diff options
Diffstat (limited to 'fs/squashfs/file.c')
-rw-r--r-- | fs/squashfs/file.c | 156 |
1 files changed, 147 insertions, 9 deletions
diff --git a/fs/squashfs/file.c b/fs/squashfs/file.c index 89d492916dea..8ba8c4c50770 100644 --- a/fs/squashfs/file.c +++ b/fs/squashfs/file.c @@ -39,6 +39,7 @@ #include "squashfs_fs_sb.h" #include "squashfs_fs_i.h" #include "squashfs.h" +#include "page_actor.h" /* * Locate cache slot in range [offset, index] for specified inode. If @@ -444,8 +445,9 @@ static int squashfs_readpage_sparse(struct page *page, int expected) return 0; } -static int squashfs_readpage(struct file *file, struct page *page) +static int squashfs_read_folio(struct file *file, struct folio *folio) { + struct page *page = &folio->page; struct inode *inode = page->mapping->host; struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info; int index = page->index >> (msblk->block_log - PAGE_SHIFT); @@ -453,7 +455,7 @@ static int squashfs_readpage(struct file *file, struct page *page) int expected = index == file_end ? (i_size_read(inode) & (msblk->block_size - 1)) : msblk->block_size; - int res; + int res = 0; void *pageaddr; TRACE("Entered squashfs_readpage, page index %lx, start block %llx\n", @@ -466,14 +468,15 @@ static int squashfs_readpage(struct file *file, struct page *page) if (index < file_end || squashfs_i(inode)->fragment_block == SQUASHFS_INVALID_BLK) { u64 block = 0; - int bsize = read_blocklist(inode, index, &block); - if (bsize < 0) + + res = read_blocklist(inode, index, &block); + if (res < 0) goto error_out; - if (bsize == 0) + if (res == 0) res = squashfs_readpage_sparse(page, expected); else - res = squashfs_readpage_block(page, block, bsize, expected); + res = squashfs_readpage_block(page, block, res, expected); } else res = squashfs_readpage_fragment(page, expected); @@ -487,14 +490,149 @@ out: memset(pageaddr, 0, PAGE_SIZE); kunmap_atomic(pageaddr); flush_dcache_page(page); - if (!PageError(page)) + if (res == 0) SetPageUptodate(page); unlock_page(page); - return 0; + return res; +} + +static int squashfs_readahead_fragment(struct page **page, + unsigned int pages, unsigned int expected) +{ + struct inode *inode = page[0]->mapping->host; + struct squashfs_cache_entry *buffer = squashfs_get_fragment(inode->i_sb, + squashfs_i(inode)->fragment_block, + squashfs_i(inode)->fragment_size); + struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info; + unsigned int n, mask = (1 << (msblk->block_log - PAGE_SHIFT)) - 1; + int error = buffer->error; + + if (error) + goto out; + + expected += squashfs_i(inode)->fragment_offset; + + for (n = 0; n < pages; n++) { + unsigned int base = (page[n]->index & mask) << PAGE_SHIFT; + unsigned int offset = base + squashfs_i(inode)->fragment_offset; + + if (expected > offset) { + unsigned int avail = min_t(unsigned int, expected - + offset, PAGE_SIZE); + + squashfs_fill_page(page[n], buffer, offset, avail); + } + + unlock_page(page[n]); + put_page(page[n]); + } + +out: + squashfs_cache_put(buffer); + return error; } +static void squashfs_readahead(struct readahead_control *ractl) +{ + struct inode *inode = ractl->mapping->host; + struct squashfs_sb_info *msblk = inode->i_sb->s_fs_info; + size_t mask = (1UL << msblk->block_log) - 1; + unsigned short shift = msblk->block_log - PAGE_SHIFT; + loff_t start = readahead_pos(ractl) & ~mask; + size_t len = readahead_length(ractl) + readahead_pos(ractl) - start; + struct squashfs_page_actor *actor; + unsigned int nr_pages = 0; + struct page **pages; + int i, file_end = i_size_read(inode) >> msblk->block_log; + unsigned int max_pages = 1UL << shift; + + readahead_expand(ractl, start, (len | mask) + 1); + + pages = kmalloc_array(max_pages, sizeof(void *), GFP_KERNEL); + if (!pages) + return; + + for (;;) { + pgoff_t index; + int res, bsize; + u64 block = 0; + unsigned int expected; + struct page *last_page; + + expected = start >> msblk->block_log == file_end ? + (i_size_read(inode) & (msblk->block_size - 1)) : + msblk->block_size; + + max_pages = (expected + PAGE_SIZE - 1) >> PAGE_SHIFT; + + nr_pages = __readahead_batch(ractl, pages, max_pages); + if (!nr_pages) + break; + + if (readahead_pos(ractl) >= i_size_read(inode)) + goto skip_pages; + + index = pages[0]->index >> shift; + + if ((pages[nr_pages - 1]->index >> shift) != index) + goto skip_pages; + + if (index == file_end && squashfs_i(inode)->fragment_block != + SQUASHFS_INVALID_BLK) { + res = squashfs_readahead_fragment(pages, nr_pages, + expected); + if (res) + goto skip_pages; + continue; + } + + bsize = read_blocklist(inode, index, &block); + if (bsize == 0) + goto skip_pages; + + actor = squashfs_page_actor_init_special(msblk, pages, nr_pages, + expected); + if (!actor) + goto skip_pages; + + res = squashfs_read_data(inode->i_sb, block, bsize, NULL, actor); + + last_page = squashfs_page_actor_free(actor); + + if (res == expected) { + int bytes; + + /* Last page (if present) may have trailing bytes not filled */ + bytes = res % PAGE_SIZE; + if (index == file_end && bytes && last_page) + memzero_page(last_page, bytes, + PAGE_SIZE - bytes); + + for (i = 0; i < nr_pages; i++) { + flush_dcache_page(pages[i]); + SetPageUptodate(pages[i]); + } + } + + for (i = 0; i < nr_pages; i++) { + unlock_page(pages[i]); + put_page(pages[i]); + } + } + + kfree(pages); + return; + +skip_pages: + for (i = 0; i < nr_pages; i++) { + unlock_page(pages[i]); + put_page(pages[i]); + } + kfree(pages); +} const struct address_space_operations squashfs_aops = { - .readpage = squashfs_readpage + .read_folio = squashfs_read_folio, + .readahead = squashfs_readahead }; |