11da177e4SLinus Torvalds /*
21da177e4SLinus Torvalds * JFFS2 -- Journalling Flash File System, Version 2.
31da177e4SLinus Torvalds *
4c00c310eSDavid Woodhouse * Copyright © 2001-2007 Red Hat, Inc.
56088c058SDavid Woodhouse * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
61da177e4SLinus Torvalds *
71da177e4SLinus Torvalds * Created by David Woodhouse <dwmw2@infradead.org>
81da177e4SLinus Torvalds *
91da177e4SLinus Torvalds * For licensing information, see the file 'LICENCE' in this directory.
101da177e4SLinus Torvalds *
111da177e4SLinus Torvalds */
121da177e4SLinus Torvalds
135a528957SJoe Perches #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
145a528957SJoe Perches
151da177e4SLinus Torvalds #include <linux/kernel.h>
161da177e4SLinus Torvalds #include <linux/fs.h>
171da177e4SLinus Torvalds #include <linux/time.h>
181da177e4SLinus Torvalds #include <linux/pagemap.h>
191da177e4SLinus Torvalds #include <linux/highmem.h>
201da177e4SLinus Torvalds #include <linux/crc32.h>
211da177e4SLinus Torvalds #include <linux/jffs2.h>
221da177e4SLinus Torvalds #include "nodelist.h"
231da177e4SLinus Torvalds
24205c109aSNick Piggin static int jffs2_write_end(struct file *filp, struct address_space *mapping,
25205c109aSNick Piggin loff_t pos, unsigned len, unsigned copied,
26205c109aSNick Piggin struct page *pg, void *fsdata);
27205c109aSNick Piggin static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
289d6b0cd7SMatthew Wilcox (Oracle) loff_t pos, unsigned len,
29205c109aSNick Piggin struct page **pagep, void **fsdata);
3075a47803SMatthew Wilcox (Oracle) static int jffs2_read_folio(struct file *filp, struct folio *folio);
311da177e4SLinus Torvalds
jffs2_fsync(struct file * filp,loff_t start,loff_t end,int datasync)3202c24a82SJosef Bacik int jffs2_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
331da177e4SLinus Torvalds {
347ea80859SChristoph Hellwig struct inode *inode = filp->f_mapping->host;
351da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
3602c24a82SJosef Bacik int ret;
371da177e4SLinus Torvalds
383b49c9a1SJeff Layton ret = file_write_and_wait_range(filp, start, end);
3902c24a82SJosef Bacik if (ret)
4002c24a82SJosef Bacik return ret;
4102c24a82SJosef Bacik
425955102cSAl Viro inode_lock(inode);
431da177e4SLinus Torvalds /* Trigger GC to flush any pending writes for this inode */
441da177e4SLinus Torvalds jffs2_flush_wbuf_gc(c, inode->i_ino);
455955102cSAl Viro inode_unlock(inode);
461da177e4SLinus Torvalds
471da177e4SLinus Torvalds return 0;
481da177e4SLinus Torvalds }
491da177e4SLinus Torvalds
504b6f5d20SArjan van de Ven const struct file_operations jffs2_file_operations =
511da177e4SLinus Torvalds {
521da177e4SLinus Torvalds .llseek = generic_file_llseek,
531da177e4SLinus Torvalds .open = generic_file_open,
54aad4f8bbSAl Viro .read_iter = generic_file_read_iter,
558174202bSAl Viro .write_iter = generic_file_write_iter,
560533400bSStoyan Gaydarov .unlocked_ioctl=jffs2_ioctl,
571da177e4SLinus Torvalds .mmap = generic_file_readonly_mmap,
581da177e4SLinus Torvalds .fsync = jffs2_fsync,
592cb1e089SDavid Howells .splice_read = filemap_splice_read,
6042984af0SJoel Stanley .splice_write = iter_file_splice_write,
611da177e4SLinus Torvalds };
621da177e4SLinus Torvalds
631da177e4SLinus Torvalds /* jffs2_file_inode_operations */
641da177e4SLinus Torvalds
6592e1d5beSArjan van de Ven const struct inode_operations jffs2_file_inode_operations =
661da177e4SLinus Torvalds {
67cac2f8b8SChristian Brauner .get_inode_acl = jffs2_get_acl,
68f2963d45SChristoph Hellwig .set_acl = jffs2_set_acl,
69aa98d7cfSKaiGai Kohei .setattr = jffs2_setattr,
70aa98d7cfSKaiGai Kohei .listxattr = jffs2_listxattr,
711da177e4SLinus Torvalds };
721da177e4SLinus Torvalds
73f5e54d6eSChristoph Hellwig const struct address_space_operations jffs2_file_address_operations =
741da177e4SLinus Torvalds {
7575a47803SMatthew Wilcox (Oracle) .read_folio = jffs2_read_folio,
76205c109aSNick Piggin .write_begin = jffs2_write_begin,
77205c109aSNick Piggin .write_end = jffs2_write_end,
781da177e4SLinus Torvalds };
791da177e4SLinus Torvalds
jffs2_do_readpage_nolock(struct inode * inode,struct page * pg)801da177e4SLinus Torvalds static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg)
811da177e4SLinus Torvalds {
821da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
831da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
841da177e4SLinus Torvalds unsigned char *pg_buf;
851da177e4SLinus Torvalds int ret;
861da177e4SLinus Torvalds
879c261b33SJoe Perches jffs2_dbg(2, "%s(): ino #%lu, page at offset 0x%lx\n",
8809cbfeafSKirill A. Shutemov __func__, inode->i_ino, pg->index << PAGE_SHIFT);
891da177e4SLinus Torvalds
90cd7619d6SMatt Mackall BUG_ON(!PageLocked(pg));
911da177e4SLinus Torvalds
921da177e4SLinus Torvalds pg_buf = kmap(pg);
931da177e4SLinus Torvalds /* FIXME: Can kmap fail? */
941da177e4SLinus Torvalds
9509cbfeafSKirill A. Shutemov ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_SHIFT,
9609cbfeafSKirill A. Shutemov PAGE_SIZE);
971da177e4SLinus Torvalds
981da177e4SLinus Torvalds if (ret) {
991da177e4SLinus Torvalds ClearPageUptodate(pg);
1001da177e4SLinus Torvalds SetPageError(pg);
1011da177e4SLinus Torvalds } else {
1021da177e4SLinus Torvalds SetPageUptodate(pg);
1031da177e4SLinus Torvalds ClearPageError(pg);
1041da177e4SLinus Torvalds }
1051da177e4SLinus Torvalds
1061da177e4SLinus Torvalds flush_dcache_page(pg);
1071da177e4SLinus Torvalds kunmap(pg);
1081da177e4SLinus Torvalds
1099c261b33SJoe Perches jffs2_dbg(2, "readpage finished\n");
11057ca7debSAnders Grafström return ret;
1111da177e4SLinus Torvalds }
1121da177e4SLinus Torvalds
__jffs2_read_folio(struct file * file,struct folio * folio)113e9b5b23eSMatthew Wilcox (Oracle) int __jffs2_read_folio(struct file *file, struct folio *folio)
1141da177e4SLinus Torvalds {
115e9b5b23eSMatthew Wilcox (Oracle) int ret = jffs2_do_readpage_nolock(folio->mapping->host, &folio->page);
116e9b5b23eSMatthew Wilcox (Oracle) folio_unlock(folio);
1171da177e4SLinus Torvalds return ret;
1181da177e4SLinus Torvalds }
1191da177e4SLinus Torvalds
jffs2_read_folio(struct file * file,struct folio * folio)12075a47803SMatthew Wilcox (Oracle) static int jffs2_read_folio(struct file *file, struct folio *folio)
1211da177e4SLinus Torvalds {
12275a47803SMatthew Wilcox (Oracle) struct jffs2_inode_info *f = JFFS2_INODE_INFO(folio->mapping->host);
1231da177e4SLinus Torvalds int ret;
1241da177e4SLinus Torvalds
125ced22070SDavid Woodhouse mutex_lock(&f->sem);
126e9b5b23eSMatthew Wilcox (Oracle) ret = __jffs2_read_folio(file, folio);
127ced22070SDavid Woodhouse mutex_unlock(&f->sem);
1281da177e4SLinus Torvalds return ret;
1291da177e4SLinus Torvalds }
1301da177e4SLinus Torvalds
jffs2_write_begin(struct file * filp,struct address_space * mapping,loff_t pos,unsigned len,struct page ** pagep,void ** fsdata)131205c109aSNick Piggin static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
1329d6b0cd7SMatthew Wilcox (Oracle) loff_t pos, unsigned len,
133205c109aSNick Piggin struct page **pagep, void **fsdata)
1341da177e4SLinus Torvalds {
135205c109aSNick Piggin struct page *pg;
136205c109aSNick Piggin struct inode *inode = mapping->host;
1371da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
138aa39cc67SKyeong Yoo struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
13909cbfeafSKirill A. Shutemov pgoff_t index = pos >> PAGE_SHIFT;
1401da177e4SLinus Torvalds int ret = 0;
1411da177e4SLinus Torvalds
1429c261b33SJoe Perches jffs2_dbg(1, "%s()\n", __func__);
1431da177e4SLinus Torvalds
14423892d38SYifei Liu if (pos > inode->i_size) {
14523892d38SYifei Liu /* Make new hole frag from old EOF to new position */
146157078f6SThomas Betker struct jffs2_raw_inode ri;
1471da177e4SLinus Torvalds struct jffs2_full_dnode *fn;
148157078f6SThomas Betker uint32_t alloc_len;
1491da177e4SLinus Torvalds
15023892d38SYifei Liu jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new position\n",
15123892d38SYifei Liu (unsigned int)inode->i_size, (uint32_t)pos);
1521da177e4SLinus Torvalds
153157078f6SThomas Betker ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
154157078f6SThomas Betker ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
155157078f6SThomas Betker if (ret)
156aa39cc67SKyeong Yoo goto out_err;
157157078f6SThomas Betker
158157078f6SThomas Betker mutex_lock(&f->sem);
1591da177e4SLinus Torvalds memset(&ri, 0, sizeof(ri));
1601da177e4SLinus Torvalds
1611da177e4SLinus Torvalds ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
1621da177e4SLinus Torvalds ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
1631da177e4SLinus Torvalds ri.totlen = cpu_to_je32(sizeof(ri));
1641da177e4SLinus Torvalds ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
1651da177e4SLinus Torvalds
1661da177e4SLinus Torvalds ri.ino = cpu_to_je32(f->inocache->ino);
1671da177e4SLinus Torvalds ri.version = cpu_to_je32(++f->highest_version);
1681da177e4SLinus Torvalds ri.mode = cpu_to_jemode(inode->i_mode);
1690cfe53d3SEric W. Biederman ri.uid = cpu_to_je16(i_uid_read(inode));
1700cfe53d3SEric W. Biederman ri.gid = cpu_to_je16(i_gid_read(inode));
17123892d38SYifei Liu ri.isize = cpu_to_je32((uint32_t)pos);
172c4592b9cSArnd Bergmann ri.atime = ri.ctime = ri.mtime = cpu_to_je32(JFFS2_NOW());
1731da177e4SLinus Torvalds ri.offset = cpu_to_je32(inode->i_size);
17423892d38SYifei Liu ri.dsize = cpu_to_je32((uint32_t)pos - inode->i_size);
1751da177e4SLinus Torvalds ri.csize = cpu_to_je32(0);
1761da177e4SLinus Torvalds ri.compr = JFFS2_COMPR_ZERO;
1771da177e4SLinus Torvalds ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
1781da177e4SLinus Torvalds ri.data_crc = cpu_to_je32(0);
1791da177e4SLinus Torvalds
1809fe4854cSDavid Woodhouse fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL);
1811da177e4SLinus Torvalds
1821da177e4SLinus Torvalds if (IS_ERR(fn)) {
1831da177e4SLinus Torvalds ret = PTR_ERR(fn);
1841da177e4SLinus Torvalds jffs2_complete_reservation(c);
185157078f6SThomas Betker mutex_unlock(&f->sem);
186aa39cc67SKyeong Yoo goto out_err;
1871da177e4SLinus Torvalds }
1881da177e4SLinus Torvalds ret = jffs2_add_full_dnode_to_inode(c, f, fn);
1891da177e4SLinus Torvalds if (f->metadata) {
1901da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, f->metadata->raw);
1911da177e4SLinus Torvalds jffs2_free_full_dnode(f->metadata);
1921da177e4SLinus Torvalds f->metadata = NULL;
1931da177e4SLinus Torvalds }
1941da177e4SLinus Torvalds if (ret) {
1959c261b33SJoe Perches jffs2_dbg(1, "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n",
1969c261b33SJoe Perches ret);
1971da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, fn->raw);
1981da177e4SLinus Torvalds jffs2_free_full_dnode(fn);
1991da177e4SLinus Torvalds jffs2_complete_reservation(c);
200157078f6SThomas Betker mutex_unlock(&f->sem);
201aa39cc67SKyeong Yoo goto out_err;
2021da177e4SLinus Torvalds }
2031da177e4SLinus Torvalds jffs2_complete_reservation(c);
20423892d38SYifei Liu inode->i_size = pos;
205157078f6SThomas Betker mutex_unlock(&f->sem);
2061da177e4SLinus Torvalds }
2071da177e4SLinus Torvalds
208205c109aSNick Piggin /*
209aa39cc67SKyeong Yoo * While getting a page and reading data in, lock c->alloc_sem until
210aa39cc67SKyeong Yoo * the page is Uptodate. Otherwise GC task may attempt to read the same
211aa39cc67SKyeong Yoo * page in read_cache_page(), which causes a deadlock.
212aa39cc67SKyeong Yoo */
213aa39cc67SKyeong Yoo mutex_lock(&c->alloc_sem);
214b7446e7cSMatthew Wilcox (Oracle) pg = grab_cache_page_write_begin(mapping, index);
215aa39cc67SKyeong Yoo if (!pg) {
216aa39cc67SKyeong Yoo ret = -ENOMEM;
217aa39cc67SKyeong Yoo goto release_sem;
218aa39cc67SKyeong Yoo }
219aa39cc67SKyeong Yoo *pagep = pg;
220aa39cc67SKyeong Yoo
221aa39cc67SKyeong Yoo /*
222205c109aSNick Piggin * Read in the page if it wasn't already present. Cannot optimize away
223205c109aSNick Piggin * the whole page write case until jffs2_write_end can handle the
224205c109aSNick Piggin * case of a short-copy.
225205c109aSNick Piggin */
226205c109aSNick Piggin if (!PageUptodate(pg)) {
227157078f6SThomas Betker mutex_lock(&f->sem);
2281da177e4SLinus Torvalds ret = jffs2_do_readpage_nolock(inode, pg);
229157078f6SThomas Betker mutex_unlock(&f->sem);
230aa39cc67SKyeong Yoo if (ret) {
231205c109aSNick Piggin unlock_page(pg);
23209cbfeafSKirill A. Shutemov put_page(pg);
233aa39cc67SKyeong Yoo goto release_sem;
234aa39cc67SKyeong Yoo }
235aa39cc67SKyeong Yoo }
236aa39cc67SKyeong Yoo jffs2_dbg(1, "end write_begin(). pg->flags %lx\n", pg->flags);
237aa39cc67SKyeong Yoo
238aa39cc67SKyeong Yoo release_sem:
239aa39cc67SKyeong Yoo mutex_unlock(&c->alloc_sem);
240aa39cc67SKyeong Yoo out_err:
2411da177e4SLinus Torvalds return ret;
2421da177e4SLinus Torvalds }
2431da177e4SLinus Torvalds
jffs2_write_end(struct file * filp,struct address_space * mapping,loff_t pos,unsigned len,unsigned copied,struct page * pg,void * fsdata)244205c109aSNick Piggin static int jffs2_write_end(struct file *filp, struct address_space *mapping,
245205c109aSNick Piggin loff_t pos, unsigned len, unsigned copied,
246205c109aSNick Piggin struct page *pg, void *fsdata)
2471da177e4SLinus Torvalds {
2481da177e4SLinus Torvalds /* Actually commit the write from the page cache page we're looking at.
2491da177e4SLinus Torvalds * For now, we write the full page out each time. It sucks, but it's simple
2501da177e4SLinus Torvalds */
251205c109aSNick Piggin struct inode *inode = mapping->host;
2521da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
2531da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
2541da177e4SLinus Torvalds struct jffs2_raw_inode *ri;
25509cbfeafSKirill A. Shutemov unsigned start = pos & (PAGE_SIZE - 1);
256205c109aSNick Piggin unsigned end = start + copied;
2571da177e4SLinus Torvalds unsigned aligned_start = start & ~3;
2581da177e4SLinus Torvalds int ret = 0;
2591da177e4SLinus Torvalds uint32_t writtenlen = 0;
2601da177e4SLinus Torvalds
2619c261b33SJoe Perches jffs2_dbg(1, "%s(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",
26209cbfeafSKirill A. Shutemov __func__, inode->i_ino, pg->index << PAGE_SHIFT,
2639c261b33SJoe Perches start, end, pg->flags);
2641da177e4SLinus Torvalds
2651da177e4SLinus Torvalds /* We need to avoid deadlock with page_cache_read() in
266205c109aSNick Piggin jffs2_garbage_collect_pass(). So the page must be
267205c109aSNick Piggin up to date to prevent page_cache_read() from trying
268205c109aSNick Piggin to re-lock it. */
269205c109aSNick Piggin BUG_ON(!PageUptodate(pg));
270205c109aSNick Piggin
27109cbfeafSKirill A. Shutemov if (end == PAGE_SIZE) {
272cf5eba53SDavid Woodhouse /* When writing out the end of a page, write out the
273cf5eba53SDavid Woodhouse _whole_ page. This helps to reduce the number of
274cf5eba53SDavid Woodhouse nodes in files which have many short writes, like
275cf5eba53SDavid Woodhouse syslog files. */
2762a754b51SNick Piggin aligned_start = 0;
277cf5eba53SDavid Woodhouse }
2781da177e4SLinus Torvalds
2791da177e4SLinus Torvalds ri = jffs2_alloc_raw_inode();
2801da177e4SLinus Torvalds
2811da177e4SLinus Torvalds if (!ri) {
2829c261b33SJoe Perches jffs2_dbg(1, "%s(): Allocation of raw inode failed\n",
2839c261b33SJoe Perches __func__);
284205c109aSNick Piggin unlock_page(pg);
28509cbfeafSKirill A. Shutemov put_page(pg);
2861da177e4SLinus Torvalds return -ENOMEM;
2871da177e4SLinus Torvalds }
2881da177e4SLinus Torvalds
2891da177e4SLinus Torvalds /* Set the fields that the generic jffs2_write_inode_range() code can't find */
2901da177e4SLinus Torvalds ri->ino = cpu_to_je32(inode->i_ino);
2911da177e4SLinus Torvalds ri->mode = cpu_to_jemode(inode->i_mode);
2920cfe53d3SEric W. Biederman ri->uid = cpu_to_je16(i_uid_read(inode));
2930cfe53d3SEric W. Biederman ri->gid = cpu_to_je16(i_gid_read(inode));
2941da177e4SLinus Torvalds ri->isize = cpu_to_je32((uint32_t)inode->i_size);
295c4592b9cSArnd Bergmann ri->atime = ri->ctime = ri->mtime = cpu_to_je32(JFFS2_NOW());
2961da177e4SLinus Torvalds
2971da177e4SLinus Torvalds /* In 2.4, it was already kmapped by generic_file_write(). Doesn't
2981da177e4SLinus Torvalds hurt to do it again. The alternative is ifdefs, which are ugly. */
2991da177e4SLinus Torvalds kmap(pg);
3001da177e4SLinus Torvalds
3011da177e4SLinus Torvalds ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,
30209cbfeafSKirill A. Shutemov (pg->index << PAGE_SHIFT) + aligned_start,
3031da177e4SLinus Torvalds end - aligned_start, &writtenlen);
3041da177e4SLinus Torvalds
3051da177e4SLinus Torvalds kunmap(pg);
3061da177e4SLinus Torvalds
3071da177e4SLinus Torvalds if (ret) {
3081da177e4SLinus Torvalds /* There was an error writing. */
3091da177e4SLinus Torvalds SetPageError(pg);
3101da177e4SLinus Torvalds }
3111da177e4SLinus Torvalds
3121da177e4SLinus Torvalds /* Adjust writtenlen for the padding we did, so we don't confuse our caller */
3132a754b51SNick Piggin writtenlen -= min(writtenlen, (start - aligned_start));
3141da177e4SLinus Torvalds
3151da177e4SLinus Torvalds if (writtenlen) {
3162a754b51SNick Piggin if (inode->i_size < pos + writtenlen) {
3172a754b51SNick Piggin inode->i_size = pos + writtenlen;
3181da177e4SLinus Torvalds inode->i_blocks = (inode->i_size + 511) >> 9;
3191da177e4SLinus Torvalds
320*d8b23c61SJeff Layton inode->i_mtime = inode_set_ctime_to_ts(inode,
321*d8b23c61SJeff Layton ITIME(je32_to_cpu(ri->ctime)));
3221da177e4SLinus Torvalds }
3231da177e4SLinus Torvalds }
3241da177e4SLinus Torvalds
3251da177e4SLinus Torvalds jffs2_free_raw_inode(ri);
3261da177e4SLinus Torvalds
3271da177e4SLinus Torvalds if (start+writtenlen < end) {
3281da177e4SLinus Torvalds /* generic_file_write has written more to the page cache than we've
3291da177e4SLinus Torvalds actually written to the medium. Mark the page !Uptodate so that
3301da177e4SLinus Torvalds it gets reread */
3319c261b33SJoe Perches jffs2_dbg(1, "%s(): Not all bytes written. Marking page !uptodate\n",
3329c261b33SJoe Perches __func__);
3331da177e4SLinus Torvalds SetPageError(pg);
3341da177e4SLinus Torvalds ClearPageUptodate(pg);
3351da177e4SLinus Torvalds }
3361da177e4SLinus Torvalds
3379c261b33SJoe Perches jffs2_dbg(1, "%s() returning %d\n",
3389c261b33SJoe Perches __func__, writtenlen > 0 ? writtenlen : ret);
339205c109aSNick Piggin unlock_page(pg);
34009cbfeafSKirill A. Shutemov put_page(pg);
341205c109aSNick Piggin return writtenlen > 0 ? writtenlen : ret;
3421da177e4SLinus Torvalds }
343