diff options
Diffstat (limited to 'fs/squashfs')
| -rw-r--r-- | fs/squashfs/Makefile | 4 | ||||
| -rw-r--r-- | fs/squashfs/file.c | 133 | ||||
| -rw-r--r-- | fs/squashfs/page_actor.h | 46 | ||||
| -rw-r--r-- | fs/squashfs/super.c | 33 |
4 files changed, 134 insertions, 82 deletions
diff --git a/fs/squashfs/Makefile b/fs/squashfs/Makefile index 7bd9b8b856d0..477c89a519ee 100644 --- a/fs/squashfs/Makefile +++ b/fs/squashfs/Makefile @@ -5,9 +5,9 @@ obj-$(CONFIG_SQUASHFS) += squashfs.o squashfs-y += block.o cache.o dir.o export.o file.o fragment.o id.o inode.o -squashfs-y += namei.o super.o symlink.o decompressor.o +squashfs-y += namei.o super.o symlink.o decompressor.o page_actor.o squashfs-$(CONFIG_SQUASHFS_FILE_CACHE) += file_cache.o -squashfs-$(CONFIG_SQUASHFS_FILE_DIRECT) += file_direct.o page_actor.o +squashfs-$(CONFIG_SQUASHFS_FILE_DIRECT) += file_direct.o squashfs-$(CONFIG_SQUASHFS_DECOMP_SINGLE) += decompressor_single.o squashfs-$(CONFIG_SQUASHFS_DECOMP_MULTI) += decompressor_multi.o squashfs-$(CONFIG_SQUASHFS_DECOMP_MULTI_PERCPU) += decompressor_multi_percpu.o diff --git a/fs/squashfs/file.c b/fs/squashfs/file.c index 7f0904b20329..98e64fec75b7 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 @@ -496,7 +497,137 @@ out: 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; + + if (buffer->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 buffer->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; + + 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; + + expected = index == file_end ? + (i_size_read(inode) & (msblk->block_size - 1)) : + msblk->block_size; + + 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); + + kfree(actor); + + if (res == expected) { + int bytes; + + /* Last page (if present) may have trailing bytes not filled */ + bytes = res % PAGE_SIZE; + if (pages[nr_pages - 1]->index == file_end && bytes) + memzero_page(pages[nr_pages - 1], 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 = { - .read_folio = squashfs_read_folio + .read_folio = squashfs_read_folio, + .readahead = squashfs_readahead }; diff --git a/fs/squashfs/page_actor.h b/fs/squashfs/page_actor.h index 37523c54256f..24841d28bc0f 100644 --- a/fs/squashfs/page_actor.h +++ b/fs/squashfs/page_actor.h @@ -6,51 +6,6 @@ * Phillip Lougher <phillip@squashfs.org.uk> */ -#ifndef CONFIG_SQUASHFS_FILE_DIRECT -struct squashfs_page_actor { - void **page; - int pages; - int length; - int next_page; -}; - -static inline struct squashfs_page_actor *squashfs_page_actor_init(void **page, - int pages, int length) -{ - struct squashfs_page_actor *actor = kmalloc(sizeof(*actor), GFP_KERNEL); - - if (actor == NULL) - return NULL; - - actor->length = length ? : pages * PAGE_SIZE; - actor->page = page; - actor->pages = pages; - actor->next_page = 0; - return actor; -} - -static inline void *squashfs_first_page(struct squashfs_page_actor *actor) -{ - actor->next_page = 1; - return actor->page[0]; -} - -static inline void *squashfs_next_page(struct squashfs_page_actor *actor) -{ - return actor->next_page == actor->pages ? NULL : - actor->page[actor->next_page++]; -} - -static inline void squashfs_finish_page(struct squashfs_page_actor *actor) -{ - /* empty */ -} - -static inline void squashfs_actor_nobuff(struct squashfs_page_actor *actor) -{ - /* empty */ -} -#else struct squashfs_page_actor { union { void **buffer; @@ -91,4 +46,3 @@ static inline void squashfs_actor_nobuff(struct squashfs_page_actor *actor) actor->alloc_buffer = 0; } #endif -#endif diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c index 6d594ba2ed28..32565dafa7f3 100644 --- a/fs/squashfs/super.c +++ b/fs/squashfs/super.c @@ -29,7 +29,6 @@ #include <linux/module.h> #include <linux/magic.h> #include <linux/xattr.h> -#include <linux/backing-dev.h> #include "squashfs_fs.h" #include "squashfs_fs_sb.h" @@ -113,24 +112,6 @@ static const struct squashfs_decompressor *supported_squashfs_filesystem( return decompressor; } -static int squashfs_bdi_init(struct super_block *sb) -{ - int err; - unsigned int major = MAJOR(sb->s_dev); - unsigned int minor = MINOR(sb->s_dev); - - bdi_put(sb->s_bdi); - sb->s_bdi = &noop_backing_dev_info; - - err = super_setup_bdi_name(sb, "squashfs_%u_%u", major, minor); - if (err) - return err; - - sb->s_bdi->ra_pages = 0; - sb->s_bdi->io_pages = 0; - - return 0; -} static int squashfs_fill_super(struct super_block *sb, struct fs_context *fc) { @@ -146,20 +127,6 @@ static int squashfs_fill_super(struct super_block *sb, struct fs_context *fc) TRACE("Entered squashfs_fill_superblock\n"); - /* - * squashfs provides 'backing_dev_info' in order to disable read-ahead. For - * squashfs, I/O is not deferred, it is done immediately in read_folio, - * which means the user would always have to wait their own I/O. So the effect - * of readahead is very weak for squashfs. squashfs_bdi_init will set - * sb->s_bdi->ra_pages and sb->s_bdi->io_pages to 0 and close readahead for - * squashfs. - */ - err = squashfs_bdi_init(sb); - if (err) { - errorf(fc, "squashfs init bdi failed"); - return err; - } - sb->s_fs_info = kzalloc(sizeof(*msblk), GFP_KERNEL); if (sb->s_fs_info == NULL) { ERROR("Failed to allocate squashfs_sb_info\n"); |