xnu-3789.51.2.tar.gz

[apple/xnu.git] / bsd / vfs / vfs_bio.c

diff --git a/bsd/vfs/vfs_bio.c b/bsd/vfs/vfs_bio.c
index f54c98779039b84b26e3665fa6badbdff467c2f4..cdccdc82889c6e061f71774766b615291faa3027 100644 (file)
--- a/bsd/vfs/vfs_bio.c
+++ b/bsd/vfs/vfs_bio.c
@@ -171,9 +171,18 @@ static lck_attr_t  *buf_mtx_attr;
 static lck_grp_attr_t   *buf_mtx_grp_attr;
 static lck_mtx_t       *iobuffer_mtxp;
 static lck_mtx_t       *buf_mtxp;
+static lck_mtx_t       *buf_gc_callout;
 
 static int buf_busycount;
 
+#define FS_BUFFER_CACHE_GC_CALLOUTS_MAX_SIZE 16
+typedef struct {
+       void (* callout)(int, void *);
+       void *context;
+} fs_buffer_cache_gc_callout_t;
+
+fs_buffer_cache_gc_callout_t fs_callouts[FS_BUFFER_CACHE_GC_CALLOUTS_MAX_SIZE] = { {NULL, NULL} };
+
 static __inline__ int
 buf_timestamp(void)
 {
@@ -1329,7 +1338,8 @@ buf_strategy(vnode_t devvp, void *ap)
                        /* 
                         * Attach the file offset to this buffer.  The
                         * bufattr attributes will be passed down the stack
-                        * until they reach IOFlashStorage.  IOFlashStorage
+                        * until they reach the storage driver (whether 
+                        * IOFlashStorage, ASP, or IONVMe). The driver
                         * will retain the offset in a local variable when it
                         * issues its I/Os to the NAND controller.       
                         * 
@@ -1338,6 +1348,11 @@ buf_strategy(vnode_t devvp, void *ap)
                         * case, LwVM will update this field when it dispatches
                         * each I/O to IOFlashStorage.  But from our perspective
                         * we have only issued a single I/O.
+                        *
+                        * In the case of APFS we do not bounce through another 
+                        * intermediate layer (such as CoreStorage). APFS will
+                        * issue the I/Os directly to the block device / IOMedia
+                        * via buf_strategy on the specfs node.          
                         */
                        buf_setcpoff(bp, f_offset);
                        CP_DEBUG((CPDBG_OFFSET_IO | DBG_FUNC_NONE), (uint32_t) f_offset, (uint32_t) bp->b_lblkno, (uint32_t) bp->b_blkno, (uint32_t) bp->b_bcount, 0);
@@ -1991,6 +2006,7 @@ bufinit(void)
         */
        buf_mtxp        = lck_mtx_alloc_init(buf_mtx_grp, buf_mtx_attr);
        iobuffer_mtxp   = lck_mtx_alloc_init(buf_mtx_grp, buf_mtx_attr);
+       buf_gc_callout  = lck_mtx_alloc_init(buf_mtx_grp, buf_mtx_attr);
 
        if (iobuffer_mtxp == NULL)
                panic("couldn't create iobuffer mutex");
@@ -1998,6 +2014,9 @@ bufinit(void)
        if (buf_mtxp == NULL)
                panic("couldn't create buf mutex");
 
+       if (buf_gc_callout == NULL)
+               panic("couldn't create buf_gc_callout mutex");
+
        /*
         * allocate and initialize cluster specific global locks...
         */
@@ -2024,7 +2043,7 @@ bufinit(void)
  */
 
 #define MINMETA 512
-#define MAXMETA 8192
+#define MAXMETA 16384
 
 struct meta_zone_entry {
        zone_t mz_zone;
@@ -2039,6 +2058,7 @@ struct meta_zone_entry meta_zones[] = {
        {NULL, (MINMETA * 4),  16 * (MINMETA * 4), "buf.2048" },
        {NULL, (MINMETA * 8), 512 * (MINMETA * 8), "buf.4096" },
        {NULL, (MINMETA * 16), 512 * (MINMETA * 16), "buf.8192" },
+       {NULL, (MINMETA * 32), 512 * (MINMETA * 32), "buf.16384" },
        {NULL, 0, 0, "" } /* End */
 };
 
@@ -4496,6 +4516,50 @@ dump_buffer:
        return(0);
 }
 
+int
+fs_buffer_cache_gc_register(void (* callout)(int, void *), void *context)
+{
+       lck_mtx_lock(buf_gc_callout);
+       for (int i = 0; i < FS_BUFFER_CACHE_GC_CALLOUTS_MAX_SIZE; i++) {
+               if (fs_callouts[i].callout == NULL) {
+                       fs_callouts[i].callout = callout;
+                       fs_callouts[i].context = context;
+                       lck_mtx_unlock(buf_gc_callout);
+                       return 0;
+               }
+       }
+
+       lck_mtx_unlock(buf_gc_callout);
+       return ENOMEM;
+}
+
+int
+fs_buffer_cache_gc_unregister(void (* callout)(int, void *), void *context)
+{
+       lck_mtx_lock(buf_gc_callout);
+       for (int i = 0; i < FS_BUFFER_CACHE_GC_CALLOUTS_MAX_SIZE; i++) {
+               if (fs_callouts[i].callout == callout &&
+                   fs_callouts[i].context == context) {
+                       fs_callouts[i].callout = NULL;
+                       fs_callouts[i].context = NULL;
+               }
+       }
+       lck_mtx_unlock(buf_gc_callout);
+       return 0;
+}
+
+static void
+fs_buffer_cache_gc_dispatch_callouts(int all)
+{
+       lck_mtx_lock(buf_gc_callout);
+       for(int i = 0; i < FS_BUFFER_CACHE_GC_CALLOUTS_MAX_SIZE; i++) {
+               if (fs_callouts[i].callout != NULL) {
+                       fs_callouts[i].callout(all, fs_callouts[i].context);
+               }
+       }
+       lck_mtx_unlock(buf_gc_callout);
+}
+
 boolean_t 
 buffer_cache_gc(int all)
 {
@@ -4625,6 +4689,8 @@ buffer_cache_gc(int all)
 
        lck_mtx_unlock(buf_mtxp);
 
+       fs_buffer_cache_gc_dispatch_callouts(all);
+
        return did_large_zfree;
 }