index, RZS_UNCOMPRESSED)))
+               if (unlikely(zram_test_flag(zram, index, ZRAM_UNCOMPRESSED)))
                        __free_page(page);
                else
-                       xv_free(rzs->mem_pool, page, offset);
+                       xv_free(zram->mem_pool, page, offset);
        }
 
-       vfree(rzs->table);
-       rzs->table = NULL;
+       vfree(zram->table);
+       zram->table = NULL;
 
-       xv_destroy_pool(rzs->mem_pool);
-       rzs->mem_pool = NULL;
+       xv_destroy_pool(zram->mem_pool);
+       zram->mem_pool = NULL;
 
        /* Reset stats */
-       memset(&rzs->stats, 0, sizeof(rzs->stats));
+       memset(&zram->stats, 0, sizeof(zram->stats));
 
-       rzs->disksize = 0;
+       zram->disksize = 0;
 }
 
-static int ramzswap_ioctl_init_device(struct ramzswap *rzs)
+static int zram_ioctl_init_device(struct zram *zram)
 {
        int ret;
        size_t num_pages;
 
-       if (rzs->init_done) {
+       if (zram->init_done) {
                pr_info("Device already initialized!\n");
                return -EBUSY;
        }
 
-       ramzswap_set_disksize(rzs, totalram_pages << PAGE_SHIFT);
+       zram_set_disksize(zram, totalram_pages << PAGE_SHIFT);
 
-       rzs->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
-       if (!rzs->compress_workmem) {
+       zram->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
+       if (!zram->compress_workmem) {
                pr_err("Error allocating compressor working memory!\n");
                ret = -ENOMEM;
                goto fail;
        }
 
-       rzs->compress_buffer = (void *)__get_free_pages(__GFP_ZERO, 1);
-       if (!rzs->compress_buffer) {
+       zram->compress_buffer = (void *)__get_free_pages(__GFP_ZERO, 1);
+       if (!zram->compress_buffer) {
                pr_err("Error allocating compressor buffer space\n");
                ret = -ENOMEM;
                goto fail;
        }
 
-       num_pages = rzs->disksize >> PAGE_SHIFT;
-       rzs->table = vmalloc(num_pages * sizeof(*rzs->table));
-       if (!rzs->table) {
-               pr_err("Error allocating ramzswap address table\n");
+       num_pages = zram->disksize >> PAGE_SHIFT;
+       zram->table = vmalloc(num_pages * sizeof(*zram->table));
+       if (!zram->table) {
+               pr_err("Error allocating zram address table\n");
                /* To prevent accessing table entries during cleanup */
-               rzs->disksize = 0;
+               zram->disksize = 0;
                ret = -ENOMEM;
                goto fail;
        }
-       memset(rzs->table, 0, num_pages * sizeof(*rzs->table));
+       memset(zram->table, 0, num_pages * sizeof(*zram->table));
 
-       set_capacity(rzs->disk, rzs->disksize >> SECTOR_SHIFT);
+       set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
 
-       /* ramzswap devices sort of resembles non-rotational disks */
-       queue_flag_set_unlocked(QUEUE_FLAG_NONROT, rzs->disk->queue);
+       /* zram devices sort of resembles non-rotational disks */
+       queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue);
 
-       rzs->mem_pool = xv_create_pool();
-       if (!rzs->mem_pool) {
+       zram->mem_pool = xv_create_pool();
+       if (!zram->mem_pool) {
                pr_err("Error creating memory pool\n");
                ret = -ENOMEM;
                goto fail;
        }
 
-       rzs->init_done = 1;
+       zram->init_done = 1;
 
        pr_debug("Initialization done!\n");
        return 0;
 
 fail:
-       reset_device(rzs);
+       reset_device(zram);
 
        pr_err("Initialization failed: err=%d\n", ret);
        return ret;
 }
 
-static int ramzswap_ioctl_reset_device(struct ramzswap *rzs)
+static int zram_ioctl_reset_device(struct zram *zram)
 {
-       if (rzs->init_done)
-               reset_device(rzs);
+       if (zram->init_done)
+               reset_device(zram);
 
        return 0;
 }
 
-static int ramzswap_ioctl(struct block_device *bdev, fmode_t mode,
+static int zram_ioctl(struct block_device *bdev, fmode_t mode,
                        unsigned int cmd, unsigned long arg)
 {
        int ret = 0;
        size_t disksize_kb;
 
-       struct ramzswap *rzs = bdev->bd_disk->private_data;
+       struct zram *zram = bdev->bd_disk->private_data;
 
        switch (cmd) {
-       case RZSIO_SET_DISKSIZE_KB:
-               if (rzs->init_done) {
+       case ZRAMIO_SET_DISKSIZE_KB:
+               if (zram->init_done) {
                        ret = -EBUSY;
                        goto out;
                }
@@ -594,14 +593,14 @@ static int ramzswap_ioctl(struct block_device *bdev, fmode_t mode,
                        ret = -EFAULT;
                        goto out;
                }
-               rzs->disksize = disksize_kb << 10;
+               zram->disksize = disksize_kb << 10;
                pr_info("Disk size set to %zu kB\n", disksize_kb);
                break;
 
-       case RZSIO_GET_STATS:
+       case ZRAMIO_GET_STATS:
        {
-               struct ramzswap_ioctl_stats *stats;
-               if (!rzs->init_done) {
+               struct zram_ioctl_stats *stats;
+               if (!zram->init_done) {
                        ret = -ENOTTY;
                        goto out;
                }
@@ -610,7 +609,7 @@ static int ramzswap_ioctl(struct block_device *bdev, fmode_t mode,
                        ret = -ENOMEM;
                        goto out;
                }
-               ramzswap_ioctl_get_stats(rzs, stats);
+               zram_ioctl_get_stats(zram, stats);
                if (copy_to_user((void *)arg, stats, sizeof(*stats))) {
                        kfree(stats);
                        ret = -EFAULT;
@@ -619,11 +618,11 @@ static int ramzswap_ioctl(struct block_device *bdev, fmode_t mode,
                kfree(stats);
                break;
        }
-       case RZSIO_INIT:
-               ret = ramzswap_ioctl_init_device(rzs);
+       case ZRAMIO_INIT:
+               ret = zram_ioctl_init_device(zram);
                break;
 
-       case RZSIO_RESET:
+       case ZRAMIO_RESET:
                /* Do not reset an active device! */
                if (bdev->bd_holders) {
                        ret = -EBUSY;
@@ -634,7 +633,7 @@ static int ramzswap_ioctl(struct block_device *bdev, fmode_t mode,
                if (bdev)
                        fsync_bdev(bdev);
 
-               ret = ramzswap_ioctl_reset_device(rzs);
+               ret = zram_ioctl_reset_device(zram);
                break;
 
        default:
@@ -646,88 +645,88 @@ out:
        return ret;
 }
 
-void ramzswap_slot_free_notify(struct block_device *bdev, unsigned long index)
+void zram_slot_free_notify(struct block_device *bdev, unsigned long index)
 {
-       struct ramzswap *rzs;
+       struct zram *zram;
 
-       rzs = bdev->bd_disk->private_data;
-       ramzswap_free_page(rzs, index);
-       rzs_stat64_inc(rzs, &rzs->stats.notify_free);
+       zram = bdev->bd_disk->private_data;
+       zram_free_page(zram, index);
+       zram_stat64_inc(zram, &zram->stats.notify_free);
 }
 
-static const struct block_device_operations ramzswap_devops = {
-       .ioctl = ramzswap_ioctl,
-       .swap_slot_free_notify = ramzswap_slot_free_notify,
+static const struct block_device_operations zram_devops = {
+       .ioctl = zram_ioctl,
+       .swap_slot_free_notify = zram_slot_free_notify,
        .owner = THIS_MODULE
 };
 
-static int create_device(struct ramzswap *rzs, int device_id)
+static int create_device(struct zram *zram, int device_id)
 {
        int ret = 0;
 
-       mutex_init(&rzs->lock);
-       spin_lock_init(&rzs->stat64_lock);
+       mutex_init(&zram->lock);
+       spin_lock_init(&zram->stat64_lock);
 
-       rzs->queue = blk_alloc_queue(GFP_KERNEL);
-       if (!rzs->queue) {
+       zram->queue = blk_alloc_queue(GFP_KERNEL);
+       if (!zram->queue) {
                pr_err("Error allocating disk queue for device %d\n",
                        device_id);
                ret = -ENOMEM;
                goto out;
        }
 
-       blk_queue_make_request(rzs->queue, ramzswap_make_request);
-       rzs->queue->queuedata = rzs;
+       blk_queue_make_request(zram->queue, zram_make_request);
+       zram->queue->queuedata = zram;
 
         /* gendisk structure */
-       rzs->disk = alloc_disk(1);
-       if (!rzs->disk) {
-               blk_cleanup_queue(rzs->queue);
+       zram->disk = alloc_disk(1);
+       if (!zram->disk) {
+               blk_cleanup_queue(zram->queue);
                pr_warning("Error allocating disk structure for device %d\n",
                        device_id);
                ret = -ENOMEM;
                goto out;
        }
 
-       rzs->disk->major = ramzswap_major;
-       rzs->disk->first_minor = device_id;
-       rzs->disk->fops = &ramzswap_devops;
-       rzs->disk->queue = rzs->queue;
-       rzs->disk->private_data = rzs;
-       snprintf(rzs->disk->disk_name, 16, "ramzswap%d", device_id);
+       zram->disk->major = zram_major;
+       zram->disk->first_minor = device_id;
+       zram->disk->fops = &zram_devops;
+       zram->disk->queue = zram->queue;
+       zram->disk->private_data = zram;
+       snprintf(zram->disk->disk_name, 16, "zram%d", device_id);
 
-       /* Actual capacity set using RZSIO_SET_DISKSIZE_KB ioctl */
-       set_capacity(rzs->disk, 0);
+       /* Actual capacity set using ZRAMIO_SET_DISKSIZE_KB ioctl */
+       set_capacity(zram->disk, 0);
 
        /*
         * To ensure that we always get PAGE_SIZE aligned
         * and n*PAGE_SIZED sized I/O requests.
         */
-       blk_queue_physical_block_size(rzs->disk->queue, PAGE_SIZE);
-       blk_queue_logical_block_size(rzs->disk->queue, PAGE_SIZE);
-       blk_queue_io_min(rzs->disk->queue, PAGE_SIZE);
-       blk_queue_io_opt(rzs->disk->queue, PAGE_SIZE);
+       blk_queue_physical_block_size(zram->disk->queue, PAGE_SIZE);
+       blk_queue_logical_block_size(zram->disk->queue, PAGE_SIZE);
+       blk_queue_io_min(zram->disk->queue, PAGE_SIZE);
+       blk_queue_io_opt(zram->disk->queue, PAGE_SIZE);
 
-       add_disk(rzs->disk);
+       add_disk(zram->disk);
 
-       rzs->init_done = 0;
+       zram->init_done = 0;
 
 out:
        return ret;
 }
 
-static void destroy_device(struct ramzswap *rzs)
+static void destroy_device(struct zram *zram)
 {
-       if (rzs->disk) {
-               del_gendisk(rzs->disk);
-               put_disk(rzs->disk);
+       if (zram->disk) {
+               del_gendisk(zram->disk);
+               put_disk(zram->disk);
        }
 
-       if (rzs->queue)
-               blk_cleanup_queue(rzs->queue);
+       if (zram->queue)
+               blk_cleanup_queue(zram->queue);
 }
 
-static int __init ramzswap_init(void)
+static int __init zram_init(void)
 {
        int ret, dev_id;
 
@@ -738,8 +737,8 @@ static int __init ramzswap_init(void)
                goto out;
        }
 
-       ramzswap_major = register_blkdev(0, "ramzswap");
-       if (ramzswap_major <= 0) {
+       zram_major = register_blkdev(0, "zram");
+       if (zram_major <= 0) {
                pr_warning("Unable to get major number\n");
                ret = -EBUSY;
                goto out;
@@ -752,7 +751,7 @@ static int __init ramzswap_init(void)
 
        /* Allocate the device array and initialize each one */
        pr_info("Creating %u devices ...\n", num_devices);
-       devices = kzalloc(num_devices * sizeof(struct ramzswap), GFP_KERNEL);
+       devices = kzalloc(num_devices * sizeof(struct zram), GFP_KERNEL);
        if (!devices) {
                ret = -ENOMEM;
                goto unregister;
@@ -770,36 +769,36 @@ free_devices:
        while (dev_id)
                destroy_device(&devices[--dev_id]);
 unregister:
-       unregister_blkdev(ramzswap_major, "ramzswap");
+       unregister_blkdev(zram_major, "zram");
 out:
        return ret;
 }
 
-static void __exit ramzswap_exit(void)
+static void __exit zram_exit(void)
 {
        int i;
-       struct ramzswap *rzs;
+       struct zram *zram;
 
        for (i = 0; i < num_devices; i++) {
-               rzs = &devices[i];
+               zram = &devices[i];
 
-               destroy_device(rzs);
-               if (rzs->init_done)
-                       reset_device(rzs);
+               destroy_device(zram);
+               if (zram->init_done)
+                       reset_device(zram);
        }
 
-       unregister_blkdev(ramzswap_major, "ramzswap");
+       unregister_blkdev(zram_major, "zram");
 
        kfree(devices);
        pr_debug("Cleanup done!\n");
 }
 
 module_param(num_devices, uint, 0);
-MODULE_PARM_DESC(num_devices, "Number of ramzswap devices");
+MODULE_PARM_DESC(num_devices, "Number of zram devices");
 
-module_init(ramzswap_init);
-module_exit(ramzswap_exit);
+module_init(zram_init);
+module_exit(zram_exit);
 
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_AUTHOR("Nitin Gupta <ngupta@vflare.org>");
-MODULE_DESCRIPTION("Compressed RAM Based Swap Device");
+MODULE_DESCRIPTION("Compressed RAM Block Device");
index 4d2e48a23474516fe85bed820161b18fdc2abef9..945f9740442f016d9d575736cbf547afc8e28404 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Compressed RAM based swap device
+ * Compressed RAM block device
  *
  * Copyright (C) 2008, 2009, 2010  Nitin Gupta
  *
@@ -12,8 +12,8 @@
  * Project home: http://compcache.googlecode.com
  */
 
-#ifndef _RAMZSWAP_DRV_H_
-#define _RAMZSWAP_DRV_H_
+#ifndef _ZRAM_DRV_H_
+#define _ZRAM_DRV_H_
 
 #include <linux/spinlock.h>
 #include <linux/mutex.h>
@@ -41,7 +41,7 @@ struct zobj_header {
 
 /*-- Configurable parameters */
 
-/* Default ramzswap disk size: 25% of total RAM */
+/* Default zram disk size: 25% of total RAM */
 static const unsigned default_disksize_perc_ram = 25;
 
 /*
@@ -63,23 +63,20 @@ static const unsigned max_zpage_size = PAGE_SIZE / 4 * 3;
 #define SECTORS_PER_PAGE_SHIFT (PAGE_SHIFT - SECTOR_SHIFT)
 #define SECTORS_PER_PAGE       (1 << SECTORS_PER_PAGE_SHIFT)
 
-/* Flags for ramzswap pages (table[page_no].flags) */
-enum rzs_pageflags {
+/* Flags for zram pages (table[page_no].flags) */
+enum zram_pageflags {
        /* Page is stored uncompressed */
-       RZS_UNCOMPRESSED,
+       ZRAM_UNCOMPRESSED,
 
        /* Page consists entirely of zeros */
-       RZS_ZERO,
+       ZRAM_ZERO,
 
-       __NR_RZS_PAGEFLAGS,
+       __NR_ZRAM_PAGEFLAGS,
 };
 
 /*-- Data structures */
 
-/*
- * Allocated for each swap slot, indexed by page no.
- * These table entries must fit exactly in a page.
- */
+/* Allocated for each disk page */
 struct table {
        struct page *page;
        u16 offset;
@@ -87,17 +84,17 @@ struct table {
        u8 flags;
 } __attribute__((aligned(4)));
 
-struct ramzswap_stats {
+struct zram_stats {
        /* basic stats */
        size_t compr_size;      /* compressed size of pages stored -
                                 * needed to enforce memlimit */
        /* more stats */
-#if defined(CONFIG_RAMZSWAP_STATS)
+#if defined(CONFIG_ZRAM_STATS)
        u64 num_reads;          /* failed + successful */
        u64 num_writes;         /* --do-- */
        u64 failed_reads;       /* should NEVER! happen */
        u64 failed_writes;      /* can happen when memory is too low */
-       u64 invalid_io;         /* non-swap I/O requests */
+       u64 invalid_io;         /* non-page-aligned I/O requests */
        u64 notify_free;        /* no. of swap slot free notifications */
        u32 pages_zero;         /* no. of zero filled pages */
        u32 pages_stored;       /* no. of pages currently stored */
@@ -106,7 +103,7 @@ struct ramzswap_stats {
 #endif
 };
 
-struct ramzswap {
+struct zram {
        struct xv_pool *mem_pool;
        void *compress_workmem;
        void *compress_buffer;
@@ -118,51 +115,50 @@ struct ramzswap {
        struct gendisk *disk;
        int init_done;
        /*
-        * This is limit on amount of *uncompressed* worth of data
-        * we can hold. When backing swap device is provided, it is
-        * set equal to device size.
+        * This is the limit on amount of *uncompressed* worth of data
+        * we can store in a disk.
         */
        size_t disksize;        /* bytes */
 
-       struct ramzswap_stats stats;
+       struct zram_stats stats;
 };
 
 /*-- */
 
 /* Debugging and Stats */
-#if defined(CONFIG_RAMZSWAP_STATS)
-static void rzs_stat_inc(u32 *v)
+#if defined(CONFIG_ZRAM_STATS)
+static void zram_stat_inc(u32 *v)
 {
        *v = *v + 1;
 }
 
-static void rzs_stat_dec(u32 *v)
+static void zram_stat_dec(u32 *v)
 {
        *v = *v - 1;
 }
 
-static void rzs_stat64_inc(struct ramzswap *rzs, u64 *v)
+static void zram_stat64_inc(struct zram *zram, u64 *v)
 {
-       spin_lock(&rzs->stat64_lock);
+       spin_lock(&zram->stat64_lock);
        *v = *v + 1;
-       spin_unlock(&rzs->stat64_lock);
+       spin_unlock(&zram->stat64_lock);
 }
 
-static u64 rzs_stat64_read(struct ramzswap *rzs, u64 *v)
+static u64 zram_stat64_read(struct zram *zram, u64 *v)
 {
        u64 val;
 
-       spin_lock(&rzs->stat64_lock);
+       spin_lock(&zram->stat64_lock);
        val = *v;
-       spin_unlock(&rzs->stat64_lock);
+       spin_unlock(&zram->stat64_lock);
 
        return val;
 }
 #else
-#define rzs_stat_inc(v)
-#define rzs_stat_dec(v)
-#define rzs_stat64_inc(r, v)
-#define rzs_stat64_read(r, v)
-#endif /* CONFIG_RAMZSWAP_STATS */
+#define zram_stat_inc(v)
+#define zram_stat_dec(v)
+#define zram_stat64_inc(r, v)
+#define zram_stat64_read(r, v)
+#endif /* CONFIG_ZRAM_STATS */
 
 #endif
index db94bcb429674846e696803bde6371981f0ad567..5c415fa4f17bb599a9e1c445dbd41787ef7e0974 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Compressed RAM based swap device
+ * Compressed RAM block device
  *
  * Copyright (C) 2008, 2009, 2010  Nitin Gupta
  *
  * Project home: http://compcache.googlecode.com
  */
 
-#ifndef _RAMZSWAP_IOCTL_H_
-#define _RAMZSWAP_IOCTL_H_
+#ifndef _ZRAM_IOCTL_H_
+#define _ZRAM_IOCTL_H_
 
-struct ramzswap_ioctl_stats {
-       u64 disksize;           /* user specified or equal to backing swap
-                                * size (if present) */
+struct zram_ioctl_stats {
+       u64 disksize;           /* disksize in bytes (user specifies in KB) */
        u64 num_reads;          /* failed + successful */
        u64 num_writes;         /* --do-- */
        u64 failed_reads;       /* should NEVER! happen */
        u64 failed_writes;      /* can happen when memory is too low */
-       u64 invalid_io;         /* non-swap I/O requests */
+       u64 invalid_io;         /* non-page-aligned I/O requests */
        u64 notify_free;        /* no. of swap slot free notifications */
        u32 pages_zero;         /* no. of zero filled pages */
        u32 good_compress_pct;  /* no. of pages with compression ratio<=50% */
@@ -34,9 +33,9 @@ struct ramzswap_ioctl_stats {
        u64 mem_used_total;
 } __attribute__ ((packed, aligned(4)));
 
-#define RZSIO_SET_DISKSIZE_KB  _IOW('z', 0, size_t)
-#define RZSIO_GET_STATS                _IOR('z', 1, struct ramzswap_ioctl_stats)
-#define RZSIO_INIT             _IO('z', 2)
-#define RZSIO_RESET            _IO('z', 3)
+#define ZRAMIO_SET_DISKSIZE_KB _IOW('z', 0, size_t)
+#define ZRAMIO_GET_STATS       _IOR('z', 1, struct zram_ioctl_stats)
+#define ZRAMIO_INIT            _IO('z', 2)
+#define ZRAMIO_RESET           _IO('z', 3)
 
 #endif