diff options
| -rw-r--r-- | fs/exofs/exofs.h | 6 | ||||
| -rw-r--r-- | fs/exofs/inode.c | 697 |
2 files changed, 703 insertions, 0 deletions
diff --git a/fs/exofs/exofs.h b/fs/exofs/exofs.h index 825454d76f6c..0276242326ab 100644 --- a/fs/exofs/exofs.h +++ b/fs/exofs/exofs.h @@ -130,6 +130,9 @@ static inline struct exofs_i_info *exofs_i(struct inode *inode) /* inode.c */ void exofs_truncate(struct inode *inode); int exofs_setattr(struct dentry *, struct iattr *); +int exofs_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata); /********************* * operation vectors * @@ -138,6 +141,9 @@ int exofs_setattr(struct dentry *, struct iattr *); extern const struct inode_operations exofs_file_inode_operations; extern const struct file_operations exofs_file_operations; +/* inode.c */ +extern const struct address_space_operations exofs_aops; + /* symlink.c */ extern const struct inode_operations exofs_symlink_inode_operations; extern const struct inode_operations exofs_fast_symlink_inode_operations; diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c index b0bda1e91225..a3691d8bfb98 100644 --- a/fs/exofs/inode.c +++ b/fs/exofs/inode.c @@ -35,6 +35,7 @@ #include <linux/writeback.h> #include <linux/buffer_head.h> +#include <scsi/scsi_device.h> #include "exofs.h" @@ -42,6 +43,702 @@ # define EXOFS_DEBUG_OBJ_ISIZE 1 #endif +struct page_collect { + struct exofs_sb_info *sbi; + struct request_queue *req_q; + struct inode *inode; + unsigned expected_pages; + + struct bio *bio; + unsigned nr_pages; + unsigned long length; + loff_t pg_first; /* keep 64bit also in 32-arches */ +}; + +static void _pcol_init(struct page_collect *pcol, unsigned expected_pages, + struct inode *inode) +{ + struct exofs_sb_info *sbi = inode->i_sb->s_fs_info; + struct request_queue *req_q = sbi->s_dev->scsi_device->request_queue; + + pcol->sbi = sbi; + pcol->req_q = req_q; + pcol->inode = inode; + pcol->expected_pages = expected_pages; + + pcol->bio = NULL; + pcol->nr_pages = 0; + pcol->length = 0; + pcol->pg_first = -1; + + EXOFS_DBGMSG("_pcol_init ino=0x%lx expected_pages=%u\n", inode->i_ino, + expected_pages); +} + +static void _pcol_reset(struct page_collect *pcol) +{ + pcol->expected_pages -= min(pcol->nr_pages, pcol->expected_pages); + + pcol->bio = NULL; + pcol->nr_pages = 0; + pcol->length = 0; + pcol->pg_first = -1; + EXOFS_DBGMSG("_pcol_reset ino=0x%lx expected_pages=%u\n", + pcol->inode->i_ino, pcol->expected_pages); + + /* this is probably the end of the loop but in writes + * it might not end here. don't be left with nothing + */ + if (!pcol->expected_pages) + pcol->expected_pages = 128; +} + +static int pcol_try_alloc(struct page_collect *pcol) +{ + int pages = min_t(unsigned, pcol->expected_pages, BIO_MAX_PAGES); + + for (; pages; pages >>= 1) { + pcol->bio = bio_alloc(GFP_KERNEL, pages); + if (likely(pcol->bio)) + return 0; + } + + EXOFS_ERR("Failed to kcalloc expected_pages=%u\n", + pcol->expected_pages); + return -ENOMEM; +} + +static void pcol_free(struct page_collect *pcol) +{ + bio_put(pcol->bio); + pcol->bio = NULL; +} + +static int pcol_add_page(struct page_collect *pcol, struct page *page, + unsigned len) +{ + int added_len = bio_add_pc_page(pcol->req_q, pcol->bio, page, len, 0); + if (unlikely(len != added_len)) + return -ENOMEM; + + ++pcol->nr_pages; + pcol->length += len; + return 0; +} + +static int update_read_page(struct page *page, int ret) +{ + if (ret == 0) { + /* Everything is OK */ + SetPageUptodate(page); + if (PageError(page)) + ClearPageError(page); + } else if (ret == -EFAULT) { + /* In this case we were trying to read something that wasn't on + * disk yet - return a page full of zeroes. This should be OK, + * because the object should be empty (if there was a write + * before this read, the read would be waiting with the page + * locked */ + clear_highpage(page); + + SetPageUptodate(page); + if (PageError(page)) + ClearPageError(page); + ret = 0; /* recovered error */ + EXOFS_DBGMSG("recovered read error\n"); + } else /* Error */ + SetPageError(page); + + return ret; +} + +static void update_write_page(struct page *page, int ret) +{ + if (ret) { + mapping_set_error(page->mapping, ret); + SetPageError(page); + } + end_page_writeback(page); +} + +/* Called at the end of reads, to optionally unlock pages and update their + * status. + */ +static int __readpages_done(struct osd_request *or, struct page_collect *pcol, + bool do_unlock) +{ + struct bio_vec *bvec; + int i; + u64 resid; + u64 good_bytes; + u64 length = 0; + int ret = exofs_check_ok_resid(or, &resid, NULL); + + osd_end_request(or); + + if (likely(!ret)) + good_bytes = pcol->length; + else if (!resid) + good_bytes = 0; + else + good_bytes = pcol->length - resid; + + EXOFS_DBGMSG("readpages_done(0x%lx) good_bytes=0x%llx" + " length=0x%lx nr_pages=%u\n", + pcol->inode->i_ino, _LLU(good_bytes), pcol->length, + pcol->nr_pages); + + __bio_for_each_segment(bvec, pcol->bio, i, 0) { + struct page *page = bvec->bv_page; + struct inode *inode = page->mapping->host; + int page_stat; + + if (inode != pcol->inode) + continue; /* osd might add more pages at end */ + + if (likely(length < good_bytes)) + page_stat = 0; + else + page_stat = ret; + + EXOFS_DBGMSG(" readpages_done(0x%lx, 0x%lx) %s\n", + inode->i_ino, page->index, + page_stat ? "bad_bytes" : "good_bytes"); + + ret = update_read_page(page, page_stat); + if (do_unlock) + unlock_page(page); + length += bvec->bv_len; + } + + pcol_free(pcol); + EXOFS_DBGMSG("readpages_done END\n"); + return ret; +} + +/* callback of async reads */ +static void readpages_done(struct osd_request *or, void *p) +{ + struct page_collect *pcol = p; + + __readpages_done(or, pcol, true); + atomic_dec(&pcol->sbi->s_curr_pending); + kfree(p); +} + +static void _unlock_pcol_pages(struct page_collect *pcol, int ret, int rw) +{ + struct bio_vec *bvec; + int i; + + __bio_for_each_segment(bvec, pcol->bio, i, 0) { + struct page *page = bvec->bv_page; + + if (rw == READ) + update_read_page(page, ret); + else + update_write_page(page, ret); + + unlock_page(page); + } + pcol_free(pcol); +} + +static int read_exec(struct page_collect *pcol, bool is_sync) +{ + struct exofs_i_info *oi = exofs_i(pcol->inode); + struct osd_obj_id obj = {pcol->sbi->s_pid, + pcol->inode->i_ino + EXOFS_OBJ_OFF}; + struct osd_request *or = NULL; + struct page_collect *pcol_copy = NULL; + loff_t i_start = pcol->pg_first << PAGE_CACHE_SHIFT; + int ret; + + if (!pcol->bio) + return 0; + + /* see comment in _readpage() about sync reads */ + WARN_ON(is_sync && (pcol->nr_pages != 1)); + + or = osd_start_request(pcol->sbi->s_dev, GFP_KERNEL); + if (unlikely(!or)) { + ret = -ENOMEM; + goto err; + } + + osd_req_read(or, &obj, pcol->bio, i_start); + + if (is_sync) { + exofs_sync_op(or, pcol->sbi->s_timeout, oi->i_cred); + return __readpages_done(or, pcol, false); + } + + pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL); + if (!pcol_copy) { + ret = -ENOMEM; + goto err; + } + + *pcol_copy = *pcol; + ret = exofs_async_op(or, readpages_done, pcol_copy, oi->i_cred); + if (unlikely(ret)) + goto err; + + atomic_inc(&pcol->sbi->s_curr_pending); + + EXOFS_DBGMSG("read_exec obj=0x%llx start=0x%llx length=0x%lx\n", + obj.id, _LLU(i_start), pcol->length); + + /* pages ownership was passed to pcol_copy */ + _pcol_reset(pcol); + return 0; + +err: + if (!is_sync) + _unlock_pcol_pages(pcol, ret, READ); + kfree(pcol_copy); + if (or) + osd_end_request(or); + return ret; +} + +/* readpage_strip is called either directly from readpage() or by the VFS from + * within read_cache_pages(), to add one more page to be read. It will try to + * collect as many contiguous pages as posible. If a discontinuity is + * encountered, or it runs out of resources, it will submit the previous segment + * and will start a new collection. Eventually caller must submit the last + * segment if present. + */ +static int readpage_strip(void *data, struct page *page) +{ + struct page_collect *pcol = data; + struct inode *inode = pcol->inode; + struct exofs_i_info *oi = exofs_i(inode); + loff_t i_size = i_size_read(inode); + pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT; + size_t len; + int ret; + + /* FIXME: Just for debugging, will be removed */ + if (PageUptodate(page)) + EXOFS_ERR("PageUptodate(0x%lx, 0x%lx)\n", pcol->inode->i_ino, + page->index); + + if (page->index < end_index) + len = PAGE_CACHE_SIZE; + else if (page->index == end_index) + len = i_size & ~PAGE_CACHE_MASK; + else + len = 0; + + if (!len || !obj_created(oi)) { + /* this will be out of bounds, or doesn't exist yet. + * Current page is cleared and the request is split + */ + clear_highpage(page); + + SetPageUptodate(page); + if (PageError(page)) + ClearPageError(page); + + unlock_page(page); + EXOFS_DBGMSG("readpage_strip(0x%lx, 0x%lx) empty page," + " splitting\n", inode->i_ino, page->index); + + return read_exec(pcol, false); + } + +try_again: + + if (unlikely(pcol->pg_first == -1)) { + pcol->pg_first = page->index; + } else if (unlikely((pcol->pg_first + pcol->nr_pages) != + page->index)) { + /* Discontinuity detected, split the request */ + ret = read_exec(pcol, false); + if (unlikely(ret)) + goto fail; + goto try_again; + } + + if (!pcol->bio) { + ret = pcol_try_alloc(pcol); + if (unlikely(ret)) + goto fail; + } + + if (len != PAGE_CACHE_SIZE) + zero_user(page, len, PAGE_CACHE_SIZE - len); + + EXOFS_DBGMSG(" readpage_strip(0x%lx, 0x%lx) len=0x%zx\n", + inode->i_ino, page->index, len); + + ret = pcol_add_page(pcol, page, len); + if (ret) { + EXOFS_DBGMSG("Failed pcol_add_page pages[i]=%p " + "this_len=0x%zx nr_pages=%u length=0x%lx\n", + page, len, pcol->nr_pages, pcol->length); + + /* split the request, and start again with current page */ + ret = read_exec(pcol, false); + if (unlikely(ret)) + goto fail; + + goto try_again; + } + + return 0; + +fail: + /* SetPageError(page); ??? */ + unlock_page(page); + return ret; +} + +static int exofs_readpages(struct file *file, struct address_space *mapping, + struct list_head *pages, unsigned nr_pages) +{ + struct page_collect pcol; + int ret; + + _pcol_init(&pcol, nr_pages, mapping->host); + + ret = read_cache_pages(mapping, pages, readpage_strip, &pcol); + if (ret) { + EXOFS_ERR("read_cache_pages => %d\n", ret); + return ret; + } + + return read_exec(&pcol, false); +} + +static int _readpage(struct page *page, bool is_sync) +{ + struct page_collect pcol; + int ret; + + _pcol_init(&pcol, 1, page->mapping->host); + + /* readpage_strip might call read_exec(,async) inside at several places + * but this is safe for is_async=0 since read_exec will not do anything + * when we have a single page. + */ + ret = readpage_strip(&pcol, page); + if (ret) { + EXOFS_ERR("_readpage => %d\n", ret); + return ret; + } + + return read_exec(&pcol, is_sync); +} + +/* + * We don't need the file + */ +static int exofs_readpage(struct file *file, struct page *page) +{ + return _readpage(page, false); +} + +/* Callback for osd_write. All writes are asynchronouse */ +static void writepages_done(struct osd_request *or, void *p) +{ + struct page_collect *pcol = p; + struct bio_vec *bvec; + int i; + u64 resid; + u64 good_bytes; + u64 length = 0; + + int ret = exofs_check_ok_resid(or, NULL, &resid); + + osd_end_request(or); + atomic_dec(&pcol->sbi->s_curr_pending); + + if (likely(!ret)) + good_bytes = pcol->length; + else if (!resid) + good_bytes = 0; + else + good_bytes = pcol->length - resid; + + EXOFS_DBGMSG("writepages_done(0x%lx) good_bytes=0x%llx" + " length=0x%lx nr_pages=%u\n", + pcol->inode->i_ino, _LLU(good_bytes), pcol->length, + pcol->nr_pages); + + __bio_for_each_segment(bvec, pcol->bio, i, 0) { + struct page *page = bvec->bv_page; + struct inode *inode = page->mapping->host; + int page_stat; + + if (inode != pcol->inode) + continue; /* osd might add more pages to a bio */ + + if (likely(length < good_bytes)) + page_stat = 0; + else + page_stat = ret; + + update_write_page(page, page_stat); + unlock_page(page); + EXOFS_DBGMSG(" writepages_done(0x%lx, 0x%lx) status=%d\n", + inode->i_ino, page->index, page_stat); + + length += bvec->bv_len; + } + + pcol_free(pcol); + kfree(pcol); + EXOFS_DBGMSG("writepages_done END\n"); +} + +static int write_exec(struct page_collect *pcol) +{ + struct exofs_i_info *oi = exofs_i(pcol->inode); + struct osd_obj_id obj = {pcol->sbi->s_pid, + pcol->inode->i_ino + EXOFS_OBJ_OFF}; + struct osd_request *or = NULL; + struct page_collect *pcol_copy = NULL; + loff_t i_start = pcol->pg_first << PAGE_CACHE_SHIFT; + int ret; + + if (!pcol->bio) + return 0; + + or = osd_start_request(pcol->sbi->s_dev, GFP_KERNEL); + if (unlikely(!or)) { + EXOFS_ERR("write_exec: Faild to osd_start_request()\n"); + ret = -ENOMEM; + goto err; + } + + pcol_copy = kmalloc(sizeof(*pcol_copy), GFP_KERNEL); + if (!pcol_copy) { + EXOFS_ERR("write_exec: Faild to kmalloc(pcol)\n"); + ret = -ENOMEM; + goto err; + } + + *pcol_copy = *pcol; + + osd_req_write(or, &obj, pcol_copy->bio, i_start); + ret = exofs_async_op(or, writepages_done, pcol_copy, oi->i_cred); + if (unlikely(ret)) { + EXOFS_ERR("write_exec: exofs_async_op() Faild\n"); + goto err; + } + + atomic_inc(&pcol->sbi->s_curr_pending); + EXOFS_DBGMSG("write_exec(0x%lx, 0x%llx) start=0x%llx length=0x%lx\n", + pcol->inode->i_ino, pcol->pg_first, _LLU(i_start), + pcol->length); + /* pages ownership was passed to pcol_copy */ + _pcol_reset(pcol); + return 0; + +err: + _unlock_pcol_pages(pcol, ret, WRITE); + kfree(pcol_copy); + if (or) + osd_end_request(or); + return ret; +} + +/* writepage_strip is called either directly from writepage() or by the VFS from + * within write_cache_pages(), to add one more page to be written to storage. + * It will try to collect as many contiguous pages as possible. If a + * discontinuity is encountered or it runs out of resources it will submit the + * previous segment and will start a new collection. + * Eventually caller must submit the last segment if present. + */ +static int writepage_strip(struct page *page, + struct writeback_control *wbc_unused, void *data) +{ + struct page_collect *pcol = data; + struct inode *inode = pcol->inode; + struct exofs_i_info *oi = exofs_i(inode); + loff_t i_size = i_size_read(inode); + pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT; + size_t len; + int ret; + + BUG_ON(!PageLocked(page)); + + ret = wait_obj_created(oi); + if (unlikely(ret)) + goto fail; + + if (page->index < end_index) + /* in this case, the page is within the limits of the file */ + len = PAGE_CACHE_SIZE; + else { + len = i_size & ~PAGE_CACHE_MASK; + + if (page->index > end_index || !len) { + /* in this case, the page is outside the limits + * (truncate in progress) + */ + ret = write_exec(pcol); + if (unlikely(ret)) + goto fail; + if (PageError(page)) + ClearPageError(page); + unlock_page(page); + return 0; + } + } + +try_again: + + if (unlikely(pcol->pg_first == -1)) { + pcol->pg_first = page->index; + } else if (unlikely((pcol->pg_first + pcol->nr_pages) != + page->index)) { + /* Discontinuity detected, split the request */ + ret = write_exec(pcol); + if (unlikely(ret)) + goto fail; + goto try_again; + } + + if (!pcol->bio) { + ret = pcol_try_alloc(pcol); + if (unlikely(ret)) + goto fail; + } + + EXOFS_DBGMSG(" writepage_strip(0x%lx, 0x%lx) len=0x%zx\n", + inode->i_ino, page->index, len); + + ret = pcol_add_page(pcol, page, len); + if (unlikely(ret)) { + EXOFS_DBGMSG("Failed pcol_add_page " + "nr_pages=%u total_length=0x%lx\n", + pcol->nr_pages, pcol->length); + + /* split the request, next loop will start again */ + ret = write_exec(pcol); + if (unlikely(ret)) { + EXOFS_DBGMSG("write_exec faild => %d", ret); + goto fail; + } + + goto try_again; + } + + BUG_ON(PageWriteback(page)); + set_page_writeback(page); + + return 0; + +fail: + set_bit(AS_EIO, &page->mapping->flags); + unlock_page(page); + return ret; +} + +static int exofs_writepages(struct address_space *mapping, + struct writeback_control *wbc) +{ + struct page_collect pcol; + long start, end, expected_pages; + int ret; + + start = wbc->range_start >> PAGE_CACHE_SHIFT; + end = (wbc->range_end == LLONG_MAX) ? + start + mapping->nrpages : + wbc->range_end >> PAGE_CACHE_SHIFT; + + if (start || end) + expected_pages = min(end - start + 1, 32L); + else + expected_pages = mapping->nrpages; + + EXOFS_DBGMSG("inode(0x%lx) wbc->start=0x%llx wbc->end=0x%llx" + " m->nrpages=%lu start=0x%lx end=0x%lx\n", + mapping->host->i_ino, wbc->range_start, wbc->range_end, + mapping->nrpages, start, end); + + _pcol_init(&pcol, expected_pages, mapping->host); + + ret = write_cache_pages(mapping, wbc, writepage_strip, &pcol); + if (ret) { + EXOFS_ERR("write_cache_pages => %d\n", ret); + return ret; + } + + return write_exec(&pcol); +} + +static int exofs_writepage(struct page *page, struct writeback_control *wbc) +{ + struct page_collect pcol; + int ret; + + _pcol_init(&pcol, 1, page->mapping->host); + + ret = writepage_strip(page, NULL, &pcol); + if (ret) { + EXOFS_ERR("exofs_writepage => %d\n", ret); + return ret; + } + + return write_exec(&pcol); +} + +int exofs_write_begin(struct file *file, struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata) +{ + int ret = 0; + struct page *page; + + page = *pagep; + if (page == NULL) { + ret = simple_write_begin(file, mapping, pos, len, flags, pagep, + fsdata); + if (ret) { + EXOFS_DBGMSG("simple_write_begin faild\n"); + return ret; + } + + page = *pagep; + } + + /* read modify write */ + if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) { + ret = _readpage(page, true); + if (ret) { + /*SetPageError was done by _readpage. Is it ok?*/ + unlock_page(page); + EXOFS_DBGMSG("__readpage_filler faild\n"); + } + } + + return ret; +} + +static int exofs_write_begin_export(struct file *file, + struct address_space *mapping, + loff_t pos, unsigned len, unsigned flags, + struct page **pagep, void **fsdata) +{ + *pagep = NULL; + + return exofs_write_begin(file, mapping, pos, len, flags, pagep, + fsdata); +} + +const struct address_space_operations exofs_aops = { + .readpage = exofs_readpage, + .readpages = exofs_readpages, + .writepage = exofs_writepage, + .writepages = exofs_writepages, + .write_begin = exofs_write_begin_export, + .write_end = simple_write_end, +}; + /****************************************************************************** * INODE OPERATIONS *****************************************************************************/ |