diff options
Diffstat (limited to 'drivers/mtd/nand/nandsim.c')
| -rw-r--r-- | drivers/mtd/nand/nandsim.c | 285 |
1 files changed, 261 insertions, 24 deletions
diff --git a/drivers/mtd/nand/nandsim.c b/drivers/mtd/nand/nandsim.c index fdf82cf2444..baa6f95e962 100644 --- a/drivers/mtd/nand/nandsim.c +++ b/drivers/mtd/nand/nandsim.c @@ -38,6 +38,8 @@ #include <linux/delay.h> #include <linux/list.h> #include <linux/random.h> +#include <linux/fs.h> +#include <linux/pagemap.h> /* Default simulator parameters values */ #if !defined(CONFIG_NANDSIM_FIRST_ID_BYTE) || \ @@ -100,6 +102,7 @@ static unsigned int bitflips = 0; static char *gravepages = NULL; static unsigned int rptwear = 0; static unsigned int overridesize = 0; +static char *cache_file = NULL; module_param(first_id_byte, uint, 0400); module_param(second_id_byte, uint, 0400); @@ -122,12 +125,13 @@ module_param(bitflips, uint, 0400); module_param(gravepages, charp, 0400); module_param(rptwear, uint, 0400); module_param(overridesize, uint, 0400); +module_param(cache_file, charp, 0400); MODULE_PARM_DESC(first_id_byte, "The first byte returned by NAND Flash 'read ID' command (manufacturer ID)"); MODULE_PARM_DESC(second_id_byte, "The second byte returned by NAND Flash 'read ID' command (chip ID)"); MODULE_PARM_DESC(third_id_byte, "The third byte returned by NAND Flash 'read ID' command"); MODULE_PARM_DESC(fourth_id_byte, "The fourth byte returned by NAND Flash 'read ID' command"); -MODULE_PARM_DESC(access_delay, "Initial page access delay (microiseconds)"); +MODULE_PARM_DESC(access_delay, "Initial page access delay (microseconds)"); MODULE_PARM_DESC(programm_delay, "Page programm delay (microseconds"); MODULE_PARM_DESC(erase_delay, "Sector erase delay (milliseconds)"); MODULE_PARM_DESC(output_cycle, "Word output (from flash) time (nanodeconds)"); @@ -153,6 +157,7 @@ MODULE_PARM_DESC(rptwear, "Number of erases inbetween reporting wear, if MODULE_PARM_DESC(overridesize, "Specifies the NAND Flash size overriding the ID bytes. " "The size is specified in erase blocks and as the exponent of a power of two" " e.g. 5 means a size of 32 erase blocks"); +MODULE_PARM_DESC(cache_file, "File to use to cache nand pages instead of memory"); /* The largest possible page size */ #define NS_LARGEST_PAGE_SIZE 2048 @@ -266,6 +271,9 @@ MODULE_PARM_DESC(overridesize, "Specifies the NAND Flash size overriding the I */ #define NS_MAX_PREVSTATES 1 +/* Maximum page cache pages needed to read or write a NAND page to the cache_file */ +#define NS_MAX_HELD_PAGES 16 + /* * A union to represent flash memory contents and flash buffer. */ @@ -335,6 +343,13 @@ struct nandsim { int ale; /* address Latch Enable */ int wp; /* write Protect */ } lines; + + /* Fields needed when using a cache file */ + struct file *cfile; /* Open file */ + unsigned char *pages_written; /* Which pages have been written */ + void *file_buf; + struct page *held_pages[NS_MAX_HELD_PAGES]; + int held_cnt; }; /* @@ -427,11 +442,43 @@ static u_char ns_verify_buf[NS_LARGEST_PAGE_SIZE]; */ static int alloc_device(struct nandsim *ns) { - int i; + struct file *cfile; + int i, err; + + if (cache_file) { + cfile = filp_open(cache_file, O_CREAT | O_RDWR | O_LARGEFILE, 0600); + if (IS_ERR(cfile)) + return PTR_ERR(cfile); + if (!cfile->f_op || (!cfile->f_op->read && !cfile->f_op->aio_read)) { + NS_ERR("alloc_device: cache file not readable\n"); + err = -EINVAL; + goto err_close; + } + if (!cfile->f_op->write && !cfile->f_op->aio_write) { + NS_ERR("alloc_device: cache file not writeable\n"); + err = -EINVAL; + goto err_close; + } + ns->pages_written = vmalloc(ns->geom.pgnum); + if (!ns->pages_written) { + NS_ERR("alloc_device: unable to allocate pages written array\n"); + err = -ENOMEM; + goto err_close; + } + ns->file_buf = kmalloc(ns->geom.pgszoob, GFP_KERNEL); + if (!ns->file_buf) { + NS_ERR("alloc_device: unable to allocate file buf\n"); + err = -ENOMEM; + goto err_free; + } + ns->cfile = cfile; + memset(ns->pages_written, 0, ns->geom.pgnum); + return 0; + } ns->pages = vmalloc(ns->geom.pgnum * sizeof(union ns_mem)); if (!ns->pages) { - NS_ERR("alloc_map: unable to allocate page array\n"); + NS_ERR("alloc_device: unable to allocate page array\n"); return -ENOMEM; } for (i = 0; i < ns->geom.pgnum; i++) { @@ -439,6 +486,12 @@ static int alloc_device(struct nandsim *ns) } return 0; + +err_free: + vfree(ns->pages_written); +err_close: + filp_close(cfile, NULL); + return err; } /* @@ -448,6 +501,13 @@ static void free_device(struct nandsim *ns) { int i; + if (ns->cfile) { + kfree(ns->file_buf); + vfree(ns->pages_written); + filp_close(ns->cfile, NULL); + return; + } + if (ns->pages) { for (i = 0; i < ns->geom.pgnum; i++) { if (ns->pages[i].byte) @@ -1211,6 +1271,97 @@ static int find_operation(struct nandsim *ns, uint32_t flag) return -1; } +static void put_pages(struct nandsim *ns) +{ + int i; + + for (i = 0; i < ns->held_cnt; i++) + page_cache_release(ns->held_pages[i]); +} + +/* Get page cache pages in advance to provide NOFS memory allocation */ +static int get_pages(struct nandsim *ns, struct file *file, size_t count, loff_t pos) +{ + pgoff_t index, start_index, end_index; + struct page *page; + struct address_space *mapping = file->f_mapping; + + start_index = pos >> PAGE_CACHE_SHIFT; + end_index = (pos + count - 1) >> PAGE_CACHE_SHIFT; + if (end_index - start_index + 1 > NS_MAX_HELD_PAGES) + return -EINVAL; + ns->held_cnt = 0; + for (index = start_index; index <= end_index; index++) { + page = find_get_page(mapping, index); + if (page == NULL) { + page = find_or_create_page(mapping, index, GFP_NOFS); + if (page == NULL) { + write_inode_now(mapping->host, 1); + page = find_or_create_page(mapping, index, GFP_NOFS); + } + if (page == NULL) { + put_pages(ns); + return -ENOMEM; + } + unlock_page(page); + } + ns->held_pages[ns->held_cnt++] = page; + } + return 0; +} + +static int set_memalloc(void) +{ + if (current->flags & PF_MEMALLOC) + return 0; + current->flags |= PF_MEMALLOC; + return 1; +} + +static void clear_memalloc(int memalloc) +{ + if (memalloc) + current->flags &= ~PF_MEMALLOC; +} + +static ssize_t read_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t *pos) +{ + mm_segment_t old_fs; + ssize_t tx; + int err, memalloc; + + err = get_pages(ns, file, count, *pos); + if (err) + return err; + old_fs = get_fs(); + set_fs(get_ds()); + memalloc = set_memalloc(); + tx = vfs_read(file, (char __user *)buf, count, pos); + clear_memalloc(memalloc); + set_fs(old_fs); + put_pages(ns); + return tx; +} + +static ssize_t write_file(struct nandsim *ns, struct file *file, void *buf, size_t count, loff_t *pos) +{ + mm_segment_t old_fs; + ssize_t tx; + int err, memalloc; + + err = get_pages(ns, file, count, *pos); + if (err) + return err; + old_fs = get_fs(); + set_fs(get_ds()); + memalloc = set_memalloc(); + tx = vfs_write(file, (char __user *)buf, count, pos); + clear_memalloc(memalloc); + set_fs(old_fs); + put_pages(ns); + return tx; +} + /* * Returns a pointer to the current page. */ @@ -1227,6 +1378,38 @@ static inline u_char *NS_PAGE_BYTE_OFF(struct nandsim *ns) return NS_GET_PAGE(ns)->byte + ns->regs.column + ns->regs.off; } +int do_read_error(struct nandsim *ns, int num) +{ + unsigned int page_no = ns->regs.row; + + if (read_error(page_no)) { + int i; + memset(ns->buf.byte, 0xFF, num); + for (i = 0; i < num; ++i) + ns->buf.byte[i] = random32(); + NS_WARN("simulating read error in page %u\n", page_no); + return 1; + } + return 0; +} + +void do_bit_flips(struct nandsim *ns, int num) +{ + if (bitflips && random32() < (1 << 22)) { + int flips = 1; + if (bitflips > 1) + flips = (random32() % (int) bitflips) + 1; + while (flips--) { + int pos = random32() % (num * 8); + ns->buf.byte[pos / 8] ^= (1 << (pos % 8)); + NS_WARN("read_page: flipping bit %d in page %d " + "reading from %d ecc: corrected=%u failed=%u\n", + pos, ns->regs.row, ns->regs.column + ns->regs.off, + nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed); + } + } +} + /* * Fill the NAND buffer with data read from the specified page. */ @@ -1234,36 +1417,40 @@ static void read_page(struct nandsim *ns, int num) { union ns_mem *mypage; + if (ns->cfile) { + if (!ns->pages_written[ns->regs.row]) { + NS_DBG("read_page: page %d not written\n", ns->regs.row); + memset(ns->buf.byte, 0xFF, num); + } else { + loff_t pos; + ssize_t tx; + + NS_DBG("read_page: page %d written, reading from %d\n", + ns->regs.row, ns->regs.column + ns->regs.off); + if (do_read_error(ns, num)) + return; + pos = (loff_t)ns->regs.row * ns->geom.pgszoob + ns->regs.column + ns->regs.off; + tx = read_file(ns, ns->cfile, ns->buf.byte, num, &pos); + if (tx != num) { + NS_ERR("read_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx); + return; + } + do_bit_flips(ns, num); + } + return; + } + mypage = NS_GET_PAGE(ns); if (mypage->byte == NULL) { NS_DBG("read_page: page %d not allocated\n", ns->regs.row); memset(ns->buf.byte, 0xFF, num); } else { - unsigned int page_no = ns->regs.row; NS_DBG("read_page: page %d allocated, reading from %d\n", ns->regs.row, ns->regs.column + ns->regs.off); - if (read_error(page_no)) { - int i; - memset(ns->buf.byte, 0xFF, num); - for (i = 0; i < num; ++i) - ns->buf.byte[i] = random32(); - NS_WARN("simulating read error in page %u\n", page_no); + if (do_read_error(ns, num)) return; - } memcpy(ns->buf.byte, NS_PAGE_BYTE_OFF(ns), num); - if (bitflips && random32() < (1 << 22)) { - int flips = 1; - if (bitflips > 1) - flips = (random32() % (int) bitflips) + 1; - while (flips--) { - int pos = random32() % (num * 8); - ns->buf.byte[pos / 8] ^= (1 << (pos % 8)); - NS_WARN("read_page: flipping bit %d in page %d " - "reading from %d ecc: corrected=%u failed=%u\n", - pos, ns->regs.row, ns->regs.column + ns->regs.off, - nsmtd->ecc_stats.corrected, nsmtd->ecc_stats.failed); - } - } + do_bit_flips(ns, num); } } @@ -1275,6 +1462,15 @@ static void erase_sector(struct nandsim *ns) union ns_mem *mypage; int i; + if (ns->cfile) { + for (i = 0; i < ns->geom.pgsec; i++) + if (ns->pages_written[ns->regs.row + i]) { + NS_DBG("erase_sector: freeing page %d\n", ns->regs.row + i); + ns->pages_written[ns->regs.row + i] = 0; + } + return; + } + mypage = NS_GET_PAGE(ns); for (i = 0; i < ns->geom.pgsec; i++) { if (mypage->byte != NULL) { @@ -1295,6 +1491,47 @@ static int prog_page(struct nandsim *ns, int num) union ns_mem *mypage; u_char *pg_off; + if (ns->cfile) { + loff_t off, pos; + ssize_t tx; + int all; + + NS_DBG("prog_page: writing page %d\n", ns->regs.row); + pg_off = ns->file_buf + ns->regs.column + ns->regs.off; + off = (loff_t)ns->regs.row * ns->geom.pgszoob + ns->regs.column + ns->regs.off; + if (!ns->pages_written[ns->regs.row]) { + all = 1; + memset(ns->file_buf, 0xff, ns->geom.pgszoob); + } else { + all = 0; + pos = off; + tx = read_file(ns, ns->cfile, pg_off, num, &pos); + if (tx != num) { + NS_ERR("prog_page: read error for page %d ret %ld\n", ns->regs.row, (long)tx); + return -1; + } + } + for (i = 0; i < num; i++) + pg_off[i] &= ns->buf.byte[i]; + if (all) { + pos = (loff_t)ns->regs.row * ns->geom.pgszoob; + tx = write_file(ns, ns->cfile, ns->file_buf, ns->geom.pgszoob, &pos); + if (tx != ns->geom.pgszoob) { + NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx); + return -1; + } + ns->pages_written[ns->regs.row] = 1; + } else { + pos = off; + tx = write_file(ns, ns->cfile, pg_off, num, &pos); + if (tx != num) { + NS_ERR("prog_page: write error for page %d ret %ld\n", ns->regs.row, (long)tx); + return -1; + } + } + return 0; + } + mypage = NS_GET_PAGE(ns); if (mypage->byte == NULL) { NS_DBG("prog_page: allocating page %d\n", ns->regs.row); |