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author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/jffs2/file.c | |
download | lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'fs/jffs2/file.c')
-rw-r--r-- | fs/jffs2/file.c | 290 |
1 files changed, 290 insertions, 0 deletions
diff --git a/fs/jffs2/file.c b/fs/jffs2/file.c new file mode 100644 index 000000000000..0c607c1388f4 --- /dev/null +++ b/fs/jffs2/file.c @@ -0,0 +1,290 @@ +/* + * JFFS2 -- Journalling Flash File System, Version 2. + * + * Copyright (C) 2001-2003 Red Hat, Inc. + * + * Created by David Woodhouse <dwmw2@infradead.org> + * + * For licensing information, see the file 'LICENCE' in this directory. + * + * $Id: file.c,v 1.99 2004/11/16 20:36:11 dwmw2 Exp $ + * + */ + +#include <linux/version.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/fs.h> +#include <linux/time.h> +#include <linux/pagemap.h> +#include <linux/highmem.h> +#include <linux/crc32.h> +#include <linux/jffs2.h> +#include "nodelist.h" + +extern int generic_file_open(struct inode *, struct file *) __attribute__((weak)); +extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) __attribute__((weak)); + +static int jffs2_commit_write (struct file *filp, struct page *pg, + unsigned start, unsigned end); +static int jffs2_prepare_write (struct file *filp, struct page *pg, + unsigned start, unsigned end); +static int jffs2_readpage (struct file *filp, struct page *pg); + +int jffs2_fsync(struct file *filp, struct dentry *dentry, int datasync) +{ + struct inode *inode = dentry->d_inode; + struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); + + /* Trigger GC to flush any pending writes for this inode */ + jffs2_flush_wbuf_gc(c, inode->i_ino); + + return 0; +} + +struct file_operations jffs2_file_operations = +{ + .llseek = generic_file_llseek, + .open = generic_file_open, + .read = generic_file_read, + .write = generic_file_write, + .ioctl = jffs2_ioctl, + .mmap = generic_file_readonly_mmap, + .fsync = jffs2_fsync, +#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,29) + .sendfile = generic_file_sendfile +#endif +}; + +/* jffs2_file_inode_operations */ + +struct inode_operations jffs2_file_inode_operations = +{ + .setattr = jffs2_setattr +}; + +struct address_space_operations jffs2_file_address_operations = +{ + .readpage = jffs2_readpage, + .prepare_write =jffs2_prepare_write, + .commit_write = jffs2_commit_write +}; + +static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg) +{ + struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); + struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); + unsigned char *pg_buf; + int ret; + + D2(printk(KERN_DEBUG "jffs2_do_readpage_nolock(): ino #%lu, page at offset 0x%lx\n", inode->i_ino, pg->index << PAGE_CACHE_SHIFT)); + + if (!PageLocked(pg)) + PAGE_BUG(pg); + + pg_buf = kmap(pg); + /* FIXME: Can kmap fail? */ + + ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE); + + if (ret) { + ClearPageUptodate(pg); + SetPageError(pg); + } else { + SetPageUptodate(pg); + ClearPageError(pg); + } + + flush_dcache_page(pg); + kunmap(pg); + + D2(printk(KERN_DEBUG "readpage finished\n")); + return 0; +} + +int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg) +{ + int ret = jffs2_do_readpage_nolock(inode, pg); + unlock_page(pg); + return ret; +} + + +static int jffs2_readpage (struct file *filp, struct page *pg) +{ + struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host); + int ret; + + down(&f->sem); + ret = jffs2_do_readpage_unlock(pg->mapping->host, pg); + up(&f->sem); + return ret; +} + +static int jffs2_prepare_write (struct file *filp, struct page *pg, + unsigned start, unsigned end) +{ + struct inode *inode = pg->mapping->host; + struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); + uint32_t pageofs = pg->index << PAGE_CACHE_SHIFT; + int ret = 0; + + D1(printk(KERN_DEBUG "jffs2_prepare_write()\n")); + + if (pageofs > inode->i_size) { + /* Make new hole frag from old EOF to new page */ + struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); + struct jffs2_raw_inode ri; + struct jffs2_full_dnode *fn; + uint32_t phys_ofs, alloc_len; + + D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n", + (unsigned int)inode->i_size, pageofs)); + + ret = jffs2_reserve_space(c, sizeof(ri), &phys_ofs, &alloc_len, ALLOC_NORMAL); + if (ret) + return ret; + + down(&f->sem); + memset(&ri, 0, sizeof(ri)); + + ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); + ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); + ri.totlen = cpu_to_je32(sizeof(ri)); + ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); + + ri.ino = cpu_to_je32(f->inocache->ino); + ri.version = cpu_to_je32(++f->highest_version); + ri.mode = cpu_to_jemode(inode->i_mode); + ri.uid = cpu_to_je16(inode->i_uid); + ri.gid = cpu_to_je16(inode->i_gid); + ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs)); + ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds()); + ri.offset = cpu_to_je32(inode->i_size); + ri.dsize = cpu_to_je32(pageofs - inode->i_size); + ri.csize = cpu_to_je32(0); + ri.compr = JFFS2_COMPR_ZERO; + ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); + ri.data_crc = cpu_to_je32(0); + + fn = jffs2_write_dnode(c, f, &ri, NULL, 0, phys_ofs, ALLOC_NORMAL); + + if (IS_ERR(fn)) { + ret = PTR_ERR(fn); + jffs2_complete_reservation(c); + up(&f->sem); + return ret; + } + ret = jffs2_add_full_dnode_to_inode(c, f, fn); + if (f->metadata) { + jffs2_mark_node_obsolete(c, f->metadata->raw); + jffs2_free_full_dnode(f->metadata); + f->metadata = NULL; + } + if (ret) { + D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in prepare_write, returned %d\n", ret)); + jffs2_mark_node_obsolete(c, fn->raw); + jffs2_free_full_dnode(fn); + jffs2_complete_reservation(c); + up(&f->sem); + return ret; + } + jffs2_complete_reservation(c); + inode->i_size = pageofs; + up(&f->sem); + } + + /* Read in the page if it wasn't already present, unless it's a whole page */ + if (!PageUptodate(pg) && (start || end < PAGE_CACHE_SIZE)) { + down(&f->sem); + ret = jffs2_do_readpage_nolock(inode, pg); + up(&f->sem); + } + D1(printk(KERN_DEBUG "end prepare_write(). pg->flags %lx\n", pg->flags)); + return ret; +} + +static int jffs2_commit_write (struct file *filp, struct page *pg, + unsigned start, unsigned end) +{ + /* Actually commit the write from the page cache page we're looking at. + * For now, we write the full page out each time. It sucks, but it's simple + */ + struct inode *inode = pg->mapping->host; + struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); + struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); + struct jffs2_raw_inode *ri; + unsigned aligned_start = start & ~3; + int ret = 0; + uint32_t writtenlen = 0; + + D1(printk(KERN_DEBUG "jffs2_commit_write(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n", + inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags)); + + if (!start && end == PAGE_CACHE_SIZE) { + /* We need to avoid deadlock with page_cache_read() in + jffs2_garbage_collect_pass(). So we have to mark the + page up to date, to prevent page_cache_read() from + trying to re-lock it. */ + SetPageUptodate(pg); + } + + ri = jffs2_alloc_raw_inode(); + + if (!ri) { + D1(printk(KERN_DEBUG "jffs2_commit_write(): Allocation of raw inode failed\n")); + return -ENOMEM; + } + + /* Set the fields that the generic jffs2_write_inode_range() code can't find */ + ri->ino = cpu_to_je32(inode->i_ino); + ri->mode = cpu_to_jemode(inode->i_mode); + ri->uid = cpu_to_je16(inode->i_uid); + ri->gid = cpu_to_je16(inode->i_gid); + ri->isize = cpu_to_je32((uint32_t)inode->i_size); + ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds()); + + /* In 2.4, it was already kmapped by generic_file_write(). Doesn't + hurt to do it again. The alternative is ifdefs, which are ugly. */ + kmap(pg); + + ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start, + (pg->index << PAGE_CACHE_SHIFT) + aligned_start, + end - aligned_start, &writtenlen); + + kunmap(pg); + + if (ret) { + /* There was an error writing. */ + SetPageError(pg); + } + + /* Adjust writtenlen for the padding we did, so we don't confuse our caller */ + if (writtenlen < (start&3)) + writtenlen = 0; + else + writtenlen -= (start&3); + + if (writtenlen) { + if (inode->i_size < (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen) { + inode->i_size = (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen; + inode->i_blocks = (inode->i_size + 511) >> 9; + + inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime)); + } + } + + jffs2_free_raw_inode(ri); + + if (start+writtenlen < end) { + /* generic_file_write has written more to the page cache than we've + actually written to the medium. Mark the page !Uptodate so that + it gets reread */ + D1(printk(KERN_DEBUG "jffs2_commit_write(): Not all bytes written. Marking page !uptodate\n")); + SetPageError(pg); + ClearPageUptodate(pg); + } + + D1(printk(KERN_DEBUG "jffs2_commit_write() returning %d\n",writtenlen?writtenlen:ret)); + return writtenlen?writtenlen:ret; +} |