bcachefs: bch_folio can now handle multi-order folios

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/fs-io.c b/fs/bcachefs/fs-io.c
index eaee546c0fb96079a44667ada278a727312165e7..ad0b0c136e65de91cf36a529262387cab252bf58 100644 (file)
--- a/fs/bcachefs/fs-io.c
+++ b/fs/bcachefs/fs-io.c
@@ -381,7 +381,7 @@ struct bch_folio {
         * (Not the data itself)
         */
        bool                    uptodate;
-       struct bch_folio_sector s[PAGE_SECTORS];
+       struct bch_folio_sector s[];
 };
 
 static inline struct bch_folio *__bch2_folio(struct folio *folio)
@@ -415,7 +415,9 @@ static struct bch_folio *__bch2_folio_create(struct folio *folio, gfp_t gfp)
 {
        struct bch_folio *s;
 
-       s = kzalloc(sizeof(*s), GFP_NOFS|gfp);
+       s = kzalloc(sizeof(*s) +
+                   sizeof(struct bch_folio_sector) *
+                   folio_sectors(folio), GFP_NOFS|gfp);
        if (!s)
                return NULL;
 
@@ -1295,6 +1297,8 @@ int bch2_read_folio(struct file *file, struct folio *folio)
 struct bch_writepage_state {
        struct bch_writepage_io *io;
        struct bch_io_opts      opts;
+       struct bch_folio_sector *tmp;
+       unsigned                tmp_sectors;
 };
 
 static inline struct bch_writepage_state bch_writepage_state_init(struct bch_fs *c,
@@ -1422,7 +1426,7 @@ static int __bch2_writepage(struct folio *folio,
        struct bch_inode_info *inode = to_bch_ei(folio->mapping->host);
        struct bch_fs *c = inode->v.i_sb->s_fs_info;
        struct bch_writepage_state *w = data;
-       struct bch_folio *s, orig;
+       struct bch_folio *s;
        unsigned i, offset, f_sectors, nr_replicas_this_write = U32_MAX;
        loff_t i_size = i_size_read(&inode->v);
        int ret;
@@ -1453,6 +1457,13 @@ do_io:
        f_sectors = folio_sectors(folio);
        s = bch2_folio_create(folio, __GFP_NOFAIL);
 
+       if (f_sectors > w->tmp_sectors) {
+               kfree(w->tmp);
+               w->tmp = kzalloc(sizeof(struct bch_folio_sector) *
+                                f_sectors, __GFP_NOFAIL);
+               w->tmp_sectors = f_sectors;
+       }
+
        /*
         * Things get really hairy with errors during writeback:
         */
@@ -1461,7 +1472,7 @@ do_io:
 
        /* Before unlocking the page, get copy of reservations: */
        spin_lock(&s->lock);
-       orig = *s;
+       memcpy(w->tmp, s->s, sizeof(struct bch_folio_sector) * f_sectors);
        spin_unlock(&s->lock);
 
        for (i = 0; i < f_sectors; i++) {
@@ -1499,16 +1510,16 @@ do_io:
                u64 sector;
 
                while (offset < f_sectors &&
-                      orig.s[offset].state < SECTOR_DIRTY)
+                      w->tmp[offset].state < SECTOR_DIRTY)
                        offset++;
 
                if (offset == f_sectors)
                        break;
 
                while (offset + sectors < f_sectors &&
-                      orig.s[offset + sectors].state >= SECTOR_DIRTY) {
-                       reserved_sectors += orig.s[offset + sectors].replicas_reserved;
-                       dirty_sectors += orig.s[offset + sectors].state == SECTOR_DIRTY;
+                      w->tmp[offset + sectors].state >= SECTOR_DIRTY) {
+                       reserved_sectors += w->tmp[offset + sectors].replicas_reserved;
+                       dirty_sectors += w->tmp[offset + sectors].state == SECTOR_DIRTY;
                        sectors++;
                }
                BUG_ON(!sectors);
@@ -1568,6 +1579,7 @@ int bch2_writepages(struct address_space *mapping, struct writeback_control *wbc
        if (w.io)
                bch2_writepage_do_io(&w);
        blk_finish_plug(&plug);
+       kfree(w.tmp);
        return bch2_err_class(ret);
 }