Btrfs (Linux): refactors Btrfs allocation to use profile string

Fixes #1941

Author: CarterLi

src/detection/btrfs/btrfs.h

@@ -8,8 +8,8 @@ typedef struct FFBtrfsDiskUsage
     uint64_t total;
     uint64_t used;
     const char* type;
-    bool dup;
-    uint8_t copies; // 1=single/raid0/raid5/raid6, 2=dup/raid1/raid10, 3=raid1c3, 4=raid1c4
+    const char* profile; // single / dup / raidx
+    uint8_t copies;
 } FFBtrfsDiskUsage;
 
 typedef struct FFBtrfsResult

src/detection/btrfs/btrfs_linux.c

@@ -73,35 +73,43 @@ static const char* detectAllocation(FFBtrfsResult* item, int dfd, FFstrbuf* buff
         item->globalReservationUsed = ffStrbufToUInt(buffer, 0);
     item->globalReservationUsed = item->globalReservationTotal - item->globalReservationUsed;
 
-    #define FF_BTRFS_DETECT_TYPE(index, _type) \
-    if (ffReadFileBufferRelative(subfd, #_type "/total_bytes", buffer)) \
-        item->allocation[index].total = ffStrbufToUInt(buffer, 0); \
-    \
-    if (ffReadFileBufferRelative(subfd, #_type "/bytes_used", buffer)) \
-        item->allocation[index].used = ffStrbufToUInt(buffer, 0); \
-    \
-    item->allocation[index].dup = faccessat(subfd, #_type "/dup/", F_OK, 0) == 0; \
+    #define FF_BTRFS_DETECT_PROFILE(_index, _type, _profile, _copies) \
+        else if (faccessat(subfd, _type "/" _profile "/", F_OK, 0) == 0) { \
+            item->allocation[_index].profile = _profile; \
+            item->allocation[_index].copies = _copies; \
+        }
+
+    #define FF_BTRFS_DETECT_TYPE(_index, _type) \
     do { \
-        uint8_t _copies = 1; \
-        if (faccessat(subfd, #_type "/raid1c4/", F_OK, 0) == 0) _copies = 4; \
-        else if (faccessat(subfd, #_type "/raid1c3/", F_OK, 0) == 0) _copies = 3; \
-        else if (faccessat(subfd, #_type "/raid1/",   F_OK, 0) == 0) _copies = 2; \
-        else if (faccessat(subfd, #_type "/raid10/",  F_OK, 0) == 0) _copies = 2; \
-        else if (item->allocation[index].dup) _copies = 2; /* DUP on single device */ \
-        item->allocation[index].copies = _copies; \
-    } while(0); \
-    \
-    item->allocation[index].type = #_type;
-
-    FF_BTRFS_DETECT_TYPE(0, data);
-    FF_BTRFS_DETECT_TYPE(1, metadata);
-    FF_BTRFS_DETECT_TYPE(2, system);
+        item->allocation[_index].type = _type; \
+        if (ffReadFileBufferRelative(subfd, _type "/total_bytes", buffer)) \
+            item->allocation[_index].total = ffStrbufToUInt(buffer, 0); \
+        \
+        if (ffReadFileBufferRelative(subfd, _type "/bytes_used", buffer)) \
+            item->allocation[_index].used = ffStrbufToUInt(buffer, 0); \
+        \
+        if (false) {} \
+        FF_BTRFS_DETECT_PROFILE(_index, _type, "single", 1) \
+        FF_BTRFS_DETECT_PROFILE(_index, _type, "dup", 2) \
+        FF_BTRFS_DETECT_PROFILE(_index, _type, "raid0", 1) \
+        FF_BTRFS_DETECT_PROFILE(_index, _type, "raid1", 2) \
+        FF_BTRFS_DETECT_PROFILE(_index, _type, "raid10", 2) \
+        FF_BTRFS_DETECT_PROFILE(_index, _type, "raid1c3", 3) \
+        FF_BTRFS_DETECT_PROFILE(_index, _type, "raid1c4", 4) \
+        FF_BTRFS_DETECT_PROFILE(_index, _type, "raid5", 1) /* (n-1)/n */ \
+        FF_BTRFS_DETECT_PROFILE(_index, _type, "raid6", 1) /* (n-2)/n */ \
+        else { \
+            item->allocation[_index].profile = "unknown"; \
+            item->allocation[_index].copies = 1; \
+        } \
+    } while (0)
+
+    FF_BTRFS_DETECT_TYPE(0, "data");
+    FF_BTRFS_DETECT_TYPE(1, "metadata");
+    FF_BTRFS_DETECT_TYPE(2, "system");
 
     #undef FF_BTRFS_DETECT_TYPE
 
-    if (item->allocation[0].copies > 1) // index 0 = data
-        item->totalSize /= item->allocation[0].copies;
-
     return NULL;
 }
 

src/modules/btrfs/btrfs.c

@@ -27,9 +27,9 @@ static void printBtrfs(FFBtrfsOptions* options, FFBtrfsResult* result, uint8_t i
     }
 
     uint64_t used = 0, allocated = 0, total = result->totalSize;
-    for (int i = 0; i < 3; ++i)
+    for (uint32_t i = 0; i < ARRAY_SIZE(result->allocation); ++i)
     {
-        uint64_t times = result->allocation[i].dup ? 2 : 1;
+        uint64_t times = result->allocation[i].copies;
         used += result->allocation[i].used * times;
         allocated += result->allocation[i].total * times;
     }
@@ -180,11 +180,11 @@ bool ffGenerateBtrfsJsonResult(FF_MAYBE_UNUSED FFBtrfsOptions* options, yyjson_m
         yyjson_mut_obj_add_uint(doc, obj, "sectorSize", btrfs->sectorSize);
         yyjson_mut_obj_add_uint(doc, obj, "totalSize", btrfs->totalSize);
         yyjson_mut_val* allocation = yyjson_mut_obj_add_arr(doc, obj, "allocation");
-        for (int i = 0; i < 3; ++i)
+        for (uint32_t i = 0; i < ARRAY_SIZE(btrfs->allocation); ++i)
         {
             yyjson_mut_val* item = yyjson_mut_arr_add_obj(doc, allocation);
             yyjson_mut_obj_add_str(doc, item, "type", btrfs->allocation[i].type);
-            yyjson_mut_obj_add_bool(doc, item, "dup", btrfs->allocation[i].dup);
+            yyjson_mut_obj_add_str(doc, item, "profile", btrfs->allocation[i].profile);
             yyjson_mut_obj_add_uint(doc, item, "copies", btrfs->allocation[i].copies);
             yyjson_mut_obj_add_uint(doc, item, "used", btrfs->allocation[i].used);
             yyjson_mut_obj_add_uint(doc, item, "total", btrfs->allocation[i].total);