diff options
Diffstat (limited to 'mm/shmem.c')
| -rw-r--r-- | mm/shmem.c | 66 |
1 files changed, 59 insertions, 7 deletions
diff --git a/mm/shmem.c b/mm/shmem.c index 935f3647bb..b66e99e2c7 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -254,7 +254,7 @@ static void shmem_inode_unacct_blocks(struct inode *inode, long pages) } static const struct super_operations shmem_ops; -const struct address_space_operations shmem_aops; +static const struct address_space_operations shmem_aops; static const struct file_operations shmem_file_operations; static const struct inode_operations shmem_inode_operations; static const struct inode_operations shmem_dir_inode_operations; @@ -263,6 +263,12 @@ static const struct vm_operations_struct shmem_vm_ops; static const struct vm_operations_struct shmem_anon_vm_ops; static struct file_system_type shmem_fs_type; +bool shmem_mapping(struct address_space *mapping) +{ + return mapping->a_ops == &shmem_aops; +} +EXPORT_SYMBOL_GPL(shmem_mapping); + bool vma_is_anon_shmem(struct vm_area_struct *vma) { return vma->vm_ops == &shmem_anon_vm_ops; @@ -1780,7 +1786,7 @@ static int shmem_replace_folio(struct folio **foliop, gfp_t gfp, xa_lock_irq(&swap_mapping->i_pages); error = shmem_replace_entry(swap_mapping, swap_index, old, new); if (!error) { - mem_cgroup_migrate(old, new); + mem_cgroup_replace_folio(old, new); __lruvec_stat_mod_folio(new, NR_FILE_PAGES, 1); __lruvec_stat_mod_folio(new, NR_SHMEM, 1); __lruvec_stat_mod_folio(old, NR_FILE_PAGES, -1); @@ -1960,6 +1966,9 @@ static int shmem_get_folio_gfp(struct inode *inode, pgoff_t index, int error; bool alloced; + if (WARN_ON_ONCE(!shmem_mapping(inode->i_mapping))) + return -EINVAL; + if (index > (MAX_LFS_FILESIZE >> PAGE_SHIFT)) return -EFBIG; repeat: @@ -2122,12 +2131,36 @@ unlock: return error; } +/** + * shmem_get_folio - find, and lock a shmem folio. + * @inode: inode to search + * @index: the page index. + * @foliop: pointer to the folio if found + * @sgp: SGP_* flags to control behavior + * + * Looks up the page cache entry at @inode & @index. If a folio is + * present, it is returned locked with an increased refcount. + * + * If the caller modifies data in the folio, it must call folio_mark_dirty() + * before unlocking the folio to ensure that the folio is not reclaimed. + * There is no need to reserve space before calling folio_mark_dirty(). + * + * When no folio is found, the behavior depends on @sgp: + * - for SGP_READ, *@foliop is %NULL and 0 is returned + * - for SGP_NOALLOC, *@foliop is %NULL and -ENOENT is returned + * - for all other flags a new folio is allocated, inserted into the + * page cache and returned locked in @foliop. + * + * Context: May sleep. + * Return: 0 if successful, else a negative error code. + */ int shmem_get_folio(struct inode *inode, pgoff_t index, struct folio **foliop, enum sgp_type sgp) { return shmem_get_folio_gfp(inode, index, foliop, sgp, mapping_gfp_mask(inode->i_mapping), NULL, NULL); } +EXPORT_SYMBOL_GPL(shmem_get_folio); /* * This is like autoremove_wake_function, but it removes the wait queue @@ -3493,10 +3526,10 @@ static int shmem_symlink(struct mnt_idmap *idmap, struct inode *dir, inode->i_op = &shmem_short_symlink_operations; } else { inode_nohighmem(inode); + inode->i_mapping->a_ops = &shmem_aops; error = shmem_get_folio(inode, 0, &folio, SGP_WRITE); if (error) goto out_remove_offset; - inode->i_mapping->a_ops = &shmem_aops; inode->i_op = &shmem_symlink_inode_operations; memcpy(folio_address(folio), symname, len); folio_mark_uptodate(folio); @@ -4258,6 +4291,24 @@ static int shmem_show_options(struct seq_file *seq, struct dentry *root) mpol_put(mpol); if (sbinfo->noswap) seq_printf(seq, ",noswap"); +#ifdef CONFIG_TMPFS_QUOTA + if (sb_has_quota_active(root->d_sb, USRQUOTA)) + seq_printf(seq, ",usrquota"); + if (sb_has_quota_active(root->d_sb, GRPQUOTA)) + seq_printf(seq, ",grpquota"); + if (sbinfo->qlimits.usrquota_bhardlimit) + seq_printf(seq, ",usrquota_block_hardlimit=%lld", + sbinfo->qlimits.usrquota_bhardlimit); + if (sbinfo->qlimits.grpquota_bhardlimit) + seq_printf(seq, ",grpquota_block_hardlimit=%lld", + sbinfo->qlimits.grpquota_bhardlimit); + if (sbinfo->qlimits.usrquota_ihardlimit) + seq_printf(seq, ",usrquota_inode_hardlimit=%lld", + sbinfo->qlimits.usrquota_ihardlimit); + if (sbinfo->qlimits.grpquota_ihardlimit) + seq_printf(seq, ",grpquota_inode_hardlimit=%lld", + sbinfo->qlimits.grpquota_ihardlimit); +#endif return 0; } @@ -4348,7 +4399,9 @@ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc) #ifdef CONFIG_TMPFS_POSIX_ACL sb->s_flags |= SB_POSIXACL; #endif - uuid_gen(&sb->s_uuid); + uuid_t uuid; + uuid_gen(&uuid); + super_set_uuid(sb, uuid.b, sizeof(uuid)); #ifdef CONFIG_TMPFS_QUOTA if (ctx->seen & SHMEM_SEEN_QUOTA) { @@ -4459,7 +4512,7 @@ static int shmem_error_remove_folio(struct address_space *mapping, return 0; } -const struct address_space_operations shmem_aops = { +static const struct address_space_operations shmem_aops = { .writepage = shmem_writepage, .dirty_folio = noop_dirty_folio, #ifdef CONFIG_TMPFS @@ -4471,7 +4524,6 @@ const struct address_space_operations shmem_aops = { #endif .error_remove_folio = shmem_error_remove_folio, }; -EXPORT_SYMBOL(shmem_aops); static const struct file_operations shmem_file_operations = { .mmap = shmem_mmap, @@ -4826,6 +4878,7 @@ struct file *shmem_kernel_file_setup(const char *name, loff_t size, unsigned lon { return __shmem_file_setup(shm_mnt, name, size, flags, S_PRIVATE); } +EXPORT_SYMBOL_GPL(shmem_kernel_file_setup); /** * shmem_file_setup - get an unlinked file living in tmpfs @@ -4903,7 +4956,6 @@ struct folio *shmem_read_folio_gfp(struct address_space *mapping, struct folio *folio; int error; - BUG_ON(!shmem_mapping(mapping)); error = shmem_get_folio_gfp(inode, index, &folio, SGP_CACHE, gfp, NULL, NULL); if (error) |